High prevalence of pre-existing HBV polymerase mutations in pregnant women do not limit the telbivudine treatment efficacy

High prevalence of pre-existing HBV polymerase mutations in pregnant women do not limit the telbivudine treatment efficacy | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Help Center Sign In Submit a Preprint Cite Share Download PDF Research article High prevalence of pre-existing HBV polymerase mutations in pregnant women do not limit the telbivudine treatment efficacy Jing Wang, Jinfeng Liu, Qiang Yu, Li Jin, Naijuan Yao, Yuan Yang, and 6 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-44747/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: HBV resistant mutants in treatment-naïve patients may lead to antiviral treatment failure. It’s not clear if HBV resistant mutants present in the pregnant women before the antiviral treatment and the influence of the pre-existing resistant mutants on the short-term Telbivudine (TBV) therapy during the late pregnancy. Method: We enrolled 73 pregnant women with high HBV DNA load and TBV treatment during the pregnancy from 2012 to 2015 in this retrospective study. All subjects were followed at least 52 weeks postpartum. The UDPS was used to detect the HBV mutations before and after the TBV treatment. Results: Before TBV treatment, the complexity of HBV quasispecies of all subjects was 0.40± 0.09. At primary drug resistance mutation sites, 41.1% (30/73) and 53.4% (39/73) subjects had rtM204I/V and rtN236T/A detected, respectively; 9.6% (7/73) patients had more than 20% frequency mutation of rtM204I/V, which was also similar with high frequency of rtN236T/A mutation (41.1% vs. 53.4%, P = 0.136; frequencies > 20%: 9.6% vs. 5.5%, P = 0.347). After TBV treatment, 71.2% (52/73) subjects still had HBV DNA load ≥ 10 3 IU/mL at delivery. Among them, 75.0% patietns with rtM204I positive had HBV DNA load ≥ 10 3 IU/mL at delivery, which was comparable with the subjects without rtM204I (75.0% vs. 70.8%, P = 0.710). No changes were found in the frequencies and the complexity of HBV quasispecies of rtM204I mutation after the TVB treatment. Conclusion: The prevalence of pre-existing drug resistant mutations among the pregnant women was high using UPDS. However, the pre-existing HBV mutation had limited influence on the efficacy of short-term TBV treatment, and TBV treatment during late pregnancy seemed not to increase the risk of emerging HBV resistant mutants. Infectious Diseases HBV Ultra-deep pyrosequencing rtM204I/V telbivudine mutation. Figures Figure 1 Figure 2 Figure 3 Figure 4 1. Introduction Current guidelines recommend that pregnant women with high HBV DNA levels should accept antiviral prophylaxis in gestation [ 1 – 3 ]. It was recommended for pregnant women to decrease the HBV DNA load below a relative safe threshold for the prevention of HBV mother-to-infant transmission (MTIT) during the third trimester [ 4 ]. The nucleoside/nucleotide analogues (NAs) are able to suppress HBV replication by inhibiting the viral reverse transcriptase (RT), however, HBV RT has no proofreading activity, it increases the HBV mutations and promotes genetic diversity, which may cause drugs resistance [ 5 , 6 ]. Studies showed that some resistance mutations related to NAs therapy might already be present in treatment-naïve patients [ 7 – 9 ]. It is reported that YMDD mutations was present in a subgroup of NA-naïve patients with a frequency ranging from 3–27% [ 10 – 13 ]. HBV resistant mutants in treatment-naïve patients may lead to drug resistance and treatment failure [ 14 ]. It’s not clear if HBV resistant mutants present in the pregnant women before the antiviral treatment. Telbivudine (TBV) classified as category B is one of the NAs that recommended by the Asian-Pacific clinical practice guidelines and widely used to prevent MTIT. On the other hand, TBV and lamivudine (LAM) are considered with low genetic barrier to HBV resistance. LAM was observed drug-resistant viral variants among mothers with high HBV load received LAM treatment from 22 to 88 days during the pregnancy [ 15 ], while the study of TBV is still limited. Yingxia Liu et al. reported that one of 50 high HBV DNA loads subjects developed rtM204I drug-resistance mutation after receiving TBV treatment, but the time duration that the patient received TBV treatment in the study was not clear [ 16 ]. Another prospective study did not find the rtM204 mutations among the participants started TBV 600 mg/day at week 20 to week 32 of gestation and stopped TBV one month postpartum [ 17 ]. The clinical impact of short-duration TBV usage should be studied further in the high risk pregnant women. The objective of this study is to assess the prevalence of HBV pre-existing resistant mutants in pregnant women and explore the influence of the pre-existing resistant mutants on the efficacy of short-term TBV therapy during the pregnancy. We used ultra-deep pyrosequencing (UDPS) to sequence HBV and detect low level (< 1.0%) clinically relevant variants within complex viral populations. 2. Materials And Methods 2.1 Participants This is a retrospective study, all data were collected from another cohort study[ 18 ]. 73 chronic HBV infected pregnant women with high HBV DNA load undergoing routinely consultation from March 1st, 2012 to May 31st, 2015 were recruited from the First Affiliated Hospital of Xi’an Jiaotong University, Shaanxi, China. Inclusion criteria included pregnant women aged from 18 to 40 years, had serum HBsAg positive for more than 6 months and HBV DNA load greater than 10 6 IU/ml, started taking TBV (600 mg/day) from the 24th week of gestation and stopped TBV 12 weeks postpartum. Exclusion criteria were if patients were serologic HIV or hepatitis C or Hepatitis D virus positive, or if patients had anti-HBV treatment before the 24th week of gestation during the pregnancy, took the immunosuppressive agents during the pregnancy, and were diagnosed as any of the following diseases: gestational diabetes, arrhythmia, anemia or proteinuria. All patients were evaluated every 4 weeks from 24th week of gestation, at delivery, postpartum week (PPW) 4, 12, 24, and 52. The study was approved by the ethics committee of the First Affiliated Hospital of Xi’an Jiaotong University. Informed consent was obtained from each participant. All infants born to the chronic HBV infected mothers received combined immunoprophylaxis, 200 IU of hepatitis B immunoglobulin and 10 µg of recombinant HBV vaccine within 12 h postpartum, at 1 month, and at 6 months. 2.2 Ultra-deep pyrosequencing data To evaluate the risk of HBV drug resistance generated by the short duration of TBV in pregnancy, polymerase gene analysis was conducted by using UDPS prior to (at the 24th week of gestation) and after (at the last time point of follow-up) TBV treatment. The HBV RT was amplified (697 bp) with the primers Seq2 (5′-TTGGCCAAAATTCGCAGTC-3′) and OS2 (5′-TCTCTGACATACTTTCCAAT-3′) [ 15 ]. The PCR products were purified using an Omega gel extraction kit (Omega Bio-tek, USA) and quantified by a Nanodrop 1000 (Thermo Scientific, Wilmington, USA). UDPS was performed on the 454 Life Science platform (GS FLX platform, Roche). The sensitivity of UDPS on the 454 Life Science platform for detecting low-level viral variants at 0.1–1% has been confirmed by the use of standard cloning methods [ 19 – 21 ], the variants with prevalence larger than 1% were classified as high-confidence variants. The UDPS generated sequence reads were filtered using the following criteria: 1) mismatched base number of 5′ primers greater than 1; 2) no undetermined bases; 3) continuous same bases greater than 8; 4) 150 bases in length or less; 5) chimera sequence. The average number of reads generated for each sample was 9766 (range: 1913 to 21909). The filtered sequence reads were aligned to their respective consensus sequences, the Smith-Waterman algorithm and mutations in corresponding sites were used to calculate Sanger sequences. 2.3 HBV quasispecies complexity of AA The HBV quasispecies complexity of AA level was estimated for each site using Shannon entropy ( Sn ) [ 22 , 23 ], which can be calculated with the formula Sn = ๣∑ i ( p i Ln p i )/Ln N , where N is the total number of clones and p i is the frequency of each clone in the viral quasispecies population [ 24 ]. The mean viral complexity in each sample was calculated by the ratio of total amounts of the Sn at each position and the total length AA number. Mutations of rtL80, rtL82, rtV84, rtS85, rtI91, rtI169, rtV173, rtL180, rtA181, rtT184, rtA194, rtA200, rtS202, rtM204, rtV207, rtS213, rtV214, rtQ215, rtL217, rtE218, rtF221, rtL229, rtI233,rtN236, rtP237, rtN/H238, rtY245, rtM250 and rt S/C256 were analyzed in this study. 2.4 Other measurements Data of age, parity, antiviral treatment history before pregnancy, HBV family history, patients HBVDNA load, HBV serum markers titer including HBsAg and HBeAg, alanine transaminase (ALT) level and creatinine kinase (CK) at 24th, 28th, 32th, 36th week of gestation, delivery and postpartum week (PPW) 4, 12, 24, and 52, corresponding safety data of infants were collected from the medical records of the hospital. 2.5 Statistical Analysis Continuous variables were presented as means ± standard deviations and categorical variables were presented as counts (percentages). Paired t-tests were used to test the changes of the complex of HBV quasispecies before and after TBV treatment. The frequency of the mutations at rtM204 were compared using t-tests between patients with and without plasma HBV DNA < 10 3 IU/mL at delivery. All tests were two-side tests and p values < 0.05 were considered statistically significant. All analyses were performed with SPSS software 24.0 (SPSS Inc., Chicago, IL, USA). 3. Results 3.1 Baseline maternal characteristics Total 73 HBsAg (+) and HBV DNA load > 10 6 IU/mL pregnant women were enrolled in the current study. Subjects accepted TBV from 24th week of gestation to PPW 12, and then were followed up at least to PPW 52. The median follow-up time was 76 weeks (range: 52–152 weeks). The baseline demographics and clinical characteristics of the mothers were summarized in Table 1 . Six pregnant women (8.2%) accepted antiviral treatment before pregnancy, 3 had interferon treatment and 3 had LAM treatment. Table 1 Demographics and baseline characteristics Variable Value Age, years* 27.78 ± 3.89 Parity* 1.14 ± 0.35 Previous use of antiviral, number (%) 6 (8.22) HBV family history, number (%) 32 (43.84) ALT levels, U/L* 39.15 ± 43.97 ALT > 40 U/L, number (%) 22 (30.14) ALT > 80 U/L, number (%) 7 (9.59) ALT > 200 U/L, number (%) 1 (1.37) HBV DNA load, Log 10 IU/mL* 7.91 ± 0.70 HBsAg titer, Log 10 IU/mL* 4.38 ± 0.47 HBeAg titer, Log 10 s/co* 2.45 ± 1.26 HBeAg(+), number (%) 63 (86.30) *The values are expressed as means ± standard deviations for continuous variables and number of patients (percentages) for categorical variables. Abbreviations: ALT, alanine transaminase; HBeAg, hepatitis B e antigen; HBsAg, hepatitis B surface antigen; HBV, hepatitis B virus. 3.2 Dynamics of maternal HBV DNA load As showed in Fig. 1 , compared to baseline, TBV treatment declined HBV DNA level (4.36 ± 2.03, range 1.84 to 8.95 Log 10 IU/mL) in all mothers. There were 52 out of 73 (71.2%) women had serum HBV DNA load more than 10 3 IU/mL at delivery. Viral breakthrough was not observed during TBV treatment. After TBV withdrawal, HBV DNA levels rebounded in all mothers, and reached to a mean of 7.21 ± 1.34 Log 10 IU/mL after 3 months of the withdrawal (PPW 24). 3.3 Viral quasispecies complexity and NAs-resistant mutations before TBV treatment The complexity of viral quasispecies of the samples was calculated as described in Methods section. The complexity of quasispecies ( Sn ) before TBV treatment in all patients was 0.40 ± 0.09. The Sn value of treatment-naïve patients was 0.40 ± 0.10. The Sn value of the three patients who accepted LAM before pregnancy were 0.31, 0.36 and 0.36, respectively. The Sn value of the three patients who accepted interferon treatment before pregnancy were 0.45, 0.34 and 0.41, respectively (Fig. 2 ). The 29 known NAs-resistant mutations [ 25 , 26 ] were analyzed in the 73 pregnant women, At primary drug resistance mutation sites, rtM204I/V associated with resistance to LAM and TBV, also known as classical YMDD mutation, presented in 41.1% (30/73) patients before TBV treatment, 9.6% patients had mutation frequencies greater than 20%; RtA181T/V was in 5.5% (4/73) patients, which involves in the LAM, TBV and ADV shared resistance pathway; and rtN236T/A mutation, which was reported to decrease the sensitivity to TDF, presented in 53.4% (39/73) pregnant women, 5.5% patients had mutation frequencies greater than 20%. The proportions of patients with rtN236T/A mutation has no difference with those of patients with rtM204I/V mutation (41.1% vs. 53.4%, P = 0.136; frequencies greater than 20%: 9.6% vs. 5.5%, P = 0.347). At the compensatory mutation sites, 15.1% (11/73) participants had L80I/V mutation that is associated with resistance to LAM. In addition, the patients prior to TBV treatment also had other putative antiviral resistance mutations (Table 2 ). However, rtI169T, rtA194T, rtV173L, rtL180M, rtL82M, rtS85A, rtV207I, rtL217R and rtS/C256Gmutations were not present before TBV treatment. Two patients who accepted LAM before pregnancy had pre-existing rtM204I mutation. Table 2 Potential NAs mutation at 29 positions of HBV reverse transcriptase analyzed in the 73 pregnant women Mutations type Relationship with therapy The proportion of the patients with mutations, n (%) (n = 73) The frequency of the mutations* (%) Patients with mutations frequency > 20%, n (%) Primary resistance mutations rtI169T ETV 0 0 0 rtA181T/V LAM, TBV, ADV, TDF 4 (5.5) 0.023 ± 0.020 0 rtT184A/C/F/G/I/L/M/S ETV 52 (71.2) 0.13 ± 0.14 14 (19.2%) rtA194T ADV, TDF 0 0 0 rtS202C/G/I ETV 1 (1.4) 0.01 0 rtM204I/V LAM, ETV, TBV 30 (41.1) 0.13 ± 0.11 7 (9.6%) rtN236T/A ADV, TDF 39 (53.4) 0.10 ± 0.13 4 (5.5%) rtM250I/L/V 41 (56.2) 0.11 ± 0.08 5 (6.8%) Compensatory mutations rtL80I/V LAM 11 (15.1) 0.02 ± 0.01 rtV173L LAM 0 0 0 rtL180M LAM, ETV, TBV 0 0 0 Putative NAs mutations rtL82M LAM 0 0 0 rtV84M ADV 2 (2.7) 0.01 ± 0.001 0 rtS85A ADV 0 0 0 rtI91L LAM 40 (54.8) 0.82 ± 0.30 36 (49.3%) rtA200V LAM 1 (1.4) 0.02 0 rtV207I LAM 0 0 0 rtS213T ADV 3 (4.1) 0.11 ± 0.16 1 (1.4%) rtV214A ADV 3 (4.1) 0.01 ± 0.004 0 rtQ215P/S LAM, ADV 12 (16.4) 0.07 ± 0.08 2 (2.7) rtL217R ADV 0 0 0 rtE218D ADV 1 (1.4) 0.52 1 (1.4) rtF221Y ADV 30 (41.1) 0.29 ± 0.25 16 (21.9) rtL229G/V/W LAM 24 (32.9) 0.05 ± 0.06 1 (1.4) rtI233V ADV 30 (41.1) 0.12 ± 0.11 7 (9.6) rtP237H ADV 22 (30.1) 0.02 ± 0.02 0 rtN/H238D/S/T/A ADV 46 (63.0) 0.15 ± 0.12 7 (9.6) rtY245H ADV 1 (1.4) 0.13 0 rtS/C256G LAM, ETV 0 0 0 * The prevalence of mutations were expressed as number of patients (percentages) and the mutation frequencies were expressed as mean ± standard deviation. Abbreviations: ADV, adefovir dipivoxil; ETV, entecavir; HBV, hepatitis B virus; LAM, lamivudine; n, number; NA, nucleoside/nucleotide analogues; TBV, telbivudine; TDF, tenofovir disoproxil fumarate. As showed in Table 3 , 34.3% 25/73) patients had rtM204I mutation and 27.4% (20/73) had rtM204V mutation. Multi-base mutations combined with rtM204I/V was analyzed, rtM204I + rtN236T and rtM204V + rtN236T appeared to be the most common ones (16.4% and 17.8%, respectively). RtM204I/V + rtL80I/V and rtM204I + rtA181T/V may affect the sensitivity to LAM, TBV and ADV, they also presented but the proportions of the mutations were low (Table 3 ). Table 3 The multi-base mutations combined with rtM204I/V Types of mutation patterns The rate of the patients with mutations, n (%) (n = 73) rtM204I rtM204I alone 25 (34.3) rtM204I + rtL80I/V 5 (6.8) rtM204I + rtA181T/V 2 (2.7) rtM204I + rtL180M 0 rtM204I + rtN236T 12 (16.4) rtM204I + rtI233V 12 (16.4) rtM204I + rtA194T 0 rtM204V rtM204V alone 20 (27.4) rtM204V + rtL80I/V 5 (6.8) rtM204V + rtA181T/V 0 rtM204V + rtL180M 0 rtM204V + rtN236T 13 (17.8) rtM204V + rtI233V 9 (12.3) rtM204V + rtA194T 0 Abbreviations: n, number. 3.4 Pre-existing HBV mutations and the TBV treatment effect After receiving TBV treatment during the pregnancy, 71.2% (52/73) of patients still had HBV DNA load ≥ 10 3 IU/mL at delivery. The complex of HBV quasispecies of these patients were not found being significantly different from that of the patients with HBV DNA load less than 10 3 IU/mL at delivery (0.40 ± 0.09 vs. 0.40 ± 0.09, P = 0.353). The frequency of rtM204I was not significantly higher in patients with HBV DNA load ≥ 10 3 IU/mL than that of patients with HBV DNA < 10 3 IU/mL at delivery (0.13 ± 0.12 vs. 0.15 ± 0.11, P = 0.669), either. Among them, 75.0% patietns with rtM204I positive had HBV DNA load ≥ 10 3 IU/mL at delivery, which was comparable with the subjects without rtM204I (75.0% vs. 70.8%, P = 0.710). In addition, the patients were further divided into high mutation group (the frequency of rtM204I ≥ 20%, 10% and 5%) and low mutation group (the frequency < 20%, 10% and 5%) before the TBV treatment. As shown in Fig. 3 , the proportion of maternal HBV DNA load ≥ 10 3 IU/mL at delivery was 71.4% in the rtM204I ≥ 20% group, which was similar with that in the rtM204I < 20% group (71.4% vs. 72.3%, P = 0.961). Similar trend was observed in groups with 10% (72.7% vs. 72.1%, P = 0.968) and 5% frequency of rtM204I (62.5% vs. 75.0%, P = 0.325). 3.5 HBV mutations after the short-term TBV treatment The impact of TBV short-time treatment to HBV mutations was analyzed among the 73 pregnant women. No change was found in the frequencies of rtM204I mutation before and after (0.34 ± 0.23 vs. 0.32 ± 0.23, P = 0.681, Fig. 4 B) the TVB treatment. Compared with the HBV quasispecies complexity at baseline, there was no significant increase after the TBV treatment (0.40 ± 0.09 vs. 0.41 ± 0.12, P = 0.599, Fig. 4 A) as well. 3.6 Safety of TBV treatment TBV treatment was generally tolerated well by the mothers and their infants, there were no maternal severe adverse effects observed in this study. Mild creatinine kinase (CK) elevation (< 2 × ULN) was reported for 1 of 73 mothers (1.4%), and CK level normalized after telbivudine withdrawal (Table. S1). Among the 73 infants, there was no preterm, low birth weight, Apgar scores < 10 infant, and none of them had congenital deformities. No infant was found seropositive for HBsAg, HBeAg, and HBV DNA in the follow-up. 4. Discussion In our study, we found that the overall viral quasispecies complexity was 0.40 ± 0.09 and 30 of 73 patients (41.1%) had rtM204I/V positive, while 71.2% of pregnant women had serum HBV DNA load more than 10 3 IU/mL at delivery. It was reported that the pre-existing primary resistance mutations could reduce the susceptibility of anti-HBV monotherapy or even combined-therapy, such as rtM204I was refractory to LAM and TBV, the efficacy of the corresponding NAs could be affected[ 26 ]. We tested the association between the mutation frequency of rtM204I and the HBV DNA load decrease, no significant association was found in either high mutation frequency group or low mutation frequency group (Fig. 3 ), which indicated that the pre-existing primary resistance might have no influence on the short-term TBV treatment. Besides, rtN236T/A mutation that was related to decreasing sensitivity of tenofovir disoproxil fumarate (TDF) presented in 53.4% of the pregnant women, which had no difference with the proportion of the patients with rtM204I/V mutation. This indicated that TDF with high genetic barrier to HBV resistance might not be superior to TBV for the pregnant women to prevent MTIT from the view of pre-existing primary resistance mutations. We used UDPS to detect the drug resistance mutations, which is much more sensitive than the methods of many studies used before (5–20% variants detected in NAs-naïve patients)[ 10 – 12 ]. The UDPS can detect minor HBV variants and reveal the massive genetic heterogeneity by parallel amplification and detection of abundant small size sequences[ 27 ]; moreover, it can provide longer reads than other techniques and is suitable for viral resistance studies[ 28 ]. As far as we know, this is the first work to evaluate the pre-existing NA resistance mutations by UDPS in a moderate sample of pregnant women with chronic HBV infection. In the present study, 41.1% of patients were rtM204I/V positive, while only 9.6% (7/73) patients had rtM204I/V frequency 20% or more. In addition, the average frequency of the mutation was 0.13 ± 0.11, both of which were consistent with the previous study findings [ 10 – 12 ]. Two previous studies conducted rtM204I/V mutation testing with sensitive methods. Kirishima et al. reported 22.2% (4/18) NA-naïve patients had rtM204I/V mutation by peptide nucleic acid mediated polymerase chain reaction clamping which could detect mutation rate as low as 0.01 − 0.001% [ 13 ], and Ayres et al. detected 12.5% (3/24) pregnant women had the mutation by UDPS [ 15 ], which were lower than the rate in our study, the difference may be associated with the very limited sample sizes in the above two studies. Drug-resistant HBV variants were reported to emerge in the mothers accepted short-term LAM treatment during late pregnancy [ 15 ]. Han et al. reported rtM204 mutation arose in two mothers at 22 weeks and 71 weeks of TBV treatment, respectively [ 12 ]. In our study, approximately 7 months TBV treatment was administrated in the pregnant women. No increases of the viral quasispecies complexity and the frequency of rtM204I mutation were observed, which supplemented the safety of TBV treatment in late pregnancy. Furthermore, some pregnant women had multi-base mutations combined with rtM204I/V at baseline, including rtM204I + rtA181T/V, rtM204I/V + rtL80I/V, rtM204I/V + rtN236T, and rtM204I/V + rtI233V, which may affect their sensitivity to LAM, TBV, ADV and TDF. The complexity of viral quasispecies and the frequency of rtM204I mutation had no significant increase after TBV treatment in those pregnant women; however, caution has to be taken for them to choose NAs in subsequent long-term therapy due to the drug resistance mutations. In this study, the prevalence of HBV pre-existing resistant mutants in pregnant women, the influence of the efficacy of short-term TBV treatment and the drug-resistant mutations after TBV therapy were assessed retrospectively. Although the number of subjects was moderate, a prospective cohort study with larger sample size is necessary to evaluate the relationship between the HBV mutations and the antiviral treatment effect. In conclusion, the prevalence of pre-existing HBV mutation among the pregnant women was as high as 41.1%. However, the pre-existing HBV mutation had limited influence on the efficacy of short-term TBV treatment, and TBV treatment during late pregnancy seemed not to increase the risk of emerging HBV resistant mutants. Declarations Conflict of Interest Statements: All the authors declare that they have no competing interests, and all authors confirm its accuracy. Ethics approval: All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study protocol was approved by the ethics committee of the First Affiliated Hospital of Xi’an Jiaotong University 2010-Lunshenkezi-No. 13). Consent of publication: not applicable. Funding: The study was supported by the National Natural Science Foundation of China (No. 81702119, 81770594 and No. 81670537) and the Shaanxi Province Key Research and Development Foundation (2016SF-158 and 2017SF-043). Availability of data: The data in the current study are available from the corresponding author on reasonable request. Authors' contributions: TC, YH, YZ and JZ conceived of the presented idea. JW, JL, LJ, NY and QY acquired data in the study. YY, TY, CH and JW analyzed data. JW drafted the paper, and all authors discussed the results and contributed to the final manuscript. Acknowledgments: We thank all individuals who have participated in this study. We thank Prof. Gang Shi for their support and help to this study. References Terrault NA, Lok ASF, McMahon BJ, Chang KM, Hwang JP, Jonas MM, Brown RS, Jr., Bzowej NH, Wong JB: Update on Prevention, Diagnosis, and Treatment of Chronic Hepatitis B: AASLD 2018 Hepatitis B Guidance . 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Gastroenterology 2007, 132 (4):1574-1585. Ayres A, Yuen L, Jackson KM, Manoharan S, Glass A, Maley M, Yoo W, Hong SP, Kim SO, Luciani F et al : Short duration of lamivudine for the prevention of hepatitis B virus transmission in pregnancy: lack of potency and selection of resistance mutations . J Viral Hepat 2014, 21 (11):809-817. Liu Y, Wang M, Yao S, Yuan J, Lu J, Li H, Zeng W, Deng Y, Zou R, Li J et al : Efficacy and safety of telbivudine in different trimesters of pregnancy with high viremia for interrupting perinatal transmission of hepatitis B virus . Hepatol Res 2016, 46 (3):E181-188. Han GR, Cao MK, Zhao W, Jiang HX, Wang CM, Bai SF, Yue X, Wang GJ, Tang X, Fang ZX: A prospective and open-label study for the efficacy and safety of telbivudine in pregnancy for the prevention of perinatal transmission of hepatitis B virus infection . J Hepatol 2011, 55 (6):1215-1221. Liu J, Wang J, Jin D, Qi C, Yan T, Cao F, Jin L, Tian Z, Guo D, Yuan N et al : Hepatic flare after telbivudine withdrawal and efficacy of postpartum antiviral therapy for pregnancies with chronic hepatitis B virus . J Gastroenterol Hepatol 2017, 32 (1):177-183. Margulies M, Egholm M, Altman WE, Attiya S, Bader JS, Bemben LA, Berka J, Braverman MS, Chen YJ, Chen Z et al : Genome sequencing in microfabricated high-density picolitre reactors . Nature 2005, 437 (7057):376-380. Solmone M, Vincenti D, Prosperi MC, Bruselles A, Ippolito G, Capobianchi MR: Use of massively parallel ultradeep pyrosequencing to characterize the genetic diversity of hepatitis B virus in drug-resistant and drug-naive patients and to detect minor variants in reverse transcriptase and hepatitis B S antigen . J Virol 2009, 83 (4):1718-1726. Gong L, Han Y, Chen L, Liu F, Hao P, Sheng J, Li XH, Yu DM, Gong QM, Tian F et al : Comparison of next-generation sequencing and clone-based sequencing in analysis of hepatitis B virus reverse transcriptase quasispecies heterogeneity . J Clin Microbiol 2013, 51 (12):4087-4094. Nishijima N, Marusawa H, Ueda Y, Takahashi K, Nasu A, Osaki Y, Kou T, Yazumi S, Fujiwara T, Tsuchiya S et al : Dynamics of hepatitis B virus quasispecies in association with nucleos(t)ide analogue treatment determined by ultra-deep sequencing . PLoS One 2012, 7 (4):e35052. Yin F, Wu Z, Fang W, Wu C, Rayner S, Han M, Deng F, Du R, Liu J, Wang M et al : Resistant mutations and quasispecies complexity of hepatitis B virus during telbivudine treatment . J Gen Virol 2015, 96 (11):3302-3312. Domingo E, Martin V, Perales C, Grande-Perez A, Garcia-Arriaza J, Arias A: Viruses as quasispecies: biological implications . Curr Top Microbiol Immunol 2006, 299 :51-82. He X, Wang F, Huang B, Chen P, Zhong L: Detection and analysis of resistance mutations of hepatitis B virus . International journal of clinical and experimental medicine 2015, 8 (6):9630-9639. Liu BM, Li T, Xu J, Li XG, Dong JP, Yan P, Yang JX, Yan L, Gao ZY, Li WP et al : Characterization of potential antiviral resistance mutations in hepatitis B virus reverse transcriptase sequences in treatment-naive Chinese patients . Antiviral Res 2010, 85 (3):512-519. Sede M, Lopez-Ledesma M, Frider B, Pozzati M, Campos RH, Flichman D, Quarleri J: Hepatitis B virus depicts a high degree of conservation during the immune-tolerant phase in familiarly transmitted chronic hepatitis B infection: deep-sequencing and phylogenetic analysis . J Viral Hepat 2014, 21 (9):650-661. Rodriguez C, Chevaliez S, Bensadoun P, Pawlotsky JM: Characterization of the dynamics of hepatitis B virus resistance to adefovir by ultra-deep pyrosequencing . Hepatology 2013, 58 (3):890-901. Table S1 Table S1. Adverse events reported in current study* Adverse event Number (%) Gastrointestinal symptom 5 (6.85%) Nausea 1 (1.37) Emesis 1 (1.37) Diarrhea 1 (1.37) flatulence 1 (1.37) Dyspepsia 1 (1.37) Fatigue 2 (2.74) Dizziness 1 (1.37) Insomnia 2 (2.74) Myalgia 1 (1.37) CK elevation 1 (1.37) Cesarean delivery 35 (47.95) Threatened abortion 11 (15.07) Prolonged Labor 4 (6.25) *Number (percentages) of patients with adverse events were reported. Abbreviations: CK, creatinine kinase. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-44747","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research article","associatedPublications":[],"authors":[{"id":928302,"identity":"436fae8f-9773-4dfd-a93b-dcd437148206","order_by":0,"name":"Jing Wang","email":"","orcid":"https://orcid.org/0000-0001-6351-6758","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jing","middleName":"","lastName":"Wang","suffix":""},{"id":928303,"identity":"f79cf6dc-4420-4444-a3b0-64fb222412e6","order_by":1,"name":"Jinfeng Liu","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Jinfeng","middleName":"","lastName":"Liu","suffix":""},{"id":928304,"identity":"f97ce5c7-3ddd-4ff9-917d-5fb8bfbe2e2f","order_by":2,"name":"Qiang Yu","email":"","orcid":"","institution":"Second Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Qiang","middleName":"","lastName":"Yu","suffix":""},{"id":928305,"identity":"0a88a9d6-7943-4ac0-b185-d4dec380b6d0","order_by":3,"name":"Li Jin","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Li","middleName":"","lastName":"Jin","suffix":""},{"id":928306,"identity":"52630c53-ffd0-4858-a8fd-92f0c500ecf3","order_by":4,"name":"Naijuan Yao","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Naijuan","middleName":"","lastName":"Yao","suffix":""},{"id":928307,"identity":"adb336b1-2f5a-4ac6-9861-a493a9acdbb7","order_by":5,"name":"Yuan Yang","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yuan","middleName":"","lastName":"Yang","suffix":""},{"id":928308,"identity":"0eea6144-28a0-472e-9fba-98e5a63a8456","order_by":6,"name":"Taotao Yan","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Taotao","middleName":"","lastName":"Yan","suffix":""},{"id":928309,"identity":"6ab2ab47-5cee-4121-93bf-22aa8b3c2c75","order_by":7,"name":"Chunhua Hu","email":"","orcid":"","institution":"Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Chunhua","middleName":"","lastName":"Hu","suffix":""},{"id":928310,"identity":"24d28c10-88c8-4e4b-8253-156df45b1433","order_by":8,"name":"Yingli He","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yingli","middleName":"","lastName":"He","suffix":""},{"id":928311,"identity":"f844c78c-8745-4cd1-be60-d6b465741ae6","order_by":9,"name":"Yingren Zhao","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yingren","middleName":"","lastName":"Zhao","suffix":""},{"id":928312,"identity":"dfe52936-14a4-49f2-b067-0885b033cd11","order_by":10,"name":"Tianyan Chen","email":"","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Tianyan","middleName":"","lastName":"Chen","suffix":""},{"id":928313,"identity":"ca3e5b3b-fcc9-406a-aa33-a60aaf52c87b","order_by":11,"name":"Jie Zheng","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6ElEQVRIie2RsQrCMBCGTwJxSemqg/gKkYAuUl8lJeDk4OjgEAjopquCD1EQnAMHuvgADg6CUBcHwV1tq3PsKJhvuSPcx134ATyeH6RiAEjehACyeNCllbqGWJdScgqF2/f0d4VMCd6Ho2O0PsjLmUG3kViSntyHUSkW+1Rt9jY2DPoisbTD3QrjKpigau90rmCcWEZrbiW8YfBAJQzkyrOMwiom0BjxarHFllGoIGyLspb9ZbniSiyRtp1Ka47nOxtjL1wM5O06ihqznUndin7XLEYms3TgE5OD5qf2AKr2y6zH4/H8Ky8FK0qx7rDDDQAAAABJRU5ErkJggg==","orcid":"","institution":"First Affiliated Hospital, School of Medicine, Xi'an Jiaotong University","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Jie","middleName":"","lastName":"Zheng","suffix":""}],"badges":[],"createdAt":"2020-07-17 10:33:10","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-44747/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-44747/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":1677135,"identity":"7a960ee4-7f71-4e1c-ab37-0f0d093bd5c7","added_by":"auto","created_at":"2020-07-24 19:06:55","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":95418,"visible":true,"origin":"","legend":"HBV DNA load kinetics in pregnancy and postpartum. Abbreviations: HBV, hepatitis B virus; W, week; PPW, postpartum week.","description":"","filename":"Onlinefig1.Png","url":"https://assets-eu.researchsquare.com/files/rs-44747/v1/Onlinefig1.Png"},{"id":1677136,"identity":"d8e9c05a-2f8a-4b28-8b52-9045e84021c7","added_by":"auto","created_at":"2020-07-24 19:06:56","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":193156,"visible":true,"origin":"","legend":"Scatter diagram of HBV quasispecies complexity. Abbreviations: IFN, interferon; LAM, lamivudine.","description":"","filename":"Onlinefig2.Png","url":"https://assets-eu.researchsquare.com/files/rs-44747/v1/Onlinefig2.Png"},{"id":1677137,"identity":"fa9c0b37-7a2a-4dfe-80f6-f81ca454cebf","added_by":"auto","created_at":"2020-07-24 19:06:56","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":163321,"visible":true,"origin":"","legend":"The relation between the frequency of rtM204I and maternal HBV DNA load at delivery. Abbreviations: HBV, hepatitis B virus.","description":"","filename":"Onlinefig3.Png","url":"https://assets-eu.researchsquare.com/files/rs-44747/v1/Onlinefig3.Png"},{"id":1677138,"identity":"fdec2c43-b67f-4249-8157-26d7bd0acada","added_by":"auto","created_at":"2020-07-24 19:06:56","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":176935,"visible":true,"origin":"","legend":"The impact of telbivudine short-time treatment to HBV mutations: (A) The change of HBV quasispecies complexity before and after telbivudine treatment; (B) The change of rtM204I mutation frequency before and after telbivudine treatment.","description":"","filename":"Onlinefig4.Png","url":"https://assets-eu.researchsquare.com/files/rs-44747/v1/Onlinefig4.Png"},{"id":13559943,"identity":"8cc4876d-cb7e-4a88-82e8-9755b8f08184","added_by":"auto","created_at":"2021-09-17 03:02:46","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1728525,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-44747/v1/eae3ab98-c9b4-47fb-a6ea-a91fd152e3ec.pdf"}],"financialInterests":"","formattedTitle":"High prevalence of pre-existing HBV polymerase mutations in pregnant women do not limit the telbivudine treatment efficacy","fulltext":[{"header":"1. Introduction","content":" \u003cp\u003eCurrent guidelines recommend that pregnant women with high HBV DNA levels should accept antiviral prophylaxis in gestation [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. It was recommended for pregnant women to decrease the HBV DNA load below a relative safe threshold for the prevention of HBV mother-to-infant transmission (MTIT) during the third trimester [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe nucleoside/nucleotide analogues (NAs) are able to suppress HBV replication by inhibiting the viral reverse transcriptase (RT), however, HBV RT has no proofreading activity, it increases the HBV mutations and promotes genetic diversity, which may cause drugs resistance [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Studies showed that some resistance mutations related to NAs therapy might already be present in treatment-na\u0026iuml;ve patients [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. It is reported that YMDD mutations was present in a subgroup of NA-na\u0026iuml;ve patients with a frequency ranging from 3\u0026ndash;27% [\u003cspan additionalcitationids=\"CR11 CR12\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]. HBV resistant mutants in treatment-na\u0026iuml;ve patients may lead to drug resistance and treatment failure [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. It\u0026rsquo;s not clear if HBV resistant mutants present in the pregnant women before the antiviral treatment.\u003c/p\u003e \u003cp\u003eTelbivudine (TBV) classified as category B is one of the NAs that recommended by the Asian-Pacific clinical practice guidelines and widely used to prevent MTIT. On the other hand, TBV and lamivudine (LAM) are considered with low genetic barrier to HBV resistance. LAM was observed drug-resistant viral variants among mothers with high HBV load received LAM treatment from 22 to 88 days during the pregnancy [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], while the study of TBV is still limited. Yingxia Liu \u003cem\u003eet al.\u003c/em\u003e reported that one of 50 high HBV DNA loads subjects developed rtM204I drug-resistance mutation after receiving TBV treatment, but the time duration that the patient received TBV treatment in the study was not clear [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e]. Another prospective study did not find the rtM204 mutations among the participants started TBV 600\u0026nbsp;mg/day at week 20 to week 32 of gestation and stopped TBV one month postpartum [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. The clinical impact of short-duration TBV usage should be studied further in the high risk pregnant women.\u003c/p\u003e \u003cp\u003eThe objective of this study is to assess the prevalence of HBV pre-existing resistant mutants in pregnant women and explore the influence of the pre-existing resistant mutants on the efficacy of short-term TBV therapy during the pregnancy. We used ultra-deep pyrosequencing (UDPS) to sequence HBV and detect low level (\u0026lt;\u0026thinsp;1.0%) clinically relevant variants within complex viral populations.\u003c/p\u003e "},{"header":"2. Materials And Methods","content":" \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Participants\u003c/h2\u003e \u003cp\u003eThis is a retrospective study, all data were collected from another cohort study[\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e]. 73 chronic HBV infected pregnant women with high HBV DNA load undergoing routinely consultation from March 1st, 2012 to May 31st, 2015 were recruited from the First Affiliated Hospital of Xi\u0026rsquo;an Jiaotong University, Shaanxi, China. Inclusion criteria included pregnant women aged from 18 to 40 years, had serum HBsAg positive for more than 6\u0026nbsp;months and HBV DNA load greater than 10\u003csup\u003e6\u003c/sup\u003e IU/ml, started taking TBV (600\u0026nbsp;mg/day) from the 24th week of gestation and stopped TBV 12 weeks postpartum. Exclusion criteria were if patients were serologic HIV or hepatitis C or Hepatitis D virus positive, or if patients had anti-HBV treatment before the 24th week of gestation during the pregnancy, took the immunosuppressive agents during the pregnancy, and were diagnosed as any of the following diseases: gestational diabetes, arrhythmia, anemia or proteinuria. All patients were evaluated every 4 weeks from 24th week of gestation, at delivery, postpartum week (PPW) 4, 12, 24, and 52. The study was approved by the ethics committee of the First Affiliated Hospital of Xi\u0026rsquo;an Jiaotong University. Informed consent was obtained from each participant.\u003c/p\u003e \u003cp\u003eAll infants born to the chronic HBV infected mothers received combined immunoprophylaxis, 200\u0026nbsp;IU of hepatitis B immunoglobulin and 10\u0026nbsp;\u0026micro;g of recombinant HBV vaccine within 12\u0026nbsp;h postpartum, at 1 month, and at 6 months.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Ultra-deep pyrosequencing data\u003c/h2\u003e \u003cp\u003eTo evaluate the risk of HBV drug resistance generated by the short duration of TBV in pregnancy, polymerase gene analysis was conducted by using UDPS prior to (at the 24th week of gestation) and after (at the last time point of follow-up) TBV treatment. The HBV RT was amplified (697\u0026nbsp;bp) with the primers Seq2 (5\u0026prime;-TTGGCCAAAATTCGCAGTC-3\u0026prime;) and OS2 (5\u0026prime;-TCTCTGACATACTTTCCAAT-3\u0026prime;) [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. The PCR products were purified using an Omega gel extraction kit (Omega Bio-tek, USA) and quantified by a Nanodrop 1000 (Thermo Scientific, Wilmington, USA). UDPS was performed on the 454 Life Science platform (GS FLX platform, Roche).\u003c/p\u003e \u003cp\u003eThe sensitivity of UDPS on the 454 Life Science platform for detecting low-level viral variants at 0.1\u0026ndash;1% has been confirmed by the use of standard cloning methods [\u003cspan additionalcitationids=\"CR20\" citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e], the variants with prevalence larger than 1% were classified as high-confidence variants.\u003c/p\u003e \u003cp\u003eThe UDPS generated sequence reads were filtered using the following criteria: 1) mismatched base number of 5\u0026prime; primers greater than 1; 2) no undetermined bases; 3) continuous same bases greater than 8; 4) 150 bases in length or less; 5) chimera sequence. The average number of reads generated for each sample was 9766 (range: 1913 to 21909). The filtered sequence reads were aligned to their respective consensus sequences, the Smith-Waterman algorithm and mutations in corresponding sites were used to calculate Sanger sequences.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 HBV quasispecies complexity of AA\u003c/h2\u003e \u003cp\u003eThe HBV quasispecies complexity of AA level was estimated for each site using Shannon entropy (\u003cem\u003eSn\u003c/em\u003e) [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e], which can be calculated with the formula \u003cem\u003eSn\u003c/em\u003e = ๣\u0026sum;\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e(\u003cem\u003ep\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003eLn\u003cem\u003ep\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e )/Ln\u003cem\u003eN\u003c/em\u003e, where \u003cem\u003eN\u003c/em\u003e is the total number of clones and \u003cem\u003ep\u003c/em\u003e\u003csub\u003e\u003cem\u003ei\u003c/em\u003e\u003c/sub\u003e is the frequency of each clone in the viral quasispecies population [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. The mean viral complexity in each sample was calculated by the ratio of total amounts of the \u003cem\u003eSn\u003c/em\u003e at each position and the total length AA number. Mutations of rtL80, rtL82, rtV84, rtS85, rtI91, rtI169, rtV173, rtL180, rtA181, rtT184, rtA194, rtA200, rtS202, rtM204, rtV207, rtS213, rtV214, rtQ215, rtL217, rtE218, rtF221, rtL229, rtI233,rtN236, rtP237, rtN/H238, rtY245, rtM250 and rt S/C256 were analyzed in this study.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Other measurements\u003c/h2\u003e \u003cp\u003eData of age, parity, antiviral treatment history before pregnancy, HBV family history, patients HBVDNA load, HBV serum markers titer including HBsAg and HBeAg, alanine transaminase (ALT) level and creatinine kinase (CK) at 24th, 28th, 32th, 36th week of gestation, delivery and postpartum week (PPW) 4, 12, 24, and 52, corresponding safety data of infants were collected from the medical records of the hospital.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e2.5 Statistical Analysis\u003c/h2\u003e \u003cp\u003eContinuous variables were presented as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations and categorical variables were presented as counts (percentages). Paired t-tests were used to test the changes of the complex of HBV quasispecies before and after TBV treatment. The frequency of the mutations at rtM204 were compared using t-tests between patients with and without plasma HBV DNA\u0026thinsp;\u0026lt;\u0026thinsp;10\u003csup\u003e3\u003c/sup\u003e IU/mL at delivery. All tests were two-side tests and p values\u0026thinsp;\u0026lt;\u0026thinsp;0.05 were considered statistically significant. All analyses were performed with SPSS software 24.0 (SPSS Inc., Chicago, IL, USA).\u003c/p\u003e \u003c/div\u003e "},{"header":"3. Results","content":" \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Baseline maternal characteristics\u003c/h2\u003e \u003cp\u003eTotal 73 HBsAg (+) and HBV DNA load\u0026thinsp;\u0026gt;\u0026thinsp;10\u003csup\u003e6\u003c/sup\u003eIU/mL pregnant women were enrolled in the current study. Subjects accepted TBV from 24th week of gestation to PPW 12, and then were followed up at least to PPW 52. The median follow-up time was 76 weeks (range: 52\u0026ndash;152 weeks). The baseline demographics and clinical characteristics of the mothers were summarized in Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. Six pregnant women (8.2%) accepted antiviral treatment before pregnancy, 3 had interferon treatment and 3 had LAM treatment.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eDemographics and baseline characteristics\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eVariable\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eValue\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eAge, years*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e27.78\u0026thinsp;\u0026plusmn;\u0026thinsp;3.89\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eParity*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1.14\u0026thinsp;\u0026plusmn;\u0026thinsp;0.35\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePrevious use of antiviral, number (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e6 (8.22)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBV family history, number (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e32 (43.84)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALT levels, U/L*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e39.15\u0026thinsp;\u0026plusmn;\u0026thinsp;43.97\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALT\u0026thinsp;\u0026gt;\u0026thinsp;40\u0026nbsp;U/L, number (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e22 (30.14)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALT\u0026thinsp;\u0026gt;\u0026thinsp;80\u0026nbsp;U/L, number (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7 (9.59)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eALT\u0026thinsp;\u0026gt;\u0026thinsp;200\u0026nbsp;U/L, number (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e1 (1.37)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBV DNA load, Log\u003csub\u003e10\u003c/sub\u003eIU/mL*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e7.91\u0026thinsp;\u0026plusmn;\u0026thinsp;0.70\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBsAg titer, Log\u003csub\u003e10\u003c/sub\u003eIU/mL*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e4.38\u0026thinsp;\u0026plusmn;\u0026thinsp;0.47\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBeAg titer, Log\u003csub\u003e10\u003c/sub\u003es/co*\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2.45\u0026thinsp;\u0026plusmn;\u0026thinsp;1.26\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHBeAg(+), number (%)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e63 (86.30)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"2\"\u003e*The values are expressed as means\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviations for continuous variables and number of patients (percentages) for categorical variables. Abbreviations: ALT, alanine transaminase; HBeAg, hepatitis B e antigen; HBsAg, hepatitis B surface antigen; HBV, hepatitis B virus.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Dynamics of maternal HBV DNA load\u003c/h2\u003e \u003cp\u003eAs showed in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, compared to baseline, TBV treatment declined HBV DNA level (4.36\u0026thinsp;\u0026plusmn;\u0026thinsp;2.03, range 1.84 to 8.95 Log\u003csub\u003e10\u003c/sub\u003eIU/mL) in all mothers. There were 52 out of 73 (71.2%) women had serum HBV DNA load more than 10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery. Viral breakthrough was not observed during TBV treatment. After TBV withdrawal, HBV DNA levels rebounded in all mothers, and reached to a mean of 7.21\u0026thinsp;\u0026plusmn;\u0026thinsp;1.34 Log\u003csub\u003e10\u003c/sub\u003eIU/mL after 3 months of the withdrawal (PPW 24).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e3.3 Viral quasispecies complexity and NAs-resistant mutations before TBV treatment\u003c/h2\u003e \u003cp\u003eThe complexity of viral quasispecies of the samples was calculated as described in Methods section. The complexity of quasispecies (\u003cem\u003eSn\u003c/em\u003e) before TBV treatment in all patients was 0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09. The \u003cem\u003eSn\u003c/em\u003e value of treatment-na\u0026iuml;ve patients was 0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.10. The \u003cem\u003eSn\u003c/em\u003e value of the three patients who accepted LAM before pregnancy were 0.31, 0.36 and 0.36, respectively. The \u003cem\u003eSn\u003c/em\u003e value of the three patients who accepted interferon treatment before pregnancy were 0.45, 0.34 and 0.41, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe 29 known NAs-resistant mutations [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e, \u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e] were analyzed in the 73 pregnant women, At primary drug resistance mutation sites, rtM204I/V associated with resistance to LAM and TBV, also known as classical YMDD mutation, presented in 41.1% (30/73) patients before TBV treatment, 9.6% patients had mutation frequencies greater than 20%; RtA181T/V was in 5.5% (4/73) patients, which involves in the LAM, TBV and ADV shared resistance pathway; and rtN236T/A mutation, which was reported to decrease the sensitivity to TDF, presented in 53.4% (39/73) pregnant women, 5.5% patients had mutation frequencies greater than 20%. The proportions of patients with rtN236T/A mutation has no difference with those of patients with rtM204I/V mutation (41.1% \u003cem\u003evs.\u003c/em\u003e 53.4%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.136; frequencies greater than 20%: 9.6% \u003cem\u003evs.\u003c/em\u003e 5.5%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.347). At the compensatory mutation sites, 15.1% (11/73) participants had L80I/V mutation that is associated with resistance to LAM. In addition, the patients prior to TBV treatment also had other putative antiviral resistance mutations (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). However, rtI169T, rtA194T, rtV173L, rtL180M, rtL82M, rtS85A, rtV207I, rtL217R and rtS/C256Gmutations were not present before TBV treatment. Two patients who accepted LAM before pregnancy had pre-existing rtM204I mutation.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePotential NAs mutation at 29 positions of HBV reverse transcriptase analyzed in the 73 pregnant women\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"5\"\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMutations type\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eRelationship with therapy\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003eThe proportion of the patients with mutations, n (%)\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;73)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003eThe frequency of the mutations* (%)\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003ePatients with mutations frequency\u0026thinsp;\u0026gt;\u0026thinsp;20%, n (%)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePrimary resistance mutations\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertI169T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eETV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertA181T/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM, TBV, ADV, TDF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4\u0026nbsp;(5.5)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.023\u0026thinsp;\u0026plusmn;\u0026thinsp;0.020\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertT184A/C/F/G/I/L/M/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eETV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e52 (71.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.14\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e14 (19.2%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertA194T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV, TDF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertS202C/G/I\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eETV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (1.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM, ETV, TBV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30 (41.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (9.6%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertN236T/A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV, TDF\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e39 (53.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.10\u0026thinsp;\u0026plusmn;\u0026thinsp;0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e4 (5.5%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM250I/L/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e41 (56.2)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e5 (6.8%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003eCompensatory mutations\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertL80I/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e11 (15.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.01\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertV173L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertL180M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM, ETV, TBV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003ePutative NAs mutations\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertL82M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertV84M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2 (2.7)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertS85A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertI91L\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e40 (54.8)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.82\u0026thinsp;\u0026plusmn;\u0026thinsp;0.30\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e36 (49.3%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertA200V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (1.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertV207I\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertS213T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (4.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.11\u0026thinsp;\u0026plusmn;\u0026thinsp;0.16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1.4%)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertV214A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3 (4.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.01\u0026thinsp;\u0026plusmn;\u0026thinsp;0.004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertQ215P/S\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM, ADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e12 (16.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.07\u0026thinsp;\u0026plusmn;\u0026thinsp;0.08\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e2 (2.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertL217R\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertE218D\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (1.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertF221Y\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30 (41.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.29\u0026thinsp;\u0026plusmn;\u0026thinsp;0.25\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e16 (21.9)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertL229G/V/W\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e24 (32.9)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.05\u0026thinsp;\u0026plusmn;\u0026thinsp;0.06\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e1 (1.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertI233V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e30 (41.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.12\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (9.6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertP237H\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22 (30.1)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.02\u0026thinsp;\u0026plusmn;\u0026thinsp;0.02\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertN/H238D/S/T/A\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e46 (63.0)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e7 (9.6)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertY245H\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eADV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 (1.4)\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0.13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertS/C256G\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eLAM, ETV\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"5\"\u003e\u003cb\u003e*\u003c/b\u003e The prevalence of mutations were expressed as number of patients (percentages) and the mutation frequencies were expressed as mean\u0026thinsp;\u0026plusmn;\u0026thinsp;standard deviation. Abbreviations: ADV, adefovir dipivoxil; ETV, entecavir; HBV, hepatitis B virus; LAM, lamivudine; n, number; NA, nucleoside/nucleotide analogues; TBV, telbivudine; TDF, tenofovir disoproxil fumarate.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eAs showed in Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, 34.3% 25/73) patients had rtM204I mutation and 27.4% (20/73) had rtM204V mutation. Multi-base mutations combined with rtM204I/V was analyzed, rtM204I\u0026thinsp;+\u0026thinsp;rtN236T and rtM204V\u0026thinsp;+\u0026thinsp;rtN236T appeared to be the most common ones (16.4% and 17.8%, respectively). RtM204I/V\u0026thinsp;+\u0026thinsp;rtL80I/V and rtM204I\u0026thinsp;+\u0026thinsp;rtA181T/V may affect the sensitivity to LAM, TBV and ADV, they also presented but the proportions of the mutations were low (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eThe multi-base mutations combined with rtM204I/V\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"2\"\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTypes of mutation patterns\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eThe rate of the patients with mutations, n (%)\u003c/p\u003e \u003cp\u003e(n\u0026thinsp;=\u0026thinsp;73)\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003ertM204I\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I alone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e25 (34.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I\u0026thinsp;+\u0026thinsp;rtL80I/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (6.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I\u0026thinsp;+\u0026thinsp;rtA181T/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e2 (2.7)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I\u0026thinsp;+\u0026thinsp;rtL180M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I\u0026thinsp;+\u0026thinsp;rtN236T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (16.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I\u0026thinsp;+\u0026thinsp;rtI233V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e12 (16.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204I\u0026thinsp;+\u0026thinsp;rtA194T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003e\u003cb\u003ertM204V\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V alone\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e20 (27.4)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V\u0026thinsp;+\u0026thinsp;rtL80I/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e5 (6.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V\u0026thinsp;+\u0026thinsp;rtA181T/V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V\u0026thinsp;+\u0026thinsp;rtL180M\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V\u0026thinsp;+\u0026thinsp;rtN236T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e13 (17.8)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V\u0026thinsp;+\u0026thinsp;rtI233V\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e9 (12.3)\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ertM204V\u0026thinsp;+\u0026thinsp;rtA194T\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"2\"\u003eAbbreviations: n, number.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e3.4 Pre-existing HBV mutations and the TBV treatment effect\u003c/h2\u003e \u003cp\u003eAfter receiving TBV treatment during the pregnancy, 71.2% (52/73) of patients still had HBV DNA load\u0026thinsp;\u0026ge;\u0026thinsp;10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery. The complex of HBV quasispecies of these patients were not found being significantly different from that of the patients with HBV DNA load less than 10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery (0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 \u003cem\u003evs.\u003c/em\u003e 0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.353). The frequency of rtM204I was not significantly higher in patients with HBV DNA load\u0026thinsp;\u0026ge;\u0026thinsp;10\u003csup\u003e3\u003c/sup\u003eIU/mL than that of patients with HBV DNA\u0026thinsp;\u0026lt;\u0026thinsp;10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery (0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12 \u003cem\u003evs.\u003c/em\u003e 0.15\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.669), either. Among them, 75.0% patietns with rtM204I positive had HBV DNA load\u0026thinsp;\u0026ge;\u0026thinsp;10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery, which was comparable with the subjects without rtM204I (75.0% \u003cem\u003evs.\u003c/em\u003e 70.8%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.710). In addition, the patients were further divided into high mutation group (the frequency of rtM204I\u0026thinsp;\u0026ge;\u0026thinsp;20%, 10% and 5%) and low mutation group (the frequency\u0026thinsp;\u0026lt;\u0026thinsp;20%, 10% and 5%) before the TBV treatment. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e, the proportion of maternal HBV DNA load\u0026thinsp;\u0026ge;\u0026thinsp;10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery was 71.4% in the rtM204I\u0026thinsp;\u0026ge;\u0026thinsp;20% group, which was similar with that in the rtM204I\u0026thinsp;\u0026lt;\u0026thinsp;20% group (71.4% \u003cem\u003evs.\u003c/em\u003e 72.3%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.961). Similar trend was observed in groups with 10% (72.7% \u003cem\u003evs.\u003c/em\u003e 72.1%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.968) and 5% frequency of rtM204I (62.5% \u003cem\u003evs.\u003c/em\u003e 75.0%, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.325).\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e3.5 HBV mutations after the short-term TBV treatment\u003c/h2\u003e \u003cp\u003eThe impact of TBV short-time treatment to HBV mutations was analyzed among the 73 pregnant women. No change was found in the frequencies of rtM204I mutation before and after (0.34\u0026thinsp;\u0026plusmn;\u0026thinsp;0.23 \u003cem\u003evs.\u003c/em\u003e 0.32\u0026thinsp;\u0026plusmn;\u0026thinsp;0.23, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.681, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eB) the TVB treatment. Compared with the HBV quasispecies complexity at baseline, there was no significant increase after the TBV treatment (0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 \u003cem\u003evs.\u003c/em\u003e 0.41\u0026thinsp;\u0026plusmn;\u0026thinsp;0.12, \u003cem\u003eP\u003c/em\u003e\u0026thinsp;=\u0026thinsp;0.599, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eA) as well.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec14\" class=\"Section2\"\u003e \u003ch2\u003e3.6 Safety of TBV treatment\u003c/h2\u003e \u003cp\u003eTBV treatment was generally tolerated well by the mothers and their infants, there were no maternal severe adverse effects observed in this study. Mild creatinine kinase (CK) elevation (\u0026lt;\u0026thinsp;2\u0026thinsp;\u0026times;\u0026thinsp;ULN) was reported for 1 of 73 mothers (1.4%), and CK level normalized after telbivudine withdrawal (Table. S1). Among the 73 infants, there was no preterm, low birth weight, Apgar scores\u0026thinsp;\u0026lt;\u0026thinsp;10 infant, and none of them had congenital deformities. No infant was found seropositive for HBsAg, HBeAg, and HBV DNA in the follow-up.\u003c/p\u003e \u003c/div\u003e "},{"header":"4. Discussion","content":" \u003cp\u003eIn our study, we found that the overall viral quasispecies complexity was 0.40\u0026thinsp;\u0026plusmn;\u0026thinsp;0.09 and 30 of 73 patients (41.1%) had rtM204I/V positive, while 71.2% of pregnant women had serum HBV DNA load more than 10\u003csup\u003e3\u003c/sup\u003e IU/mL at delivery. It was reported that the pre-existing primary resistance mutations could reduce the susceptibility of anti-HBV monotherapy or even combined-therapy, such as rtM204I was refractory to LAM and TBV, the efficacy of the corresponding NAs could be affected[\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e]. We tested the association between the mutation frequency of rtM204I and the HBV DNA load decrease, no significant association was found in either high mutation frequency group or low mutation frequency group (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), which indicated that the pre-existing primary resistance might have no influence on the short-term TBV treatment. Besides, rtN236T/A mutation that was related to decreasing sensitivity of tenofovir disoproxil fumarate (TDF) presented in 53.4% of the pregnant women, which had no difference with the proportion of the patients with rtM204I/V mutation. This indicated that TDF with high genetic barrier to HBV resistance might not be superior to TBV for the pregnant women to prevent MTIT from the view of pre-existing primary resistance mutations.\u003c/p\u003e \u003cp\u003eWe used UDPS to detect the drug resistance mutations, which is much more sensitive than the methods of many studies used before (5\u0026ndash;20% variants detected in NAs-na\u0026iuml;ve patients)[\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. The UDPS can detect minor HBV variants and reveal the massive genetic heterogeneity by parallel amplification and detection of abundant small size sequences[\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]; moreover, it can provide longer reads than other techniques and is suitable for viral resistance studies[\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e]. As far as we know, this is the first work to evaluate the pre-existing NA resistance mutations by UDPS in a moderate sample of pregnant women with chronic HBV infection. In the present study, 41.1% of patients were rtM204I/V positive, while only 9.6% (7/73) patients had rtM204I/V frequency 20% or more. In addition, the average frequency of the mutation was 0.13\u0026thinsp;\u0026plusmn;\u0026thinsp;0.11, both of which were consistent with the previous study findings [\u003cspan additionalcitationids=\"CR11\" citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. Two previous studies conducted rtM204I/V mutation testing with sensitive methods. Kirishima et al. reported 22.2% (4/18) NA-na\u0026iuml;ve patients had rtM204I/V mutation by peptide nucleic acid mediated polymerase chain reaction clamping which could detect mutation rate as low as 0.01\u0026thinsp;\u0026minus;\u0026thinsp;0.001% [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e], and Ayres et al. detected 12.5% (3/24) pregnant women had the mutation by UDPS [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], which were lower than the rate in our study, the difference may be associated with the very limited sample sizes in the above two studies.\u003c/p\u003e \u003cp\u003eDrug-resistant HBV variants were reported to emerge in the mothers accepted short-term LAM treatment during late pregnancy [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]. Han et al. reported rtM204 mutation arose in two mothers at 22 weeks and 71 weeks of TBV treatment, respectively [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]. In our study, approximately 7 months TBV treatment was administrated in the pregnant women. No increases of the viral quasispecies complexity and the frequency of rtM204I mutation were observed, which supplemented the safety of TBV treatment in late pregnancy. Furthermore, some pregnant women had multi-base mutations combined with rtM204I/V at baseline, including rtM204I\u0026thinsp;+\u0026thinsp;rtA181T/V, rtM204I/V\u0026thinsp;+\u0026thinsp;rtL80I/V, rtM204I/V\u0026thinsp;+\u0026thinsp;rtN236T, and rtM204I/V\u0026thinsp;+\u0026thinsp;rtI233V, which may affect their sensitivity to LAM, TBV, ADV and TDF. The complexity of viral quasispecies and the frequency of rtM204I mutation had no significant increase after TBV treatment in those pregnant women; however, caution has to be taken for them to choose NAs in subsequent long-term therapy due to the drug resistance mutations.\u003c/p\u003e \u003cp\u003eIn this study, the prevalence of HBV pre-existing resistant mutants in pregnant women, the influence of the efficacy of short-term TBV treatment and the drug-resistant mutations after TBV therapy were assessed retrospectively. Although the number of subjects was moderate, a prospective cohort study with larger sample size is necessary to evaluate the relationship between the HBV mutations and the antiviral treatment effect.\u003c/p\u003e \u003cp\u003eIn conclusion, the prevalence of pre-existing HBV mutation among the pregnant women was as high as 41.1%. However, the pre-existing HBV mutation had limited influence on the efficacy of short-term TBV treatment, and TBV treatment during late pregnancy seemed not to increase the risk of emerging HBV resistant mutants.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflict of Interest Statements:\u003c/strong\u003e All the authors declare that\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp;\u0026nbsp; they have no competing interests, and\u0026nbsp;\u0026nbsp;\u0026nbsp; all authors confirm its accuracy.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval:\u003c/strong\u003e All procedures performed in this study involving human participants were in accordance with the ethical standards of the institutional and/or national research committee and with the 1964 Helsinki declaration and its later amendments or comparable ethical standards. The study protocol was approved by the ethics\u0026nbsp;committee of the First Affiliated Hospital of Xi\u0026rsquo;an Jiaotong University 2010-Lunshenkezi-No. 13).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent of publication:\u003c/strong\u003e not applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding: \u003c/strong\u003eThe study was supported by the National Natural Science Foundation of China (No. 81702119, 81770594 and No. 81670537) and the Shaanxi Province Key Research and Development Foundation (2016SF-158 and 2017SF-043).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data:\u003c/strong\u003e The data in the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors' contributions: \u003c/strong\u003eTC, YH, YZ and JZ conceived of the presented idea. JW, JL, LJ, NY and QY acquired data in the study. YY, TY, CH and JW analyzed data. JW drafted the paper, and all authors discussed the results and contributed to the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgments:\u003c/strong\u003e We thank all individuals who have participated in this study. We thank Prof. Gang Shi for their support and help to this study.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eTerrault NA, Lok ASF, McMahon BJ, Chang KM, Hwang JP, Jonas MM, Brown RS, Jr., Bzowej NH, Wong JB: \u003cstrong\u003eUpdate on Prevention, Diagnosis, and Treatment of Chronic Hepatitis B: AASLD 2018 Hepatitis B Guidance\u003c/strong\u003e. \u003cem\u003eClinical liver disease \u003c/em\u003e2018, \u003cstrong\u003e12\u003c/strong\u003e(1):33-34.\u003c/li\u003e\n\u003cli\u003e\u003cstrong\u003eEASL 2017 Clinical Practice Guidelines on the management of hepatitis B virus infection\u003c/strong\u003e. \u003cem\u003eJ Hepatol \u003c/em\u003e2017, \u003cstrong\u003e67\u003c/strong\u003e(2):370-398.\u003c/li\u003e\n\u003cli\u003eSarin SK, Kumar M, Lau GK, Abbas Z, Chan HL, Chen CJ, Chen DS, Chen HL, Chen PJ, Chien RN\u003cem\u003e et al\u003c/em\u003e: \u003cstrong\u003eAsian-Pacific clinical practice guidelines on the management of hepatitis B: a 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font-family: Helvetica; color: rgb(0, 0, 0);\"\u003eTable S1.\u003c/span\u003e\u003c/strong\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e\u003cspan style=\"line-height: 200%;\"\u003e\u0026nbsp;\u003cstrong\u003eAdverse events reported in current study*\u003c/strong\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n\u003ctable style=\"border-collapse:collapse;border:none;\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border-top: 1.5pt solid windowtext;border-left: none;border-bottom: 1pt solid windowtext;border-right: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e\u003cstrong\u003eAdverse event\u0026nbsp;\u003c/strong\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border-top: 1.5pt solid windowtext;border-left: none;border-bottom: 1pt solid windowtext;border-right: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e\u003cstrong\u003eNumber (%)\u003c/strong\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eGastrointestinal symptom\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e5 (6.85%)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e\u0026nbsp; Nausea\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e1 (1.37)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e\u0026nbsp; Emesis\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e1 (1.37)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;text-indent:11.0pt;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eDiarrhea\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e1 (1.37)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;text-indent:11.0pt;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eflatulence\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e1 (1.37)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;text-indent:11.0pt;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eDyspepsia\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e1 (1.37)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eFatigue\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e2 (2.74)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eDizziness\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e1 (1.37)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: 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delivery\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e35 (47.95)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eThreatened abortion\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border: none;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e11 (15.07)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 208.3pt;border-top: none;border-right: none;border-left: none;border-image: initial;border-bottom: 1.5pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003eProlonged Labor\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 207pt;border-top: none;border-right: none;border-left: none;border-image: initial;border-bottom: 1.5pt solid windowtext;padding: 0in 5.4pt;vertical-align: top;\"\u003e\n \u003cp style='margin:0in;margin-bottom:.0001pt;text-align:center;font-size:14px;font-family:\"Times New Roman\",serif;'\u003e\u003cspan style=\"color: rgb(0, 0, 0);\"\u003e\u003cspan style=\"font-size: 13px;\"\u003e\u003cspan style=\"font-family: Helvetica;\"\u003e4 (6.25)\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp style='margin:0in;margin-bottom:.0001pt;text-align:justify;font-size:14px;font-family:\"Times New Roman\",serif;line-height:200%;'\u003e\u003cspan style=\"font-size: 13px; line-height: 200%; font-family: Helvetica; color: rgb(0, 0, 0);\"\u003e*Number (percentages) of patients with adverse events were reported. Abbreviations: CK, creatinine kinase.\u003c/span\u003e\u003c/p\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"HBV; Ultra-deep pyrosequencing; rtM204I/V; telbivudine; mutation.","lastPublishedDoi":"10.21203/rs.3.rs-44747/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-44747/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eHBV resistant mutants in treatment-naïve patients may lead to antiviral treatment failure. It’s not clear if HBV resistant mutants present in the pregnant women before the antiviral treatment and the influence of the pre-existing resistant mutants on the short-term Telbivudine (TBV) therapy during the late pregnancy.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eMethod: \u003c/strong\u003eWe enrolled 73 pregnant women with high HBV DNA load and TBV treatment during the pregnancy from 2012 to 2015 in this retrospective study. All subjects were followed at least 52 weeks postpartum. The UDPS was used to detect the HBV mutations before and after the TBV treatment.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults: \u003c/strong\u003eBefore TBV treatment, the complexity of HBV quasispecies of all subjects was 0.40± 0.09. At primary drug resistance mutation sites, 41.1% (30/73) and 53.4% (39/73) subjects had rtM204I/V and rtN236T/A detected, respectively; 9.6% (7/73) patients had more than 20% frequency mutation of rtM204I/V, which was also similar with high frequency of rtN236T/A mutation (41.1% \u003cem\u003evs.\u003c/em\u003e 53.4%, \u003cem\u003eP \u003c/em\u003e= 0.136; frequencies \u0026gt; 20%: 9.6% \u003cem\u003evs.\u003c/em\u003e 5.5%, \u003cem\u003eP \u003c/em\u003e= 0.347). After TBV treatment, 71.2% (52/73) subjects still had HBV DNA load ≥ 10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery. Among them, 75.0% patietns with rtM204I positive had HBV DNA load ≥ 10\u003csup\u003e3\u003c/sup\u003eIU/mL at delivery, which was comparable with the subjects without rtM204I (75.0% \u003cem\u003evs.\u003c/em\u003e 70.8%, \u003cem\u003eP\u003c/em\u003e = 0.710). No changes were found in the frequencies and the complexity of HBV quasispecies of rtM204I mutation after the TVB treatment.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusion: \u003c/strong\u003eThe prevalence of pre-existing drug resistant mutations among the pregnant women was high using UPDS. However, the pre-existing HBV mutation had limited influence on the efficacy of short-term TBV treatment, and TBV treatment during late pregnancy seemed not to increase the risk of emerging HBV resistant mutants.\u003c/p\u003e","manuscriptTitle":"High prevalence of pre-existing HBV polymerase mutations in pregnant women do not limit the telbivudine treatment efficacy","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2020-07-24 19:06:55","doi":"10.21203/rs.3.rs-44747/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"21b8cb9c-f150-4ac4-8edd-f5d1ffd12a49","owner":[],"postedDate":"July 24th, 2020","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[{"id":198583,"name":"Infectious Diseases"}],"tags":[],"updatedAt":"2020-08-24T23:33:15+00:00","versionOfRecord":[],"versionCreatedAt":"2020-07-24 19:06:55","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-44747","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-44747","identity":"rs-44747","version":["v1"]},"buildId":"GqpaHPwrfC8PjnIFayRh5","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}