Feasibility of Atezolizumab in Combination with Chemotherapy for Children with Relapsed or Refractory Solid Tumors

Feasibility of Atezolizumab in Combination with Chemotherapy for Children with Relapsed or Refractory Solid Tumors | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL Pediatric Blood & Cancer This is a preprint and has not been peer reviewed. Data may be preliminary. 7 June 2025 V1 Latest version Share on Feasibility of Atezolizumab in Combination with Chemotherapy for Children with Relapsed or Refractory Solid Tumors Authors : Matthew E. Campbell 0009-0000-4497-7364 , Sonja Stutzman , Sharon Primeaux , Deseray Sida , Minjae Lee 0000-0002-4329-506X , Avanthi T. Shah , Arhanti Sadanand 0000-0002-7780-1688 , … Show All … , Elizabeth Sokol 0000-0002-1787-6901 , Natalie Collins , Brian Turpin 0000-0002-3658-5659 , Shoba Navai 0000-0003-1220-2788 , Catherine Albert , Theodore Laetsch 0000-0002-8497-3138 , Dinesh Rakheja 0000-0001-6888-7902 , Kenneth Chen 0000-0003-2304-4631 , David Gerber , and Andrew Koh [email protected] Show Fewer Authors Info & Affiliations https://doi.org/10.22541/au.174928338.87860840/v1 Published Pediatric Blood & Cancer Version of record Peer review timeline 505 views 280 downloads Contents Abstract Supplementary Material Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract Background : Combining immune checkpoint inhibitors (ICI) with chemotherapy may improve treatment response in children with solid tumors. We sought to determine the feasibility of combining v incristine, i rinotecan, and t emozolomide with the ICI a tezolizumab in children with relapsed or refractory s olid tumors (VITAS). Methods: Patients ≥ 6 months and ≤ 18 years old with a relapsed or refractory solid tumor, no prior ICI, and evaluable disease per RECIST v1.1 were eligible for the Phase I cohort (NCT04796012). Patients received atezolizumab 15 mg/kg on day 1, vincristine 1.5 mg/m 2 on day 1, irinotecan 50 mg/m 2 on days 1-5, and temozolomide 100 mg/m 2 on days 1-5 in 21-day cycles. Primary endpoint was the number of patients with dose-limiting toxicities (DLT) in the first two cycles of therapy. Results : Six patients (median age: 14 years) with rhabdomyosarcoma (n=3), osteosarcoma (n=2), and Ewing sarcoma (n=1) received therapy and were evaluable for toxicity. Patients received a median of 7 (range: 2 to 20) cycles of treatment. No patients experienced a DLT. One patient experienced Grade 2 immune-related colitis. Four patients experienced Grade ≥ 3 adverse events (decreased neutrophil count, febrile neutropenia, weight loss, anorexia). One patient with rhabdomyosarcoma had a sustained partial response through 16 cycles. One patient with relapsed pulmonary osteosarcoma has ongoing stable disease through 20 cycles. Conclusions : Atezolizumab combined with vincristine, irinotecan, and temozolomide was feasible and well tolerated in children with solid tumors. Efficacy of this regimen is now being assessed in relapsed and refractory rhabdomyosarcoma in an ongoing Phase II cohort. INTRODUCTION Children with relapsed or refractory solid tumors have poor outcomes and limited treatment options. While immune checkpoint inhibitor (ICI) therapy has revolutionized the care of multiple adult cancers, it has shown limited monotherapy efficacy in pediatric solid tumors 1-3 . Potential reasons for this disparity include lower mutational burden in pediatric tumors, immature immune systems in pediatric populations, and distinct gut microbiomes 4-11 . Combining ICI with chemotherapy may improve these outcomes. Cytotoxic chemotherapy exposes tumor antigens and can create an immunogenic tumor microenvironment 12-17 . Commonly used chemotherapies also induce immune-mediated anti-tumor responses that, in turn, may be amplified by ICI 18 . Indeed, in multiple adult cancers, the combination of conventional chemotherapy with ICI has improved treatment response and has become standard of care 19 20 21 22,23 . It remains unknown whether that success can be extended to a pediatric population. Atezolizumab is an ICI that blocks PD-L1 interaction with PD-1 and B7-1 on T cells to enhance tumor-specific responses and anti-tumor activity 24,25 . Atezolizumab has demonstrated efficacy across multiple malignancies (both as monotherapy and in combination with chemotherapy), earning FDA approval for treatment of non-small cell lung cancer, small-cell lung cancer, hepatocellular carcinoma, and melanoma. Adverse reactions to atezolizumab include infusion-related reactions and various immune-related toxicities; these events have generally been manageable through treatment interruption or direct management of adverse reactions. When used in combination with chemotherapy in adults, toxicities have remained consistent with those of individual agents 21,26,27 . Although not approved for pediatric use, atezolizumab is well-tolerated in children at 15mg/kg (maximum 1,200 mg) IV every 21 days with a toxicity profile similar to that observed in adults 2 . The combination of vincristine, irinotecan, and temozolomide (VIT) is well-tolerated and has clinical activity in multiple tumor types, including relapsed or refractory rhabdomyosarcoma 28-30 . Further, VIT may promote anti-tumor immune responses through selectively depleting inhibitory regulatory T cells, increasing tumor mutational burden, and increasing tumor antigen presentation 12-17 . VITAS (NCT04796012) is a Phase I/II open-label, single arm, multi-center study designed to assess the safety, feasibility, and efficacy of combining VIT with the ICI atezolizumab in children with relapsed or refractory solid tumors. Herein, we report the Phase I feasibility results and the recommended Phase II dosing of this novel combination. Objectives The primary objective of the VITAS Phase I cohort was to determine the feasibility of administering vincristine, irinotecan, temozolomide, and atezolizumab simultaneously in children with relapsed or refractory solid tumors. The feasibility endpoint was defined as the number of patients with dose-limiting toxicities (DLT) in the first two cycles of therapy. Patient eligibility Patients aged ≥ 6 months and ≤ 18 years with a relapsed or refractory solid tumor (after at least one line of systemic therapy) were eligible for the Phase I feasibility cohort. Additional eligibility criteria included evaluable disease per RECIST v1.1; available tumor specimen (either from initial diagnosis or from a recurrence) to determine PD-L1 status; and performance status ≥ 50 per Lansky Performance Status (patients < 16 years old) or Karnofsky Performance Status (patients ≥ 16 years old). Patients must have fully recovered from the acute toxic effects of all prior therapy and could not have received myelosuppressive therapy within 21 days of starting treatment, non-myelosuppressive therapy within 7 days of start of protocol therapy, monoclonal antibodies within 3 half-lives of protocol therapy, cellular therapies within 28 days of protocol therapy, or major surgical procedure within 30 days of start of protocol therapy. Organ function requirements included absolute neutrophil count ≥ 1000/mm 3 , absolute lymphocyte count ≥ 500/mm 3 , hemoglobin ≥ 9 g/dL, platelets ≥ 75,000/mm 3 , total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN), ALT and ALT ≤ 2.5 x ULN, serum albumin ≥ 25 g/L, creatinine ≤ 1.5 x ULN for age or a creatinine clearance ≥ 70 mL/min/1.73m 2 , INR or aPTT ≤ 1.5 x ULN, and left ventricular ejection fraction ≥ 50% or shortening fraction ≥ 30%. Exclusion criteria included pregnancy or breastfeeding, known allergy or hypersensitivity to any component of the study medications, history of severe allergic anaphylactic reaction to chimeric or humanized antibodies or fusion proteins, uncontrolled intercurrent illnesses including ongoing or untreated infections, prior ICI therapy, ongoing treatment with other investigational agents, other concomitant anti-cancer agents, systemic immunostimulatory agents, and diagnosis of an autoimmune disorder. Study design and treatment schema This study (NCT04796012) was opened at five pediatric cancer centers. UT Southwestern was the coordinating center. The study was approved by the UT Southwestern Single Institutional Review Board (IRB; STU-2021-0606) for all sites. Written informed consent and assent were obtained according to institutional guidelines. Treatment was administered in 21-day cycles ( Figure 1 ). Patients received atezolizumab 15 mg/kg (maximum 1,200 mg) on day 1 of each 21-day cycle, vincristine 1.5 mg/m 2 (maximum 2 mg) on day 1, irinotecan 50 mg/m 2 IV on days 1-5, and temozolomide 100 mg/m 2 on days 1-5 (PO or IV). Subsequent cycles were administered if the patient had no clinical or radiographic evidence of progressive disease, adequate laboratory parameters (including unsupported platelet count ≥75,000/mm 3 and absolute neutrophil count ≥750/mm 3 ), and recovery from treatment-related toxicities to an acceptable grade per protocol. If patients experienced an atezolizumab-related adverse event requiring active treatment with steroids at a dosing equivalent of ≥ prednisone 10 mg/day, atezolizumab was withheld and the other study drugs could be administered. Patients were removed from study if atezolizumab needed to be held for 2 consecutive cycles. Patients could receive local therapy (radiation or surgery) to non-target lesions after at least four cycles of atezolizumab provided it did not interfere with assessment of tumor target lesions. Patients did not receive antibiotic prophylaxis for irinotecan-associated diarrhea given that antibiotics are known to impact the efficacy of immune checkpoint inhibitor therapy 31 . The protocol provided guidance for the management of irinotecan-associated diarrhea with the specific recommendation to use atropine daily while administering irinotecan, regardless of patient symptoms. All patients received oral trimethoprim-sulfamethoxazole for Pneumocystis jirovecii prophylaxis while on protocol therapy. Patients could receive treatment on study for up to 2 years. Subjects were removed from protocol therapy for disease progression, intercurrent illness that prevented further administration of treatment, unacceptable adverse event(s), patient decision to withdraw from the study, or changes in the patient’s condition that rendered the patient ineligible for further treatment in the judgement of the investigator. Assessments Common Terminology Criteria for Adverse Events (CTCAE) version 5.0 was used for toxicity grading. DLT evaluation occurred from day 1 of cycle 1 until day 1 of cycle 3 or 30 days from day 1 of cycle 2, whichever was earlier. Non-hematological DLTs were defined as any toxicity that resulted in a delay of a subsequent cycle by > 14 days or withholding atezolizumab ≥ 28 days, except allergic reactions, and Grade ≥3 toxicity possibly, probably or definitely attributable to the investigational regimen. Specific exceptions included Grade 3 nausea and vomiting ≤ 3 days duration, Grade 3 mucositis or stomatitis ≤ 3 days duration, Grade 3 fever, Grade 3 infection, or Grade 3 hypophosphatemia, hypokalemia, hypocalcemia, or hypomagnesemia responsive to supplementation within 7 days. Hematological DLTs were defined as Grade 4 neutropenia for > 7 days, Grade 4 anemia (unexplained by underlying malignancy), platelet count 14 days between treatment cycles. Myeloid growth factors could not be used in cycle 1, except in cases of documented infection. Guidance on the identification and treatment of immune related adverse events (irAEs) was outlined in the study protocol. Six patients were identified for accrual at the initial dose level. The treatment regimen was to be deemed feasible, and the recommended Phase 2 dose (RP2D) would be established if no more than 2 patients developed DLTs. If more than 2 patients developed a DLT, then doses would be de-escalated, depending on the types and attributions of toxicities exhibited. The feasibility cohort would then be extended until 6 patients were accrued at the same dose level. Treatment response was determined per RECIST v1.1. Tumor assessments were performed within the last week of cycles 2, 4, 8, and every 4 cycles thereafter. PD-L1 immunohistochemistry was performed in a central laboratory using the 22c3 antibody and interpreted by a board-certified pathologist (DR). Partial or complete membranous staining of any intensity was considered positive and PD-L1 positivity was calculated as a Combined Positive Score (CPS), defined previously as the sum of positive viable tumor cells and positive mononuclear inflammatory cells divided by the total number of viable tumor cells and the fraction then multiplied by 100 32 . A CPS score ≥1 was considered positive but was not required for eligibility and was performed retrospectively after enrollment. Statistical Considerations Demographic and clinical characteristics were summarized using descriptive statistics, including median and range for continuous variables and proportions and frequencies for categorical variables. RESULTS Eight patients consented to participate and were screened ( Figure 1 ). Two patients were excluded: one patient started emergent off-protocol chemotherapy, and one patient did not meet eligibility criteria. The remaining six patients received therapy per protocol and were evaluable for toxicity. The median age was 14 years (range 8 to 16), and 3 patients (50%) were female ( Table 1 ). Three patients had rhabdomyosarcoma, two patients had osteosarcoma, and one patient had Ewing sarcoma. Patients had received a median of 3 (range 1-3) prior lines of systemic therapy. Patients received a median of 7 cycles (range 2-20). One patient stopped therapy after day 1 of cycle 8 due to intolerable toxicity (Grade 2 nausea, Grade 3 anorexia). One patient received myeloid growth factor after cycle 1, at least once during protocol therapy. Four patients received systemic antibiotics for fever at least once during protocol therapy. One patient received oral vancomycin for Clostridium difficile infection. Safety All 6 treated patients received at least two cycles of protocol therapy and were included in toxicity analysis. No patients experienced a DLT. Overall, 5 patients (83%) experienced Grade 3 or 4 adverse events (AEs, Table 2) , including decreased neutrophil count (n=4, 67%), decreased white blood cell count (n=1, 17%), febrile neutropenia (n=1, 17%), anorexia (n=1, 17%), and weight loss (n=1, 17%)). No patient had a treatment delay of more than 7 days due to Grade 3 or 4 toxicities. The most common toxicities of all grades were nausea (n=6, 100%), vomiting (n=5, 86%), diarrhea (n=5, 86%), anorexia (n=5, 86%), and neutrophil count decreased (n=4, 67%). All toxicities of all grades are shown in Table S1 . One patient developed Grade 2 immune-related colitis in cycle 4 that was confirmed on biopsy and pathologic review. This patient had resolution of diarrhea within 14 days, did not require treatment with steroids, and did not have treatment delay due to colitis. No patients died on study from treatment-related toxicity. Efficacy All 6 enrolled patients received at least two cycles of protocol therapy and were eligible for assessment of disease response per RECIST v1.1 ( Figure 2 ). One patient with recurrent Ewing sarcoma of the bony pelvis had an incomplete response of evaluable disease with decreased PET avidity after 4 cycles of VITAS therapy. He subsequently received radiation to the site of disease while continuing protocol therapy and had complete resolution of PET avidity. The patient elected to come off protocol therapy after day 1 of cycle 8 due to intolerable side effects (nausea, anorexia). He experienced disease recurrence six months after stopping therapy. Two patients had osteosarcoma with measurable disease. One patient with paraspinal disease had progressive disease after two cycles of therapy. The other patient had unresectable pulmonary disease and has had stable disease through 20 cycles and remains on therapy at the time of this report. Three patients had rhabdomyosarcoma with measurable disease. One patient with FOXO1- fusion positive rhabdomyosarcoma with multiple sites of disease had stable disease after two cycles of therapy but developed progressive disease after four cycles of therapy. One patient with FOXO1-fusion positive rhabdomyosarcoma with paranasal and orbital disease had progressive disease after two cycles of therapy. One patient with MYOD1 -mutant spindle cell/sclerosing rhabdomyosarcoma had a sustained partial response through 16 cycles of therapy but had disease progression after 20 cycles of therapy ( Figure 3 ). She received radiation to non-target lesions after 4 cycles of chemotherapy. The PD-L1 CPS scores for all patients are listed in Table 3 . Two patient tumors were PD-L1 positive: patient 9832-4 with pulmonary metastatic osteosarcoma with stable disease through 20 cycles had a CPS score of 5, and patient 9832-2 with MYOD1 -mutant spindle cell/sclerosing rhabdomyosarcoma with a sustained partial response through 16 cycles had a CPS score of 9. All other patients had a CPS score < 1. DISCUSSION ICI monotherapy has limited efficacy in pediatric cancers. Combining ICI with chemotherapy is supported by strong biologic rationale and efficacy in numerous adult cancers. This study demonstrated the safety and feasibility of combining VIT with atezolizumab for children and adolescents with relapsed or refractory solid tumors. No patients experienced DLTs. While most patients experienced Grade ≥3 toxicity, all adverse events were anticipated, and importantly, none resulted in a treatment delay more than 7 days. All patients experienced nausea and most experienced diarrhea. This was anticipated and monitored closely. Patients did not receive antibiotic prophylaxis for irinotecan-associated diarrhea given that antibiotics are known to impact the efficacy of ICI therapy. Antibiotic prophylaxis is standard of care when administering irinotecan, but safety of its use without prophylaxis has previously been demonstrated 33 . No patients experienced Grade 3 or 4 diarrhea, and no patients had treatment delays due to diarrhea. One patient experienced autoimmune toxicity (colitis) that resolved without steroids. As such, patients receiving this combination in Phase II will not receive antibiotic prophylaxis for irinotecan-associated diarrhea. One patient with rhabdomyosarcoma had a sustained partial response through 16 cycles. One patient with osteosarcoma has had stable disease through 20 cycles of therapy. One patient with evaluable Ewing sarcoma did not experience disease progression while on protocol therapy. Interestingly, the patients with rhabdomyosarcoma and osteosarcoma who experienced apparent clinical benefit both had a PD-L1 CPS score > 1. While anecdotal, these clinical data suggest potential value in further exploring the efficacy of this treatment combination. A Phase II rhabdomyosarcoma efficacy cohort was planned a priori , as the effectiveness of VIT in treating relapsed rhabdomyosarcoma in children has been well assessed, allowing for estimation of a baseline response rate 28-30 . Further, there is evidence that the PD-1/PD-L1 signaling axis is biologically relevant in rhabdomyosarcoma 34,35 . Hence, our Phase II rhabdomyosarcoma efficacy cohort is currently enrolling patients. Osteosarcoma and Ewing sarcoma Phase II cohorts also merit considerations for future trials. These results also highlight the importance of ensuring an adequate number of study patients have PD-L1(+) tumors. Indeed, our study requires at least 8 of 17 patients in the rhabdomyosarcoma Phase II cohort to have PD-L1(+) tumors for adequate subset analysis. Future correlative studies of patient tumor, blood, and stool may also lend insights into characteristics associated with response to therapy. Our study has several limitations. VITAS was a histology agnostic Phase I study with a limited sample size. While the partial response observed in a patient with rhabdomyosarcoma and the durable stable disease observed in patients with Ewing sarcoma and osteosarcoma were encouraging, we cannot draw any definitive conclusions regarding treatment efficacy overall or in disease-specific cohorts. Future Ewing sarcoma or osteosarcoma Phase II expansion cohorts could provide valuable insight. Finally, the youngest patient was 8 years old and most patients were adolescents, which to some extent limits assessment of toxicities that may be observed in younger children (as our study was open to children as young as 6 months of age). ICIs and their combination with chemotherapy have so far had a limited role in the treatment of pediatric cancers, primarily restricted to several lymphoma subtypes and solid tumors with high mutation burden or mismatch-repair deficiency 36 . To our knowledge, this is the first trial testing the specific combination of VIT, a safe and widely used chemotherapy backbone for relapsed solid tumors, with ICI therapy. This is also the first such trial with a specific focus on treatment effect in RMS. In conclusion, combining atezolizumab with VIT to treat children with relapsed solid tumors was feasible at previously established doses with an expected and manageable toxicity profile. The combination showed promising disease control in one patient with rhabdomyosarcoma, one patient with Ewing sarcoma, and one with osteosarcoma. A more thorough assessment of anti-tumor activity is ongoing in a Phase II rhabdomyosarcoma cohort . Acknowledgements We acknowledge Genentech for provision of atezolizumab and Children’s Cancer Fund, Wipe Out Kids Cancer, the University of Texas Southwestern Medical Center and Children’s Health Pediatric and Cellular ImmunoTherapeutics Program, and Alex’s Lemonade Stand Center of Excellence in Childhood Cancer Drug Development and Clinical Pharmacology for their funding support. Conflict of Interest Statement AYK is co-founder of Aumenta Biosciences. AYK receives research funding from Novartis. DEG reports consulting fees from Catalyst Pharmaceuticals; U.S. patent 11,747,345; pending patents 17/045,482, 18/504,868, 63/386,387, 63/382,972, and 63/382,257; research funding from AstraZeneca, Karyopharm, and Novocure; participating in advisory boards for Astra-Zeneca, Daiichi-Sankyo, Elevation Oncology, GSK, Janssen Scientific Affairs, Jazz Pharmaceuticals, Regeneron Pharmaceuticals, and Sanofi; stock shares in Gilead; and serving as co-founder and Chief Medical Officer of OncoSeer Diagnostics, Inc. TWL reports consulting/advisory boards for Advanced Microbubbles, AI Therapeutics, Bayer, GSK, ITM Oncologics, and Jazz Pharmaceuticals, and research support from Bayer, Pfizer, Eli Lilly, and Exelixis. Data Availability Statement Research data are not shared. References 1. Geoerger B, Kang HJ, Yalon-Oren M, et al. 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Venkatramani R, Malogolowkin M, Davidson TB, May W, Sposto R, Mascarenhas L. A phase I study of vincristine, irinotecan, temozolomide and bevacizumab (vitb) in pediatric patients with relapsed solid tumors. PLoS One. 2013;8(7):e68416.34. Uehara S, Nakahata K, Kawatsu M, et al. The Pd-L1 Expression Increases after Consecutive Multimodal Therapies in Neuroblastoma. Pediatric Blood & Cancer. 2015;62:S334-S335.35. Liu J, Liu P, Gong F, Tian Y, Zhao X. Case Report: A PD-L1-Positive Patient With Pleomorphic Rhabdomyosarcoma Achieving an Impressive Response to Immunotherapy. Front Immunol. 2022;13:815598.36. Ciurej A, Lewis E, Gupte A, Al-Antary E. Checkpoint Immunotherapy in Pediatric Oncology: Will We Say Checkmate Soon? Vaccines (Basel). 2023;11(12). Legend List Figure 1. Trial Design: (A) Phase I/II design with cohort recruitment, treatment plan, and disease evaluation plan. (B) Phase I trial profile accounting for all patients consented to study. CR, complete response. PR, partial response. SD, stable disease. Figure 2. Swimmer’s Plot of 6 patients treated on study, with timing of events from day 1 of treatment. Patient 9832-1 is represented as Stable Disease but had Evaluable Disease that was Non-Complete Response/Non-Progressive Disease. Figure 3. Serial CT Chest images of patient 9832-2 with MYOD1-mutant spindle cell/sclerosing RMS who had a sustained PR to VITAS therapy through 16 cycles. Imaging at baseline (A) and after 2 cycles of protocol therapy (B). CT, Computed Tomography. RMS, Rhabdomyosarcoma. PR, partial response. Supplementary Material File (vitas feasibility manuscript tables 06_06_25.docx) Download 21.84 KB File (vitas figure 3.tif) Download 4.03 MB Information & Authors Information Version history V1 Version 1 07 June 2025 Peer review timeline Published Pediatric Blood & Cancer Version of Record 12 Sep 2025 Published Copyright This work is licensed under a Non Exclusive No Reuse License. Collection Pediatric Blood & Cancer Keywords immunotherapy pediatric oncology phase i clinical trials sarcomas solid tumors Authors Affiliations Matthew E. Campbell 0009-0000-4497-7364 The University of Texas Southwestern Department of Pediatrics View all articles by this author Sonja Stutzman The University of Texas Southwestern Department of Pediatrics View all articles by this author Sharon Primeaux The University of Texas Southwestern Department of Pediatrics View all articles by this author Deseray Sida The University of Texas Southwestern Department of Pediatrics View all articles by this author Minjae Lee 0000-0002-4329-506X The University of Texas Southwestern O'Donnell School of Public Health View all articles by this author Avanthi T. Shah The University of Texas Southwestern Department of Pediatrics View all articles by this author Arhanti Sadanand 0000-0002-7780-1688 The University of Texas Southwestern Department of Pediatrics View all articles by this author Elizabeth Sokol 0000-0002-1787-6901 Ann & Robert H Lurie Children's Hospital of Chicago View all articles by this author Natalie Collins Dana-Farber/Boston Children's Cancer and Blood Disorders Center View all articles by this author Brian Turpin 0000-0002-3658-5659 Cincinnati Children's Hospital Medical Center View all articles by this author Shoba Navai 0000-0003-1220-2788 Baylor College of Medicine Department of Pediatrics View all articles by this author Catherine Albert University of Washington Department of Pediatrics View all articles by this author Theodore Laetsch 0000-0002-8497-3138 University of Pennsylvania Department of Pediatrics View all articles by this author Dinesh Rakheja 0000-0001-6888-7902 The University of Texas Southwestern Department of Pediatrics View all articles by this author Kenneth Chen 0000-0003-2304-4631 The University of Texas Southwestern Department of Pediatrics View all articles by this author David Gerber The University of Texas Southwestern Medical Center Department of Internal Medicine View all articles by this author Andrew Koh [email protected] The University of Texas Southwestern Department of Pediatrics View all articles by this author Metrics & Citations Metrics Article Usage 505 views 280 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Matthew E. Campbell, Sonja Stutzman, Sharon Primeaux, et al. Feasibility of Atezolizumab in Combination with Chemotherapy for Children with Relapsed or Refractory Solid Tumors. Authorea . 07 June 2025. DOI: https://doi.org/10.22541/au.174928338.87860840/v1 If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download. For more information or tips please see 'Downloading to a citation manager' in the Help menu . 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