Abstract
The developmental hazard screening of oligonucleotide therapeutics (ONTs) presents challenges due to their frequent lack of pharmacology in nonclinical species and embryofetal exposure is presumed to be limited in vivo . This study demonstrates that direct culture in media containing mipomersen, a 2’-O-methoxyethyl phosphorothioated antisense oligonucleotide (ASO), results in dose-responsive morphological changes in rat and rabbit whole embryo culture (WEC). Automated miRNAscope in situ hybridization was used to confirm dose-dependent embryonic exposure and visualize the distribution pattern of mipomersen in the embryo and extra-embryonic membranes, suggesting that ONTs may enter the umbilical vasculature and pass into embryo circulation. Neither microinjections nor assisted transfections were required to achieve embryonic exposure. These findings support the utility of WEC as a new approach method (NAM) for developmental hazard identification of ONTs. WEC could complement or partially replace in vivo studies, reducing animal use and required test material amounts, while enabling robust developmental hazard identification for ONTs. This work informs future safety assessment strategies and regulatory guidance for ONTs.
Full text
1,503 characters
· extracted from
oa-doi-fallback
· click to expand
Abstract
The developmental hazard screening of oligonucleotide therapeutics (ONTs) presents challenges due to their frequent lack of pharmacology in nonclinical species and embryofetal exposure is presumed to be limited in vivo. This study demonstrates that direct culture in media containing mipomersen, a 2’-O-methoxyethyl phosphorothioated antisense oligonucleotide (ASO), results in dose-responsive morphological changes in rat and rabbit whole embryo culture (WEC). Automated miRNAscope in situ hybridization was used to confirm dose-dependent embryonic exposure and visualize the distribution pattern of mipomersen in the embryo and extra-embryonic membranes, suggesting that ONTs may enter the umbilical vasculature and pass into embryo circulation. Neither microinjections nor assisted transfections were required to achieve embryonic exposure. These findings support the utility of WEC as a new approach method (NAM) for developmental hazard identification of ONTs. WEC could complement or partially replace in vivo studies, reducing animal use and required test material amounts, while enabling robust developmental hazard identification for ONTs. This work informs future safety assessment strategies and regulatory guidance for ONTs.
Competing Interest Statement
All authors are employed by a company, GSK, that develops oligonucleotide therapies. Additionally, Joel Parry is the European Federation of Pharmaceutical Industries and Associations (EFPIA) Lead on ICH S13 Expert Working Group.
Text is read by the "Ask this paper" AI Q&A widget below.
Extraction quality varies by source — PMC NXML preserves structure
cleanly, OA-HTML may include some navigation residue, and OA-PDF can
have broken hyphenation. The publisher copy
(via DOI)
is the canonical version.