Samidorphan negative in a standard genotoxicity battery
“SAM was negative in a complete and adequate battery of genetic toxicology assays.”
✓ VerifiedFDA multi-discipline review, p. 320Source ↗
Carcinogenicity
Samidorphan: up to 95-week rat and 6-month rasH2 mouse studies, no tumors
“SAM is also non-carcinogenic as it did not induce tumors in male and female rats administered SAM for up to 95 weeks at exposures which are approximately 32 and 237 times the MRHD based on AUC, respectively and did not induce tumors in rasH2 transgenic mice administered SAM for 6-months.”
✓ VerifiedFDA multi-discipline review, p. 320Source ↗
Reproductive & developmental
Samidorphan rat EFD: reduced fetal weight, skeletal variations, slight malformation increase at maternally toxic doses >248x MRHD
“SAM administration to pregnant rats during the period of organogenesis resulted in decreased fetal weights, increased skeletal variations, and a slight increase in total malformations at doses that were maternally toxic and greater than 248 times the MRHD based on AUC.”
✓ VerifiedFDA multi-discipline review, p. 321Source ↗
Safety pharmacology
Samidorphan and RDC-9986 not significant hERG blockers; no cardiovascular or respiratory effects in dogs at 20x MRHD
“In safety pharmacology studies, SAM and metabolite RDC-9986 were not significant hERG channel blockers, and SAM did not have any significant adverse effects on cardiovascular or respiratory parameters in dogs at doses which are 20 times the maximum recommended human dose (MRHD) of 10 mg SAM based on AUC.”
✓ VerifiedFDA multi-discipline review, p. 320Source ↗
Not genotoxic overall: Ames negative; in vitro chromosome aberration positive without (not with) metabolic activation; rat micronucleus and comet negative