CarcinogenicityAccepted with a conditionBeyond the letter
Lifetime rat and rasH2 mouse studies in pharmacologically inactive species; on-target thyroid C-cell tumor risk not assessable
Why: On-target risk cannot be differentiated from peptide GLP-1 receptor agonists; class boxed warning for thyroid C-cell tumors · Class precedent
“Since orforglipron is not pharmacologically active in wild-type rodents or rasH2 transgenic mice, the absence of thyroid C-cell neoplasia, an on-target effect, was expected.”
✓ VerifiedFDA multi-discipline review, p. 61Source ↗ “The Applicant’s label should therefore carry the boxed warning for thyroid C-cell adenomas/carcinomas and include a statement in Section 5 (WARNINGS AND PRECAUTIONS), consistent with the class.”
✓ VerifiedFDA multi-discipline review, p. 62Source ↗ DARTAccepted with a conditionBeyond the letter
Reproductive toxicity tested only in pharmacologically non-relevant rats and rabbits (off-target assessment)
Why: On-target developmental risk cannot be differentiated from peptide GLP-1 receptor agonists; residual uncertainty addressed in labeling · Class precedent
“Off-target safety was further characterized in several nonpharmacologically relevant species, including rats (general toxicology and reproductive safety assessment), rasH2 transgenic mice (carcinogenicity assessment), and rabbits (reproductive safety assessment).”
✓ VerifiedFDA multi-discipline review, p. 43Source ↗ “While the clinical relevance of reproductive findings and thyroid C-cell tumors for humans is uncertain, we recommend residual uncertainty be addressed in product labeling.”
✓ VerifiedFDA multi-discipline review, p. 44Source ↗ SpeciesVerdict not stated
Rodent general toxicology in rat, an off-target model; monkey the only pharmacologically relevant species
Why: Rat is an off-target model; monkey is pharmacologically relevant
“Wistar rats were selected as the most suitable rodent species; however, rats represent an off-target model of toxicology. Cynomolgus monkeys were selected as the nonrodent species because they are a pharmacologically relevant species.”
✓ VerifiedFDA multi-discipline review, p. 57Source ↗