CarcinogenicityAccepted with a conditionBeyond the letter
No carcinogenicity studies before US approval for chronic use in VHL disease; mouse and rat studies required postmarketing
Why: Preliminary weight-of-evidence assessment did not adequately address carcinogenicity for chronic use; studies required postmarketing
“Given the indication, the long-life expectancy and prolonged treatment, it is important to address the carcinogenicity potential of belzutifan for chronic use. Two post-marketing requirements (PMRs) to conduct carcinogenicity studies in mice and rats were communicated to the Applicant.”
✓ VerifiedFDA multi-discipline review, p. 35Source ↗ “During the review cycle, the Applicant submitted a preliminary weight-of-evidence assessment, which did not adequately address the carcinogenicity potential of belzutifan for chronic use.”
✓ VerifiedFDA multi-discipline review, p. 35Source ↗ DARTAccepted
No confirmatory second-species (rabbit) embryo-fetal study; rat pilot study only
Why: ICH S5(R3): teratogenic and embryotoxic potential already shown in the rat study · Within the guideline
“As belzutifan showed teratogenic and embryotoxic potential in the pEFD rat study, a confirmatory study in a second species (rabbit) was not performed and is not required in accordance with ICH S5 (R3).”
✓ VerifiedEMA assessment report, p. 46Source ↗ Safety marginVerdict not stated
Rat seminiferous tubule degeneration at 0.13-fold human AUC (no margin); not seen in dogs at 1-fold
“The seminiferous tubule degeneration was observed at ≥6 mg/kg/day (0.13-fold human AUC) in SD rats but not in dogs with 10 times higher exposure (30 mg/kg/day, 1-fold human AUC).”
✓ VerifiedEMA assessment report, p. 45Source ↗