DARTAcceptedBeyond the letter
No reproductive and developmental toxicity studies; literature-based assessment of PD-1/PD-L1 blockade risk instead
Why: PD-1/PD-L1 blockade expected to disrupt fetomaternal immune tolerance; literature-based assessment judged acceptable · Weight of evidence · Pharmacology or kinetics
“No reproductive and developmental studies were conducted because of potential adverse effects of the blockade of PD‐1/programmed death‐ligand 1 (PD‐L1) pathway on the immune tolerance at the fetomaternal interface.”
✓ VerifiedFDA multi-discipline review, p. 50Source ↗ “The FDA agrees that dedicated reproductive and developmental toxicity studies are not needed to support this BLA submission, and the Applicant’s literature‐based assessment of the potential reproductive toxicity of dostarlimab is acceptable.”
✓ VerifiedFDA multi-discipline review, p. 51Source ↗ DARTQuestioned
No fertility studies; monkey reproductive organ data from sexually immature animals, so fertility risk unknown
“While fertility studies were not submitted, no notable effects on the male and female reproductive organs were observed in monkeys in the 1 month and 3 month repeat dose toxicology studies; however, these results may not be representative at all of the potential clinical risk because of the immaturity of the reproductive system of animals used in the studies.”
✓ VerifiedEMA assessment report, p. 43Source ↗ “Therefore, fertility toxicity remains unknown (see SmPC section 5.3).”
✓ VerifiedEMA assessment report, p. 43Source ↗ Safety marginAcceptedBeyond the letter
No NOAEL established in the 13-week monkey study (finding in one low-dose 10 mg/kg animal)
Why: Dostarlimab well tolerated; no special hazard identified in monkey studies up to 3 months · Weight of evidence
“However, in the 13-week repeat dose study, the NOAEL could not be established, due to the finding described above occurring in one animal in the low dose group (10 mg/kg).”
✓ VerifiedEMA assessment report, p. 43Source ↗ “Overall, dostarlimab appears to be well tolerated and no special hazard were identified for humans based on repeat-dose toxicity studies of duration up to 3 months in the cynomolgus monkey (see SmPC section 5.3).”
✓ VerifiedEMA assessment report, p. 43Source ↗