SpeciesAcceptedBeyond the letter
All toxicology conducted with homologous surrogate antibodies (REGN646 in cynomolgus monkey, REGN1103 in mouse), not with dupilumab
Why: Dupilumab does not cross-react with IL-4Rα from nonclinical species · No relevant species
“Because dupilumab does not cross-react with species used to evaluate nonclinical safety, the toxicology studies were conducted with homologous anti-IL-4Rα monoclonal antibodies REGN646 and REGN1103 in cynomolgus monkeys and CD-1 mice, respectively, to identify potential hazards associated with inhibition of IL-4 and IL-13.”
✓ VerifiedFDA pharmacology/toxicology review, p. 17Source ↗ “Given the lack of cross-reactivity of dupilumab with IL-4Rα from non-clinical species, surrogate mAbs were used, which is acceptable.”
✓ VerifiedEMA assessment report, p. 22Source ↗ CarcinogenicityAccepted
No carcinogenicity studies for a chronic non-oncology indication; weight-of-evidence assessment from IL-4/IL-13 literature and surrogate toxicity data
Why: Weight-of-evidence approach in accordance with ICH S6(R1); IL-4/IL-13 pathway literature · Weight of evidence · Within the guideline · Pharmacology or kinetics
“No carcinogenicity studies were conducted. However, an assessment of the carcinogenic potential of dupilumab was made based on literature data on the role of the IL-4/IL-13 pathway in tumour development and on non-clinical data for both REGN646 and REGN1103.”
✓ VerifiedEMA assessment report, p. 20Source ↗ “The applied weight of evidence approach is in accordance with ICH S6(R1). It can be agreed that chronic treatment with dupilumab is not associated with an increased risk of cancer.”
✓ VerifiedEMA assessment report, p. 20Source ↗ Safety marginAcceptedBeyond the letter
No meaningful exposure multiples to human dupilumab exposure because toxicity studies used a surrogate antibody
Why: Chronic study Ctrough was 52x the in vitro IC90, showing sufficiently high exposure · Pharmacology or kinetics
“Given that the toxicity studies were conducted with a surrogate antibody a direct comparison of exposure multiples in the toxicity studies with exposure of dupilumab in humans is not considered meaningful.”
✓ VerifiedEMA assessment report, p. 22Source ↗ “However, the Ctrough at the end of treatment in the chronic toxicity study corresponds to 52x of IC90 determined for REGN646-mediated inhibition of IL-4-stimulated TARC section in vitro. This indicates that a sufficiently high exposure to REGN646 was maintained throughout the study.”
✓ VerifiedEMA assessment report, p. 22Source ↗