Safety pharmacologyAcceptedBeyond the letter
Respiratory, renal, CNS safety pharmacology and TDAR studies done only in rats, a pharmacologically non-relevant species
Why: Standard clinical observations in the chronic monkey study sufficient · Other reason
“The T cell dependent antibody response (TDAR) assay, respiratory, renal, and CNS safety pharmacology studies were conducted in rats, a pharmacologically non-relevant species for CCX168.”
✓ VerifiedFDA multi-discipline review, p. 468Source ↗ “The Division agreed that these studies are not required and that standard clinical observations in the chronic monkey study would be sufficient to fulfill the safety pharmacology study requirements.”
✓ VerifiedFDA multi-discipline review, p. 468Source ↗ OtherCriticised but acceptedBeyond the letter
No dose-limiting effects or target organs in chronic studies; maximum feasible doses with only about 4- to 15-fold AUC margins
Why: Maximum feasible doses given dose volume, formulation concentration and tolerability constraints · Pharmacology or kinetics
“No dose-limiting effects or target organ of toxicity were noted in the chronic studies and therefore, the toxicology of avacopan is not considered fully explored. However, the maximum dose levels employed were the maximum feasible dose levels based on dose volume and formulation concentration constraints, and/or formulation tolerability.”
✓ VerifiedEMA assessment report, p. 21Source ↗ “The AUC exposure margins relative to the human AUC exposure are approximately 4, 15 and 4 in hamsters, rats and monkeys, respectively.”
✓ VerifiedEMA assessment report, p. 27Source ↗ SpeciesAcceptedBeyond the letter
Hamster used as the main rodent species for general, reproductive and carcinogenicity studies
Why: Justified by pharmacology and pharmacokinetic data · Pharmacology or kinetics
“The selection of the main toxicology species, hamster and Cynomolgus monkeys is justified based on pharmacology and pharmacokinetic data.”
✓ VerifiedEMA assessment report, p. 27Source ↗