Juvenile toxAccepted with a conditionBeyond the letter
Juvenile rat NOAEL gives no safety margin for patients under 12; additional juvenile study (from postnatal day 21) deferred to postmarketing
“The NOAEL was determined to be 0.1 mg/kg/day, which does not provide a margin of safety to support study of pediatric patients <12 years of age. An additional juvenile toxicity study in juvenile rats starting at postnatal day 21 will be required (refer to Postmarketing Requirements and Commitment, Section 14) below.”
✓ VerifiedFDA multi-discipline review, p. 34Source ↗ Impurity or metaboliteVerdict not stated
Major metabolite M1: sponsor proposed exposure-ratio calculations in lieu of a dedicated repeat-dose study; only a rodent study up to 4 weeks conducted
“The Applicant responded that, in lieu of a repeated dose toxicity study, they planned to quantify M1 in plasma samples from phase 2 patients and calculate the ratio of exposure multiples to M1 in the dog to human M1 exposure at the anticipated dose of 50 mg BID.”
✓ VerifiedFDA multi-discipline review, p. 27Source ↗ “In support of the safety of AZ13792925, the Applicant conducted the following studies with the metabolite: single dose toxicity and repeat-dose oral toxicity studies in a rodent up to 4 weeks, genotoxicity (Ames test and in vitro micronucleus assay), 6-month carcinogenicity study in Tg rasH2 mouse, and an embryo-fetal development study in rats.”
✓ VerifiedFDA multi-discipline review, p. 34Source ↗ First doseQuestioned
Proposed first-in-human doses based on the NOAEL of a 7-day rat study
“The Division stated that basing doses for phase 1 clinical studies on the no adverse effect level (NOAEL) from the 7-day rat toxicology study was unacceptable.”
✓ VerifiedFDA multi-discipline review, p. 26Source ↗