Cibinqo: what flexibility did regulators accept, and why?

“Indeed, the pharmacological relevance of the monkey was therefore questionable, as no cross-reactivity studies with abrocitinib had been presented.”

“Overall, given the historical context and the possibility to build on previous experience and data from other JAK inhibitors, the use of monkey in the development programme was considered sufficiently justified by CHMP.”

“Abrocitinib was positive in an in vitro micronucleus assay and determined to be an aneugen in a follow-up study; however, it was not genotoxic in an in vivo micronucleus assay in rats.”

“Collectively, the genotoxicity studies presented do not indicate a genotoxic risk for abrocitinib at the proposed clinical dose of 200 mg QD.”

“However, thymomas were evident in females already from the lowest dose, with low margins of exposure to human exposure.”

“Nevertheless, given the unclear human relevance of the thymoma findings, the applicant included data in section 5.3 of the SmPC.”