FDA's First Step In Xenazine Review: Work Around Clinical Evidence Guidance
This article was originally published in Pharmaceutical Approvals Monthly
Shepherding the orphan Huntington’s chorea drug Xenazine through a three-year review, top-level FDA reviewers invoked the concept of "confirmatory evidence" to circumvent the agency’s preference for two randomized clinical trials to support new drug approval.
You may also be interested in...
Biogen and Eisai's surprise decision to advance Alzheimer’s antibody despite mixed clinical results could follow a similar path as pioneering neurodegenerative therapies Xenazine and Rilutek, or more recent Parkinson’s drug Nourianz – or could end with suspended development, like Kyndrisa.
Meaning of 'confirmatory evidence' becomes review issue in some of US FDA's most difficult choices: when a drug for a significant unmet medical need is supported by a single inadequate – but not failed – clinical trial. Neurology division director Dunn and review team leader Marler explain their interpretations in Ocrevus review memos.
Unmet need is high in Huntington’s disease and the protracted review of Xenazine – the only drug cleared for the disease by FDA – suggests regulatory precedent for approval based on just one efficacy endpoint and with lots of development and safety baggage.