FDA Rejects Regulatory Filing For Zogenix Epilepsy Drug; GW Pharma Moves In Sympathy

Zogenix, Inc.,which develops therapies for rare diseases, said Monday afternoon the FDA issued a refusal to file letter regarding its NDA for Fintepla, chemically fenfluramine hydrochloride, which is being evaluated for the treatment of seizures associated with Dravet syndrome. The FDA determined the NDA wasn't sufficiently complete to permit a substantive review, primarily due to two reasons: non-submission of certain non-clinical studies for assessing chronic administration of the pipeline asset and an incorrect version of a clinical dataset, which prevented the completion of the review process required to support the filing. Fintepla, previously codenamed ZX008, is Zogenix's lead asset and was touted to be a multi-billion-dollar opportunity for the company. The adverse development suggests a serious setback to the small-cap biotech. Bank of America analyst Tazeen Ahmad said last September ZX008's worldwide, risk-adjusted peak sales is estimated to be $1.5 billion in 2029, comprising a $604-million opportunity in Dravet syndrome, $503 million in Lennox-Gastaut syndrome and $386 million in other pediatric epilepsy conditions.