Zogenix has announced it will resubmit a New Drug Application (NDA) for Fintepla (ZX008), its investigational anti-seizure therapy for patients with Dravet syndrome, likely in the third quarter of this year.
The U.S. Food and Drug Administration (FDA) refused the first NDA for Fintepla in April. In a Refusal to File (RTF) letter, the FDA cited Zogenix’s failure to include non-clinical studies addressing the chronic administration of fenfluramine hydrochloride, Fintepla’s active substance. The agency also said one of the clinical datasets included in the application was incorrect, preventing the completion of the review process required for NDA filing.
Zogenix and FDA reviewed the two issues identified in the RTF letter in a Type A meeting held in May.
Based on that meeting, the FDA agreed that Zogenix can resubmit its application without the need to include new chronic toxicity studies, which had been requested in the RTF letter.
The pharmaceutical company also conducted and discussed with the FDA a root cause analysis to explain the incorrect clinical data included in the first NDA. The FDA agreed that Zogenix may resubmit the datasets in the new NDA.
“We are very pleased with the outcome of our meeting with the FDA and appreciate their thoughtful approach in considering the totality of the data from our drug development program, along with additional clinical and non-clinical literature that will be referenced in our resubmission,” Stephen J. Farr, PhD, president and CEO of Zogenix, said in a press release.
“We now have the clarity required to successfully resubmit our Fintepla NDA, which we anticipate will occur in the third quarter,” he added.
In the meantime, the FDA has rescinded Breakthrough Therapy designation for Fintepla for the treatment of seizures associated with Dravet syndrome. Fintepla no longer fills the criteria for this designation, since two therapies — Diacomit (stiripentol), developed by Laboratoires Biocodex, and GW Pharmaceuticals‘ Epidiolex, a plant-derived cannabidiol (CBD) — have been approved for Dravet syndrome.
However, this rescission is not expected to limit the potential for Priority Review status for Zogenix’s resubmitted NDA.
Breakthrough therapy designation is intended to accelerate the development and review of a potential therapy for a serious or life-threatening disease, with clinical evidence of substantial improvement over existing options. Priority Review means the FDA can take action on an application within 6 months, instead of a standard review of 10 months.
Fintepla is a low-dose oral solution of fenfluramine hydrochloride. The therapy is given with other treatments to reduce the frequency of epileptic seizures. Fintepla is currently being tested in three Phase 3 clinical studies — ZX008-1501 (NCT02682927), ZX008-1502 (NCT02826863), and the open-label extension study (NCT02823145). The ZX008-1502 trial is currently recruiting participants; more information can be found on the trial’s page.