Zogenix has enrolled the last patient in a Phase 3 clinical trial evaluating its lead investigational candidate Fintepla (ZX008) as an add-on therapy for seizures associated with Lennox‑Gastaut syndrome (LGS), the company has announced.
The study’s top-line data are expected in the first quarter of next year.
Fintepla, a low-dose oral solution of fenfluramine hydrochloride, is being developed as a potential add-on treatment for seizures in patients with LGS and Dravet syndrome, another type of severe childhood epilepsy.
In 2017, Fintepla was granted orphan drug designation by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of LGS.
These designations are meant to provide regulatory support and financial benefits, accelerate the clinical development and review of Fintepla, and ensure marketing exclusivity for a specific period upon regulatory approval.
Results from a previous Phase 2 study (NCT02655198) involving 13 young patients with LGS showed that Fintepla was generally well-tolerated and induced a clinically meaningful reduction in the number of seizures in most patients.
In nine patients who received Fintepla for 15 months, their seizure frequency was reduced by a median of 58%, with 67% of the patients achieving at least a 50% reduction and 33% achieving at least a 75% reduction in seizure frequency.
“Based on the compelling data generated in the previously completed Phase 2 study, we believe this promising drug candidate has the potential to become an important new treatment option for the control of seizures in patients suffering from LGS,” Gail M. Farfel, PhD, Zogenix’s executive vice president and chief development officer, said in a press release.
The ongoing Phase 3 clinical trial (NCT03355209) is designed to evaluate the safety and effectiveness of two doses of Fintepla (0.2 or 0.8 mg/kg per day) in reducing seizures in LGS patients, compared with a placebo.
The placebo-controlled, randomized study has completed the recruitment of 263 children and adults with LGS in up to 85 sites in North America, Europe, Asia-Pacific, South America, South Africa, and Australia.
The participants’ seizure frequency has already been determined over four weeks, and they have been randomly assigned to receive one of the two doses of Fintepla (to a maximum of 30 mg a day) or a placebo for a two-week period of dose titration. After this period, patients will receive maintenance treatment at a fixed dose for 12 weeks.
The trial’s primary goal is to assess changes in the frequency of drop seizures between the beginning of the study and after 14 weeks of Fintepla treatment at the 0.8mg/kg daily dose, compared with a placebo.
Secondary goals include a similar assessment for the 0.2mg/kg daily dose of Fintepla, and the determination of the proportion of patients showing a 50% decrease in drop seizures.
Patients completing maintenance treatment may enter the second part of the trial, which consists of a one-year open-label extension study to assess the long-term safety, tolerability, and effectiveness of Fintepla.
“We have been extremely pleased with the rate of enrollment in this trial and look forward to the availability of top-line safety and efficacy data in the first quarter of 2020,” Farfel added.
After the completion of the trial’s second part, participants considered to be candidates for continued treatment with Fintepla may enter an open-label Phase 3 study (NCT03936777) evaluating the long-term safety and effectiveness of ZX008 treatment for up to three years.
Fintepla is also being evaluated as a potential add-on therapy to reduce seizures in patients with Dravet syndrome in Phase 3 clinical studies (NCT02682927, NCT02826863, and NCT02823145).
The investigational therapy is currently being reviewed by the EMA as a treatment for Dravet syndrome, and a New Drug Application was recently resubmitted to the FDA.