Eisai has ceased its clinical development program for lorcaserin in Dravet syndrome, terminating both the phase 3 MOMENTUM 1 trial (NCT04572243) and the MOMENTUM 2 extended access program. The decision, attributed to recruitment difficulties, impacts patients with this rare epilepsy who had found the drug beneficial. The Dravet Syndrome Foundation (DSF) initially reported the discontinuation in August.
Patients were instructed to discontinue lorcaserin by October to complete final study visits, with no further access to the medication. The DSF is in communication with Eisai to understand the situation and explore potential alternatives, acknowledging the challenges faced by families who relied on lorcaserin as an effective antiseizure treatment when other medications proved inadequate.
The primary obstacle cited by the DSF was the inability to enroll a sufficient number of participants to adequately evaluate lorcaserin's efficacy in Dravet syndrome. The studies commenced in 2020, coinciding with the FDA's approval of fenfluramine (Fintepla; UCB) for Dravet syndrome. The availability of this new treatment option may have diverted potential participants, contributing to the enrollment challenges.
MOMENTUM 1 aimed to enroll 58 patients with Dravet syndrome and evaluate the change in convulsive seizure frequency over a 28-day period as the primary endpoint. Secondary outcomes included the percentage of patients achieving a 50% reduction in convulsive seizures. The study also planned pharmacokinetic analyses to correlate lorcaserin plasma concentrations with efficacy and safety.
Lorcaserin, a selective serotonin 5-HT2c receptor agonist, was previously marketed by Eisai as Belviq, an FDA-approved weight-loss drug. However, in February 2020, Eisai voluntarily withdrew the medication at the request of federal regulators following data from the CAMELLIA-TIMI 61 trial, which indicated an increased risk of cancer in treated patients. Following the withdrawal, Eisai received numerous requests from patients, caregivers, and healthcare professionals for continued access to lorcaserin for Dravet syndrome and other refractory epilepsies, where it was being prescribed off-label.
These requests led to consultations with the FDA, resulting in an agreement to continue MOMENTUM 2, a centralized expanded access program for patients with Dravet syndrome and other refractory epilepsies who were prescribed lorcaserin by their physicians prior to its market withdrawal. This program allowed continued access to the drug based on the individual healthcare provider's assessment of medical appropriateness.
In MOMENTUM 1, patients aged 2 years and older with Dravet syndrome were randomized to receive weight-based doses of lorcaserin oral suspension twice daily for 14 weeks. Eligibility criteria included at least 4 convulsive seizures during a 4-week baseline period, stable antiepileptic drug regimens, and no recent use of lorcaserin (within 4 weeks) or fenfluramine (within 2 months). Patients taking serotonergic drugs or monoamine oxidase inhibitors, or those with other progressive central nervous system diseases, were excluded.
