Longboard Soars on Epilepsy Trial Success, Eyes $150M Share Sale

Longboard Pharmaceuticals recently reported encouraging results from the Phase Ib/IIa PACIFIC study, which evaluated the effects of their drug candidate bexicaserin on patients with developmental and epileptic encephalopathies (DEE). The study demonstrated that bexicaserin, a 5-HT2C receptor superagonist, significantly reduced the occurrence of motor seizures by 53.3% after a 28-day treatment period. This reduction was a primary measure of the study's success.

In comparison to a placebo group, the frequency of seizures was lowered by 20.8%, leading to a placebo-adjusted reduction of 32.5% for bexicaserin. Randall Kaye, the Chief Medical Officer of Longboard, expressed enthusiasm for these preliminary results, suggesting that bexicaserin has the potential to become a leading product in its class and possibly transform the treatment standards for DEE.

Following the announcement of the study's findings, Longboard's stock value experienced a dramatic increase of 316%. The company plans to present more detailed data at future medical conferences and is advancing bexicaserin into Phase III trials.

Bexicaserin is designed for oral administration and acts as a superagonist of the 5-HT2C receptor, which is involved in mood, appetite, and motor behavior regulation through its interaction with the neurotransmitter serotonin. The drug's mechanism of action involves modulating another neurotransmitter, GABA, to decrease the hyperexcitability associated with seizures.

According to Longboard, bexicaserin does not interact with the 5-HT2A or 5-HT2B receptor subtypes, which are commonly linked to adverse effects. In terms of the PACIFIC study's safety profile, the most frequently reported side effects were diarrhea, lethargy, constipation, drowsiness, and a decrease in appetite. Serious adverse events were reported in three participants, but there were no fatalities. However, nine patients in the bexicaserin group withdrew from the study due to treatment-related toxicities, while none of the placebo group experienced serious adverse events or discontinued the study.

The PACIFIC study was structured to assess the safety, tolerability, pharmacokinetics, and efficacy of bexicaserin at dosages of 6-mg, 9-mg, or 12-mg administered three times daily. After an initial screening phase, patients underwent a 15-day titration period to find their highest tolerated dose, which was then maintained for 60 days. Participants were permitted to continue on a stable anti-seizure medication regimen, which could include up to four different medications.

In conjunction with the PACIFIC study results, Longboard initiated a public offering to sell $150 million worth of its voting common stock. The offering is being managed by Cantor and Citigroup as joint lead book-running managers, with Wedbush PacGrow and H.C. Wainwright & Co. serving as lead managers.