H. Lundbeck A/S (Lundbeck) announced positive results from the 12-month open-label extension of the Phase 1b/2a PACIFIC trial, evaluating bexicaserin in participants aged 12-65 with Developmental and Epileptic Encephalopathies (DEEs).

As announced in December 2024, Longboard Pharmaceuticals was acquired by Lundbeck. Longboard developed bexicaserin and conducted the Phase II program, the PACIFIC trial.

"We are very pleased to observe a longer-term sustainable response, along with a favorable safety and tolerability profile over a 12-month period. These results further reinforce our confidence in bexicaserin's unique and potentially best-in-class profile. Considering the significant unmet needs of patients with DEEs, we are encouraged by the long-term sustainability of bexicaserin treatment," said Johan Luthman, EVP and Head of Research & Development at Lundbeck.
 

PACIFIC open-label extension study results:
The PACIFIC OLE study is a 52-week Phase 2, open-label, long-term safety study of bexicaserin in participants with a range of DEEs including Dravet syndrome (n=3), Lennox-Gastaut syndrome (n=20) and DEE Other (n=18), who completed the PACIFIC trial (n=41). The PACIFIC OLE study objectives are to investigate the safety and tolerability of multiple doses of bexicaserin in participants with DEEs, and to analyze the effect of bexicaserin on the frequency of observed countable motor seizures and other seizure types. The analysis of the OLE was conducted when participants reached the approximate 12-month point in the OLE study. The full results are expected to be presented at an upcoming medical conference in 2025.
 

Summary of OLE efficacy results:
The median change in countable motor seizure frequency for participants in the OLE study over an approximate 12-month treatment period was a decrease of 59.3% (n=40) from their baseline entering the PACIFIC OLE study.

The median change in countable motor seizure frequency from baseline for:

• participants randomized to the bexicaserin-treated group in the PACIFIC trial that continued into the 12 month OLE was a decrease of 60.4% (n=31)
• participants randomized to the placebo group in the PACIFIC trial that transitioned to bexicaserin in the OLE was a decrease of 58.2% (n=9) at 12 months.
   

Summary of safety and tolerability results
100% of PACIFIC trial completers elected to enroll in the OLE with 92.7% (38 out of 41) remaining throughout the 12-month open-label period.

Favorable safety and tolerability results were observed in this study. The most common treatment emergent AEs in the overall group (n=41) occurring in >5% of patients for the full 12-month OLE study were upper respiratory tract infections, seizures, COVID-19, decreased appetite, lethargy, pyrexia, gait disturbance, gastroenteritis viral, pneumonia, sinusitis, vomiting, weight decreased and rash.  One participant discontinued due to the adverse event (AE) of lethargy, one participant discontinued by withdrawal of consent and one participant discontinued due to other (relocation).
 

About the PACIFIC trial
The PACIFIC trial is a Phase 1b/2a double-blind, placebo-controlled clinical trial to assess the safety, tolerability, efficacy, and pharmacokinetics of bexicaserin (LP352) in 52 participants between the ages of 12 and 65 years old with DEEs at 34 sites across the United States and Australia. Following a 5-week screening period and baseline evaluations, study participants initiated a dose titration over a 15-day period and subsequently continued on the highest tolerated dose throughout the maintenance period of 60 days. Following the maintenance period, participants were then titrated down, and eligible participants were given the opportunity to enroll in a 52-week open-label extension study.
 

About Bexicaserin
Bexicaserin (LP352) is an oral, centrally acting 5-hydroxytryptamine 2C (5-HT2C) receptor superagonist with no observed impact on 5-HT2B and 5-HT2A receptor subtypes. It is being evaluated in a global Phase III clinical program (the DEEp Program). The FDA has granted Breakthrough Therapy Designation for bexicaserin for the treatment of seizures associated with Developmental and Epileptic Encephalopathies (DEEs) for patients two years of age and older. Bexicaserin is an investigational compound that is not approved for marketing by the FDA or any other regulatory authority.
 

Contacts

About H. Lundbeck A/S
Lundbeck is a biopharmaceutical company focusing exclusively on brain health. With more than 70 years of experience in neuroscience, we are committed to improving the lives of people with neurological and psychiatric diseases.

Brain disorders affect a large part of the world's population, and the effects are felt throughout society. With the rapidly improving understanding of the biology of the brain, we hold ourselves accountable for advancing brain health by curiously exploring new opportunities for treatments.

As a focused innovator, we strive for our research and development programs to tackle some of the most complex neurological challenges. We develop transformative medicines targeting people for whom there are few or no treatments available, expanding into neuro-specialty and neuro-rare from our strong legacy within psychiatry and neurology.

We are committed to fighting stigma and we act to improve health equity. We strive to create long term value for our shareholders by making a positive contribution to patients, their families and society as a whole.

Lundbeck has approximately 5,500 employees in more than 50 countries and our products are available in more than 80 countries. For additional information, we encourage you to visit our corporate site www.lundbeck.com and connect with us via LinkedIn.