Longboard Pharmaceuticals' Presence at American Epilepsy Society (AES) Annual Meeting Reinforces Ongoing Commitment to the Rare Epilepsy Community

Longboard Pharmaceuticals, Inc. (Nasdaq: LBPH), a clinical-stage biopharmaceutical company focused on developing novel, transformative medicines for neurological diseases, today announced that it will present data for LP352, a novel, highly selective investigational treatment in development for seizures associated with a range of Developmental and Epileptic Encephalopathies (DEEs), in poster sessions at the 2023 AES Annual Meeting. Longboard will also host a scientific exhibit with members of its leadership team to highlight details of the ongoing PACIFIC study, and to discuss LP352 as a potential best-in-class therapy for people living with rare seizure disorders.

"We believe that LP352 has the promise to be a best-in-class therapy for a broad range of DEEs, and we remain committed to moving the space forward. The AES annual meeting gives us the opportunity to collaborate live with the top thought leaders, as we approach PACIFIC topline data in January 2024 and plan for our Phase 3 program for LP352. We look forward to presenting new posters and hosting a scientific exhibit to highlight the differentiating qualities of LP352 and our unique development plan. I am also pleased to continue our work with key advocacy organizations, including participation in the Rare Epilepsy Network's panel: Clustering Rare Epilepsies for Research, Trials & Care," stated Dr. Randall Kaye, Longboard's Chief Medical Officer.

Presentation & Event Details:

Title: Alternate Dosing Regimens for an Immediate Release Formulation of the Novel Antiseizure Medication LP352 Based on Pharmacokinetics (Plasma and CSF) and Pharmacodynamics (QEEG)
Poster number: 3.269
Date/Time: December 4, 2023, from 12:00pm-1:45pm ET
Location: West Hall C, Level 2

Title: LP352 has Negligible CYP or P-glycoprotein Interaction Potential, Minimizing Therapeutic Complexity in Epilepsy Patients With a High Burden of Polypharmacy
Poster number: 3.270
Date/Time: December 4, 2023, from 12:00pm-1:45pm ET
Location: West Hall C, Level 2

Title: LP352, a 5-HT2C Superagonist, Has Broad Antiepileptic Activity in Preclinical Seizure Models
Poster number: 3.261
Date/Time: December 4, 2023, from 12:00pm-1:45pm ET
Location: West Hall C, Level 2

Longboard Scientific Exhibit: A Novel 5-HT2C Superagonist for Treatment of Rare Seizure Disorders: LP352 and the PACIFIC Study
Date/Time: December 4, 2023, from 2:00pm-5:00pm ET
Location: Meeting Room #W315A, Orange County Convention Center, West Concourse, Level 3

About Longboard Pharmaceuticals

Longboard Pharmaceuticals, Inc. is a clinical-stage biopharmaceutical company focused on developing novel, transformative medicines for neurological diseases. Longboard is working to advance a portfolio of centrally acting product candidates designed to be highly selective for specific G protein-coupled receptors (GPCRs). Longboard's small molecule product candidates are based on more than 20 years of GPCR research. Longboard is evaluating LP352, an oral, centrally acting 5-hydroxytryptamine 2C (5-HT2C) receptor superagonist, with no observed impact on 5-HT2B and 5-HT2A receptor subtypes. LP352 is currently in a Phase 1b/2a clinical trial, the PACIFIC Study, evaluating participants ages 12 to 65 years old with a broad range of Developmental and Epileptic Encephalopathies (DEEs), including Lennox-Gastaut syndrome, Dravet syndrome and other DEEs. Enrollment was completed in the summer of 2023, and topline data are expected in January 2024. Longboard is also evaluating LP659, an oral, centrally acting, sphingosine-1-phosphate (S1P) receptor subtypes 1 and 5 modulator, which is in development for the potential treatment of rare neuroinflammatory conditions. Longboard expects to initiate dosing in a Phase 1 single-ascending dose (SAD) clinical trial for LP659 in healthy volunteers later this year.

Forward-Looking Statements

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