~ ~ The Second Study Fully Enrolled for Breakthrough Therapy-Designated, First-in-Class Opioid Designed to Protect Against Oral Overdose ~ ~

SAN DIEGO, CA / ACCESS Newswire / August 31, 2026 / Ensysce Biosciences, Inc. (NASDAQ:ENSC) ("Ensysce" or the "Company"), a biotechnology company developing novel neuroplastogenic therapies beyond mood disorders, with an initial focus on complex pain, and advancing next-generation pain and central nervous system therapeutics designed to reduce abuse and overdose risk, today announced completion of enrollment in the final stage of the PF614-MPAR-102 clinical study. The study evaluated its novel MPAR® (Multi-Pill Abuse Resistance) overdose-protection technology.

Unlike traditional abuse-deterrent technologies, PF614-MPAR is engineered to actively protect against oral overdose, addressing one of the most persistent risks in opioid therapy. Its proprietary chemical-control mechanism provides therapeutic opioid exposure when used as prescribed and automatically limits additional release when excessive doses are taken. This built-in "safety switch" establishes a new therapeutic paradigm: opioids designed not only for efficacy, but also for controlled exposure under misuse conditions.

Part 3 of this second PF614-MPAR study, supported by the National Institute on Drug Abuse (NIDA)1, was designed to further characterize the drug's protective profile against a full range of dosing scenarios. Clinical data published to date demonstrates PF614-MPAR maintains consistent therapeutic plasma levels at normal doses while significantly blunting exposure increases at supratherapeutic levels.