Ensysce Biosciences Secures IRB Approval of Final Phase of PF614-MPAR-102 Clinical Study

~ Advances First-in-Class Opioid with Oral Overdose-Protection ~

SAN DIEGO, CA / ACCESS Newswire / April 16, 2026 / Ensysce Biosciences, Inc. (NASDAQ:ENSC) ("Ensysce" or the "Company"), a clinical-stage pharmaceutical company pioneering next-generation pain and central nervous system therapeutics engineered to minimize abuse and overdose risk, today announced Investigational Review Board (IRB) approval to initiate Part 3 of the PF614-MPAR-102 clinical study, marking the final stage in this study evaluating its novel MPAR (Multi-Pill Abuse Resistance) overdose-protection technology.

PF614-MPAR, which received Breakthrough Therapy designation from the U.S. FDA following the PF614-MPAR-101 study, represents a fundamentally new approach to opioid safety. Unlike conventional abuse-deterrent formulations, PF614-MPAR is designed to provide active protection against oral overdose-addressing a critical unresolved risk in opioid therapy. PF614-MPAR uses a proprietary chemical control mechanism that maintains therapeutic opioid exposure under prescribed use, while automatically limiting additional opioid release when excessive doses are ingested. This "built-in safety switch" introduces a new therapeutic paradigm: opioids engineered not only for efficacy, but for controlled exposure under conditions of misuse.

Previously published clinical data demonstrate that PF614-MPAR delivers consistent, therapeutic plasma levels under normal dosing conditions, while significantly attenuating increases in opioid exposure at supratherapeutic doses. Part 3 of the PF614-MPAR-102 study is designed to further characterize this protective effect across a range of dosing scenarios.

Dr. Lynn Kirkpatrick, Chief Executive Officer of Ensysce stated "Nearly 80,000 lives are lost annually to opioid overdose in the U.S., with prescription opioids contributing meaningfully to this ongoing crisis¹. MPAR introduces a new class of chemically engineered opioids designed to actively protect patients, even in cases of dosing errors or misuse. This is a critical step toward establishing a new standard for opioid safety."

The PF614-MPAR-102 study builds on earlier clinical findings and continues formulation development with ongoing support from the National Institute on Drug Abuse (NIDA)².

Beyond pain management, Ensysce is seeking to extend the uses of MPAR across additional therapeutic categories including amphetamines and methadone, with the objective of delivering safer treatments for pain, attention-deficit/hyperactivity disorder (ADHD), and opioid use disorder.