Ensysce Biosciences Secures IRB Approval for Final Phase of Clinical Study

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

Apr. 16, 2026 at 12:06pm

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A ghostly, translucent X-ray photograph showing the internal structure of an opioid pill capsule, conceptually representing the advanced technology within the PF614-MPAR overdose-protection medication.An advanced opioid medication designed with innovative overdose-protection technology aims to improve safety and save lives.San Diego Today

Ensysce Biosciences, a clinical-stage pharmaceutical company, announced that it has received Investigational Review Board (IRB) approval to initiate Part 3 of the PF614-MPAR-102 clinical study, marking the final stage in evaluating its novel MPAR® (Multi-Pill Abuse Resistance) overdose-protection technology. PF614-MPAR, which received Breakthrough Therapy designation from the FDA, is designed to provide active protection against oral overdose, addressing a critical unresolved risk in opioid therapy.

Why it matters

Nearly 80,000 lives are lost annually to opioid overdose in the U.S., with prescription opioids contributing meaningfully to this ongoing crisis. Ensysce's MPAR® technology introduces a new class of chemically engineered opioids designed to actively protect patients, even in cases of dosing errors or misuse, which is a critical step toward establishing a new standard for opioid safety.

The details

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.

  • Ensysce Biosciences received IRB approval to initiate Part 3 of the PF614-MPAR-102 clinical study on April 16, 2026.

The players

Ensysce Biosciences, Inc.

A clinical-stage pharmaceutical company pioneering next-generation pain and central nervous system therapeutics engineered to minimize abuse and overdose risk.

PF614-MPAR

Ensysce's novel MPAR® (Multi-Pill Abuse Resistance) overdose-protection technology that received Breakthrough Therapy designation from the FDA.

Lynn Kirkpatrick, Ph.D.

Chief Executive Officer of Ensysce Biosciences.

National Institute on Drug Abuse (NIDA)

The organization providing ongoing support for the PF614-MPAR-102 study.

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What they’re saying

“Nearly 80,000 lives are lost annually to opioid overdose in the U.S., with prescription opioids contributing meaningfully to this ongoing crisis. 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.”

— Lynn Kirkpatrick, Chief Executive Officer of Ensysce Biosciences

What’s next

Part 3 of the PF614-MPAR-102 study is designed to further characterize the protective effect of PF614-MPAR across a range of dosing scenarios.

The takeaway

Ensysce Biosciences' PF614-MPAR technology represents a significant advancement in opioid safety, as it is designed to actively protect patients from overdose, even in cases of misuse or dosing errors. This innovation could help address the ongoing opioid crisis and establish a new standard for safer opioid treatments.