# 1-Year Sustained Release Naltrexone Implant for the prevention of relapse to opioid dependence

> **NIH NIH UG3** · DELPOR, INC. · 2020 · $3,184,237

## Abstract

The human and economic toll of the opioid epidemic is staggering. Opioid Use Disorder (OUD) is recognized
as a chronic condition and Medication Assisted Treatment (MAT) is now considered first-line and an essential
component of long-term treatment. FDA-approved drugs to treat OUD, including naltrexone, are effective and
save lives. Long-term retention on medications is associated with improved outcomes. These are some of the
conclusions of a recent National Academy of Sciences consensus report. In 2017 over 11 million people
misused opioids, and over 2 million people reported having OUD. Drug overdose is the leading cause of
accidental death in the US, and opioid overdose deaths drove down the US life expectancy over the last 3
years. The annual cost of the opioid crisis was estimated at $115 billion in 2017. MAT is one of the major
pillars of the federal response to the opioid epidemic in the US. Naltrexone is one of the 3 medications
commonly used to treat OUD, available as a once daily pill, or as a once-monthly injectable. Existing
formulations have a short duration and a poor PK profile, resulting in poor medication adherence, with retention
as low as 10% after 4 months. The lack of longer acting prophylactic pharmacologic options for OUD patients
during maintenance therapy is an unmet medical need. Delpor is in a unique position to contribute, and quickly.
The proposed product is a titanium implant loaded with a formulation of naltrexone and a naturally occurring
carboxylic acid. The device is implanted subcutaneously in the abdomen via a custom implanter tool, with local
anesthetic during a simple 10-minute in-office procedure. The technology is based on a unique formulation that
keeps the pH within the reservoir low, and in doing so, promotes passive diffusion of naltrexone. The benefits
of the product include: a) complete medication adherence for 1 year after one administration b) fewer relapses
c) smooth PK profile ensuring complete prophylaxis without sub-therapeutic plasma troughs, d) full reversibility
in case pain treatment is needed (accident, surgery), and e) same efficacy with less drug exposure.
The technology has been validated clinically with another drug (risperidone), and tested preclinically with
naltrexone. A preferred naltrexone formulation has been selected; preliminary animal data indicate zero order
drug release without decline, and we predict that a 1-year system is achievable in human subjects with 2-3
devices. The UG3 phase of this application includes finalizing the Chemistry Manufacturing and Controls,
producing IND supplies, conducting an IND enabling safety study, and submitting the IND. The UG3 transition
milestone is the acceptance of the IND. The UH3 phase will complete the development program required for
an NDA submission. The program will follow the 505(b)(2) regulatory path offering expedited review, and utilize
studies already completed for Delpor’s lead program. The development plan has low technical ri...

## Key facts

- **NIH application ID:** 10023928
- **Project number:** 5UG3DA050306-02
- **Recipient organization:** DELPOR, INC.
- **Principal Investigator:** FRANCIS JOSEPH MARTIN
- **Activity code:** UG3 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $3,184,237
- **Award type:** 5
- **Project period:** 2019-09-30 → 2024-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10023928

## Citation

> US National Institutes of Health, RePORTER application 10023928, 1-Year Sustained Release Naltrexone Implant for the prevention of relapse to opioid dependence (5UG3DA050306-02). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10023928. Licensed CC0.

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