# Development of PPL-138, a Novel Mixed NOP/Mu Partial Agonist for Treatment of CocaineUse Disorder

> **NIH NIH U01** · PHOENIX PHARMALABS, INC. · 2022 · $2,680,161

## Abstract

Abstract
Currently, clinically used drug abuse medications exist for treatment of addiction to opiates, alcohol, and nicotine,
but not psychostimulants such as cocaine and methamphetamine (METH). PPL-138 is a non-selective opioid
receptor ligand with partial agonist activity at NOP and mu receptors, and antagonist activity at kappa and delta.
This compound, initially synthesized by Drs. Lawrence Toll and Stephen Husbands in a NIDA funded effort, has
now been licensed by Phoenix PharmaLabs (PPL), where Dr. Toll is a founder. This compound has been
demonstrated to be a potent inhibitor of both cocaine and METH self-administration and reinstatement in rats,
and to be not self-administered in rats or NHPs. Additional pharmacokinetic and safety studies in rodents and
NHPs have demonstrated little to no effect on respiration, constipation, heart rate or blood pressure, up to high
doses, thereby demonstrating a large apparent therapeutic window. It is our hypothesis that the increase in NOP
receptor affinity and activity, compared to buprenorphine, renders PPL-138 less rewarding and better at blocking
drug reward than buprenorphine, a compound demonstrated to reduce craving for psychostimulants. In this
proposed project, PPL will focus on cocaine use disorder (CUD) with an eye on continuing to METH use disorder
(MUD), in the future. To develop PPL-138, PPL has put together an experienced team with expertise in
pharmacology, chemical manufacturing, IND-enabling preclinical studies, regulatory, and first in human studies
and plan to take PPL-138 through each step, culminating in Phase I clinical trials. To accomplish these goals,
experiments have been designed to encompass the following 5 aims. Specific Aim 1 studies performed at Wake
Forest University will conduct final efficacy studies to determine whether PPL-138 is as effective in reducing
cocaine self-administration and relapse in NHPs as it is in rats. Specific Aim 2, will be continue chemical
manufacturing and encompass manufacturing process development and optimization, formulation, and GMP
drug product development and manufacturing. Specific Aim 3 directed by drug discovery and toxicology
consultants and performed primarily at Charles River Laboratories, will include a complete program of IND-
enabling in vitro and in vivo GLP toxicology studies, as well as supporting ADME studies. These will build upon
studies already completed by the previous licensee of this compound and current studies funded by PPL.
Specific Aim 4 will be directed by ICON and devoted to development of regulatory processes and filing an IND.
Finally, Specific Aim 5 will encompass first in human studies, directed by Dr. Frances Levin and run by ICON,
with Single Ascending Dose (SAD) and Multiple Ascending Dose (MAD) studies followed by a Single Dose
Crossover study in human volunteers. With the team of experts developing a very safe compound with a novel
mechanism of action, we expect to determine in humans whether a NOP/mu pa...

## Key facts

- **NIH application ID:** 10616932
- **Project number:** 1U01DA057862-01
- **Recipient organization:** PHOENIX PHARMALABS, INC.
- **Principal Investigator:** Frances Rudnick Levin
- **Activity code:** U01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $2,680,161
- **Award type:** 1
- **Project period:** 2022-09-30 → 2025-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10616932

## Citation

> US National Institutes of Health, RePORTER application 10616932, Development of PPL-138, a Novel Mixed NOP/Mu Partial Agonist for Treatment of CocaineUse Disorder (1U01DA057862-01). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/10616932. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*
