# Extending duration of an injectable long-acting local anesthetic formulation using novel salts

> **NIH NIH R43** · REBEL MEDICINE INC · 2024 · $295,921

## Abstract

Project Summary
Over 14,000 people die of prescription opioid misuse per year. Opioid-based medications are a mainstay of
postoperative pain management with approximately 80% of surgical patients receiving opioid prescriptions for
postoperative pain management. However, their use is associated with a variety of adverse events such as
addiction, respiratory depression, cognitive impairment, nausea, constipation, and death. Surgery is a critical
point where patients are at risk of developing or worsening opioid-misuse disorders with upwards of 10% of
patients going on to long term use. Additionally, adverse events related to opioids for postoperative pain
management are associated with increased cost of care, hospital length of stay, and readmission rates. A safe
and effective alternative to opioids for postoperative pain management can provide significant value to the
customer, patient, and society alike by reducing opioid-related adverse events and the costs associated with
them. Local anesthetics can temporarily control the pain at a surgical site, but the duration is limited to only a
few hours, after which pain returns and systemic pain medications (e.g. morphine, oxycodone) are required. If
local control of pain at the surgical site can be extended, it could lessen or completely mitigate the need for
systemic opioid medication. The current options for long-acting local anesthesia (e.g. liposomal bupivacaine,
indwelling catheter-based infusion pumps) are plagued with substantial drawbacks such as inadequate efficacy,
high-cost, cumbersome equipment, and risk of complications, which have limited their use and impact. Rebel
Medicine has developed a proprietary oil-based gel to deliver local anesthetics over a period of 3 day, mitigating
the need for prescription opioid use in the acute post-surgical period. While this formulation has shown extended
effect duration in rats, drug loading limitations of the system require larger injection volumes (>3mL) to achieve
effective pain management. Lipophilic salts of local anesthetics may provide not only increased solubility of local
anesthetics in Rebel’s oleogel delivery system, but may provide additional benefits of increased potency and
tunability of drug release from the gel system, allowing for extended pain treatments up to 7 days from a single
dose. Our aim for Phase I is to demonstrate our characterized lipophilic bupivacaine oleogel formulation has
superior in vivo safety and efficacy over with the current clinical standards in a standardized porcine model. We
have an assembled team with demonstrated expertise in medical technology development, drug delivery and
material science, pre-clinical analgesic drug evaluation, pharmacokinetic assessment, and pharmaceutical
commercialization.

## Key facts

- **NIH application ID:** 10922483
- **Project number:** 1R43DA059315-01A1
- **Recipient organization:** REBEL MEDICINE INC
- **Principal Investigator:** Brett Davis
- **Activity code:** R43 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $295,921
- **Award type:** 1
- **Project period:** 2024-09-01 → 2025-08-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10922483

## Citation

> US National Institutes of Health, RePORTER application 10922483, Extending duration of an injectable long-acting local anesthetic formulation using novel salts (1R43DA059315-01A1). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10922483. Licensed CC0.

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