# Self-administered microneedle patch for long-acting release of antiretroviral agents

> **NIH NIH R21** · EMORY UNIVERSITY · 2024 · $224,595

## Abstract

ABSTRACT OF PROPOSED RESEARCH
Antiretroviral agents (ARV) have proven successful in preventing new HIV transmission and improving survival
and quality of life in people living with HIV (PLWH). However, there is still no cure, and issues of poor medication
and medical care adherence and limited access to medication are proving challenging and warrant long-term
release formulations. Currently, ARVs available or in development are either long-acting or self-administered,
but not both. Islatravir (EFdA) is a highly potent, sub-nanomolar HIV-1 nucleoside reverse transcriptase
translocation inhibitor that is in Phase 3 development by Merck for the prevention and treatment of HIV-1. A low
dose has recently proven to be safe and effective in PLWH. The high potency of EFdA and the long intracellular
half-life of its active metabolite EFdA 5'-triphosphate (EFdA-TP) make it a strong contender for long-acting
regimens. The overall goal of this study is to develop biodegradable microneedle patches (MNPs) that
encapsulate ARV (such as EFdA) for long-acting release using a self-administered patch. This sustained drug
release can minimize the dosing interval from daily to monthly or longer, which will provide substantial benefits
to PLWH, will address issues of adherence in therapy and prophylaxis, and serve as a good drug administration
route for pediatric patients and persons experiencing homelessness, and be particularly beneficial in certain
parts of the world such as sub-Saharan Africa. The specific aims are: 1) To formulate self-administrable
microneedle patches for EFdA delivery and optimize their extended release in vitro for at least one month;
2) To determine the in vivo pharmacokinetics of EFdA and its intracellular active metabolites after
delivery by a drug-loaded microneedle patch. Towards these goals, we will investigate biodegradable
polymers and casting solvents for the microneedle, and water-soluble materials for the patch backing, to
formulate, fabricate, and characterize EFdA-loaded MNPs. We will test the release of EFdA from MNPs in vitro
and select one or two MNP designs that release EFdA for at least one month to determine the in vivo
pharmacokinetic profile first in rats and then in larger animal such as rabbits. We will compare EFdA release
from MNPs to delivery by subcutaneous injection and oral administration. We anticipate that at least one MNP
design that releases EFdA for at least one month will have a pharmacokinetic profile where the concentration of
EFdA in plasma and of active metabolite EFdA-TP in lymphocytes will be maintained above the target level for
at least one month. We believe PLWH or persons at risk for HIV (including pediatric persons) will greatly benefit
from the potential long-term outcomes of these novel therapeutic and prophylactic patches designed to increase
medication adherence and access.

## Key facts

- **NIH application ID:** 11009194
- **Project number:** 1R21AI186628-01
- **Recipient organization:** EMORY UNIVERSITY
- **Principal Investigator:** MARK R. PRAUSNITZ
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $224,595
- **Award type:** 1
- **Project period:** 2024-07-08 → 2026-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/11009194

## Citation

> US National Institutes of Health, RePORTER application 11009194, Self-administered microneedle patch for long-acting release of antiretroviral agents (1R21AI186628-01). Retrieved via AI Analytics 2026-05-27 from https://api.ai-analytics.org/grant/nih/11009194. Licensed CC0.

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