# Development and pre-clinical evaluation of a novel Polymer-Based In-Situ Forming Implant (ISFI) for Long-Acting HIV PrEP

> **NIH NIH R01** · UNIV OF NORTH CAROLINA CHAPEL HILL · 2020 · $551,656

## Abstract

Abstract
Oral pre-exposure prophylaxis (PrEP) with TDF/FTC is an effective prevention intervention for HIV
acquisition, in particular when adherence is high [1-4]. However, poor adherence renders this therapy
ineffective [5]. Innovations recently introduced into the field of systemic PrEP are long-acting (LA) formulations
of antiretrovirals (ARVs) that stably release drugs over many weeks as nano-formulations [6] and have activity
in animal models of prevention [7]. To date no systemic LA drug formulations have demonstrated HIV
prevention in humans though phase II safety studies of LA Cabotegravir are underway. Injection of these LA
ARV are preceded by approximately one month of therapy with the oral formulations to assess for allergy or
serious toxicity as once injected these agents have detectable levels for months and the drug cannot be
removed or have clearance accelerated. The ultimate goal of this proposal is to address these limitations and
develop an injectable polymer-based delivery system for LA PrEP that offers durable and sustained protection
from HIV transmission, high efficacy of HIV inhibition, increased user compliance, and the ability to be removed
in case of unanticipated adverse events or when considering discontinuation from the LA PrEP. We will achieve
this goal by developing a liquid ARV formulation utilizing excipients that form a biodegradable depot after
subcutaneous injection (in-situ forming implant (ISFI)). We propose a comprehensive evaluation of this novel
drug delivery approach using 1) highly relevant transmitted/founder viruses and highly relevant modes of HIV
acquisition via physiologically relevant cell-free and cell-associated viruses, in the presence of human semen
using BLT humanized mice; and 2) a highly relevant macaque model of mucosal simian/human
immunodeficiency virus (SHIV) as an invaluable preclinical tool to assess the efficacy of the ISFI against SHIV
acquisition. This cutting edge combined approach will be utilized to evaluate the scientific premise of our
proposal to investigate whether sustained protection against HIV acquisition can be achieved using a unique
and highly innovative long-acting coitally-independent antiretroviral ISFI formulation.

## Key facts

- **NIH application ID:** 10073463
- **Project number:** 5R01AI131430-04
- **Recipient organization:** UNIV OF NORTH CAROLINA CHAPEL HILL
- **Principal Investigator:** Soumya Rahima Benhabbour
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $551,656
- **Award type:** 5
- **Project period:** 2017-03-06 → 2022-02-28

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10073463

## Citation

> US National Institutes of Health, RePORTER application 10073463, Development and pre-clinical evaluation of a novel Polymer-Based In-Situ Forming Implant (ISFI) for Long-Acting HIV PrEP (5R01AI131430-04). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/10073463. Licensed CC0.

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