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Oral Combinational Antiretroviral Treatment in HIV-1 Infected Humanized Mice
Published on: October 6, 2022
Subdermal implants for HIV prevention with increased dapivirine release rates.
Siqi Wang1, Rand Z Murtadha1, R Karl Malcolm1
1School of Pharmacy, Medical Biology Centre, Queen's University Belfast, Belfast BT9 7BL, UK.
International Journal of Pharmaceutics
|June 21, 2026
Summary
Researchers developed new dapivirine (DPV) subdermal implants for HIV prevention. Formulations achieved significantly higher DPV release rates compared to earlier versions, advancing long-acting pre-exposure prophylaxis (PrEP) options.
Area of Science:
- Biomedical Engineering
- Pharmacology
- Materials Science
Background:
- Dapivirine (DPV) vaginal rings are used for HIV prevention.
- Longer-acting antiretroviral products for HIV pre-exposure prophylaxis (PrEP) are needed.
- Previous DPV subdermal implants had low drug release rates.
Purpose of the Study:
- To develop next-generation dapivirine (DPV) subdermal implant formulations.
- To increase DPV daily release rates for potential HIV prevention.
- To evaluate different formulation strategies for enhanced drug delivery.
Main Methods:
- Formulation of reservoir-type implants with a Kolliphor® EL core.
- Fabrication of dip-coated reservoir implants with a rate-controlling membrane.
- Development of simple matrix-type silicone elastomer implants.
- In vitro evaluation of DPV release rates.
Main Results:
- Replacing the silicone core with Kolliphor® EL increased DPV solubility and flux by ~1.5-fold.
- Dip-coated implants achieved daily release rates of 19-41 µg/day.
- Matrix-type implants without a membrane delivered up to 185 µg/day.
Conclusions:
- New DPV implant formulations demonstrate significantly improved release rates.
- Formulation strategies influence DPV release from silicone subdermal implants.
- Findings provide a basis for further in vivo evaluation of these long-acting PrEP candidates.
Keywords:
Controlled releaseHIV/AIDSLong-acting formulationsPre-exposure prophylaxisSilicone elastomerZero-order kineticsMore Related Videos
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