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Updated: Jun 7, 2026
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Validation of Therapeutic Agent Conjugation to Polyvinyl Alcohol-Coated Medical Devices
Published on: November 29, 2024
Sustained release of proteins from a modified vaginal ring device
Ryan J Morrow1, A David Woolfson, Louise Donnelly
1School of Pharmacy, Queen's University Belfast, Belfast, Northern Ireland, UK.
Summary
A novel vaginal ring technology, the insert vaginal ring (InVR), enables effective delivery of large molecules like proteins and antibodies. This innovation offers potential for long-term drug release and HIV prevention for women.
Area of Science:
- Biomaterials Science
- Drug Delivery Systems
- Reproductive Health Technologies
Background:
- Conventional vaginal rings (VRs) struggle to deliver hydrophilic and macromolecular drugs due to material limitations.
- Hydrophobic elastomers used in traditional VRs hinder the permeation of peptides, proteins, and antibodies.
- Existing VRs are largely ineffectual for complex therapeutic agents.
Purpose of the Study:
- To introduce a new vaginal ring technology, the insert vaginal ring (InVR).
- To demonstrate the InVR's capability in delivering hydrophilic and macromolecular actives.
- To showcase the potential of InVR for sustained drug release and disease prevention.
Main Methods:
- Development of the insert vaginal ring (InVR) technology.
- Incorporation of model protein Bovine Serum Albumin (BSA) into various insert matrices.
- Fabrication of matrices including modified silicone rods, directly compressed tablets, and lyophilised gels.
- Testing the release profiles of actives from InVR devices over time.
- Quantification of monoclonal antibody 2F5 delivery from a single InVR device.
Main Results:
- Demonstrated controlled release of Bovine Serum Albumin (BSA) from multiple InVR insert matrices.
- Achieved sustained release profiles ranging from several hours to over 4 weeks.
- Successfully delivered over 1 mg of the monoclonal antibody 2F5 from a single InVR device.
- Validated the InVR's efficacy for delivering both proteins and antibodies.
Conclusions:
- The insert vaginal ring (InVR) technology effectively overcomes limitations of conventional vaginal rings for macromolecular drug delivery.
- InVR enables tunable, controlled release of therapeutics over extended periods.
- InVR presents a promising platform for long-acting drug delivery, including potential for HIV prevention in women.
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