Next Generation 3D Printed Multipurpose Intravaginal Ring For Sustained Co-Delivery of Antiretroviral Drugs and A...

Globally, a significant overlap exists between females affected by HIV and HSV-2 infections, and who have an unmet need for contraception. Intravaginal rings (IVRs) have become widely accepted by women worldwide for contraception and hormone replacement therapy and provide a promising platform as a multipurpose prevention technology (MPT).

Using state-of-the-art 3D printing process known as continuous liquid interface production (CLIP™), IVRs with an internal honeycomb (HC 2.53 mm) geometry were fabricated with a silicone-urethane resin. IVRs were loaded with a triple-drug combination of an anti-HIV drug (Dapivirine, DPV, 30 mg), an anti-herpes drug (Pritelivir, PTV, 20 mg) and a contraceptive hormone (Levonorgestrel, LNG, 2.0 mg) using a solvent swelling method in acetone.

IVRs elicited zero-order release kinetics following an initial burst for all three APIs when formulated individually or in combination. Release rates were above benchmark therapeutic targets for DPV and LNG (200 µg/day DPV, 20 µg/day LNG). A series of accelerated stability studies demonstrated the physical integrity of IVRs after 6 months of storage at 40ºC/75%RH. DPV remained stable over 6 months, whereas PTV and LNG exhibited significant decrease in concentration after 3 months of storage with presence of degradation products detected by HPLC. Mouse size placebo rings (3 mm OD) elicited 100% cell viability in relevant cell lines and were well tolerated in vivo in mice.

Collectively, these results demonstrate that this first-in-line 3D printed MPT IVR has potential to expand preventative choices for young women and girls against HIV, HSV, and unplanned pregnancy.