Rectal Douche as HIV Pre-Exposure Prophylaxis for Receptive Anal Intercourse: An End User Tenofovir Powder Sachet...

Area of Science:

• HIV Prevention Research
• Pharmacology and Drug Delivery
• Sexual Health Interventions

Background:

• Unprotected receptive anal intercourse (RAI) presents the highest risk for sexual HIV transmission.
• Development of on-demand, topical pre-exposure prophylaxis (PrEP) is crucial for diverse user preferences.
• This study evaluates user preparation of tenofovir douches from different powder formulations.

Purpose of the Study:

• To assess end-user proficiency in preparing topical tenofovir douches.
• To compare user experience with lyophilized versus spray-dried tenofovir powder formulations.
• To evaluate the feasibility and potential for future use of on-demand topical PrEP.

Main Methods:

• Cisgender adult men with RAI history were randomized to prepare tenofovir douches from lyophilized or spray-dried powders.
• Participants prepared multiple douche bottles, with aliquots analyzed for tenofovir concentration, osmolality, and pH.
• User experience, preparation ease, and likelihood of future use were assessed via questionnaire.

Main Results:

• Most participants found both formulations easy to prepare and expressed likelihood of future use.
• The lyophilized product was preferred by participants.
• Lyophilized douches met osmolality and tenofovir specifications more consistently (89% and 81%) than spray-dried (61% and 29%).
• Challenges included sachet opening and transferring spray-dried powder.

Conclusions:

• Topical tenofovir douches are perceived as easy to prepare, with high likelihood for future use.
• Lyophilized formulations demonstrated better adherence to preparation specifications.
• Product modifications are needed for spray-dried formulations to improve consistency and user experience.