Properties of a new acid-buffering bioadhesive vaginal formulation (ACIDFORM)

Area of Science:

• Reproductive Health
• Biomaterials Science
• Infectious Disease Prevention

Background:

• Vaginal prophylactic methods are crucial for preventing HIV, STDs, and unplanned pregnancies.
• Existing delivery systems have limitations in maintaining efficacy and retention.
• A novel delivery system, ACIDFORM, was developed to enhance vaginal protection.

Purpose of the Study:

• To evaluate the in vitro properties of ACIDFORM, including acid-buffering, bioadhesion, viscosity retention, and spermicidal activity.
• To compare ACIDFORM's performance against marketed vaginal formulations.
• To assess the long-term stability of ACIDFORM.

Main Methods:

• In vitro testing of ACIDFORM's acid-buffering capacity using NaOH titration and semen mixing.
• Assessment of bioadhesion using excised sheep vagina and cellophane models.
• Evaluation of viscosity retention upon dilution.
• In vitro spermicidal activity testing.
• Long-term stability assessment.

Main Results:

• ACIDFORM exhibits significantly higher acid-buffering capacity compared to Aci-Jel.
• ACIDFORM demonstrates superior bioadhesion to vaginal and cellophane membranes versus multiple commercial products.
• ACIDFORM retains viscosity better than marketed products upon dilution.
• ACIDFORM possesses spermicidal properties and is stable for at least two years.

Conclusions:

• ACIDFORM presents enhanced physicochemical properties compared to existing vaginal delivery systems.
• The gel's characteristics suggest potential utility as a standalone antimicrobial contraceptive.
• ACIDFORM could serve as a versatile formulation vehicle for other active pharmaceutical ingredients.