These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Preclinical studies on thiocarboxanilide UC-781 as a virucidal agent. Author: Balzarini J, Naesens L, Verbeken E, Laga M, Van Damme L, Parniak M, Van Mellaert L, Anné J, De Clercq E. Journal: AIDS; 1998 Jul 09; 12(10):1129-38. PubMed ID: 9677161. Abstract: BACKGROUND: Thiocarboxanilide UC-781 is a highly potent and selective non-nucleoside reverse transcriptase inhibitor (NNRTI) of HIV-1, which also has virucidal properties. Recent studies have shown that UC-781 would seem an ideal candidate for application as a vaginal virucide. OBJECTIVE: To investigate the antiviral potency and stability of UC-781 in a lipophilic gel formulation. METHODS: UC-781 was formulated in replens gel at different concentrations and administered intravaginally to rabbits at 5% in replens gel for 10 days. UC-781 was also exposed to temperatures of 4, 37 and 50 degrees C, and to low pH (6.0, 4.3, 2.0 and 1.2). A number of microorganisms were exposed in culture to serial dilutions of UC-781. RESULTS: The drug was stable under low pH conditions and did not lose its antiviral potency upon 4 h exposure to pH 3.5 (the estimated vaginal pH). UC-781 can be easily formulated into a lipophilic gel (replens; up to 5%) and proved fully stable at 50 degrees C for 30 days. There was no effect on the growth of microorganisms (i.e., Candida and Lactobacillus strains) that are present in the vaginal flora. Neither systemic side-effects, nor local inflammation or damage of the vaginal mucosa or epithelium were observed in rabbits to which 5% UC-781 in replens gel had been administered. UC-781, formulated as 0.5, 0.2 and 0.05% replens gel, and UC-38, alpha-APA and zidovudine, formulated as 0.5 or 0.2% replens gel, were effective in protecting CEM cells in the very beginning against productive HIV-1 replication. This points to an efficient diffusion of the drugs from the lipophilic gel to the hydrophilic culture medium. However, subsequent subcultivations at a dilution rate of 1:10 every 3-4 days resulted in a rapid breakthrough of virus with all drugs except UC-781 in its 0.5 and 0.2% gel formulation. These cultures were fully protected against HIV-1 and remained completely cleared from virus for at least 10 subcultivations. CONCLUSIONS: The virus that emerged under 0.05% UC-781 remained highly sensitive to the NNRTI, including UC-781, in cell culture, suggesting a lack of resistance development under our experimental conditions.[Abstract] [Full Text] [Related] [New Search]