SAN DIEGO — An easily produced, multiple-reservoir vaginal silicone ring capable of delivering antiviral treatments for HIV and sexually transmitted infection could prevent the transmission of these diseases among women in low-income countries, according to results presented at ICAAC 2015.
“Research on the prevention of HIV infection in young women is a major concern of public health, notably in sub-Saharan Africa,” Meriam Memmi, PhD candidate at University Jean Monnet of Saint-Etienne, France, said during a press event. “Because vaccine is not really an option, we thought to manufacture vaginal rings.”
The preventive reservoirs of the rings are manufactured by mixing silicone with the antiviral agents Viread (tenofovir disoproxil fumarate, Gilead Sciences) or Zovirax (acyclovir, Valeant Pharmaceuticals). These reservoirs, along with the silicone envelope, were baked together and dipped in vaginal fluid, a process that the researchers wrote was low-cost and could be rapidly reproduced. Preliminary analysis of the resulting product using UV spectrophotometry was conducted by the researchers to determine its efficacy, with results influencing further product modification.
After adjustments made to the silicone’s hydrophobicity, analysis suggested that the rings were able to release acyclovir concentrations ranging from 1.5 mg/day to 3.5 mg/day, and tenofovir concentrations ranging from 3 mg/day to 5 mg/day. These concentrations, which persisted for at least 50 days, were capable of preventing infection during preliminary in vitro investigations.
“These results demonstrate the ability of silicone rings to deliver continuous amount of hydrophilic antiviral drugs that could be effective for neutralizing the viral load of HIV-1 or herpes simplex virus present in semen,” the researchers wrote.
Along with extending investigation of the vaginal rings into clinical trials, Memmi said further research also could introduce anti-inflammatory agents to the manufacturing of these devices. – by Dave Muoio
Memmi M, et al. Abstract H-775. Presented at: Interscience Conference on Antimicrobial Agents and Chemotherapy; Sept. 17-21, 2015; San Diego.
Disclosure: The researchers report no relevant financial disclosures