Nonclinical Laboratory Studies: PC-700 Series Gels (Carrageenan with Zinc Salts)
Council researchers are studying microbicide gels containing carrageenan and zinc salts that might block acquisition and transmission of herpes and HIV.
Laboratory scientists at the Population Council's Center for Biomedical Research (CBR) are developing water-based gels that contain carrageenan (a natural polymer isolated from seaweed) and varying amounts of zinc acetate to block sexually transmitted infections such as herpes and HIV in humans.
Using animal models of infection, the scientists have shown that PC-707, a gel comprising 0.3% zinc acetate and 3% carrageenan, effectively blocks both herpes infection in mice and a modified form of HIV infection in macaques (monkeys).
Zinc salts might represent a useful alternative to antiretroviral drugs (ARVs) currently in use and under investigation. They are unlikely to cause resistant strains of HIV to develop, which is always a concern with ARVs. Moreover, many zinc salts are freely soluble in water, which is not the case with many ARVs. This property makes it easier to prepare stable, water-based gels.
Council scientists also are preparing zinc gels in which carrageenan is replaced with other natural and man-made polymers. These gels might have interesting properties regarding their spectrum of activity and movement within the rectum and vagina. The scientists also are trying to determine how zinc acetate blocks herpes and HIV infection.
Council scientists are now optimizing the gels in terms of efficacy, safety, and stability. Once an optimized formulation is identified, the microbicide product development team will prepare clinical-grade material at CBR to support a Phase 1 clinical trial in humans.
Zinc acetate/carrageenan gels exhibit potent activity in vivo against high dose HSV-2 vaginal and rectal challenge (abstract)
Fernandez-Romero,Jose A.; Abraham,Ciby J.; Rodriguez,Aixa; Kizima,Larisa; Jean-Pierre,Ninochka; Menon,Radhika; Begay,Othell; Seidor,Samantha; Ford,Brian E.; Gil,Pedro I.; Peters,Jennifer; Katz,David; Robbiani,Melissa; Zydowsky,Thomas M.
Antimicrobial Agents and Chemotherapy 56(1): 358-368
Publication date: 2012
Location: United States
HIV and AIDS
Duration: 1/2000 - ongoing
Agegnehu Gettie (Aaron Diamond AIDS Research Center)
David Katz (Duke University)
James Blanchard (Tulane National Primate Research Center)
Jeffrey Lifson (National Cancer Institute)
Julian Bess (National Cancer Institute)
Michael Piatak (National Cancer Institute)
Morseth Consulting, LLC