The ultimate goal of this Program is to develop an intravaginal ring (IVR) for sustained delivery of a combination microbicide that will be safe and effective in preventing the sexual transmission of human immunodeficiency virus (HIV) and herpes simplex virus (HSV). A safe and effective microbicide will likely require sustained, local delivery of a combination of antiretroviral drugs that target different steps in the HIV life cycle and a delivery system that overcomes the challenges related to adherence. This will be accomplished through IVR formulation of the reverse transcriptase inhibitor, tenofovir disoproxil fumarate (TDF), combined with the entry inhibitor, maraviroc (MVC). The rationale for pursuing this combination is based on the recent promising results of CAPRISA 004 in which significant protection against HIV-1 and HSV-2 was observed with 1% TFV gel. Ongoing work in Projects 1 and 2 demonstrate potential advantages of a TDF compared to a TFV IVR, including more potent activity against HIV and HSV, greater tissue permeability, and the successful development of a polyurethane (PU) IVR formulation of TDF. An exploratory pre-Phase I study is proposed in this new Project to rigorously measure the pharmacokinetics (PK), pharmacodynamics (PD) and safety of TDF following ring delivery in healthy women. The primary outcomes to be measured are PK of TDF release into the genital tract and adverse events. PD will be evaluated by measuring the antiviral activity (HIV and HSV) in genital tract secretions (luminal) and tissue following IVR delivery of TDF. Ectocervical tissue will be challenged ex vivo with virus to assess drug bioavailability and activity. The impact of PU IVRs on the mucosal immune environment will be assessed by quantifying immune cell populations in the genital tract and concentrations of inflammatory, anti-inflammatory and soluble mucosal immune mediators in genital tract secretions. Advanced molecular microbiological tools will be employed including broad range 16S rRNA gene PCR with pyrosequencing to define the bacterial communities, and fluorescence in situ hybridization to determine if rings alter the epithelium and lead to vaginal biofilm formation. Results will inform the design of a Phase I trial of a TDF-MVC combination IVR.
The development of a topical microbicide to prevent the sexual transmission of HIV and herpes is an urgent social need. The goal of this project is to assess the safety of a vaginal ring containing tenofovir disoproxil fumarate, which has the potential to save millions of lives.
|Keller, Marla J; Mesquita, Pedro M; Marzinke, Mark A et al. (2016) A phase 1 randomized placebo-controlled safety and pharmacokinetic trial of a tenofovir disoproxil fumarate vaginal ring. AIDS 30:743-51|
|Rastogi, Rachna; Su, Jonathan; Mahalingam, Alamelu et al. (2016) Engineering and characterization of simplified vaginal and seminal fluid simulants. Contraception 93:337-346|
|Teller, Ryan S; Malaspina, David C; Rastogi, Rachna et al. (2016) Controlling the hydration rate of a hydrophilic matrix in the core of an intravaginal ring determines antiretroviral release. J Control Release 224:176-183|
|Smith, James M; Srinivasan, Priya; Teller, Ryan S et al. (2015) Tenofovir disoproxil fumarate intravaginal ring protects high-dose depot medroxyprogesterone acetate-treated macaques from multiple SHIV exposures. J Acquir Immune Defic Syndr 68:1-5|
|Srinivasan, Priya; Dinh, Chuong; Zhang, Jining et al. (2014) Pharmacokinetic evaluation of tenofovir disoproxil fumarate released from an intravaginal ring in pigtailed macaques after 6 months of continuous use. J Med Primatol 43:364-9|
|Teller, Ryan S; Rastogi, Rachna; Johnson, Todd J et al. (2014) Intravaginal flux controlled pump for sustained release of macromolecules. Pharm Res 31:2344-53|
|Nixon, Briana; Jandl, Thomas; Teller, Ryan S et al. (2014) Vaginally delivered tenofovir disoproxil fumarate provides greater protection than tenofovir against genital herpes in a murine model of efficacy and safety. Antimicrob Agents Chemother 58:1153-60|
|Herold, Betsy C; Dezzutti, Charlene S; Richardson, Barbra A et al. (2014) Antiviral activity of genital tract secretions after oral or topical tenofovir pre-exposure prophylaxis for HIV-1. J Acquir Immune Defic Syndr 66:65-73|
|Nixon, Briana; Stefanidou, Martha; Mesquita, Pedro M M et al. (2013) Griffithsin protects mice from genital herpes by preventing cell-to-cell spread. J Virol 87:6257-69|
|Mesquita, Pedro M M; Srinivasan, Priya; Johnson, Todd J et al. (2013) Novel preclinical models of topical PrEP pharmacodynamics provide rationale for combination of drugs with complementary properties. Retrovirology 10:113|
Showing the most recent 10 out of 21 publications