Dual-Protection TechnologiesWhat are Dual-Protection Technologies?
Dual-protection technologies are gels, intravaginal rings (IVRs), or barrier devices used with a gel or film that have a combination of contraceptive, microbicidal and/or anti-sexually transmitted infection (STI) properties with different mechanisms of action that act to prevent pregnancy, HIV and/or STIs.
The Need for Dual-Protection
A significant number of women, especially in developing countries, need protection from STIs, in particular HIV/AIDS, as well as family planning methods to prevent unplanned pregnancies.
Today, 33.3 million people are infected with HIV, with most of those infected living in developing countries, especially sub-Saharan Africa. In 2009, there were 2.6 million new infections and 1.8 million deaths due to HIV/AIDS. Women account for more than one-half of HIV infections, with the majority of infections transmitted via sexual intercourse.
Worldwide, 40% of all pregnancies are unintended. Each year there are approximately 42 million abortions, of which 35 million occur in developing countries. Many of these abortions occur under unsafe conditions, leading to 70,000 maternal deaths and 5 million women suffering temporary or permanent disabilities each year. Pregnancy and childbirth are often dangerous for women in developing countries, with hundreds of thousands of women dying each year and many more suffering serious injury or disability as a result of childbirth.
Development of Dual-Protection Technologies at CONRAD
CONRAD has been on the forefront of developing dual-protection technologies that prevent unplanned pregnancies and protect against HIV/AIDS or other STIs. Product development efforts are focused on developing IVRs because they are ideal delivery systems, providing controlled drug release over an extended period of time with just one application and potentially improving adherence and ultimately, effectiveness. Current efforts are focused on:
Contraceptive Microbicide: Levonorgestrel (LNG)/Tenofovir (TFV)-Releasing IVR
LNG is a 19-nortestosterone derivative of proven safety and efficacy. It is available in the market in different dosage forms including an LNG-releasing intrauterine system, which releases LNG directly into the uterine cavity at a constant rate of 20 µg per day. Data indicate that release rates of LNG from an IVR are adequate to achieve contraceptive efficacy, with a clinical study of 1,000 women using an LNG IVR releasing 20 µg per day for 1 year having a pregnancy rate of 3.6%. TFV prevents HIV replication in susceptible cells; it is the first microbicide proven to be efficacious in humans, with the CAPRISA 004 clinical trial showing that women using TFV gel reduced their risk of HIV infection by 39%. CAPRISA 004 also showed TFV gel to be 51% effective in reducing the transmission of herpes simplex virus-2 (HSV-2), making this combination ring potentially triple protective. CONRAD scientists are optimizing ring design to achieve desired drug release rates, aiming for a 90 day duration; two rings with different drug release rates will be prepared for clinical evaluation.