University of Washington researchers have come up with a whole new way to deliver HIV-killing microbicides: a dissolving tampon.
The idea is that one day a woman may be able to discreetly insert the product minutes before sex in order to protect herself against the virus. Studies in South Africa have already shown that using microbicide gels as PrEP, or pre-exposure prophylaxis, can reduce HIV transmission by about 54 percent.
Effectiveness depends on applying the products consistently. The problem with topical microbicide gels applied with an applicator is that they require a very large dose and, as a result, medication may leak out before it can be absorbed by the body.
Now, doctoral student Cameron Ball has teamed up with assistant bioengineering professor Kim Woodrow to create a better way to deliver the microbicide's virus-killing punch. Tampon fibers made using a new process called electrospinning can retain a massive dose of microbicides, yet dissolve inside the vagina in as little as six minutes.
Delivering microbicides in tablets or films is a possibility, but those can take more than 15 minutes to dissolve, according to Ball and Woodrow's research.
Their work has been published in Antimicrobial Agents and Chemotherapy. The next step is to test the product on rabbits for safety and effectiveness.
An Alternative to Oral PrEP?
Ball said he believes the team can get funding for such trials. He also expects promising results. The polymer fibers used in the tampons are already widely used in the pharmaceutical industry, he said. And they used the microbicide maraviroc (Selzentry) in their research, which is already FDA-approved.
Even if all goes well, the final product is still at least three years away, Ball told Healthline.
PrEP for HIV already exists in the form of a once-daily pill called Truvada, but uptake of the drug has been slow.
The researchers would ideally like to develop a tampon to protect against HIV, herpes, and pregnancy — an all-in-one shield against the risks of sex. This could prove especially useful in developing countries, where women may not have easy access to other kinds of birth control.
Discretion Is the Name of the Game
Ball said gynecologists and patients he's spoken with have given the dissolving tampon their seal of approval. “Everyone gets excited when they hold it,” he said.
Ball said the team at the University of Washington is even working on creating a version of their product for rectal use, though it is a challenging technical task.
Ultimately, Ball and the other researchers want to create HIV prevention tools that can be used discreetly. There is so much stigma surrounding HIV and PrEP that many people are discouraged from using PrEP drugs, he said.