Study at USP will test injectable Prep for HIV prevention

An international study with the participation of the Faculty of Medicine of USP (University of São Paulo) will test a new form of injectable Prep (pre-exposure prophylaxis) for HIV prevention. The expectation is that, with different methods of protection, it will be easier to reach a greater number of people who use some form of prevention.

Brazil already has the Prep model in tablet provided free of charge by the Ministry of Health. The device involves taking every day a capsule formed by the antiretrovirals tenofovir and emtricitabine, drugs that are effective against HIV.

So, if someone is exposed to the virus, it will not be able to replicate in the person’s body. “The idea is not to let the virus multiply, because that way the immune system can eliminate it”, says Rico Vasconcelos, an infectious disease specialist, researcher at the USP School of Medicine and research coordinator at the university.

Studies have already demonstrated the effectiveness of the method. One of them concluded that Prep reduced the incidence of HIV by 95% in participants with detectable blood levels, that is, with constant adherence to prevention.

However, the need to take the pill daily can be a deterrent for some users. “The performance of Prep in real life is not the same in all groups because of the low adherence that some people have”, says Vasconcelos.

Therefore, the development of new preventable prophylaxis is important in order to increase the range of options for combination prevention, the concept of having a wide range of ways to avoid HIV infection.

“The best prevention methods for each are those that people choose and that the person is able to use correctly and consistently”, he says.

A possible way to improve adherence to Prep is the injectable versions of antiretrovirals, as they demand longer applications. The case of the research with the participation of USP is based on the antiretroviral lenacapavir, with a subcutaneous injection every six months.

For treatment, injectable lenacapavir has already shown positive results, however there is no evidence on the effects of preventing the virus – this is the main objective of the new research.

The clinical study is in phase 3, the last stage in the search for new drugs. The researchers are currently in the participant recruitment stage. In all, it is expected to reach a total of 3,000 volunteers.

HIV in Brazil

Vasconcelos explains that Brazil, in comparison with other Latin American countries, has a more structured system for HIV prevention and treatment. Even so, challenges still exist, such as racial inequality in access to health services.

“Among white women and men, we have a detection rate of new cases and death from AIDS that drops over time, this is not repeated among blacks. This shows that we have unequal access to health care in Brazil with this racial determinant”, explains the researcher.

In addition, the vast majority of Prep tablet users are gay, white, college-educated men. “It is good that they are taking it, but this also points to social inequality in access to health”, he adds.

The researcher also has concerns about the forecast of cuts of R$ 407 million for the prevention, control and treatment of HIV/AIDS and other infections. “How will a scrapped program with no money perform? Will we still be an example country in Latin America? Everything points to not”, he concludes.