Paris (AFP)

Fewer tablets to treat HIV, an effective implant one year to avoid contamination ... The scientific conference on AIDS (IAS) that ends Wednesday in Mexico City was an opportunity to present several improvements for the lives of patients and prevention in people at risk.

Soon an effective anti-HIV implant a year?

In recent years, the concept of preventive treatment, or pre-exposure prophylaxis (PrEP), has revolutionized prevention against the AIDS virus.

Proposed primarily to populations at risk, such as homosexuals with unprotected sex or prostitutes, taking an antiretroviral drug to avoid being contaminated has proven its effectiveness but remains restrictive.

In the future, it may be possible to obtain the same result without taking continuous treatment or before each risk report (PrEP "on demand"), thanks to a "long-acting" implant.

The first human trial, described by the IAS as "preliminary but promising", established after 12 weeks of use that it was well tolerated by the 16 participants and that it delivered the expected dose of medication.

According to its author, researcher for the American laboratory Merck & Co, the implant could continue to broadcast a sufficient dose for "at least a year".

New studies will have to be done to show if this implant offers the same level of protection against HIV as oral medication.

Such an implant "could be a promising solution for those who have trouble adhering to a daily treatment," commented Anton Pozniak, president of the IAS.

The conference was also an opportunity to present a new study on the acceptance and efficacy of intravaginal ring PrEP, which delivers an antiretroviral drug, dapivirine, for one month.

"We are creating new tools that adapt to the realities of the people," said Anton Pozniak.

Tablets every other day?

Many projects also seek to reduce the daily lives of HIV-positive patients and reduce the cost of their treatment while keeping the virus dormant.

By 2020, antiretroviral injections should be enough to replace daily tablets with a weekly sting.

Another track presented to the IAS is not to take triple therapy every day but every other day or less.

The French study Quatuor conducted by the National Research Agency against AIDS (ANRS), whose results will be released Wednesday, will show whether taking tablets four days out of seven keeps the same level of effectiveness.

Reducing the "drug burden" of HIV-infected people could also include switching to two molecules (dual therapy) rather than three. Two studies also unveiled Wednesday in Mexico sought to establish the safety and effectiveness of such a regime.

New reassuring data on an innovative drug

New data have been presented on the use of dvrutegravir antiretroviral (DTG) in pregnant women and those of childbearing age.

This drug, marketed by ViiV Healthcare (the GSK group) under the name Tivicay and in generic form, has been in the hot seat since last year, after the publication of a study in Botswana highlighting the risk of brain malformations and the spinal cord in the children of women treated with this molecule (4 cases out of 426 pregnancies).

These results had created a dilemma, as DTG is one of the best currently available HIV therapies on the market, more effective and easier to use than other medications, with fewer side effects and less likely to cause side effects. development of resistances.

Complementary studies presented this week tend to show that the risk of malformations is finally "lower than reported last year," notes the IAS, with 3 births per 1,000 in Botswana - against one per 1,000 with other drugs - and none in a study conducted in Brazil.

On this basis, the WHO "highly recommends dolutegravir as the preferred choice of treatment for HIV," including women of childbearing age, "because of the enormous benefits it brings."

At the same time, the international organization stresses the importance of informing women of the risks and giving them access to family planning services.

© 2019 AFP