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Sau khi Ủy ban các chuyên gia cố vấn của FDA chứng nhận thuốc Truvada có tác dụng phòng ngừa lây nhiễm HIV qua đường quan hệ tình dục, loại thuốc này đã được FDA chính chức phê chuẩn. Đây loại thuốc phòng ngừa HIV đầu tiên được FDA công nhận.
FDA nhấn mạnh rằng thuốc Truvada chỉ nên được sử dụng như một phần của kế hoạch phòng phòng chống HIV một cách toàn diện, bao gồm các phương pháp khác như sử dụng bao cao su trong quan hệ tình dục và xét nghiệm HIV định kỳ.
Kết quả các nghiên cứu trước đó cho thấy thuốc Truvada, được sản xuất bởi công ty Gilead Sciences có trụ sở ở California (Mỹ), có khả năng phòng nguy cơ lẫy nhiễm HIV qua quan hệ tình dục từ 44% đến 73%.Trước đó, Truvada cũng đã được FDA ủng hộ để sử dụng cùng với một số loại thuốc kháng virus trong điều trị cho những người đã nhiễm HIV.
Tuy nhiên, một số chuyên gia lo ngại rằng việc những loại thuốc phòng virus HIV như Truvada có thể khiến mọi người chủ quan trong việc phòng tránh căn bệnh nguy hiểm này. Ngoài ra, loại thuốc này có thể khiến các chủng virus HIV kháng thuốc phát triển.
Theo BBC
Approval Prompts Call for Tougher Rules on HIV Drug
By Amy Dockser Marcus
- Getty Images
In the hopes of preventing the spread of HIV, the FDA today approved the use of the drug Truvadafor healthy people who are at high risk of becoming infected by partners with the virus that causes AIDS.
Although the move was hailed by many as an important step in the fight against AIDS, concerns that people will incorrectly use the drug — potentially spurring drug resistance — led others to blast the agency for not laying down tougher rules.
Instead of requiring that people prove they are HIV negative before getting a prescription filled, the FDA slapped a boxed warning on the drug, saying it must only be used by people who have a confirmed HIV-negative test prior to getting a prescription, and then get tested at least every three months while they are using it.
The drug, the FDA stated in a press release, is “contraindicated” for prevention in people with unknown or positive HIV-status. “The FDA strongly recommends against such use,” the press release stated.
But this wasn’t enough for some the AIDS community.
In a media call after the decision was announced, the AIDS Healthcare Foundationcalled the FDA decision “a catastrophe in the fight against HIV in America” and said it was likely to lead to more, not fewer, HIV infections.
The organization has opposed FDA approval for Truvada’s use in preventing HIV in healthy people. Gilead Sciences is the maker of Truvada, which was already approved to treat people who are infected with HIV.
Michael Weinstein, co-founder and president of the AIDS Healthcare Foundation, later told the Health Blog that healthy people should be required to show proof of a negative HIV test before getting Truvada as a prevention medicine.
“If it’s that important, why isn’t it a requirement?’’ he said. There is a precedent, he says: Women must test negative for pregnancy and are required by the FDA to participate in a risk management program before, during, and after using isotretinoin to treat severe acne, because the drug can cause birth defects.
Debra Birnkrant, the director of FDA’s division of antiviral products, said during a press call that the agency didn’t want to set up a system that would require patients to show proof of a negative HIV test because it didn’t want to inadvertently “hinder access to those who need it for treatment.”
Weinstein says 21% of HIV-positive people in the U.S. don’t even know it because they feel fine and don’t get tested. If they take Truvada as prevention, there is a possibility that the HIV strains they have could become resistant to treatment — and that they might spread these strains unknowingly to their partners. If someone skips doses of Truvada, something that was an issue even in the clinical trials, this might also lead to infection and the possible emergence of drug-resistant HIV strains.
Other people might get an HIV test before starting Truvada but continue to get the drug refilled without having HIV testing done every three months as the FDA recommends. “Many times pharmacies call doctors for approval to renew, and drugs get routinely renewed over and over again,” Weinstein said.
Howard Jaffe, president of the Gilead Foundation, the philanthropic arm of Gilead Sciences, tells the Health Blog that getting tested for HIV is the “absolute cornerstone of any successful prevention program.” He adds that the FDA’s recent approval of the first rapid at-home HIV test will make it easier to get tested.
One of the conditions of the FDA approval is that Gilead has to collect viral strains from people who become infected with HIV while taking Truvada and test them for any signs of drug resistance. The FDA also said in its statement that Gilead must run a trial to evaluate, among other issues, drug adherence and its relationship to whether someone who becomes HIV positive while using Truvada for prevention shows signs of drug resistance.
Jaffe says the company held more than 10 focus groups around the country including activists, public-health authorities, patients and others to discuss the many issues. One key concern that got raised, he said, was that “introducing a gating mechanism” at the pharmacy may have negative consequences for people already getting Truvada for treatment.
“The last thing we want to do is decrease ease of access for those getting treated (for HIV infection),” he adds.