抗艾滋病药物初步处理有效

A new study of a drug that's been used as a last resort against HIV, the virus that causes AIDS, shows that it's as effective in initial treatment as the drug that's typically prescribed, and produces fewer side effects.

Infectious disease specialist Jeffrey Lennox and his colleagues at Emory University in Atlanta, Georgia, wanted to see how this newer drug, called raltegravir, would work in infected patients who had not yet taken medications for HIV.

"What the study showed was that for people that had never been treated before, a [drug] combination that included raltegravir was as effective as a combination that included efavirenz, and efavirenz is considered the standard of care at this point," Lennox says. "In addition, raltegravir in general had less side effects and was better tolerated than efavirenz."

Availability of HIV treatments

The issue of cost also plays a large role in determining which drugs health organizations recommend, according to Lennox. "In the past, for instance, efavirenz wasn't used because it was more costly than another drug called nevirapine. But now the price of efavirenz is going down in Africa so they're switching to efavirenz in many countries."

Similarly, the higher cost of raltegravir has limited its use in certain parts of the world, Lennox says. "At some point in the future if raltegravir becomes cheaper, then they might use it more widely. But right now it's really not available for most patients."

WHO proceeding with caution

Though the raltegravir study suggests a new use for the anti-HIV drug, other scientists are advising caution. Marco Vitoria of the World Health Organization says the study's short, 48-week span leaves some important unanswered questions: "You don't have studies for long term use. Then nobody can really be sure that there's no risk of a long term side effect that is not detected in trials yet."

But Vitoria acknowledges that raltegravir is still important for patients who've developed resistance to other drugs. "Patients that have previous experience with other drugs, without other options for treatment, certainly the drug is a good option," he says.

The next step will be to conduct longer term studies. Lennox's research is published in the journal, The Lancet .