Clinical Symptoms Enough to Switch Drug Regimens for HIV Patients

THURSDAY, April 24 (HealthDay News) -- Decisions on switching to a second-line series of drugs for HIV/AIDS patients who are failing the first-line regimen are often made on the basis of sophisticated and expensive lab tests.

But a new study shows that survival is only slightly affected if these decisions are based instead on the appearance of clinical symptoms.

Researchers still need to develop less expensive versions of laboratory tests currently used, but lack of test availability shouldn't affect access to highly effective drugs in poorer nations, said the authors of a study in this week's issue of The Lancet.

"I hope that the findings will reassure health policy makers and clinicians that they should continue to make every effort to widen access to ART and not allow any concerns over lack of laboratory monitoring to inhibit this," said study author Andrew Phillips, a professor of epidemiology at Royal Free and University Medical School in London.

The World Health Organization (WHO) recommends that, in lower-income areas, decisions regarding drug treatment for HIV be based on symptoms and, when available, CD4 cell count, rather than viral load.

With viral load, switches to second-line treatment occur when the viral load exceeds 500 copies per millileter.

CD4 cells are a type of immune system cell. Patients generally switch to the second-line drugs when CD4 counts in the blood drop 50 percent from their highest.

WHO-recommended first-line treatment consists of the antiretroviral drugs Zerit (stavudine), Epivir (lamivudine) and Viramune (nevirapine).

Using a computer simulation model to analyze how antiretroviral therapy influences HIV infection, the researchers compared survival rates, switch of second-line medication regimens and development of resistance for three different strategies: monitoring viral load and CD4 cell count or clinical observation.

Over a period of five years, 83 percent of patients using the viral load monitoring strategy, 82 percent using CD4 cell count monitoring, and 82 percent using clinical monitoring survived.