- BARCELONA, Spain (Reuters)
- Drug resistance has returned as a mounting problem in HIV/AIDS treatment,
after a brief lull in the late 1990s, according to new figures released
- The introduction of triple-drug therapies in the mid-1990s
revolutionized the treatment of the killer disease for thousands of those
infected in Western countries, allowing them to return to relatively normal
- But the virus is fighting back by evolving new ways to
circumvent medicines. A growing number of people are being infected with
strains that are already resistant to one or more of the three widely used
classes of antiretroviral drugs.
- Dr. Frederick Hecht of San Francisco General Hospital,
speaking to reporters before the opening of the week-long conference in
Barcelona on acquired immune deficiency syndrome (AIDS), saw a rising danger
- If people believe the human immuno-deficiency virus (HIV)
that causes AIDS can be easily kept at bay by popping a few pills, they
could be putting themselves at risk, he said.
- "There has been a decrease in caution about avoiding
HIV infection and an increase in riskier sexual behavior...on the assumption
that HIV is much (more) readily treated now," he said.
- "That idea needs to be called into question because
some people are becoming infected with (a strain of) virus that is going
to be much more difficult to treat," Hecht said.
- INCREASE FROM ZERO TO 13.2 PERCENT
- In a five-year study of 225 patients with recently acquired
HIV infections, Hecht and his colleagues found 16 percent of new cases
were now caused by a strain of virus resistant to at least one drug class.
- Resistance to non-nucleoside reverse transcriptase inhibitors
-- a widely used and potent type of AIDS medicine -- had increased from
zero to 13.2 percent from 1996-97 to 2000-01.
- At the same time, genetic fingerprinting of the virus
found in patients' blood showed that resistance to protease inhibitors
had grown from 2.5 to 7.7 percent.
- Meanwhile, resistance to the original class of anti-AIDS
drugs, known as nucleoside reverse transcriptase inhibitors and including
AZT, had shown an alarming increase to 21 percent, after dipping to seven
percent in 1998-99.
- The results were published in a special edition of the
Journal of the American Medical Association.
- Hecht said San Francisco was in the vanguard of HIV/AIDS
treatment, so the worrying trend of rising drug resistance was likely to
be replicated elsewhere.
- "I think we are going to see continued increases
(in resistance) over the next two years," he said.
- The problem could have particular implications in developing
countries, many of which are expected to rely heavily on combinations of
relatively cheap reverse transcriptase inhibitor drugs rather than more
expensive protease inhibitors.
- In the United States, the issue of drug resistance was
forcing doctors to test ever more complex regimes.
- Dr. Scott Hammer of Columbia University College of Physicians
and Surgeons in New York City reported on another clinical trial showing
for the first time that adding two protease inhibitors, rather than just
one, to drug cocktails could help patients who had failed to respond to