WASHINGTON -- Physicians should no longer automatically prescribe the anti-viral drug AZT to HIV-infected individuals whose immune systems have begun to deteriorate but who have not developed symptoms of acquired immune deficiency syndrome, a federal advisory panel has concluded.
The recommendation, completed late Friday, represents a major departure from current medical practice, which has been to give AZT routinely to patients without AIDS symptoms whose immune system cell count has fallen below a certain level.
Instead, doctors should discuss with their patients the best time to begin administering the drug, weighing its side effects and other factors along with recent findings that threw doubt on the long-term survival benefits of taking the drug at an earlier stage.
The panel's recommendations, while not federal policy, are intended to give physicians guidance in treating adults who are infected with the human immunodeficiency virus, or HIV, which causes AIDS. The new guidelines are expected to be treated seriously by the nation's physicians and will likely alter the way AZT is prescribed today for many infected patients.
Panel members "are saying, 'Hey, wait a minute. It isn't an automatic thing anymore. There are now pros and cons,' " said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, who did not serve on the panel but whose agency convened the meeting.
"With such advice and counsel, patients and their care givers can make the most informed decisions about whether to begin, change or combine therapies," Dr. Fauci added.
Doctors now generally prescribe AZT to patients whose CD4 immune system cells have fallen below 500 per cubic millimeter of blood, compared with a normal range of 800 to 1,200. At the 500 level, patients become vulnerable to the so-called opportunistic infections that eventually kill people with AIDS.
Studies have shown that taking the drug at this point can delay the onset of these symptoms. However, the results of a large study released earlier this month demonstrated that patients who took AZT at this stage ultimately lived no longer than those who started taking it after they became sick.
The new recommendation means that patients, working with their doctors, must attempt to strike a critical balance.
They will have to weigh the potential benefits of taking the drug at an early stage against the possibilities of experiencing toxic side effects and drug resistance -- along with the knowledge that they will likely live no longer than those who wait.
AZT, the most widely prescribed AIDS anti-viral drug, has shown benefits for most AIDS patients regardless of when it is taken, but researchers had hoped that earlier intervention would result in longer life.
Studies have shown that in addition to delaying the onset of AIDS in people who are not showing symptoms of disease, AZT has also helped patients with fully developed AIDS who start the drug after developing symptoms. In these patients, AZT has resulted in fewer episodes of infection and other improvements, such as increased weight gain.
However, AZT can cause serious toxicities -- among them anemia, headaches and gastrointestinal problems -- and patients also can develop resistance to the drug.
Also, some researchers think patients who take AZT earlier in infection become sicker once they develop symptoms than those who start AZT after they become ill.