Survey Finds 122 New Anti-HIV Medicines Currently Being Tested

WASHINGTON--A new survey of pharmaceutical and biotechnology companiesby the Pharmaceutical Research and Manufacturers of America (PhRMA) hasidentified 122 drugs and vaccines in testing to prevent HIV infection orto treat AIDS and AIDS-related diseases. These drugs are in addition tothe 42 medications already approved and on the market in the United States.

The number of medicines in development increased by 12 from the 110reported a year ago, the trade association said. The number of drugs onthe market increased by 8 during the same period, from 34 to 42.

A breakdown of the medicines and vaccines now in development shows that41 are antiviral agents. Anticancer agents account for 19; anti-infectiveagents, 18; vaccines, 13; immunomodulators, 10; and gene therapy approaches,four. Another 17 new pharmaceuticals fall into the "others" category.

"These potential new AIDS medicines use both new and already provenapproaches to stopping or mitigating the disease," said PhRMA PresidentAlan F. Holmer. "The progress already made against AIDS is quite remarkable,given the fact that the first US cases were reported in 1981, and the viruswas only identified in 1983."

One of the anticancer drugs, Zyrka-mine (mitoquazone, ILEX Oncology/SanofiWinthrop) has been submitted to the FDA for approval for use against AIDS-relatednon-Hodgkin's lymphoma, noted John D. Siegfried, PhRMA's deputy vice presidentfor regulatory and scientific affairs.

"Scientists are becoming increasingly optimistic about the prospectsfor turning AIDS into a manageable chronic disease," Dr. Siegfriedsaid. "Their optimism appears justified."

He noted several reasons for this more hopeful outlook:

• Over the last four years, new medicines have doubled the life expectancyof people infected by HIV.
• The increasing variety of today's AIDS medicines are proving increasinglyuseful against the HIV problem. These include new immunomodulators to boostthe body's immune system, 10 of which are now in testing in humans.
• The new protease inhibitor drugs, which interfere with the proteinthat HIV needs to replicate, have lowered the HIV viral content in theblood of some patients by up to 99%. Protease inhibitors prove most effectivewhen they are used as part of a three-drug "cocktail."

Research reported at the Third International Congress on Drug Therapy,held in Birmingham, England, is even more encouraging, Mr. Holmer said.Researchers from the University of Amsterdam reported that combinationdrug therapy eradicated the AIDS virus, not only from the blood of infectedindividuals but also from the tonsillar tissue.

"This is important new information," he said, "becauseit had been feared that small amounts of HIV would 'hide' in a patient'scells, such as in tonsillar lymphoid tissue, escaping detection."

While commenting that the cocktail combination therapy is expensive,costing between $10,000 and $16,000 per patient per year, Mr. Holmer alsostressed the cost of treating an HIV-infected person who progresses toAIDS. "It costs an estimated $100,000 a year to treat a patient withfull-blown AIDS in a hospital," he said. "In the long run, thesedrugs will not only save lives, they will save money, too."

Besides new drugs, scientists have developed new tests to gauge theamount of HIV virus in the body. Said Dr. Siegfried: "The new testsare important because they help doctors determine how effective a particulardrug is and when it may be necessary to change therapy."