HIV/AIDS Newsroom: January 30, 2001
The Doctor's World; The AIDS Questions That Linger
New York Times (www.nytimes.com)
01/30/01; P. F1; Altman, Lawrence K.
"Where did AIDS come from?" Perhaps the most profound in a list of basic questions that remain unanswerable even after the nearly twenty years of research into the disease. HIV, the virus that causes AIDS, ranks as one of the world's most devastating epidemics, killing at least 21 million people and infecting 36 million to date. Dr. Peter Piot, director of the United Nations AIDS Program (UNAIDS), and other experts believe that scientists could learn much more about HIV and other infectious diseases by careful examination of the unanswered questions. Over the years, many scientists have stayed within their own fields of specialization, narrowing their focus into isolated facets of HIV research, leaving many of the larger unknowns still untouched. Unable to find real consensus on any one idea, broad scientific questions about HIV remain open as scientists continue to commit themselves to finding a solution, a definitive way to eradicate the disease for good. "Is a vaccine possible?" In 1984, when HIV-1 was discovered, the Secretary of Health and Human Services promised a vaccine would be found within a few years. In the 17 years that have passed, little progress has been made due in part to the complications presented by mutated strains of HIV, rendering any one type of vaccine ineffective. Realistically, vaccines in existence today for other diseases only protect 90 percent of the recipients. Considering that an HIV vaccine would predictably only protect a significantly lower percentage of recipients, a question remains of at what level health officials decide that the percentage is high enough to license the vaccine.
Drug companies Trimeris and Roche Holding, both of which are working on a new class of AIDS drugs designed to help patients who develop resistance or intolerance to the disease's standard treatment, are reporting that six small studies have shown patients to respond favorably to their products. The companies' new drugs, called T-20 and T-1249, bind to the AIDS virus outside the cell and prevent it from ever entering the cell and infecting it. Current AIDS treatment involves a cocktail of antiretrovirals, three classes of drugs that use different means of preventing the virus from reproducing once inside the cell. According to Dani Bolgnesi, chief executive of Trimeris, 300,000 patients worldwide will probably have developed a resistance or intolerance to the cocktail by 2002. The results for all six studies will be released in a week at a major medical conference. Two 500-patient, Phase III trials of T-20 are also being conducted both in Europe and the United States, the results of which should be available next year. Phase III trials are necessary for the drugs to receive federal approval.
Kenya Population Up by a Third in Decade to 1999
Kenya's population increased by a third to 28.7 million in the decade to 1999, while mortality increased due to AIDS-related deaths, especially among young children. Official figures released by the Kenyan government Monday estimate that 2.2 million Kenyans are infected with HIV, 106,000 of them children.
Drugmaker Merck announced Jan. 29 that the U.S. Food and Drug Administration has approved its experimental drug Cancidas, promising people with weakened immune systems a treatment for invasive Aspergillosis. Cancidas, which is the first member of a new class of medicines that are meant to stem the growing onslaught of deadly fungal diseases becoming common in people with weakened immune systems, is intended for extremely ill individuals who have not benefited from other therapies. When contracted by cancer patients, organ and bone marrow transplant recipients, patients with HIV/AIDS, and others with weakened immune systems, Aspergillosis can infect the lungs and spread throughout the body to damage the heart, brain, kidneys, and eyes. Because the drug is designed for patients with no other hope, pharmaceutical analysts expect most doctors will shelve it for emergency use, rather than prescribe it as a first-use treatment. Merck is expected to achieve peak annual sales between $300 million and $500 million on the product.
Japanese scientists recently concluded that methods currently being used to extract HIV from infected sperm are not significantly effective enough to consider using the sperm in artificial insemination. The scientists, headed by Shinichi Oka, section chief of the International Medical Center of Japan's AIDS Clinical Center in Shinjuku Ward, Tokyo, began to examine the two current techniques being used -- one method being the separation of healthy sperm from infected sperm, and the other, isolating the sperm from the virus and the lymphocytes, which are particularly susceptible to infection. Tests showed that even when using a combination of both techniques, at least four of nine samples remained HIV-positive afterward. The groups' report will be published in the February issue published by a society of AIDS specialists.
The Department of Health and Human Services' blood-safety advisory committee has recommended that the Food and Drug Administration (FDA) require white blood cells to be filtered out of all donated blood, which could make transfusions less of a risk for some people, but which could also cost the United States half a billion dollars per year. FDA officials have indicated that they support the idea. Leukoreduction, the removal of leukocyte white blood cells from transfusable blood, is done for certain patients -- AIDS patients, premature infants, cancer patients, and those who need repeated transfusions -- because of the risk of a virus that can hide in white cells. They also risk an anti-leukocyte reaction that can reduce the effectiveness of future transfusions. Those who need transfusions need them for the red blood cells, not the white. Between 20 percent and 40 percent of the blood supply is leukoreduced for the at-risk patients. Some scientists say that the filtered blood is safer, while others counter that there is no evidence that filtered blood benefits the average recipient and say that the $40 or so extra per transfused blood unit should be used to fight other risks. Meanwhile, filter makers are encouraging the controversy in hopes of increasing sales. The reasoning behind the committee's recommendation is that filtering all blood would avoid errors of unfiltered blood going to sensitive patients. Advocates also say that filtered blood may provide more benefits than presently known. However, filtering can reduce the number of red cells by 10 percent or so, and the nation is already in the middle of a blood shortage. The committee recommended gradual filtering to minimize blood shortages.
AIDS in Africa will nearly destroy the continent's economy, may cause war, and is killing millions of people each year. Such a severe plague has not been seen since Europe's 14th century Black Death, and it has taken 17 million lives so far -- with more to come. Meanwhile, AIDS is racing through other areas, including India, the Caribbean, Eastern Europe, and the former Soviet Union, among others. Until recently, the triple drug therapy used to control AIDS was considered realistic only for the wealthy or those in societies that could pay for the drugs for victims. Poorer nations could only try to prevent new cases and treat some infections. Now, however, things are changing. In Brazil, poor AIDS patients get antiretrovirals for free, and have since 1997. The country has built a network of AIDS clinics and has proven that its uneducated population is quite able to take medicine on time. Brazil's treatment program has cut in half the AIDS death rate, prevented many new hospitalizations, reduced the transmission rate, helped to stabilize the epidemic, and has improved the general state of public health. The nation can afford all the drugs because it does not pay market prices -- it copies brand-name drugs, reducing the price by an average 79 percent. Various international organizations are beginning to help countries try to reproduce Brazil's program, and Brazil has offered technology and training to other nations that will supply the drugs to patients for free. Meanwhile, the drug companies are beginning to make limited offers of cheap drugs. Other countries can reproduce Brazil's success with international help.
This past summer statistics issued by the San Francisco Department of Public Health garnered much attention when they indicated a nearly three-fold increase in new HIV infections in the city, to 900. However, a report issued in September indicated that the number of new HIV cases was between 500 and 600. Furthermore, while there were rumors at the time of the first report of a high rate of rectal gonorrhea among gay men, the data -- which had been inadvertently omitted from the first report -- revealed a decrease in the per capita infection rate. The raw number of cases had increased, however.
This article was provided by CDC National Prevention Information Network. It is a part of the publication CDC HIV/Hepatitis/STD/TB Prevention News Update.