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Indian
drug firms can survive only if they have new drugs in
their intellectual property pipeline. 
News (Updated January 8, 2005)
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Tue Jan 4, 2005 11:44 AM ET
By Philip Blenkinsop
BERLIN (Reuters) - German scientists have found a new way to prevent the HIV virus from replicating, offering hope in the face of the virus's increasing resistance to existing drugs.
Joachim Hauber, a professor at the Heinrich-Pette Institute in Hamburg, told Reuters on Tuesday his team had identified a protein in human cells that the HIV virus uses to reproduce and run tests on a chemical that blocks this protein's action.
Drugs such as GlaxoSmithKline's AZT and existing inhibitors produce drug resistance because they work on viral proteins, which can mutate when the HIV virus replicate.
Human cells are much less prone to mutations, so the German researchers believe the cellular protein they have singled out is a promising target for drugs that could avoid creating multiple resistance.
"We have identified a new possibility, but we cannot judge it yet. We are far away from a therapy," said Hauber, who heads the institute's department of cell biology and virology.
He added that it typically requires five to 10 years from test phases before a drug becomes available.
"It's not a therapy that will be available tomorrow."
Hauber, whose findings are published in this month's issue of the Journal of Clinical Investigation, said his research team had tested a particular chemical's action for 12 weeks.
The tests showed it consistently blocked multiplication and had no tendency of the HIV virus to develop any resistance. It also produced no clear toxic side-effects, a major problem in the development of medicines to fight HIV/AIDS. The chemical is an experimental drug, developed by a firm in Pennsylvania, Cytokine PharmaSciences Inc., which is in clinical trials for the treatment of Crohn's disease, a condition that causes chronic inflammation of the small intestine.
The human immunodeficiency virus, which infects about 40 million people worldwide, is incurable and leads to AIDS, although a cocktail of drugs called highly active antiretrovial therapy can suppress it and keep patients healthy for years.
Almost all anti-retroviral drugs attack the virus after it has infected the body's immune system and simply suppress replication, so patients must take the drug for life.
Thu Jan 6, 2005 02:27 PM ET
By Maggie Fox, Health and Science Correspondent
WASHINGTON (Reuters) - A gene that may help block the AIDS virus from getting into cells seems to protect some people from the deadly and incurable infection, researchers said on Thursday.
They found that people who carry extra copies of the gene are less likely to become infected with the virus, which affects 40 million people worldwide.
The findings may eventually lead to better ways to prevent and treat HIV, which has killed more than 25 million people since it was first identified in the early 1980s, said the National Institute of Allergy and Infectious Diseases, which funded the study.
It also may help explain overall human immunity against infectious diseases, the researchers write in an advance report in the journal Science.
The gene, called CCL3L1, controls production of an immune system signaling chemical, or chemokine.
Normally, genetic variation means people have slight mutations or variations in a gene, or working and non-working copies -- one copy inherited from the mother and one from the father. In this case, people actually have multiple copies of the entire gene, said Dr. Sunil Ahuja of the University of Texas Health Science Center in San Antonio, who led the study.
"About five percent of the human genome has got large chunks of sequence that are duplicated," Ahuja said in a telephone interview.
For CCL3L1, some people have no copies of the gene at all and some people have four, five and more. This chemokine is associated with a receptor -- a cellular entryway -- known as CCR5.
CCR5 is known to affect susceptibility to HIV infection and to how quickly an infected person progresses to AIDS.
STUDYING DIFFERENT ETHNIC GROUPS
For their study Ahuja and colleagues in the United States, Britain and Argentina analyzed blood samples from more than 4,300 HIV-infected and non-infected people of different ancestral origins.
They counted how many copies of the CCL3L1 gene each person had, and found big variations.
For example, HIV-negative black adults had an average of four copies of CCL3L1, while HIV-negative European-Americans averaged two copies each and uninfected Hispanic-Americans had an average of three copies.
The more copies a person had, the less likely he or she was to be infected with HIV.
And it was not the absolute number of extra copies of the gene that mattered, Ahuja's team found. Instead, it was whether a person had more copies than average for his or her ethnic group.
In general, each extra copy of the CCL3L1 offered 4 percent to 10 percent protection from the virus, Ahuja said.
About 1 percent of people of Caucasian descent have a mutation in the CCR5 gene that makes them very unlikely to acquire HIV, or to come down with AIDS once infected. That led Ahuja's team to look at chemokines that interact with CCR5.
He described infection as a battle between the virus and the body's immune system chemokines, all trying to get into immune cells called T-cells. "The virus is trying to compete with sites for chemokines," he said.
The outcome depends on how much virus is in the blood, how many CCR5 receptors a cell has and how much chemokine is around.
Dr. Matthew Dolan, an Air Force colonel at Brooks City-Base in San Antonio who worked on the study, said the finding could help doctors decide when and how to treat HIV-infected patients with cocktails of anti-viral drugs. It could also help in designing new vaccines and testing current HIV vaccines, Dolan said.
He said it was unclear if the CCL3L1 chemokine itself could be made into a treatment of vaccine.
"You don't know if varying what nature has wrought here could improve this disease or worsen some other disease," Dolan said.
Wed Jan 5, 2005 01:52 AM ET
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WASHINGTON (Reuters) - The consumers group best known for rating cars and washing machines has turned its testing prowess to condoms to find out which ones measure up best and how other birth control methods compare.
The nonprofit Consumers Union says in a new guide to contraception that the seven top U.S. types of condom they studied did not burst despite vigorous testing, and all models met international standards.
But results showed that the top brand, able to take the most punishment, was the Durex Extra Sensitive Lubricated Latex, according to the report.
Other top-performers include the Durex Performax Lubricated, Lifestyles Classic Collection Ultra Sensitive Lubricated and TheyFit Lubricated.
A melon-coloured model distributed by Planned Parenthood performed the worst, bursting during a test in which the latex condoms were filled with air.
The group says its review of contraceptives was not politically motivated, although there is an intense debate among health professionals and advocacy groups about the focus on abstinence-only education by the Bush administration.
"We plan our testing programs quite a while in advance. This is purely accidental," said senior editor Nancy Metcalf.
Consumers Union uses standardized tests to rate the products it examines, which for latex condoms involves filling them with air. There is no accepted method to test silicon or non-latex condoms.
"You end up with a balloon 3 feet (a metre) tall and a foot (30 cm) wide. They can really stretch an amazing amount," Metcalf said in a telephone interview.
The New York-based organization, which publishes the Consumer Reports magazine, also tested 16 other contraceptive choices.
"Condoms remain the only family planning and pregnancy prevention method that can help prevent sexually transmitted diseases, including HIV, which causes AIDS," the group, which has issued similar reports on condoms periodically since 1979, said in a statement.
"Condoms have improved since the mid-nineties because industry manufacturing standards have become more universally used and more effective," added Edward Kippel, who led the condom test project.
Intrauterine devices or IUDs have also become safer than in previous years, as have birth control pills, including so-called emergency contraception, the group said.
While abstinence has a 0 percent failure rate, doing nothing to prevent pregnancy has an 85 percent failure rate, the group found.
A U.S. government report published last month shows 98 percent of all U.S. women who have had sex have used birth control.