News (Updated
July 20, 2008)
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Fri Jul 18, 6:27 AM ET
US scientists have scrapped plans for a large trial of a HIV vaccine due to concerns about its effectiveness, the government's medical research agency said.
The decision on the government-developed vaccine comes less than a year after a trial for a similar vaccine from the pharmaceutical company Merck failed -- marking another setback in the decades-long struggle to develop a successful vaccine to fight the scourge of AIDS.
The National Institute of Allergy and Infectious Diseases (NIAID), part of the government's National Institutes of Health, said after consulting scientists and advocacy groups it "has determined that it will not conduct the HIV vaccine study known as PAVE 100."
"However, NIAID believes the vaccine developed by its Vaccine Research Center (VRC) is scientifically intriguing and sufficiently different from previously tested HIV vaccines to consider testing it in a smaller, more focused clinical study," the agency said in a statement issued on Thursday.
The smaller-scale study would examine if the vaccine regimen lowers the amount of HIV in the blood of vaccinated individuals, the agency said.
The trial, which was to involve 8,500 volunteers in the United States, South America, the Caribbean and Africa, had been viewed as a test of a promising vaccine that uses virus strains from around the world to prompt immunity.
The failure of Merck's vaccine influenced the decision to cancel the planned trial of the government's PAVE vaccine, US media reported on Friday.
The Merck vaccine in tests failed to prevent HIV infection or reduce the amount of HIV in the blood of patients, the government agency said.
Results also indicated that it may have even increased the risk of infection for some patients.
The official who canceled the PAVE trial, Doctor Anthony Fauci, director of the NIAID, said a large trial was not justified until fundamental questions could be answered about how the vaccine operates.
"Show me that the vaccine works by lowering the amount of HIV in the blood," Fauci was quoted as saying by the New York Times.
"Then we will move to a larger trial that will document the link with a particular immune response," he said. Until then, "doing a large trial is not justified."
The agency said it would continue to strive to find an AIDS vaccine, an effort that began more than 20 years ago.
"An HIV vaccine continues to be our best hope for ending the HIV pandemic," it said.
"NIAID is committed to supporting the basic research and vaccine discovery needed to design promising vaccine candidates and testing those candidates when appropriate."
Thu Jul 17, 1:15 PM ET
A gene found only in people of African ancestry which evolved to prevent malaria infection now increases the odds of contracting AIDS by up to 40 percent, a new study has found.
The gene does, however, seem to protect against the progression of the disease, allowing those carrying it to live about two years longer.
Around 90 percent of people in Africa carry this genetic variant and it may be responsible for 11 percent of the infections there, the study published Wednesday in Cell Host & Microbe found.
"After thousands of years of adaptation, this Duffy variant rose to high frequency because it helped protect against malaria," said co-author Matthew Dolan of the Wilford Hall United States Air Force Medical Center.
"Now, with another global pandemic on the scene, this same variant renders people more susceptible to HIV."
About 68 percent of people infected with HIV live in Sub-Saharan Africa, according to the United Nations.
The US and British researchers who authored the study said sexual behavior and other social factors do not fully explain large discrepancies in HIV prevalence.
"It's well-known that individuals vary in their susceptibility to HIV and that after infection occurs, the disease progresses at variable rates," said co-author Sunil Ahuja of the South Texas Veterans Health Care System.
"The mystery of variable infection and progression was originally thought to be mainly the result of viral characteristics, but in recent years it has become evident that there is a strong host genetic component."
The gene in question, the Duffy Antigen Receptor for Chemokines (DARC), encodes a protein found mainly at the surface of red blood cells.
Earlier studies have shown that HIV can bind to red blood cells through this receptor. The receptor has also been found to bind a wide array of inflammatory molecules, including one which is highly effective in suppressing replication of HIV.
The researchers studied nearly 3,500 people in the US Air Force, including more than 1,200 who are HIV positive, who have been followed for nearly 22 years.
This allowed them to rule out difference in economic status, access to health care and other factors which would generally confound a genetic effect. They found that the prevalence of the variant in African Americans was greater amongst those with HIV than in those without.
Researchers in Canada, meanwhile, have isolated two genes which may prevent people from contracting HIV or at least slow the rate at which they develop AIDS, a second study published Wednesday.
The genes were isolated by comparing the genetic profiles of people in their first year of HIV infection with those who managed to resist infection despite repeated exposure to the virus.
The "good" versions of the two genes were present in 12.2 percent of those who resisted infection compared with only 2.7 of patients in primary HIV infection.
Researchers are not yet sure how this protection works.
One of the gene codes for a receptor on the surface of the immune system's natural killer cells which destroy infected cells in the body.
The other codes for a protein which binds the first gene and dampens the natural killer cell activity.
The most likely explanation is that HIV prevents the protein that dampens the killer cell activity from being expressed, allowing the killer cells to destroy cells infected with HIV.
Since this can happen very soon after the initial infection, people carrying those genes may be able to more efficiently destroy infected cells and lower their chances of developing AIDS.
"More research is needed to determine the exact mechanism behind the protection we have observed, but these findings have revealed a promising avenue," said co-author Nicole Bernard of the Research Institute of the McGill University Health Centre.
"In the future, our findings could be used to somehow 'boost' the innate immune system and thus fight the virus as soon as it enters the body."
The study was published Wednesday in the journal AIDS.
Thu Jul 17, 10:40 AM ET
Scientists have isolated two genes which may prevent people from contracting HIV or at least slow the rate at which they develop AIDS, a new study has found.
The genes were isolated by comparing the genetic profiles of people in their first year of HIV infection with those who managed to resist infection despite repeated exposure to the virus.
The "good" versions of the two genes were present in 12.2 percent of those who resisted infection compared with only 2.7 of patients in primary HIV infection.
Researchers are not yet sure how this protection works.
One of the genes codes for a receptor on the surface of the immune system's natural killer cells which destroy infected cells in the body.
The other codes for a protein which binds the first gene and dampens the natural killer cell activity.
The most likely explanation is that HIV prevents the protein that dampens the killer cell activity from being expressed, allowing the killer cells to destroy cells infected with HIV.
Since this can happen very soon after the initial infection, people carrying those genes may be able to more efficiently destroy infected cells and lower their chances of developing AIDS.
"More research is needed to determine the exact mechanism behind the protection we have observed, but these findings have revealed a promising avenue," said co-author Nicole Bernard of the Research Institute of the McGill University Health Centre in Montreal.
"In the future, our findings could be used to somehow 'boost' the innate immune system and thus fight the virus as soon as it enters the body."
The study was published Wednesday in the journal AIDS.
By Deepa Seetharaman
NEW YORK (Reuters) - Swiss pharmaceutical company Roche Holding AG will suspend its HIV research because none of its pending medicines represent significant improvement over existing drugs, a company spokeswoman said on Friday.
"Research scientists currently working in HIV will be reassigned to other activities," Linda Dyson, a spokeswoman in Roche's U.S. office in New Jersey, said in an e-mail.
Dyson confirmed an e-mail sent on Wednesday to some activists informing them of the decision. In that e-mail, the company said it "decided to refocus our resources within virology on diseases in which we can deliver substantial improvements over existing medications."
Dyson declined to specify how much Roche has been investing in HIV research.
She also said she could not specify how many employees worked in the HIV research division. Roche employs 5,000 people in the U.S. and 3,000 in its New Jersey office.
The company said in the e-mail to some activists that it initially had been excited about the potential for drugs in pre-clinical testing, but it has "concluded that none would provide a true incremental benefit for patients compared to medicines currently on the market."
Roche said it would continue to support its molecular diagnostic tests and drugs already on the market, including the fusion-inhibitor Fuzeon.
Roche has partnered with Morrisville, North Carolina-based biotech Trimeris Inc to sell Fuzeon, which netted $266.8 million in sales last year.
But the drug struggled because of its cost -- $25,000 for a year's supply -- exceeding the cost of other HIV drugs on the market, said Peter Staley, founder of AIDSmeds.com, which tracks HIV- related news.
The launch of new drugs and an uptick in HIV cases is set to make AIDS medicine a $10.6 billion market by 2015, according to a study published last year by independent market research firm Datamonitor.
More than 20 separate HIV drugs are available, with several combination pills also available. None can cure the fatal disease, which infects an estimated 33 million people globally and which has killed 25 million.
The drugs fall into various classes, each of which interferes with the replication of the virus at a different stage. The human immunodeficiency virus hijacks immune system cells, forcing them to create copies of itself.
Activists said they would not mourn the withdrawal of Roche from the field.
"They're not beloved in the AIDS community," said James Love, Director of Knowledge Ecology International, an advocacy group that focuses on access to medication.
"They are criticized a lot by people in the AIDS field because they are the least willing to give discounts on their AIDS drugs."
The decision reflects "the lack of productivity among the groups that they have working in this area," he said, adding that "a lot of the big pharma companies haven't been very impressive in terms of their big internal pipeline."
Staley said Roche has never come up with an AIDS drug that has sold really well.
"Roche is a big company and they've been trying to get this right for many, many years." Staley said.
"It is disappointing that there is one less big pharmaceutical company in this field. I don't think it's a sign of a serious problem in pharma's commitment."
(Editing by Maggie Fox and Andre Grenon)
BEIJING, July 18 (Xinhua) -- China earnestly fulfills its commitments to the WTO and implements a data protection system for drugs, said a white paper published on Friday by the Information Office of the State Council.
The white paper, titled Status Quo of Drug Supervision in China, said to prevent generic drugs from freely using the research and development data of new drugs, and therefore hindering the motivation for inventing new drugs, China earnestly fulfills its commitments to the WTO and implements a data protection system for drugs.
The Regulations for the Implementation of the Drug Administration Law of the People's Republic of China amended in 2002 stipulates that undisclosed data of drug studies and others which are independently acquired and submitted by drug manufacturers or sellers who eventually obtained production or marketing approval for the drugs in question which contain new chemical entities enjoy a six-year protection period, the paper said.
Furthermore, the state implements special evaluation and approval procedures to encourage the invention of new drugs and the development and research of new drugs for treating difficult, complicated and severe diseases, according to the paper.
It said that the special procedures are applicable to the following new drugs: active ingredients which are extracted from plants, animals, minerals and other materials and have not been marketed in China, and preparations containing these ingredients; newly discovered medicinal materials and their preparations; drugs made of chemical materials which have not been marketed domestically or internationally and their preparations and biologicals; new drugs with obvious clinical advantages for treating AIDS, malignant tumors and rare diseases; and new drugs for diseases without effective treatment.
Editor: Du Guodong