News (Updated February 20,
2005)
[Home]
[Previous
news]
|
Fri Feb 18, 1:21 PM ET
|
PARIS (AFP) - France said it was suspending trials of two prototype vaccines against the AIDS virus as a precaution after an American volunteer suddenly fell ill with a neurological disorder.
The vaccines, codenamed Vac 16 and Vac 18, are part of an ambitious vaccine programme launched by the National Agency for AIDS (ANRS), and the suspension will put back work by a year, ANRS said.
The move was decided after a US volunteer in his forties needed hospitalization last December for myelitis, an inflammation of the spine that can cause problems with mobility and even lead to paralysis.
The volunteer, who has not been named, was not testing either of the French vaccines.
He had been injected with a test US vaccine, HVTN 42, which has now been withdrawn from trial by the American authorities, ANRS said.
Vac 16 and Vac 18 are affected, however, because both vaccines use HVTN 42 as part of their formula.
The volunteer had enrolled in another trial to test anti-HIV drugs, but it was unknown whether these drugs, when combined with the vaccine, had caused his problem, ANRS said.
AIDS vaccines try to prime the body's immune system to recognize the human immunodeficiency virus (HIV) which causes AIDS.
To do this, vaccine formulae are often a combination of several strategies that can borrow a molecule from another vaccine.
The search for a vaccine against the human immunodeficiency virus (HIV) is one of the most frustrating areas of AIDS research.
Only one vaccine has ever completed the long three-phase process of assessment for safety and effectiveness on humans, and the result was a disappointing failure.
|
Wed Feb 16,12:15 PM ET
|
DHAKA (AFP) - Japan's largest medical chain will build two new hospitals in Bangladesh to grab a share of the estimated 330 million dollars now spent annually on overseas health care, officials said.
Tokushukai Medical Corporation signed an agreement with Bangladesh's Grameen Bank in Tokyo last month to operate two 500-bed multi-speciality hospitals, one in the capital Dhaka and one in the port city of Chittagong, Grameen chairman Muhammad Yunus told AFP Wednesday.
"With an investment of 75 million dollars, this is going to be the largest private-health sector investment in Bangladesh," he said.
The Japanese chain operates 250 hospitals, nurse stations and clinics worldwide.
This is the second major investment in Bangladesh by a hospital company in the past month. In January, India-based Apollo Hospitals Group said it would invest 35 million dollars with a Bangladesh partner to build a 450-bed hospital in Dhaka.
Private clinics, nursing homes and small hospitals targeted at Bangladesh's small but growing middle class have proliferated since the early 1990s when the country firmly committed itself to a free market economy.
Most are small, however, and offer a limited range of services.
Although nearly half Bangladesh's 140 million population still lives on less than a dollar a day, the country's rich elite and growing middle class have sought medical help abroad because of concerns such as blood tainted with HIV.
Health Minister Khandoker Mosharraf Hossain appealed to doctors in December to ensure adequate blood screening to curb the spread of HIV/AIDS.
A Grameen-Tokushukai foundation will operate the two hospitals, which will be the largest Japanese investment in Bangladesh, officials of the country's investment promotion office said.
Grameen Bank, which began as a small pilot project by Yunus, is known worldwide for its pioneering work giving small loans to the poor to help them set up businesses.
The hospitals will have special programs to treat the poor, Yunus said. "For the poor, we will charge the minimum. Others will be charged less than what they pay abroad," he said.
Economist Moinul Islam, of Chittagong University, has said the growing private health care sector in Bangladesh would lead to worse services for the poor because doctors at existing hospitals would move to the new ones.
The government said in January it would provide funds to train 3,000 new doctors.
Wed Feb 16, 2005 05:01 PM ET
By Ben Hirschler
LONDON (Reuters) - The world's leading drugmakers are racing to be first to market with a new kind of pill that can block the AIDS virus before it enters human cells, experts said on Wednesday.
If successful, so-called CCR5 inhibitors should have fewer toxic side effects and offer hope to patients whose virus has developed resistance to existing antiretroviral medicines.
Pfizer Inc, with a product already in final Phase III tests, is a few months ahead, but both GlaxoSmithKline Plc and Schering-Plough Corp are on its tail.
The discovery of a potentially new virulent strain of HIV in a New York man at the weekend has highlighted the need for fresh pharmaceutical weaponry in the fight against AIDS.
Dr Graeme Moyle, an HIV expert at the Chelsea and Westminster Hospital in London, said he expected the first CCR5 drugs to reach the market in 2007 or 2008.
"We need these drugs," Moyle told reporters. "We have downsides with the medications we have at present in terms of toxicity, in terms of patient adherence and in terms of the management of virus resistance, which makes the need for new drug classes absolutely critical."
Drug resistance is a growing problem in both the United States and Europe, although Moyle cautioned against extrapolating from the one-off case in New York.
Scientists are still studying virus isolated from the man in his 40s, which appears to not only resist most drugs on the market but to damage the immune system more quickly than normal.
NECK-AND-NECK IN TESTS
Moyle said CCR5 pills from all three companies showed similar effectiveness in early tests and were as good as the best existing drugs in reducing levels of virus in the blood.
More information on their performance is expected at the 12th Conference on Retroviruses and Opportunistic Infections in Boston from Feb. 22 to 25.
"What we have is three demonstrably active drugs that are all working at about the same magnitude of effect," he said.
Industry analysts estimate that a successful CCR5 drug should generate sales of $500-700 million a year.
GSK aims to file its product for approval in 2007 while Schering-Plough hopes to start Phase III testing around the middle of this year, company officials said.
Most existing HIV drugs work inside the body's immune cells, after the virus has infected -- and they can cause anemia, nerve pain, diarrhea, fat wasting and even organ damage.
That has led researchers to study other approaches.
Switzerland's Roche Holding AG and U.S. biotech group Trimeris Inc launched the first drug to stop HIV from entering healthy immune cells in 2003.
But Fuzeon is expensive, must be injected twice daily and sales -- $135 million in 2004 -- have been disappointing.
The new drugs work differently and can be given as a tablet.
NATURAL IMMUNITY
The idea for the drugs -- which lock a cellular doorway, or co-receptor, called CCR5 -- came from the observation that people with mutated CCR5 can resist HIV infection, even after exposure to numerous high-risk sexual partners. Just under 2 percent of Caucasians carry the mutation.
"There is an accident of nature that has proved the hypothesis, because patients with CCR5 mutations don't get HIV," GSK's research head Tachi Yamada told Reuters in a recent interview.
"So not only can it potentially prevent the propagation of the virus, and therefore treat the infection, but it could also potentially be prophylactic."
Still, CCR5 inhibition will not be a panacea since the virus can switch and use alternative routes to enter cells, including another co-receptor called CXCR4, though this is less common.
Canada's AnorMED Inc has an experimental CXCR4 inhibitor in early-stage clinical development.
Tue Feb 15, 2005 04:05 PM ET
CHICAGO (Reuters) - Sudden jumps of HIV levels in patients taking drugs for the
AIDS-causing infection are harmless blips and do not mean the treatment against
the virus is losing its punch, a report said on Tuesday.
"These results should provide relief to hundreds of thousands of HIV-positive patients in the United States currently taking drug therapy, called highly active anti-retroviral therapy ... and reassure them that their medications have not failed," said Robert Siliciano, a doctor at The Johns Hopkins University School of Medicine who was involved in the study.
The study from the Baltimore institution published in this week's Journal of the American Medical Association found that the blips are mathematical variations stemming from the test used to gauge the amount of virus in the body.
The researchers said they analyzed blood samples from 10 HIV-positive patients, taking samples every two to three days for three months.
A statistical analysis found that blips occurred in nine of the 10 patients and typically lasted less than three days. The tests found no mutations taking place, the study said.
"The lack of any consistency among the tests performed on blood samples confirms that there is no danger from these blips in viral load," said the study's lead author, Richard Nettles.
"These blips can be attributed to random statistical artifact inherent in measurements of very low amounts of virus," he added.
The authors also said the blips do not warrant changes in the course of drugs being taken by patients.
Story from BBC NEWS
|
Fri Feb 18, 3:30 PM ET
|
By PAUL RECER, AP Science Writer
WASHINGTON - Detecting illegal drug use may one
day become as simple as testing spit on a sponge. Researchers on Thursday said
techniques now being developed for analyzing saliva may in the future replace
many of the blood and urine tests that now are used to detect drug abuse and
disease.
Some law enforcement agencies in Europe already test drugged drivers using
saliva and the technique is gaining acceptance in the U.S., said Edward Cone, a
Maryland researcher developing equipment for using oral fluids to screen for
drug abuse.
"There are a lot of advantages to using oral fluid or spit," he
said Thursday at a news conference of the national meeting of the American
Association for the Advancement of Science. "It is easily accessible,
noninvasive and not embarrassing. You don't have to greet an employee with a
urine cup."
Most people produce more than a quart of saliva a day. Researchers have found
the oral fluids accurately mirror the proteins that are found in blood and
urine. This means that simple spit could provide a diagnostic window on the body
in tests not requiring a needle or the embarrassing collection of urine.
Cone said experiments have already shown that spit can be even more reliable
than urine tests for drug use screening.
"Drug users have learned how to beat the urine test in a variety of
ways," said Cone, an organic chemist who heads up firm near Annapolis, Md.
"We haven't found any way to beat the oral fluids test."
At the news conference, researchers said saliva tests also are being
developed to detect virus and bacterial infections, and there is the possibility
that some cancer tests one day will be based on spit chemistry.
"It has been known for decades that what is in the blood is also present
in the saliva," said David Wong, a researcher at the University of
California, Los Angeles, Jonsson Cancer Center. He said the National Institutes
of Health are now financing studies to develop oral fluids tests that could
detect infection and some types of cancer.
First, though, Wong said, science is studying saliva from healthy people. The
oral fluid is a complex collection of many proteins, and researchers want to
develop an accurate profile of the compounds present in the mouths of normal
patients.
Then, he said, researchers will search for the chemical differences that may
reflect disease.
"We'll look in the oral fluids for the chemical signature of a disease
process," said Wong.
A technique is now being refined, he said, that can detect the telltale
proteins produced by oral cancer.
Daniel Malamud of the University of Pennsylvania said his research team has
developed a sponge-tipped wand that can collect saliva from a patient and then
transfer it to an analyzer that can identify DNA, antibodies and other compounds
linked to virus and bacterial infections.
He said laboratory experiments show the technique can detect evidence of
infection from the HIV virus and from a bacteria similar to anthrax.
Eventually, he said, science will learn how use saliva to find evidence for
any type of virus or bacteria present in the bloodstream.
A University of California team found an "impotent" version of HIV, with the disease-causing parts of it removed, tracked down cancer cells in mice.
The next step would be to insert a gene into the virus that would kill the cancer upon contact.
The team told Nature Medicine more safety studies were needed before such a method could be tested in humans.
Gene therapy
The mice they studied had a form of skin cancer, called melanoma, that had spread to the lungs.
In the laboratory, the scientists took HIV and removed the parts of the virus that causes disease.
|
The virus travelled through the bloodstream and homed straight to
the cancer cells Researcher Dr Irvin Chen |
They then stripped off the virus' outer coat and redressed it with the outer suit of another virus.
By doing this, the researchers had changed the target of the virus.
HIV normally infects immune cells called T cells. The new outer coat instead directed HIV to hunt down molecules present on cancer cells, called P-glycoproteins.
The scientists also added a substance to the virus that would make it visibly glow when looked at with a special camera so they could track where it travelled once injected into the mice.
Researcher Dr Irvin Chen, from UCLA's Aids Institute, said: "The virus travelled through the bloodstream and homed straight to the cancer cells in the lungs, where the melanoma had migrated.
"Gene therapy has been hampered by the lack of a good carrier.
"Our approach proves that it is possible to develop an effective carrier and reprogram it to target specific cells in the body."
Beating cancer's spread
His team is planning to see whether the virus could carry a therapeutic gene to the precise location of the cancer.
As well as controlling cancer, they hope this technique might be useful for treating genetic diseases.
Dr Georges Vassaux, from Cancer Research UK's clinical centre at Barts and The London, said: "This is the first time that a vector - or delivery system - for gene therapy has targeted a tumour in such a specific manner.
"This means the technique could be used to use gene therapy in cases where cancer has spread around the body.
"So far gene therapy has been successfully used only on tumours that are confined to their original location."
He said there had been concerns that such methods might cause leukaemia in normal cells.
"As the team has managed to target the therapy to cancer cells, it
looks as though a hazard associated with the use of integrative viruses may
have been overcome," he said.