Thursday, September 24, 2009

A world first: Vaccine helps prevent HIV infection

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ANGKOK -For the first time, an experimental vaccine has prevented infection with the AIDS virus, a watershed event in the deadly epidemic and a surprising result. Recent failures led many scientists to think such a vaccine might never be possible.
The World Health Organization and the U.N. agency UNAIDS said the results "instilled new hope" in the field of HIV vaccine research.
The vaccine — a combination of two previously unsuccessful vaccines — cut the risk of becoming infected with HIV by more than 31 percent in the world's largest AIDS vaccine trial of more than 16,000 volunteers in Thailand, researchers announced Thursday in Bangkok.
Even though the benefit is modest, "it's the first evidence that we could have a safe and effective preventive vaccine," Col. Jerome Kim told The Associated Press. He helped lead the study for the U.S. Army, which sponsored it with the National Institute of Allergy and Infectious Diseases.
The institute's director, Dr. Anthony Fauci, warned that this is "not the end of the road," but said he was surprised and very pleased by the outcome.
"It gives me cautious optimism about the possibility of improving this result" and developing a more effective AIDS vaccine, Fauci said. "This is something that we can do."
The Thailand Ministry of Public Health conducted the study, which used strains of HIV common in Thailand. Whether such a vaccine would work against other strains in the U.S., Africa or elsewhere in the world is unknown, scientists stressed.
Even a marginally helpful vaccine could have a big impact. Every day, 7,500 people worldwide are newly infected with HIV; 2 million died of AIDS in 2007, UNAIDS estimates.
"Today marks a historic milestone," said Mitchell Warren, executive director of the AIDS Vaccine Advocacy Coalition, an international group that has worked toward developing a vaccine.
"It will take time and resources to fully analyze and understand the data, but there is little doubt that this finding will energize and redirect the AIDS vaccine field," he said in a statement.
The study tested the two-vaccine combination in a "prime-boost" approach, in which the first one primes the immune system to attack HIV and the second one strengthens the response.
They are ALVAC, from Sanofi Pasteur, the vaccine division of French drugmaker Sanofi-Aventis; and AIDSVAX, originally developed by VaxGen Inc. and now held by Global Solutions for Infectious Diseases, a nonprofit founded by some former VaxGen employees.
ALVAC uses canarypox, a bird virus altered so it can't cause human disease, to ferry synthetic versions of three HIV genes into the body. AIDSVAX contains a genetically engineered version of a protein on HIV's surface. The vaccines are not made from whole virus — dead or alive — and cannot cause HIV.
Neither vaccine in the study prevented HIV infection when tested individually in earlier trials, and dozens of scientists had called the new one futile when it began in 2003.
"I really didn't have high hopes at all that we would see a positive result," Fauci confessed.
The results proved the skeptics wrong.
"The combination is stronger than each of the individual members," said the Army's Kim, a physician who manages the Army's HIV vaccine program.
The study tested the combo in HIV-negative Thai men and women aged 18 to 30 at average risk of becoming infected. Half received four "priming" doses of ALVAC and two "boost" doses of AIDSVAX over six months. The others received dummy shots. No one knew who got what until the study ended.
Thanad Yomha, a 33-year-old electrician from southeastern Thailand, said he didn't expect anything in return for volunteering for the project.
"I did this for others," Thanad said. "It's for the next generation."
All were given condoms, counseling and treatment for any sexually transmitted infections, and were tested every six months for HIV. Any who became infected were given free treatment with antiviral medicines.
Participants were followed for three years after vaccination ended.
The results: New infections occurred in 51 of the 8,197 given vaccine and in 74 of the 8,198 who received dummy shots. That worked out to a 31 percent lower risk of infection for the vaccine group. Two of the infected participants who received the placebo died.
The vaccine had no effect on levels of HIV in the blood for those who did become infected. That had been another goal of the study — seeing whether the vaccine could limit damage to the immune system and help keep infected people from developing full-blown AIDS.
That result is "one of the most important and intriguing findings of this trial," Fauci said. It suggests that the signs scientists have been using to gauge whether a vaccine was actually giving protection may not be valid.
"It is conceivable that we haven't even identified yet" what really shows immunity, which is both "important and humbling" after decades of vaccine research, Fauci said.
Details of the $105 million study will be given at a vaccine conference in Paris in October.
This is the third big vaccine trial since 1983, when HIV was identified as the cause of AIDS. In 2007, Merck & Co. stopped a study of its experimental vaccine after seeing it did not prevent HIV infection. Later analysis suggested the vaccine might even raise the risk of infection in certain men. The vaccine itself did not cause infection.
In 2003, AIDSVAX flunked two large trials — the first late-stage tests of any AIDS vaccine at the time.
It is unclear whether vaccine makers will seek to license the two-vaccine combo in Thailand. Before the trial began, the U.S. Food and Drug Administration said other studies would be needed before the vaccine could be considered for U.S. licensing.
"This is a world first which proves that vaccine development is possible," said Dr. Supachai Rerks-Ngarm, the Thai Health Ministry official who oversaw the trial. "But this is not to the level where we can license or manufacture the vaccine yet."
Mass-producing the vaccine, plus how to proceed with future studies, will be discussed among the governments, study sponsors and companies involved in the trial, Kim said. Scientists want to know how long protection will last, whether booster shots will be needed, and whether the vaccine helps prevent infection in gay men and injection drug users, since it was tested mostly in heterosexuals in the Thai trial.
The study was done in Thailand because U.S. Army scientists did pivotal research in that country when the AIDS epidemic emerged there, isolating virus strains and providing genetic information on them to vaccine makers. The Thai government also strongly supported the idea of doing the study.

ULFA victim inspires NFDC film

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welve years after members of the United Liberation Front of Asom (ULFA) abducted and killed social worker Sanjoy Ghosh, the National Film Development Corporation is set to release a bilingual film inspired by his activism and disappearance.

The film, Ekhon Nedekha Nodir Xipaare (As the River Flows) is expected to rake up a storm. For Ghosh – as a boatman who ferried him along with his four ULFA captors on July 4, 1997 testified in court later – was “punished for exposing the unholy nexus between contractors, militants and government officials in Majuli.

The boatman also said Ghosh was killed the day he was abducted. The prime accused, ULFA leader Mridul Hazarika alias Bhaskar Barua, was killed in an encounter on July 31, 2006.

One of the largest freshwater islands in the world, Majuli is the nerve centre of Vaishnavite culture in Assam. It is sited in the river Brahmaputra 350 km east of Guwahati.

But the film’s director, Bidyut Kotoky, insists the feature film in Hindi and Assamese is not based on the ULFA victim’s life. “This is a story of a Mumbai-based journalist named Abhijit who comes in search of a social worker Sridhar six years after he disappeared,” he said.

The backdrop of the film, though, is Majuli, where Ghosh had worked on low-cost anti-erosion ideas that did not allegedly factor in the “revolutionary donations” to the ULFA unlike expensive government projects.

Ghosh’s body was never found. Sridhar too has a similar fate, and the film draws on an Indian law that states “a person cannot be declared dead for seven years until his body his found”. It claims to be a work of fiction, but at the same time the promos say any reference to any person dead or alive is not co-incidental…it is intentional”.

Sanjay Suri plays the lead role of Abhijit, who too is abducted by militants one day. The female lead as Sridhar’s widow is played by model-turned-actor Bidita Bag.

New outfit keeping militancy alive in NC Hills?

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here’s no business like extortion-driven militancy in the Northeast. The reported birth of a new outfit in the North Cachar Hills district of Assam, coinciding with the process of surrender of a dreaded tribal outfit, makes this apparent.

Earlier this month, 373 of some 450 members of Dima Halam Daogah (Jewel) outfit deposited their weapons and moved to designated camps. It raised hopes of peace returning to ethnically volatile NC Hills, but the reported emergence of another tribal outfit – Halam National Liberation Front (HNLF) – has somewhat dented the peace process.

The DHD (J) is partial to the Dimasas, the largest of 12 major ethnic groups in NC Hills. The HNLF represents the Hrangkhols, who number some 4,000 in and around district headquarters Haflong.

According to Intelligence officials, the National Socialist Council of Nagaland (Isak-Muivah) has been propping up HNLF as a bulwark against the DHD (J) and its parent group DHD (Nunisa), which had surrendered a few years back.

Both DHD factions are opposed to the Naga militants’ presence in NC Hills and their perception of a Dimasa homeland includes parts of Nagaland. The NSCN (I-M), on the other hand, wants a large chunk of NC Hills to be included in its map of Greater Nagaland.

“The NSCN (I-M) had inducted 21 Hrankhol youths and trained them in its Hebron Camp near Dimapur (in Nagaland) to ensure a share of the extortion and arms dealing market in NC Hills,” reports quoting Special Branch and a former Assam police chief said.

However, NC Hills superintendent of police Anurag Tankha said he was not in the know of any new outfit floated by the Hrangkhols. “We would certainly be looking into these reports,” he told Hindustan Times from Haflong.

Johnny Paithong, spokesman of an apex body of Hrangkhols, too denied NSCN (I-M) links with youths of the community. “The Hrangkhols are a peaceful community, but at the same time we are committed to protecting our interests,” he said.

Non-Dimasas, notably, have been at the receiving end in NC Hills since 2003. For several months that year, Dimasas clashed with Hmars in certain pockets. Attacks and counter-attacks by Dimasa and Karbi militants on villages of each other’s communities followed. The latest ethnic violence – between March and August this year – saw the Dimasas and Zeme Nagas pitted against each other, claiming over 50 lives.