Tests carried out into China's first AIDS vaccine suggest the drug could prove effective at protecting people against the HIV virus, the Ministry of Science and Technology announced on Friday.

Initial clinical trials appear to show the vaccine can stimulate the immune system's response to HIV infection.

Zhang Wei, head of the pharmaceutical registration department of the State Food and Drug Administration, told a news briefing that "recipients of the vaccine appeared immune to the HIV-1 virus 15 days after the injection, indicating the vaccine worked well in stimulating immunity."

Kong Wei, the research team leader, said the initial results were "truly inspiring."

The test involved injecting 49 healthy men and women, aged 18-50, with the vaccine.

They also received HIV-1 specific cells that were DNA fragments of the virus and so were harmless.

"Quite a few of them, after taking both low and high dosages, showed a fairly positive response of immunity towards the virus," said Kong.

He added that the recipients' reaction improved as the dosage increased.

But Kong, a professor at Jilin University, declined to reveal more details, saying it was too early to draw a hasty conclusion.

Sang Guowei, director of the National Institute for the Control of Pharmaceutical and Biological Products, said "some of the recipients had (adverse) symptoms, but they were curable or ignorable."

The results marked the end of the first phase of clinical trials into the vaccine, which began in March last year in Nanning, capital of the Guangxi Zhuang Autonomous Region.

The trial volunteers were divided into eight groups and were each sampled five to 10 times. They showed no serious adverse reaction to the vaccine during the 180-day observation period.

"We strictly followed international practices during the trial, including the measurement of vaccine dosages," Kong said.

The scientists will now continue analysing the results before further clinical trials.

The ministry said the second trial phase would need more than 300 volunteers, including those from high-risk groups.

In the third phase, an even larger number of participants will be needed.

China started research of its own into an AIDS vaccine in 2003 and has more than 50 researchers involved in the work.

The country has about 650,000 HIV-affected people, including 75,000 AIDS patients, according to official estimates.

In the 10th Five-Year Plan (2001-05), more than 100 million yuan (US$12.5 million) was invested into AIDS-related research, according to Wang Hongguang, director of the China National Center for Biotechnology Development.

Two of the country's 16 key scientific research projects in the 11th Five-Year Plan (2006-10) focus on AIDS treatment and prevention.

Vice-Minister of Science and Technology, Liu Yanhua, said China has made several breakthroughs in AIDS-related studies.

Great progress has also been made in research into preventing mothers transmitting the HIV virus to their unborn children.

(China Daily August 19, 2006)