Japanese and Thai researchers said Tuesday they have successfully inoculated monkeys against SIV, the simian version of the human immunodeficiency virus.

The researchers tested two types of anti-AIDs vaccines on three monkeys and plan to conduct clinical tests on people infected with HIV and people with AIDS in Thailand as early as next year.

It will be the first time for a Japanese-developed AIDS vaccine to undergo clinical trials.

The Thai public health institute and the research group, led by Mitsuo Honda at the National Institute of Infectious Diseases, developed the two vaccines by splicing HIV genes with tuberculosis vaccine BCG and smallpox vaccine.

In one of the experiments, the researchers gave the three monkeys both of the combined vaccines before infecting them with SIV.

After several months, two of the monkeys exhibited no detectable levels of the virus. The third monkey showed extremely low levels but did not develop AIDS symptoms.

The vaccines are aimed at boosting the immune system to fight HIV and are free of risk, according to the researchers.

In other experiments, in which monkeys were given no vaccine or only one of the vaccines, the virus levels could not be suppressed, the researchers said.