A top Aids research team may try to recruit about 1,000 at-risk men from Hong Kong and the mainland for clinical trials of an injection to prevent HIV infection.
If it goes ahead as planned next year, the project by the Aaron Diamond Aids Research Centre in New York will be the first HIV-prevention clinical trial in China.
The plan comes after the team, led by celebrated Taiwanese-American researcher Dr David Ho, used an antiretroviral drug dubbed GSK744 to protect laboratory monkeys from HIV for weeks.
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Clinical trials on men and women will start this week in the United States. For the mainland-Hong Kong trial, the team will seek men engaged in high-risk same-sex activity. But Professor Martin Markowitz, clinical director of the centre, which is an affiliate of Rockefeller University, said yesterday that the stigma surrounding gay men in China might pose a challenge.
"The biggest challenge is in recruitment and retention, that people identified to be at high risk are willing to come and commit."
Markowitz is "cautiously optimistic" the drug could be developed into an injection to protect humans from HIV for three months with one shot.
The effectiveness of oral pills already available for HIV prevention varied in different studies, mainly because people did not always take the drug daily as required for protection, he said.
Markowitz and two other team members arrived on Sunday for a two-day visit to explore the possibility of conducting trials in partnership with the University of Hong Kong. They also visited Shenzhen yesterday. In the final stage of their clinical trial from the end of next year to 2018, they are proposing to recruit 240 men in the US and 960 men in at least five locations in China.
They are aiming at the highest-risk group - men engaging in unprotected receptive anal intercourse with an untreated HIV-positive partner.
"The reason for us coming to China is the ever-growing epidemic among men who have sex with men. The infection rates are incredibly high," said Kathrine Meyers, the centre's China Aids Initiative programme director.
China's HIV infection rate was 0.058 per cent in 2011, but among men engaging in same-sex behaviour it was 6.3 per cent, according to the Ministry of Health.
In Hong Kong, 559 new cases of HIV infection were reported last year. Almost half of them were men having sex with men.
Andrew Chidgey, chief executive of non-governmental organisation Aids Concern Hong Kong, said: "I think there will be a lot of appetite to get involved, especially when we tell people that we're on the cusp of a scientific breakthrough."
Watch: How an expat lives in Hong Kong…with HIV