But patients with limited means, including those who are unable to earn because of workplace discrimination, find it difficult to remain stoic because they have no access to treatment, he warned.

In response, Cai said the less well-off can still receive free care, but he compared the basic treatment with taking a bus, while the pilot program is like using a taxi instead.

There are other concerns, too. Meng Lin, a Beijing-based patient, was concerned that the project might herald an end to free treatment. He accused Cai of selling government-funded TDF for profit on Sina Weibo, a popular Chinese micro blog. The allegation has not been substantiated, but it drew a huge amount of attention, particularly among people with AIDS or HIV.

Cai said that the TDF used in the pilot program and endorsed by the authorities, came from independent sources outside the national drug-supply system. "The government helped us to purchase TDF at a bargain price after negotiations with pharmaceutical companies," he said. The drug cost roughly 180 yuan per patient per month, compared with the market price of 1,400 yuan.

"With willing and economically capable patients shouldering some of the cost, the money saved could help to gradually expand the provision of better drug regimens and services among the poor," Cai noted. However, he pointed out that the basic facets of the service package, including the use of first-line drugs, the viral load and CD4 tests, are still funded by the government, "Participants are just paying for the additional benefits," he said.

"We are still testing the model, which will cap the number of total participants at 200 spread across two sites in Wuhan and Xiangfan," he added.

Wu Zunyou said the model of patient co-payment AIDS treatment has already been adopted by many countries and that so far "the pilot's been quite positive".

For other chronic diseases such as diabetes, hepatitis B and hypertension, a number of health insurance policies require patients to pay for certain parts of the treatment, said Xiao Dong, who heads a civil organization committed to controlling HIV/AIDS in Beijing. "Why shouldn't AIDS patients (pay), then?" he asked.

At the 2012 national AIDS control conference, held in February, local health authorities were encouraged to research and explore ways to integrate AIDS treatment in the coverage provided by health insurance policies, coupled with a special assistance program.

Zhao agreed with the move, saying that the inclusion of AIDS treatments in the existing health insurance policies would be of huge benefit. "And our pilot would help that move because of the cost calculation and real experience," she said.

However, Wu said that the model won't be expanded to other parts of China anytime soon, pointing out that medical and public opinion will have to be gauged.

Contact the reporter at shanjuan@chinadaily.com.cn