Doctors say they have shown for the first time that cheap generic Aids drugs are safe and effective.
Cheaper drugs offered the same benefits as more expensive drugs
Generic - non-branded - drugs are recommended by the World Health Organization to curb HIV in the developing world.
But critics say they have not been proven to be as good as more expensive brand drugs used in Western countries.
However University of Montpellier researchers, writing in the Lancet, say such concerns are unfounded.
Generic drugs are the same as brand-name products, but are dispensed under its generic chemical name.
They are cheaper, and can be sold on the market when the patent has expired on the branded version.
Professor Delaporte and colleagues looked at one of the most frequently prescribed treatments in Africa, a fixed-dose combination of three HIV drugs - nevirapine, stavudine and lamivudine - which are manufactured by Cipla in India.
They gave the drug combination to 60 HIV positive people in Cameroon and followed them for six months. The combination was found to be both safe and effective.
Overall, 80% of the people had no detectable virus in their blood, a measure of the drugs' success.
The researchers, led by Professor Eric Delaporte, wrote in the Lancet: "Although controlled trials including more patients and longer follow-up will be important, our results lend support to the use and funding of generic fixed-dose combinations as first-line treatment in developing countries." .
In addition to being cheaper, fixed-dose generic drugs are simpler to use, since patients need to take only two pills a day.
According to the World Health Organization, six million people in developing countries need anti-retroviral drugs, but less than 300,000 actually receive them.
In 2003 it launched a new strategy, called the "3x5" plan, to make these cheaper drugs more available and simplify treatment regimens for millions of HIV sufferers by the end of 2005, costing an estimated $5.5bn.
In an accompanying editorial in the Lancet Dr N Kumarasamy, chief medical officer of YRG Centre for AIDS Research and Education in India, said generic drugs would have a major role in tackling the HIV problem in resource-constrained settings.
But he thought some of the newer generic drugs might not be available.
"Because of patents by proprietary companies, newer antiretrovirals may not be manufactured by the generic companies, which might be a major obstacle to patients getting drugs in such settings," he said.
Another problem is the US does not fund Aids drugs which have not been approved by its Food and Drugs Administration.
The WHO set up a scheme to certify the quality of Aids drugs , but the US does not recognise this.
For generic drugs to be a cheap option, countries need to bulk-buy them. But if countries do not have the funding, they cannot bulk buy the drugs.
Keith Alcorn from National Aids Manual said: "It's sad really that we are still having to have arguments over studies of this sort to prove that generic products are just as effective as branded products.
"The reason we are having these arguments is because people whose main agenda is to protect US trade interests are continuing to cast doubt on the quality of generic products.
Lisa Power from the Terrence Higgins Trust said: "It's not surprising that generic drugs made by companies with high standards are comparable with branded drugs.
"The issue has been whether pirated drugs were a problem. If they are made in uninspected laboratories then they are not going to be of the same quality.
"Where a drug is out of its patent there is absolutely no reason not to use generics when they come from reputable manufacturers," she said.