This could not only transform the care of patients in much of the world but also ignite a counterattack by major pharmaceutical companies and richer countries.

Chinese and Indian drugmakers have taken over much of the global trade in medicines and now manufacture more than 80 per cent of the active ingredients in drugs sold worldwide. But they had never been able to copy the complex and expensive biotech medicines increasingly used to treat cancer, diabetes and other diseases in rich nations like the United States until now.

These generic drug companies say they are on the verge of selling cheaper copies of such huge sellers as Herceptin for breast cancer, Avastin for colon cancer, Rituxan for non-Hodgkin's lymphoma and Enbrel for rheumatoid arthritis. Their entry into the market in the next year made possible by hundreds of millions of dollars invested in biotechnology plants could not only transform the care of patients in much of the world but also ignite a counterattack by major pharmaceutical companies and diplomats from richer countries.

Already, the Obama administration has been trying to stop an effort by poorer nations to strike a new international bargain that would allow them to get around patent rights and import cheaper Indian and Chinese knock-off drugs for cancer and other diseases, as they did to fight AIDS. The debate turns on whether diseases like cancer can be characterised as emergencies, or “epidemics.”

Rich nations and the pharmaceutical industry agreed 10 years ago to give up patent rights and the profits that come with them in the face of an AIDS pandemic that threatened to depopulate much of Africa, but they see deaths from cancer, diabetes and other non-communicable diseases as less dire and, in some cases, the inevitable consequence of better and longer living.

The debate has intensified in recent weeks, before world leaders gather at the United Nations on Monday and Tuesday to confront surging deaths from non-communicable diseases, which cause two-thirds of all deaths. It is only the second global health issue that the U.N. General Assembly has deemed urgent enough to call a meeting to discuss.

Participants in the negotiations, which include nongovernmental organisations, described the Obama administration's position on the issue and provided e-mails from European diplomats that laid out the American stance, which has been adopted in the agreement's working draft.

Although the draft agreement for this week's meeting at the United Nations offers no support for poor nations seeking freer patent rules to fight cancer and other non-communicable diseases, their advocates have vowed to continue fighting to loosen those restrictions not only this week in New York but in continuing international trade negotiations around the world as well.

U.S. officials repeatedly declined to explain the U.S. position, though Mark Toner, a State Department spokesman, said on Friday: “Regardless of what you call it, this is clearly such a pressing challenge globally that world leaders are gathering in New York next week to discuss ways to confront this threat.” The U.S. government has a long history of pushing for strong patent protections in international trade and other agreements to protect important domestic industries like pharmaceuticals and ensure continued incentives for further inventions.

The new biotech copycats are likely to stir sharp debate among advocates for the poor. Already, some contend that the billions spent to treat AIDS have crowded out cheap and simple solutions to other afflictions of poverty, such as childhood diarrhoea.

The new biotech copycats will be less expensive than the originals, but they will never be cheap. It is unlikely that many African nations will be able to afford such a costly medicine for breast cancer, when far cheaper ones for colon and testicular cancer are lacking.

Dr. Yusuf K. Hamied, chairman of the Indian drug giant Cipla Ltd., electrified the global health community a decade ago when he said he could produce cocktails of AIDS medicines for $1 per day — a fraction of the price charged by branded pharmaceutical companies. That price has since fallen to 20 cents per day, and more than six million people in the developing world now receive treatment, up from little more than 2,000 in 2001.

Dr. Hamied said in a telephone interview last week that he and a Chinese partner, BioMab, had together invested $165 million to build plants in India and China to produce at least a dozen biotech medicines. Other Indian companies have also built such plants. Since these medicines are made with genetically engineered bacteria, they must be tested extensively in patients before sale.

Once those tests are complete, Dr. Hamied promised to sell the drugs at a third of their usual prices, which typically cost tens of thousands of dollars for a course of treatment.

“And once we recover our costs, our prices will fall further,” he said. “A lot further.”

Dr. Peter Piot, a former director of UNAIDS, the U.N. AIDS agency, said the parallels between the current dilemma over cancer drugs and the one 10 years ago over AIDS medicines were striking. “Without a major reduction in the prices of the essential oncology drugs, there's no way we can really improve survival from cancer,” said Dr. Piot, currently the director of the London School of Hygiene and Tropical Medicine.

But he also said he was more cautious about the promise of generics this time, because biotech medicines were not easy to copy. “I believe these medicines will make a huge difference, but I would like to see the evidence that the quality is good before giving it to my patients or taking it myself,” he said.

Patents generally provide inventors rights to 20 years of exclusive sales, but international law allows countries to force companies to share those rights with competitors under a variety of circumstances, including to protect public health.

Even then, countries are generally not allowed to export the products that result from forced patent sharing except under dire circumstances.

But the only way poor countries can get drugs that result from shared patent rights is if another country exports those medicines to them under emergency exceptions.

In retrospect, the battle 10 years ago over AIDS medicines was a small skirmish compared with the one likely to erupt over cancer, diabetes and heart medicines. The AIDS drug market was never a major money-maker for global drug giants, while cancer and diabetes drugs are central to the companies' very survival.

Roche Holding Ltd. earns $19 billion annually, or half its annual drug sales, selling Rituxan, Avastin and Herceptin. And sales of Herceptin have been rising faster in the developing world than in richer nations making the developing world a crucial market. For middle-income countries straining to provide the best medicine possible, the new copycat biotechs will almost certainly be warmly received.

Mexico alone spends about $120 million buying Herceptin to treat women with breast cancer, which is nearly one-half of one per cent of all government spending on health care, said Dr. Alejandro Mohar, general director of the Mexican National Cancer Institute. In 2007, Mexico guaranteed access to Herceptin for all women with breast cancer through a public insurance programme.

“We would love to have better access to better drugs,” Dr. Mohar said. “This debate is going to heat up.” — New York Times News Service

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