BEIJING — Every few days, Houston businessman Richard Weissenborn receives injections of a radical new cancer drug at a hospital here.

The treatment aims to check his head and neck cancers by replacing mutant genes with good copies. The treatment is still experimental in the United States, but in China, it was approved for marketing after a few years of testing.

The Chinese scientists behind the drug, Gendicine, see it as a milestone in the country's efforts to catch up with the West, proof that China can develop some of the world's most advanced medicine.

But a company in the United States says the Chinese drug is basically stolen property, rushed to market with inadequate testing and in violation of patent rights.

The dispute is the latest clash between the two countries in the broad field known as intellectual property. China in recent decades has prospered largely because of a talent for copying. The country duplicates goods others created but figures out how to make them more cheaply.

For years, that tactic focused on items like watches, purses and DVDs. But increasingly, China is moving up the value chain, copying such high-value goods and services as architectural techniques, cars and drugs.

The dispute over the gene-therapy drug is especially revealing in that scientific innovation is a pillar of American business. If other countries can learn to beat the United States to market with drugs and other technologically advanced goods, that could spell economic trouble in America.

According to Peng Zhaohui, founder of SiBiono GeneTech, which created the gene-therapy cancer drug and put it on the market in the breakneck span of seven years, the treatment is the latest accomplishment of Chinese genetic engineering, built on information publicly available in medical literature.

U.S. RESEARCH HURDLES

American scientists tell a different story.

David Nance, chief executive of Introgen Therapeutics of Austin, Texas, said SiBiono's drug is the same one that he and an American colleague developed 15 years ago. He said that while Introgen's drug was making its way past U.S. research hurdles, SiBiono stole the technology and rushed it to market, thereby infringing on Introgen's patents.

Introgen says it holds 258 worldwide patents, four of them in China. No lawsuit has been filed. Nance declined to comment about specific patents or to describe the company's Chinese patent position in detail, citing possible future litigation.

Peng, a former University of California at Los Angeles medical researcher, denies that his company is infringing on any patents held by Nance's company.

"In the West, there are still people who are suspicious about this first gene-therapy product and have doubts about its origins and clinical practices. But after 50 years of fighting cancer, humans haven't had any obvious advancement in treatment other than this," Peng said.

"It is absolutely untrue that our drugs are the same," Peng added. "There's a huge difference — the only thing that is the same is the name" of the cancer-related gene the two companies target with their therapies.

Meanwhile, the drug is beginning to transform the way cancer patients are treated in China, offering an alternative to traditional treatments with harsh side effects, such as surgery and chemotherapy. As of last month, more than 5,000 patients had been treated with the drug.

Weissenborn, 64, has traveled to Beijing three times to receive the Chinese gene-therapy treatment. He's a believer in the drug and is angry it is not available in the United States.

"If I died today, I have already prolonged my life and have a quality of life that I could not have with any other cancer treatment," he said.

By the time most patients arrive at the Beijing-Haidian Hospital Gene Therapy Center, the only one that accepts foreigners, they've exhausted other treatments.

Weissenborn had been told the only way to get rid of the cancer in his throat was radical surgery that would carve off part of his face. Arve Johnsen, 34, a fisherman from Oslo with brain cancer, was told he had a 3 percent chance of surviving the next five years. Deborah Weatherby-Falk, a nurse from Vancouver, Canada, had a recurrent tumor between her left eye and nose, a tricky place to operate.

INJECTIONS SHIPPED

Weatherby-Falk, an intensive-care nurse, read every medical journal article about the treatment she could get her hands on before she got on the plane.

"I understand the criticisms," Weatherby-Falk said. "I came despite them."

A handful of foreign patients, fewer than 100, get the injections shipped via courier to their homes. Most seek treatment from the Haidian clinic's director, Li Dinggang, a former Johns Hopkins University School of Medicine researcher. So far, more than 310 foreigners and 550 Chinese nationals have been treated with the gene-therapy drug here.

Since the treatment is still considered experimental in most places, insurance won't cover it. Patients must wire a $10,000 cash deposit, to be applied against the $20,000 cost of a two-month course of treatment, before they set foot in the clinic.