To China For a U.S. Cancer Drug?

"We don't promise a cure," Nance said. "It's different in every patient -- some respond and get rid of their cancer, and some respond to a degree. Some patients just don't respond at all."

Even as Western researchers proceeded slowly because of problems in gene-therapy trials, SiBiono plowed ahead in China. The company's studies, most of them published only in Chinese medical literature, showed significant benefits, if not cures, from the p53 treatment. But skeptics said it was unclear whether initial results, such as tumor shrinkage, would lead to longer life for patients. Other researchers have said the initial trials had too few patients, fewer than 200.

Savio Woo, chairman of gene and cell medicine at the Mount Sinai School of Medicine in New York, has visited SiBiono's scientists in the southern city of Shenzhen. He said the company's work superficially "looks spic and span; on paper it looks fine." But Woo said he remains concerned because raw data for the trial had not been shared. "No one knows how clinical trials are done in China," he said. "Do they have quality control?"

Indeed, a broad scandal regarding food and drug safety has been unfolding in China in recent years, and the former head of China's drug-regulatory agency -- the same agency that approved Gendicine for marketing -- was sentenced to death recently for taking bribes.

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, had a recurrent tumor between her left eye and nose, a tricky place to operate.

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.

Li combines gene therapy with traditional treatments like surgery, chemotherapy and radiation along with Chinese herbal remedies. He estimates that about 70 percent of his patients obtain positive results but warns that no one knows why some patients benefit and others don't.

"I have to tell patients the truth," Li said. "Their cancer condition is very late. In this condition, they can come to China, but no one can guarantee anything."

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.

Weissenborn first arrived last fall, when his cancer had spread from his tongue to his throat and lymph nodes. He had trouble swallowing and was losing weight. He considered suicide and alternative treatments from Mexico. "I would believe a witch doctor if he said he could help me at that time," Weissenborn said.

A broker that specializes in matching cancer patients with experimental treatments led him to Li's clinic. Doctors reading medical scans told him that after two courses of treatment, his cancer had disappeared.

He came back in March for a checkup, though, and the doctors told him his cancer had returned.

Researcher Richard Drezen in New York contributed to this report.