Drug shows promise for hard-to-treat lymphoma

An experimental drug developed by Seattle Genetics Inc. and Takeda Pharmaceutical Co. wiped out tumors in one-third of patients with hard-to-treat Hodgkin's lymphoma and reduced the cancer by half in an additional 40 percent, a study has found.

Overall, 94 percent of 102 patients had their tumors shrink by at least a quarter, an "unheard-of" level of improvement in people who had failed other treatments, said study leader Robert Chen, an assistant professor at City of Hope, a nonprofit cancer center in Duarte, Calif. He presented the results yesterday at the American Society of Hematology meeting in Orlando, Fla.

The drug, SGN-35, may be approved by federal regulators late next year and could generate $420 million in annual revenue by 2015, said analyst Jason Kantor of RBC Capital Markets in San Francisco.

The treatment uses an antibody to target and bind with a protein on the surface of lymphoma cells, then blasts them with a cancer-killing chemical. This keeps the drug out of the bloodstream and away from healthy tissue, avoiding the side effects of standard chemotherapy, Chen said.

"We had a hint this was going to be an effective agent from an earlier trial but we had no idea it was going to be this good," said Chen, who also works as a consultant for Seattle Genetics, based in Bothell, Wash. "Patients tolerated this drug very well."

About 8,500 people in the United States are diagnosed every year with Hodgkin's lymphoma and 1,300 of them die, according to the National Cancer Institute. The disease attacks the lymphatic system, part of the body's disease-fighting mechanism, and can lead to enlargement of the spleen, the lymph nodes and other tissues. It also causes night sweats, fever, weight loss and fatigue in about 40 percent of patients, Chen said.

Patients tend to develop lymphoma either as young adults in their 20s or 30s or when they're in their 60s. While the disease can be cured in about 70 percent of patients, Chen said, his study tested the drug in people who relapsed or didn't respond to treatment.

The patients were mostly young, with a median age of 31, and had advanced cases of the disease, Chen said. All had been treated with chemotherapy and stem cell transplants drawn from their own blood.

"When patients have failed multiple lines of treatment, as these patients had, it's usually a very difficult discussion," Chen said. "It's tough for the patients and for us because there's no standard therapy. The only options are palliative care or clinical trials."