Study Suggests New Treatment Option for Some Lymphomas

Adapted from the NCI Cancer Bulletin.

Updated findings from a large European clinical trial indicate that patients with some types of lymphoma could initially be treated with the chemotherapy drug bendamustine (Treanda®) and the targeted agent rituximab (Rituxan®). The majority of patients in the trial had follicular lymphoma, and the remainder had either mantle cell or indolent (slow-growing) lymphoma.

Findings from the trial, which involved 514 newly diagnosed patients, were reported by lead investigator Mathias J. Rummel, M.D., Ph.D., of the University Hospital Giessen in Germany at the 2012 American Society of Clinical Oncology annual meeting.

After a median follow-up of nearly 4 years, patients who received the two-drug combination lived more than twice as long without their disease progressing (69.5 months versus 31.2 months) as patients who received the standard first-line treatment, rituximab and a chemotherapy regimen called CHOP, or R-CHOP.

Despite the improvement in progression-free survival in patients treated with bendamustine and rituximab, overall survival did not differ between the two patient groups. As a result, some researchers may hesitate to promote the drug combination as the new standard of care for all patients with these lymphomas, according to Wyndham Wilson, M.D., Ph.D., head of the Lymphoma Therapeutics Section in NCI’s Center for Cancer Research, who was not involved in the study.

Although there was a higher incidence of mild skin reactions in patients who received bendamustine and rituximab, other major side effects were far less common, including neuropathy and the dangerous drops in white blood cell count known as neutropenia. Only 4 percent of patients who received bendamustine and rituximab required treatment with granulocyte colony-stimulating factor to counter neutropenia compared with 20 percent of patients who received R-CHOP.

Dr. Rummel cited several reasons why the bendamustine-containing combination did not lead to improved overall survival: First, almost half of the patients whose cancer progressed after R-CHOP crossed over to treatment with bendamustine and rituximab. Second, these types of lymphoma grow slowly and tend to have better long-term survival, so patients would need to be followed for a longer time before a difference in overall survival might be seen.

Bendamustine, which was developed in Germany and has been used in Europe for decades to treat blood cancers, is approved in the United States for the treatment of indolent lymphoma, but only for cancers that have progressed following treatment with a regimen that includes rituximab. Bendamustine is also approved for the treatment of chronic lymphocytic leukemia.