Genentech Inc. and Biogen Idec Inc. announced that their drug Rituxan combined with chemotherapy did well in patients with chronic lymphatic leukemia. The combined treatment met its goal of improving the survival rate in patients diagnosed with relapsed Chronic Lymphocytic Leukemia, or CLL, with no progression of the disease.

Rituxan was first approved in 1997 to treat non-Hodgkin’s lymphoma. Later it was approved for other uses, including against rheumatoid arthritis in 2006. Rituxan, known generically as rituximab, had sales last year of $2.3 billion in the U.S. alone, compared to $2.07 billion in 2006.

The study dubbed REACH is the second study evaluating the combined treatment of Rituxan plus chemotherapy in treating CLL, the most common adult leukaemia. REACH is a randomized study of 552 patients with previously treated CD20-positive CLL, who were randomized to receive either a combined treatment of Rituxan and chemotherapy, or chemotherapy alone.

The study showed the drug, combined with fludarabine and cyclophosphamide chemotherapy, improved patient survival compared with chemotherapy alone. The trial data is now under independent review, the companies said, “for U.S. regulatory purposes.”

Earlier this year, another late-stage study found that a similar Rituxan combo improved progression-free survival in patients with CLL who had not previously received treatment.

The drug is already approved by the FDA for the following indications: relapsed or refractory, low-grade or follicular, CD20-positive, B-cell NHL as a single agent; previously untreated follicular, CD20-positive, B-cell NHL in combination with CVP chemotherapy; non-progressing (including stable disease), low-grade, CD20-positive B-cell NHL, as a single agent, after first-line CVP chemotherapy; previously untreated diffuse large B-cell, CD20-positive NHL in combination with CHOP or other anthracycline-based chemotherapy regimens.

Lymphotic leukemia, the most frequent type of leukaemia in adults, will affect 15,000 people in 2008, according to the American Cancer Society.   

In September, a fatal case of progressive multifocal leukoencephalopathy, or PML, in a patient treated with arthritis drug Rituxan has prompted pharmaceutical company Genentech to revise the labeling of the drug. It was the first case when PML occurred in a patient taking the drug for arthritis. The woman developed the infection more than a year and a half after discontinuing treatment with Rituxan, the US Food and Drug Administration said. Genetech said the risk of PML, a virus infection that usually occurs in patients with impaired-mediated immunity, is already mentioned on Rituxan’s label.

Genentech, based in California and Biogen, based in Massachussetts are developing separate large-stage clinical trials testing Rituxan as a treatment for lupus nephritis, an inflammation of the kidneys. Previous studies have showed that the drug performed no better than a placebo against lupus erythematosus, commonly called lupus.   

On Monday, Genetech Inc announced the results of a Phase III study investigating the addition of Avastin to Tarceva compared with Tarceva alone for the treatment of patients with advanced non-small cell lung cancer. The results were discouraging, as the combined treatment didn’t prolong the lives of patients with advanced lung cancer.