UPDATE 2-FDA approves Roche leukemia drug Gazyva

Fri Nov 1, 2013 12:05pm EDT

Nov 1 (Reuters) - U.S. regulators on Friday approved Roche Holding AG's new drug for patients with chronic lymphocytic leukemia (CLL) who have not previously been treated for one of the most common forms of blood cancer.

The U.S. Food and Drug Administration said the new drug, Gazyva (obinutuzumab), works by helping certain immune system cells to attack cancer cells, and is meant to be used with a standard chemotherapy treatment for the disease called chlorambucil.

It is the first drug to be approved by the FDA after receiving its "breakthrough therapy" designation, the agency said. The new designation indicates the medicine may offer substantial improvement over current treatments for patients with serious or life-threatening diseases.

Roche in July presented initial data from a late-stage trial that showed Gazyva, previously known as GA101, delayed disease progression in patients with CLL longer than its top-seller Rituxan. Detailed data demonstrating the magnitude of the improvement over Rituxan is expected to be presented at the American Society of Hematology annual meeting in December.

The Swiss drugmaker's $7 billion-a-year Rituxan loses European patent protection late this year, although it is not known when cheaper generic, or biosimilar, forms of the drug will be allowed on the market.

In the meantime, Roche hopes to switch as many patients as possible to Gazyva from Rituxan prior to the introduction of cheaper biosimilar versions of the older drug. Rituxan, also known as MabThera, is an antibody against white blood cells that have the so-called CD20 protein on their surface. It is used to treat lymphomas, leukemias, transplant rejection and rheumatoid arthritis.

Gazyva was designed to be more potent than Rituxan in attacking such white blood cells, known as B cells, from which many blood cancers, such as CLL and lymphomas, originate.

Gazyva will carry a prominent "black-box" warning on its package insert label, noting that it can reactivate Hepatitis B infections and can cause a rare brain infection called progressive multifocal leukoencephalopathy. PML, which can be fatal, has also been seen as a rare side effect associated with long-term use of some multiple sclerosis treatments.

Roche's Genentech unit said Gazyva will become available in the United States in about two weeks and is still awaiting approval in Europe and other markets.

The FDA said more than 15,000 Americans will be diagnosed with chronic lymphocytic leukemia this year, and almost 5,000 will die from the disease.

Roche shares were up 0.8 percent in Switzerland.