CHICAGO May 31 A new drug for the most common
form of leukemia in adults improves survival for patients whose
disease has worsened despite standard treatment, according to
late-stage study findings released on Saturday.
Ibrutinib, sold by Pharmacyclics Inc and Johnson &
Johnson under the brand name Imbruvica, was approved by
U.S. regulators for treatment of chronic lymphocytic leukemia in
The therapy "beat the pants off" of ofatumumab, or Arzerra,
marketed by GlaxoSmithKline Plc, in the Phase 3 trial,
said Dr. John Byrd, the study's lead investigator and a
professor of medicine at the Ohio State University Comprehensive
Cancer Center in Columbus, Ohio.
The trial involved 391 patients with chronic lymphocytic
leukemia that had progressed after two or more prior therapies.
Standard treatment for such patients is a combination of
chemotherapy and an antibody drug, such as Arzerra.
The results were presented at the American Society of
Clinical Oncology (ASCO) meeting on Saturday in Chicago.
At a median follow-up of 9.4 months, the study found that
ibrutinib lowered the risk of death by 57 percent compared with
ofatumumab. Researchers said they expect the trial to result in
median overall survival in the range of several years.
At median follow-up, 86 percent of patients on ibrutinib had
responded to the drug and were continuing treatment with minimal
side effects, compared with response rates between 35 percent
and 40 percent for standard therapies, Dr. Byrd said.
Side effects associated with ibrutinib included diarrhea,
minor bleeding and heart arrhythmias.
"These results provide a compelling new treatment option for
patients with chronic lymphocytic leukemia, including older
adults with this disease, and will significantly change
(physicians') practice," Dr. Olatoyosi Odenike, a leukemia
expert at the University of Chicago said in an ASCO statement.
Odenike was not involved in the study.
The U.S. Food and Drug Administration in February approved
Imbruvica as a secondary treatment for chronic lymphocytic
leukemia. It was previously approved for mantle cell lymphoma
patients who have tried other therapies.
Studies are also under way to test the drug as an initial
treatment for chronic lymphocytic leukemia.
Imbruvica is an oral drug designed to target an enzyme known
as Bruton's tyrosine kinase and block the function of certain
Drugs in a similar class are under development by companies
including AbbVie and Gilead Sciences Inc.
Chronic lymphocytic leukemia, a slowly progressing form of
blood cancer, is diagnosed in about 16,000 Americans and will
kill around 4,600 every year, according to the American Cancer
(Reporting By Deena Beasley; Editing by Michele Gershberg and