Pomalidomide extends survival in multiple myeloma
A new immunomodulatory drug under review by the FDA was found to significantly increase progression-free and overall survival in persons with multiple myeloma, including older patients, according to research reported at the annual meeting of the American Society of Hematology, held December 8–11, 2012, in Atlanta, Georgia.
The safety and efficacy of oral pomalidomide was evaluated in a phase 2 study, in combination with low-dose dexamethasone, a corticosteroid used in standard treatment of multiple myeloma. The 226 patients all had relapsed and refractory multiple myeloma (RRMM); had received at least two prior therapies, including lenalidomide and bortezomib; and had experienced disease progression within 60 days of their last treatment.
“When multiple myeloma no longer responds to two major classes of drugs, the average patient survival is only 9 months and progression-free survival only 5 months,” noted Sundar Jagannath, MD, first author of the study as well as director of the Multiple Myeloma Program and professor of medicine at The Tisch Cancer Institute at The Mount Sinai Medical Center, New York, New York, in a statement issued by The Mount Sinai Hospital/Mount Sinai School of Medicine. “Pomalidomide represents an exciting development for our patients.”
Half the patients were randomized to receive pomalidomide plus low-dose dexamethasone, and half were assigned to pomalidomide monotherapy. At progression, patients receiving pomalidomide monotherapy could be switched to the combination therapy at the investigator's discretion. All patients also received daily low-dose aspirin as thromboprophylaxis. The mean age of the 113 patients in the pomalidomide-plus-dexamethasone group was 64 years (range 34 to 88 years); 99 (88%) were no older than 75 years.
The administration of pomalidomide plus dexamethasone yielded a median progression-free survival of 4.6 months and overall survival of 16.5 months. In an age subgroup analysis of the pomalidomide-plus-dexamethasone users, median progression-free survival was 4.7 months in persons up to age 65 years (median overall survival 19.7 months), and 3.7 months in persons older than age 65 years (median overall survival 11.8 months).
Pomalidomide was well-tolerated, associated with side effects common to this drug class, according to the Mount Sinai statement. The most common grade 3 or grade 4 adverse events occurring in more than 5% of patients were neutropenia (41%), anemia (22%), pneumonia (22%), thrombocytopenia (19%), fatigue (14%), dyspnea (13%), leucopenia (10%), back pain (10%), and urinary tract infection (10%).
Overall, 21 (19%) of the patients receiving pomalidomide and dexamethasone died during the study, most commonly due to progressive multiple myeloma. Other causes of death included infections, cerebral/intracranial/subarachnoid hemorrhage, acute respiratory distress syndrome, and suicide (by one patient with a history of severe depression).