ATLANTAIn newly diagnosed multiple myeloma patients, lenalidomide (Revlimid) plus low-dose dexamethasone led to superior overall survival, compared with the standard regimen of lenalidomide plus high-dose dexamethasone. Vincent Rajkumar, MD, of the Mayo Clinic, reported the 2-year results of the phase III ECOG trial at ASH 2007 (abstract 74).
A total of 445 patients were randomized to receive either four cycles of lenalidomide 25 mg/d orally on days 1-21 every 28 days plus standard high-dose (HD) dexamethasone 40 mg orally on days 1-4, 9-12, and 17-20 (480 mg total) every 28 days, or the same dose of lenalidomide plus low-dose (LD) dexamethasone 40 mg on days 1, 8, 15, and 22 (160 mg total) every 28 days. The median follow-up time was 21 months.
The best overall response rate within four cycles was 82% for the HD arm vs 71% for the LD arm. The rates of complete response/very good partial response were 52% and 42%, respectively. Median duration of response has not yet been achieved in either arm at this time point.
At 2 years, overall survival was significantly superior in the LD arm (87% vs 75% for the HD arm , P = .009). These values compare to the 1-year survival rates of 96% and 88%, respectively, that were reported at ASCO 2007 (LBA-8025).
For patients who continued on treatment past 6 months, 1-year overall survival was 99% for LD and 97% for HD.
The survival advantage was independent of age, although in patients less than 65 years, the 2-year survival advantage with LD was not as large (91% vs 85% for HD).
Major nonhematologic toxicities of grade 3 or higher were significantly lower in the LD arm, compared with HD, including deep vein thrombosis/pulmonary embolism (9% vs 25%, P < .001) and non-neuropathic weakness (4% vs 10%, P = .008). Neutropenia (grade 3 or higher) was greater on the LD arm (19% vs 12%), but the rate of infections was lower with the LD treatment (7% vs 14%, P = .03).