In the phase III OPTIMISMM trial, reported by Richardson et al in The Lancet Oncology, researchers found that the addition of pomalidomide to bortezomib/dexamethasone improved progression-free survival in relapsed or refractory multiple myeloma previously treated with lenalidomide.

Dr. Richardson discusses the OPTIMISMM trial at EHA 2018

Primary Endpoint

The primary endpoint was progression-free survival in the intention-to-treat population, as assessed by independent review committee.

Results

The median follow-up was 15.9 months. Median progression-free survival was 11.20 months in the pomalidomide group vs 7.10 months in the control group (hazard ratio = 0.61, < .0001).

Among 391 patients refractory to lenalidomide in the last lenalidomide-containing regimen, the hazard ratio favoring the pomalidomide group was 0.65 (95% confidence interval = 0.50-0.84).

Pomalidomide, bortezomib, and dexamethasone significantly improved progression-free survival compared with bortezomib and dexamethasone

Adverse Events

The most common grade 3 or 4 adverse events in the pomalidomide group were neutropenia (42% vs 9% in the control group; febrile neutropenia in 3% vs 0%), infections (31% vs 18%), and thrombocytopenia (27% vs 29%). Serious adverse events occurred in 57% vs 42% of patients. Treatment-related death occurred in six patients in the pomalidomide group (due to pneumonia in two, unknown cause in two, cardiac arrest in one, and cardiorespiratory arrest in one) and in two patients in the control group (pneumonia in one patient and hepatic encephalopathy in another).

The investigators concluded, “Patients with relapsed or refractory multiple myeloma who previously received lenalidomide had significantly improved progression-free survival when treated with pomalidomide, bortezomib, and dexamethasone compared with bortezomib and dexamethasone. Adverse events accorded with the individual profiles of pomalidomide, bortezomib, and dexamethasone. This study supports use of pomalidomide, bortezomib, and dexamethasone as a treatment option in patients with relapsed or refractory multiple myeloma who previously received lenalidomide.”

References:

Richard PG et al. Pomalidomide, bortezomib, and dexamethasone for patients with relapsed or refractory multiple myeloma previously treated with lenalidomide (OPTIMISMM): a randomised, open-label, phase 3 trial. Lancet Oncol. 2019 May 13. pii: S1470-2045(19)30152-4. doi: 10.1016/S1470-2045(19)30152-4. [Epub ahead of print]

Myeloma News Phase 3 OPTIMISMM Trial Demonstrates Improved Progression-Free Survival