Once-weekly better than twice-weekly carfilzomib dosing for relapsed, refractory MM

Once-weekly treatment with carfilzomib at the higher 70-mg/m² dose appears to improve survival in patients with relapsed and refractory multiple myeloma (RRMM) compared with the twice-weekly 27-mg/m² dosing regimen, regardless of patient and disease characteristics, according to data from the phase III ARROW study.

The analysis included 478 patients, of whom 240 were treated with carfilzomib once-weekly at 70 mg/m² and 238 with twice-weekly at 27 mg/m² in addition to dexamethasone. Baseline characteristics were generally balanced between treatment arms across subgroups. Researchers performed subgroup analyses defined by age (<65, 65–74, or ≥75 years), renal function (creatinine clearance <50, ≥50–<80, or ≥80 mL/min), number of prior therapies (two or three) and bortezomib-refractory status (yes or no).

Overall, the once-weekly regimen increased progression-free survival (median, 11.2 vs 7.6 months; hazard ratio [HR], 0.69, 95 percent confidence interval [CI], 0.54–0.88; p=0.0029) compared with the twice-weekly regimen, as it did response rates and depth of response.

Furthermore, the once-weekly regimen reduced the risk of progression or death (HR range, 0.60–0.85) and improved overall response rates in nearly all the examined subgroups. This was consistent with the results in the overall population.

The safety profiles of once-weekly dosing across subgroups were also in line with those observed in the overall population.

The present data highlight a favourable benefit–risk profile of once-weekly 70-mg/m² carfilzomib regimen and support such dosing as an appropriate treatment option for patients with RRMM, regardless of age, prior lines of therapy and bortezomib-refractory status, according to the researchers.