Add-on ixazomib yields survival gains in post-transplant myeloma

The combination of lenalidomide plus ixazomib in the maintenance treatment of patients with post-transplant myeloma leads to better progression-free survival (PFS) compared with lenalidomide alone in historical controls, according to a study.

A total of 64 patients with newly diagnosed multiple myeloma and underwent stem cell infusion participated in the study, of whom 41 (64.0 percent) were aged ≥60 years and 42 (65.6 percent) were men. Fourteen patients had high-risk cytogenetic features, and nine had International Staging System (ISS) stage 3 disease.

All patients were initiated on maintenance therapy with lenalidomide and ixazomib within 60–180 days of autologous stem cell transplant (ASCT). They received a median of 37 cycles of maintenance therapy, with a mean of 39 cycles.

Most patients achieved deeper response over time with maintenance therapy. The complete response (CR)/stringent (s)CR rate was 43 percent, and median overall survival was not reached over a median follow-up of 62 months. Median PFS was 73 months and has not been reached for those with ISS stage 1 disease.

The rate of very good partial response (VGPR) or higher increased from 65.6 percent at baseline to 89.1 percent with maintenance therapy, with the CR/sCR rate jumping from 4.6 percent to 42.2 percent.

Commonly reported grade 3/4 adverse events included neutropenia, leukopenia, thrombocytopenia, lung infections, diarrhoea, and maculopapular rash. Nine patients developed second primary malignancies.

Toxicity resulted in dose reductions in ixazomib and lenalidomide in 20 and 31 patients, respectively. Meanwhile, toxicity-related discontinuation of ixazomib was documented in four patients. Grade 1/2 neuropathy occurred in 22 patients and led to reduction or discontinuation of ixazomib in two patients.

The findings suggest that the combination of lenalidomide and ixazomib as maintenance therapy in the post-ASCT setting is safe and clinically effective, with the potential to provide an additional benefit in deepening the response to ASCT in patients with multiple myeloma.