In the treatment of multiple myeloma (MM), outcomes of patients intolerant or refractory to an immunomodulatory drug (IMiD) and bortezomib have traditionally been poor. Newer drugs have since been introduced for the treatment of MM. Kumar and co-investigators performed a retrospective study to estimate outcomes in patients with relapsed MM, who have become refractory to current generation IMiDs and proteasome inhibitors.
They enrolled 543 patients with relapsed MM who had received at least 3 prior lines of therapy and who were refractory to both an IMiD (lenalidomide or pomalidomide) and a proteasome inhibitor (bortezomib or carfilzomib), and who had also been exposed to an alkylating agent. The time patients met the above criteria was defined as T0.
The median estimated follow-up from diagnosis and from T0 was 61 months and 13 months, respectively. The median number of lines of therapy prior to T0 was 4, and 48% of patients had a prior transplant. The median overall survival (OS) from T0 for the entire cohort was 13 months. The median progression-free survival from T0 was 5 months, and the median OS from time 0 was 15 months. The OS for the 81 patients with no treatment post T0 was only 2 months.
The investigators conclude that these survival rates “appear to be better than we had seen historically in patients refractory/intolerant to bortezomib and IMiDs, highlighting the increased treatment options available for these patients.” However, the response rate to sequential regimens decreases, which suggests the development of drug resistance.
Kumar S, et al. ASH 2016. Abstract 4414.