Outcomes of triple-class refractory multiple myeloma patients at a single clinic: A retrospective study

Multiple myeloma (MM) is an incurable B cell malignancy requiring complex treatments with a variety of drugs. Patients often become refractory to proteasome inhibitors, immunomodulatory agents, and anti-CD38 monoclonal antibodies (mAb), and termed triple class refractory (TCR), associated with a poor prognosis.

We performed a retrospective analysis of data regarding the outcomes of TCR MM patients at a single clinic specializing in the care of multiple myeloma patients.

A retrospective chart review was conducted among 117 patients with TCR MM at a single clinic. Patients' progression-free survival (PFS), overall survival (OS), cytogenetics, lines of prior therapy (LOT), and first treatment they received after the development of TCR disease were determined.

The median time from diagnosis to development of TCR disease from diagnosis was 47 months (range: 1.5-191.0; n = 104) and the median LOT prior to TCR disease development was 5 (range: 2-13; n = 117). From the development of TCR disease, patients in our study showed a median OS of 18.9 months (range: 0.03-60.0) and a median PFS of 3.1 months (range: 0.1-55.1). The most commonly utilized first treatment regimens used after TCR disease development were mAb-containing combinations (n = 42). Venetoclax-based regimens showed the longest median PFS at 12.4 months (n = 14).

This median OS of 18.9 months recorded at a single clinic provides real-world data regarding the survival of TCR MM patients highlighting the need for improvement in prognosis for this subset of patients.