Pomalidomide Treatment in Relapsed/Refractory Multiple Myeloma Patients—Real-World Data From Hungary

An elevated systemic inflammation index is related to an inferior response to pomalidomide and dexamethasone treatment in patients with relapsed and refractory multiple myeloma

Introduction

The systemic inflammation index (SII) might serve as an indicator of the equilibrium between the inflammatory and immune responses. The aim of the study was to determine the clinical value and prognostic significance of SII in the cohort of multiple myeloma (MM) patients treated with a regimen of pomalidomide and dexamethasone (Pd).

Material and methods

This retrospective, real-life study included patients who received a Pd regimen in our centre between November 2018 and July 2022. The systemic inflammation index was calculated from peripheral blood counts of platelets, neutrophils, and lymphocytes collected shortly before commencement of Pd treatment using the equation: SII = N × P/L, where N, P, and L are the respective counts per litre of peripheral blood for neutrophils, platelets, and lymphocytes.

Results

The study group consisted of 54 patients. Most patients received Pd as the third (38.9%) or fourth (37.0%) line of treatment. The median number of completed treatment cycles was 5 (IQR: 1-12). The median progression-free survival (PFS) was 6.8 months and overall survival (OS) 14.8 months. High SII (> 374) was an independent prognostic factor for PFS (HR = 3.0, 95% CI: 1.4-6.3, p < 0.01) and OS (HR = 2.2, 95% CI: 1.0-4.6, p = 0.04). In the low SII group, the respective median PFS and OS values were 9.6 and 21.7 months, compared to 2.6 (p = 0.018) and 5.5 months (p = 0.035) in the high SII group.

Conclusions

The systemic inflammation index has prognostic significance in MM patients treated with Pd. A high SII predicts a poorer outcome in pretreated MM patients undergoing Pd treatment evaluation. As such, it may well be a key factor for guiding subsequent treatment decisions.

The real-world use and efficacy of pomalidomide for relapsed and refractory multiple myeloma in the era of CD38 antibodies

Pomalidomide-dexamethasone (Pd) has been a standard care treatment for relapsed and refractory multiple myeloma since 2013. However, the outcomes of Pd after exposure to CD38 antibodies are not known. Here we describe the real-world use and efficacy of pomalidomide in a Danish, nationwide cohort of daratumumab-exposed patients. We identified 328 patients that were treated with pomalidomide. Of these, 137 received Pd, 65 daratumumab-pomalidomide-dexamethasone (DPd), 43 pomalidomide-cyclophosphamide-dexamethasone (PCd), 19 carfilzomib-pomalidomide-dexamethasone (KPD), 11 pomalidomide-bortezomib-dexamethasone (PVd), and 52 pomalidomide in other combinations. Patients treated with Pd in this cohort had a partial response or better (≥ PR) rate of 35.8% and median time to next treatment (mTNT) of 4.9 months, almost identical to the results of previous prospective clinical trials. Although treatment with the various pomalidomide-containing triplet regimens resulted in higher ≥ PR rates (PCd: 46.5%, PVd: 63.6%, DPd: 55.4%, KPd: 63.2%), the mTNT achieved was not significantly better than with Pd in most cases (PCD: 5.4, PVD: 5.3, DPD: 4.7 months). The exception to this was KPd (mTNT 7.4 months), but this regimen was mainly used earlier in the course of the disease (median time from diagnosis 2.3 years vs. 3.7-4.3 years). The most important predictor of outcomes was not the choice of index regimen (p = 0.72), but prior exposure (p = 0.0116). Compared to CD38 antibody-naïve patients, triple-class-exposed patients achieved reduced ≥ PR rate (38.0% vs. 47.3%), shorter mTNT (4.0 vs. 5.9 months), and shorter median overall survival (12.4 vs. 24.2 months) with pomalidomide treatment.