Clinical outcomes of pomalidomide-based and daratumumab-based therapies in patients with relapsed/refractory multiple myeloma: A real-world cohort study in China

Abstract

Background: Comparative investigations evaluating the efficacy of pomalidomide-based (Pom-based) versus daratumumab-based (Dara-based) therapies in patients with relapsed/refractory multiple myeloma (RRMM) remain scarce, both in randomized controlled trials and real-world studies.

Methods: This retrospective cohort study included 140 RRMM patients treated with Pom-based or Dara-based or a combination of pomalidomide and daratumumab (DPd) regimens in a Chinese tertiary hospital between December 2018 and July 2023.

Results: The overall response rates (ORR) for Pom-based (n = 48), Dara-based (n = 68), and DPd (n = 24) groups were 57.8%, 84.6%, and 75.0%, respectively (p = 0.007). At data cutoff on August 1, 2023, the median progression-free survival (PFS) was 5.7 months (95% CI: 5.0-6.5) for the Pom-based group, 10.5 months (5.2-15.8) for the Dara-based group, and 6.7 months (4.0-9.3) for the DPd group (p = 0.056). Multivariate analysis identified treatment regimens (Dara-based vs. Pom-based, DPd vs. Pom-based) and Eastern Cooperative Oncology Group performance status (ECOG PS) as independent prognostic factors for PFS. In the subgroups of patients aged >65 years, with ECOG PS ≥2, lines of therapy ≥2, extramedullary disease or double-refractory disease (refractory to both lenalidomide and proteasome inhibitors), the superiority of Dara-based regimens over Pom-based regimens was not evident. A higher incidence of infections was observed in patients receiving Dara-based and DPd regimens (Pom-based 39.6% vs. Dara-based 64.7% vs. DPd 70.8%, p = 0.009).

Conclusions: In real-world settings, Pom-based, Dara-based, and DPd therapies exhibited favorable efficacy in patients with RRMM. Dara-based therapy yielded superior clinical response and PFS compared to Pom-based therapy.

Keywords: daratumumab; multiple myeloma; pomalidomide; recurrence; refractory.

FIGURE 1

Response rates by regimens. CR, complete response; Dara‐based, daratumumab‐based; DPd, daratumumab plus pomalidomide and dexamethasone; MR, minimal response; Pom‐based, pomalidomide‐based; PR, partial response; VGPR, very good partial response.

FIGURE 2

Kaplan–Meier curves for PFS (2A), TTNT (2B), and OS (2C) of Pom‐based, Dara‐based, and DPd groups. Log‐rank tests were used to evaluate differences between groups. Dara‐based, daratumumab‐based; DPd, daratumumab + pomalidomide and dexamethasone; Pom‐based, pomalidomide‐based.

FIGURE 3

Post hoc subgroup analysis for ORR (3A) and PFS (3B). ORR are shown as number/patients (%), and PFS are shown as median (95% CI). Unadjusted results are presented. Dara‐based, daratumumab‐based; DPd, daratumumab plus pomalidomide and dexamethasone; ECOG PS, Eastern Cooperative Oncology Group performance status; eGFR, estimated glomerular filtration rate by Cockcroft‐Gault equation; HR, hazard ratio; ISS, International Staging System; LOT, line of therapy; NA, not available; PI, proteasome inhibitor; Pom‐based, pomalidomide‐based; RR, risk ratio.