Treatment of Relapsed/Refractory Myeloma (excluding T-cell redirection therapy)
Category: Treatment of Relapsed/Refractory Myeloma (excluding T-cell redirection therapy)
Real-world Treatment Patterns, Effectiveness, and Safety of Daratumumab-based Regimens in Chinese Patients with Multiple Myeloma: Final Analysis of the MMY4032 Study
Luqun Wang
Doctor
Qilu Hospital of Shandong University
Daratumumab, a monoclonal antibody targeting CD38, has demonstrated efficacy in several multiple myeloma (MM) clinical trials. However, real-world data of daratumumab in a Chinese population which would reflect routine clinical practice is still needed. Daratumumab appeared effective and tolerable in Chinese MM patients in the first interim analysis of the real-world MMY4032 study (ChiCTR2200055491). Here we present the final analysis of MMY4032.
Methods:
This is an observational study across 13 sites enrolled Chinese patients with MM who started daratumumab after August 1, 2019, and were to continue daratumumab at the time of study initiation (November 3, 2021) or started daratumumab after study initiation, and who had received ≤3 prior lines of therapy (LOT), until up to 2 years, lost to follow-up or death for the last patient. Data were collected retrospectively using medical charts for patients who initiated daratumumab after August 1, 2019, but prior to study initiation, and were collected prospectively thereafter.
Results:
Overall, 212 patients were enrolled in the study, with a median follow-up of 23.7 months and median duration of treatment (DOT) was 11.7 months. Of these 212 patients, 35.4% completed the study including 11.3% still under ongiong daratumumab treatment and the reasons for discontinuation were withdrawal by patient (29.2%), death (20.3%), lost to follow-up (7.1%) and other (8.0%).
Of the 185 patients evaluable for response, the overall response rate (ORR) was 76.8%, with 57.2%≥very good partial response (VGPR) and 39.4%≥complete response (CR). Of 212 patients, the median progression-free survival (PFS) was 34.1 months, while the median overall survival (OS) and time to next treatment (TTNT) were not reached, with 36-month OS of 72.8% and 24-month TTNT rates of 72.3%. Notably, higher response rates were observed with earlier daratumumab LOT (Table 1). The 36-month PFS/OS and 24-month TTNT rates were higher with earlier daratumumab LOT (Table 2). These findings highlight the enhanced effectiveness of daratumumab-based regimens when used in earlier treatment settings.
Adverse drug reactions (ADRs) and serious adverse events (SAEs) were reported in 22.2% and 16.5% of patients, respectively. Importantly, no new safety concerns were identified with daratumumab-based regimens.
Table.1 Response Rate in each LOT
| ORR | ≥CR | ≥VGPR | |
| 1L(n=28),% | 89.3 | 46.4 | 75 |
| 2L(n=107),% | 83.2 | 46.7 | 67.3 |
| 3L(n=26),% | 57.7 | 19.2 | 23.1 |
| >3L(n=24),% | 54.2 | 20.8 | 29.2 |
| 36-month PFS | 24-month TTNT | 36-month OS | |
| 1L(n=35),% | 53.7 | 72.9 | 76.6 |
| 2L(n=115),% | 57.8 | 78.5 | 81.2 |
| 3L(n=33),% | 25.6 | 61.8 | 58.2 |
| >3L(n=29),% | 18.1 | 58.5 | 45.9 |
In the final analysis with a longer follow-up, daratumumab-based regimens continue to demonstrate robust real-world effectiveness and manageable safety profiles in Chinese MM patients, particularly in earlier LOTs. These findings support the clinical utility of daratumumab and highlight its role in improving long-term outcomes in MM.