Page 231 - 2021_06-Haematologica-web

LETTERS TO THE EDITOR
The survival impact of maintenance lenalidomide: an analysis of real-world data from the Canadian Myeloma Research Group national database
Multiple myeloma (MM) is an incurable malignancy of mature plasma cells. Treatment of MM focuses on obtaining a deep and durable remission to improve over- all and progression-free survival (PFS). Patients with good functional status ≤70 years of age are generally consid- ered eligible for treatment with bortezomib-based induc- tion chemotherapy followed by autologous stem cell transplant (ASCT) which has demonstrated a PFS and overall survival (OS) benefit in large, randomized con- trolled trials.1-6 The use of lenalidomide maintenance (LM) following ASCT is based on four large randomized control trials and a meta-analysis demonstrating improvement in both PFS and OS.2,5,7-9
Currently, data validating the use of LM in the real- world, Canadian landscape, in which LM is publicly funded, is limited.10-13 An analysis of the survival impact
and adverse effects of LM in large, real-world cohorts is of considerable importance. In order to address this knowledge gap, we conducted a retrospective, observa- tional study of patients meeting International Myeloma Working Group (IMWG) criteria for MM who were treat- ed with upfront bortezomib-based induction chemother- apy followed by ASCT.14 Data was collected from the Canadian Myeloma Research Group Database (CMRG- DB), a comprehensive collaborative data-sharing plat- form that pools data from academic cancer centers across Canada and includes legacy data dating back to 2007. The project was approved by Health Research Ethics Board of Alberta. We included patients receiving either lenalidomide monotherapy as maintenance or no mainte- nance (non-LM). Charts were reviewed with regard to demographics, response and adverse effects. The primary outcomes of this analysis were PFS, OS and progression- free survival 2 (PFS2) defined as time from initiation of second line chemotherapy to death, relapse or last fol- low-up. Progression was defined as per the IMWG crite- ria with an additional endpoint of near complete
Table 1. Baseline characteristics of lenalidomide maintenance and non-lenalidomide maintenance groups.
Characteristic
Patients
Age at diagnosis, median (range) in years
No maintenance Maintenance P NN
533 723
57.9 (32.4 – 71.4) 58.1 (30.4 – 72.2) 0.711
Male (%)
Laboratory values at diagnosis, median (range)
Hemoglobin (g/L) Platelets (x109/L) Neutrophils (x109/L) Calcium (mmol/L) Creatinine level (mmol/L)
ISS, Median ISS I (%) ISS II (%) ISS III (%) Missing (%)
High risk cytogenetics
del 17p* (%) t(4:14) (%) t(14:16) (%) Missing (%)
Immunoglobulin subtype IgG (%)
IgA (%)
IgD (%)
IgM (%)
Light chain (%)
Induction regimen used
CyBor/CyBorD/P (%) RVD / RVDD* / VTD (%) VD/P (%)
VD-PACE (%)
Bortezomib monotherapy (%)
332 (62.3)
104 (39-169) 221 (20-576) 3.4 (0.3-15.3) 2.5 (1.6-4.4) 96 (42-2,705) II
122 (26.8) 167 (36.6) 167 (36.6) 77
56/315 (17.8)
26/307 (8.5) 30/302 (9.9) 8/176 (4.6) 218
283/483 (58.6) 101/483 (20.9) 1/483 (0.21) 1/483 (0.21) 97/483 (20.1)
646 (89.4) 9 (1.24) 68 (9.41) 0 (0)
0 (0)
443 (61.3)
107.5 (53-173) 219 (10-740) 3.3 (0.3-17.3) 2.4 (1.7-5.7) 84 (32-2,700) II
232 (35.9) 252 (39.0) 162 (25.1) 77 137/567 (24.2) 76/560 (13.6) 58/545 (10/6) 13/451 (2.9) 156
386/696 (55.5) 148/696 (21.2) 0/696 (0) 2/696 (0.29) 160/696 (23)
370 (69.4)
18 (3.38)
135 (25.3)
1 (0.19)
9 (1.7)
0.714
0.0012 0.7758 0.3659 0.9322 0.0112
<0.0001
0.028
0.026 0.746 0.298
0.542‡
<0.001
0.017‡
‡Fisher’s exact test. Ig: immunglobulin; ISS: injury severity score; Cy: cyclophosphamide; V: bortezomid (also abbreviated as Bor in standard combination regime). P: prednisone; D: dexamethasone; D*: doxil; R: lenalidomide; T: thalidomide; PACE: cisplatin, adriamycin, cyclophosphamide & etoposide.
<0.001
-
<0.001‡
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