Survival and treatment patterns of patients with relapsed or refractory multiple myeloma in France - a cohort study using the French National Healthcare database (SNDS).

Over the past decade, several drugs have been approved for the treatment of relapsed or refractory multiple myeloma (RRMM). This retrospective study, using the French National Healthcare database (SNDS), describes the treatment patterns and outcomes of patients with RRMM treated in real-world clinical practice in France. Patients were adults, with a diagnosis of multiple myeloma, who initiated second-line (2L) treatment approved for use in France between 2014 and 2018; this included bortezomib, carfilzomib, daratumumab, ixazomib, lenalidomide, or pomalidomide. Data were analyzed overall, by first-line (1L) autologous stem cell transplant (ASCT) status and by lenalidomide treatment status at 2L. In total, 12987 patients with RRMM were included in the study (mean age 69.5 years); 27% received an ASCT at 1L, and 30% received a lenalidomide-sparing regimen at 2L. Overall, and among the ASCT and non-ASCT subgroups, most patients received a bortezomib-based regimen at 1L, whereas lenalidomide-based regimens were most common at 2L. Among patients who received a lenalidomide-sparing regimen at 2L, this was most often a proteasome inhibitor-based regimen. Mortality rate was 26.1/100 person-years, and median (95% confidence interval) survival from 2L initiation was 32.4 (31.2-33.6) months. Survival differed by various factors, shorter survival was reported in the non-ASCT group, those receiving a lenalidomide-sparing regimen at 2L, older patients (≥ 70 years), and those with multiple comorbidities. This analysis provides insight into the real-world use of approved novel MM treatments and highlights an ongoing unmet need to improve outcomes, particularly for selected patient groups.

Interest of Pet Imaging in Multiple Myeloma.

The interest of 18Fluoro-deoxyglucose (FDG) positron emission tomography (PET) imaging in the management of patients with multiple myeloma (MM) for the workup at diagnosis and for therapeutic evaluation has recently been demonstrated. FDG-PET is a powerful imaging tool for bone lesions detection at initial diagnosis with high sensitivity and specificity values. The independent pejorative prognostic value on progression-free survival (PFS) and overall survival (OS) of baseline PET-derived parameters (presence of extra-medullary disease (EMD), number of focal bone lesions (FLs), and maximum standardized uptake values [SUVmax]) has been reported in several large independent prospective studies. During therapeutic evaluation, FDG-PET is considered as the reference imaging technique, because it can be performed much earlier than MRI which lacks specificity. Persistence of significant FDG uptake after treatment, notably before maintenance therapy, is an independent pejorative prognostic factor, especially for patients with a complete biological response. So FDG-PET and medullary flow cytometry are complementary tools for detection of minimal residual disease before maintenance therapy. However, the definition of PET metabolic complete response should be standardized. In patients with smoldering multiple myeloma, the presence of at least one hyper-metabolic lytic lesions on FDG-PET may be considered as a criterion for initiating therapy. FDG-PET is also indicated for initial staging of a solitary plasmacytoma so as to not disregard other bone or extra-medullary localizations. Development of nuclear medicine offer new perspectives for MM imaging. Recent PET tracers are willing to overcome limitations of FDG. (11)C-Methionine, which uptake reflects the increased protein synthesis of malignant cells seems to correlate well with bone marrow infiltration. Lipid tracers, such as Choline or acetate, and some peptide tracers, such as (68) Ga-Pentixafor, that targets CXCR4 (chemokine receptor-4, which is often expressed with high density by myeloma cells), are other promising PET ligands. 18F-fludarabine and immuno-PET targeting CD138 and CD38 also showed promising results in preclinical models.

Targeting Bcl-2 for the treatment of multiple myeloma.

Despite advances in the treatment of multiple myeloma, the disease still remains incurable for the majority of patients. The overexpression of anti-apoptotic proteins (i.e., Bcl-2, Bcl-XL or Mcl-1) is a hallmark of cancer and favors tumor cell survival and resistance to therapy. The oral drug venetoclax is the first-in-class Bcl-2-specific BH3 mimetic. In myeloma, in vitro sensitivity to venetoclax is mainly observed in plasma cells harboring the t(11;14) translocation, a molecular subgroup associated with high Bcl-2 and low Mcl-1/Bcl-XL expression. In addition with Bcl-2 members expression profile, functional tests as BH3 profiling or in vitro BH3 mimetic drug testing also predict sensitivity to the drug. Phase 1 clinical trials recently confirmed the efficacy of venetoclax monotherapy in heavily pretreated myeloma patients, mostly in patients with t(11;14). In combination with the proteasome inhibitor bortezomib, venetoclax therapy was found to be feasible and allowed promising response rate in relapsed myeloma patients, independent of t(11;14) status. The present review summarizes the current knowledge, "from bench to bedside", about venetoclax for the treatment of multiple myeloma.

Elotuzumab for the treatment of multiple myeloma.

New agents are awaited for the treatment of multiple myeloma and research is ongoing for the development of monoclonal antibodies (MoAbs) targeting the tumor cells. One of the most promising MoAb is elotuzumab, the only humanized IgG1 MoAb specifically targeting CS1 (SLAMF7), a cell surface glycoprotein that is highly expressed in plasma cells. Preclinical and clinical data on elotuzumab will be presented in this article.