New regimens and directions in the management of newly diagnosed multiple myeloma

Hospital facility characteristics and socioeconomic factors on outcomes and treatment in patients with multiple myeloma: National Cancer Database analysis

Previous studies have shown that socioeconomic factors play an important role in multiple myeloma (MM) health outcomes. We postulated that the type of treatment facilities and their volume of cases also affect overall survival, utilization of various therapies including palliative care services in newly diagnosed MM. Using the National Cancer Database (NCDB), we analyzed 174,551 newly diagnosed MM participants from across the country. We found that at high volume facility centers (over 90^th percentile of new patient volume from 2004 to 2016), the median overall survival (OS) was 62.3 months versus 35.3 months at lower volume facilities (p <0.001). Similarly, high volume academic cancer centers had an improved median OS of 66.4 months (65.3-67.4 CI) versus 39.2 months (37.9-40.4 months CI) in lower volume academic centers (p <0.001). The odds of utilizing chemotherapy, immunotherapy, and autologous transplants were higher in academic cancer centers compared to community cancer centers, after adjusting for demographic and socioeconomic factors (OR 1.10, 1.23, and 2.06 respectively, all with p<0.001). There was significantly decreased odds of receiving palliative care (OR 0.89, 95% CI 0.85-0.93) in high volume facilities compared to low volume. Palliative care services were more frequently utilized at integrated network cancers and comprehensive community cancer centers compared to community cancer centers, with similar odds of receiving palliative care between community and academic facility types. Our results likely reflect increased provider experience and resources in higher volume and academic facilities. This highlights the need to integrate resources and improve access to community programs.

The Effect of Belantamab Mafodotin on Primary Myeloma–Stroma Co-Cultures: Asymmetrical Mitochondrial Transfer between Myeloma Cells and Autologous Bone Marrow Stromal Cells

Belantamab mafodotin (belamaf) is an afucosylated monoclonal antibody conjugated to the microtubule disrupter monomethyl auristatin-F (MMAF) that targets B cell maturation antigen (BCMA) on the surface of malignant plasma cells. Belamaf can eliminate myeloma cells (MMs) through several mechanisms. On the one hand, in addition to inhibiting BCMA-receptor signaling and cell survival, intracellularly released MMAF disrupts tubulin polymerization and causes cell cycle arrest. On the other hand, belamaf induces effector cell-mediated tumor cell lysis via antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis. In our in vitro co-culture model, the consequences of the first mentioned mechanism can be investigated: belamaf binds to BCMA, reduces the proliferation and survival of MMs, and then enters the lysosomes of malignant cells, where MMAF is released. The MMAF payload causes a cell cycle arrest at the DNA damage checkpoint between the G2 and M phases, resulting in caspase-3-dependent apoptosis. Here, we show that primary MMs isolated from different patients can vary widely in terms of BCMA expression level, and inadequate expression is associated with extremely high resistance to belamaf according to our cytotoxicity assay. We also reveal that primary MMs respond to increasing concentrations of belamaf by enhancing the incorporation of mitochondria from autologous bone marrow stromal cells (BM-MSCs), and as a consequence, MMs become more resistant to belamaf in this way, which is similar to other medications we have analyzed previously in this regard, such as proteasome inhibitor carfilzomib or the BCL-2 inhibitor venetoclax. The remarkable resistance against belamaf observed in the case of certain primary myeloma cell cultures is a cause for concern and points towards the use of combination therapies to overcome the risk of antigen escape.

The BLM helicase is a new therapeutic target in multiple myeloma involved in replication stress survival and drug resistance

Multiple myeloma (MM) is a hematologic cancer characterized by accumulation of malignant plasma cells in the bone marrow. To date, no definitive cure exists for MM and resistance to current treatments is one of the major challenges of this disease. The DNA helicase BLM, whose depletion or mutation causes the cancer-prone Bloom's syndrome (BS), is a central factor of DNA damage repair by homologous recombination (HR) and genomic stability maintenance. Using independent cohorts of MM patients, we identified that high expression of BLM is associated with a poor outcome with a significant enrichment in replication stress signature. We provide evidence that chemical inhibition of BLM by the small molecule ML216 in HMCLs (human myeloma cell lines) leads to cell cycle arrest and increases apoptosis, likely by accumulation of DNA damage. BLM inhibition synergizes with the alkylating agent melphalan to efficiently inhibit growth and promote cell death in HMCLs. Moreover, ML216 treatment re-sensitizes melphalan-resistant cell lines to this conventional therapeutic agent. Altogether, these data suggest that inhibition of BLM in combination with DNA damaging agents could be of therapeutic interest in the treatment of MM, especially in those patients with high BLM expression and/or resistance to melphalan.

Emerging and current treatment combinations for transplant-ineligible multiple myeloma patients

INTRODUCTION

Availability of new classes of novel agents has led to a radical switch in treatment paradigms for newly diagnosed transplant-ineligible multiple myeloma (NDTIMM) patients, providing an opportunity to significantly enhance the depth of response and extend survival outcomes.

AREAS COVERED

Treatment regimens including proteasome inhibitors (PIs), immunomodulatory drugs (IMiDs) and/or monoclonal antibodies (mAbs), have achieved recent regulatory approval for NDTIMM, while novel combinations and newer agents are currently being explored. This review discusses the current landscape and possible treatment development of NDTIMM.

EXPERT OPINION

Bortezomib-lenalidomide-dexamethasone (VRd), daratumumab-bortezomib-melphalan-prednisone (DaraVMP) and daratumumab-lenalidomide-dexamethasone (DaraRd) represent new standard of care (SOC) treatments for NDTIMM patients, based on phase III trials showing their superior efficacy as compared with previous SOCs. The possibility of improving results by incorporating second generation PIs or using quadruple regimens has also been explored and different trials are still ongoing. Newer agents and innovative immunotherapies targeting B-cell maturation antigen have the potential to change the therapeutic landscape in coming years. Personalized approaches based on frailty-adapted, risk-based and minimal residual disease driven paradigms are under investigation.

Treatment Strategy for Multiple Myeloma to Improve Immunological Environment and Maintain MRD Negativity

Improving the immunological environment and eradicating minimal residual disease (MRD) are the two main treatment goals for long-term survival in patients with multiple myeloma (MM). Immunomodulatory drugs (IMiDs), monoclonal antibody drugs (MoAbs), and autologous grafts for autologous stem cell transplantation (ASCT) can improve the immunological microenvironment. ASCT, MoAbs, and proteasome inhibitors (PIs) may be important for the achievement of MRD negativity. An improved immunological environment may be useful for maintaining MRD negativity, although the specific treatment for persistent MRD negativity is unknown. However, whether the ongoing treatment should be continued or changed if the MRD status remains positive is controversial. In this case, genetic, immunophenotypic, and clinical analysis of residual myeloma cells may be necessary to select the effective treatment for the residual myeloma cells. The purpose of this review is to discuss the MM treatment strategy to "cure MM" based on currently available therapies, including IMiDs, PIs, MoAbs, and ASCT, and expected immunotherapies, such as chimeric antigen receptor T cell (CAR-T) therapy, via improvement of the immunological environment and maintenance of MRD negativity.

Clinical significance of the lymphocyte-to-monocyte ratio in multiple myeloma patients with negative minimal residual disease: a single-center retrospective analysis

Minimal residual disease (MRD) is a surrogate marker for survival in multiple myeloma (MM), while the lymphocyte-to-monocyte ratio (LMR) is a prognostic factor associated with the patients' immunological status. We retrospectively evaluated the clinical impact of MRD negativity and LMR. MRD was analyzed by multicolor flowcytometry (threshold, 1 × 10-5). Fifty-eight patients (median age 70 years) who achieved complete response were included in this study. Twenty-two patients received autologous stem cell transplantation, 14 received daratumumab-based chemotherapy, and 22 received another treatment. Forty-one (70.7%) patients achieved MRD negativity. Over the median follow-up time of 15.1 months, PFS in MRD-negative patients was significantly longer than in MRD-positive patients (P = 0.020). In addition, a high LMR at MRD assessment was associated with MRD negativity (P = 0.019) and long PFS (P = 0.009). Finally, neither MRD negativity nor high LMR at MRD assessment was associated with significantly shorter PFS compared with MRD positivity or low LMR (P = 0.002). In conclusion, high LMR was associated with MRD negativity and can be used as a predictor of long PFS. Change of treatment strategy might be essential for patients with MRD positivity and high LMR at MRD assessment due to their short PFS.