Salvage therapy with "Dara-KDT-P(A)CE" in heavily pretreated, high-risk, proliferative, relapsed/refractory multiple myeloma

A single-day polychemotherapy regimen with proteasome inhibitor combinations for relapsed/refractory myeloma in the era of novel therapies

PCAB (prednisone, cyclophosphamide, doxorubicin, carmustine) is a single-day regimen previously used for induction and now in relapsed/refractory multiple myeloma (RRMM). We retrospectively analysed the outcomes of 85 patients from five Australian centres. These included 30 patients (35.3%) who received PCAB with one additional agent (bortezomib most frequently). Median age of the patients was 65 years (37-80), with a median of four (1-8) prior lines of therapy. ORR was 37% (CR 4.9%). Median progression free survival and overall survival were 4.4 months (95% CI 3.5-6.7) and 7.4 months (95% CI 6.4-10.2), respectively. Extramedullary disease (EMD) was associated with shorter survival. Grade 3 or 4 cytopenia and febrile neutropenia occurred in 76.2% and 39.1%, respectively, with six (7.1%) treatment-related mortalities. Median inpatient stay was 3.3 days/28-day cycle (IQR 0.6-13), and for patients who died, a median of 20.2% of days alive were spent inpatient (IQR 6.4-39.1%). Three patients were successfully bridged to CAR T-cell therapy using PCAB, despite being penta-exposed and having EMD. PCAB may be considered as a useful salvage therapy amongst other polychemotherapy regimens in late relapse. Further studies is warranted to investigate and define its role as a bridging therapy to novel therapeutics.

Extramedullary relapse of multiple myeloma presenting as space-occupying lesion in liver treated with daratumumab, pomalidomide, dexamethasone and bendamustine

Extramedullary relapse in patients with multiple myeloma (MM) is often associated with loss of biochemical response and the appearance of measurable residual disease in the bone marrow. Fever is an unusual presenting manifestation of MM. Treatment of extramedullary relapse in patients progressing on proteasome inhibitors, anti-CD38 monoclonal antibodies and immunomodulatory drugs is challenging, as access to chimeric antigen receptor T-cells and bispecific antibodies is limited. We report a case of relapsed MM who presented with fever and hepatic space-occupying lesion mimicking hepatocellular carcinoma. In this case report, we also present our experience of using a novel combination regimen comprising Dara-Pom-Benda-Dexa (daratumumab, pomalidomide, dexamethasone and bendamustine) for relapsed MM.

CAR T-cell therapy in multiple myeloma: mission accomplished?

ABSTRACT

B-cell maturation antigen (BCMA) chimeric antigen receptor (CAR) T cells are the most potent treatment against multiple myeloma (MM). Here, we review the increasing body of clinical and correlative preclinical data that support their inclusion into firstline therapy and sequencing before T-cell-engaging antibodies. The ambition to cure MM with (BCMA-)CAR T cells is informed by genomic and phenotypic analysis that assess BCMA expression for patient stratification and monitoring, steadily improving early diagnosis and management of side effects, and advances in rapid, scalable CAR T-cell manufacturing to improve access.

Cyclophosphamide etoposide dexamethasone as salvage and bridging therapy in relapsed refractory and extramedullary multiple myeloma

Patients with relapsed refractory multiple myeloma (RRMM) that are triple-exposed to immunomodulatory drugs, proteasome inhibitors, and anti-CD38 monoclonal antibodies have a poor prognosis. Standard treatment for these patients has not been established. Patients with extramedullary disease or secondary plasma cell leukemia often display high tumor cell proliferation and might therefore be susceptible to chemotherapy. While current regimens are often platinum-based, we present single-center data on 70 patients with RRMM who were treated with cyclophosphamide, etoposide, and dexamethasone (CED) after a median of four lines of therapy. An overall response rate of 52% was achieved after 1-6 cycles, with 23% of patients having a very good partial response. Comparable response rates and survival were observed in patients with extramedullary disease and high-risk cytogenetics. Treatment resulted in non-hematological °III-IV adverse events in 31% of patients. No treatment-related deaths occurred. The median progression-free and overall survival were 6.2 and 10.9 months, respectively. 23% of patients were bridged to autologous stem cell transplantation (ASCT) or chimeric antigen receptor (CAR) T cell therapy. In summary, CED is an effective treatment regimen for RRMM cases with a tolerable safety profile and suitable as bridging therapy to CAR T cell treatment and ASCT.

Revisiting the Role of Alkylating Agents in Multiple Myeloma: Up-to-Date Evidence and Future Perspectives

From the 1960s to the early 2000s, alkylating agents (e.g., melphalan, cyclophosphamide, and bendamustine) remained a key component of standard therapy for newly-diagnosed or relapsed/refractory multiple myeloma (MM). Later on, their associated toxicities (including second primary malignancies) and the unprecedented efficacy of novel therapies have led clinicians to increasingly consider alkylator-free approaches. Meanwhile, new alkylating agents (e.g., melflufen) and new applications of old alkylators (e.g., lymphodepletion before chimeric antigen receptor T-cell [CAR-T] therapy) have emerged in recent years. Given the expanding use of antigen-directed modalities (e.g., monoclonal antibodies, bispecific antibodies, and CAR-T therapy), this review explores the current and future role of alkylating agents in different treatment settings (e.g., induction, consolidation, stem cell mobilization, pre-transplant conditioning, salvage, bridging, and lymphodepleting chemotherapy) to ellucidate the role of alkylator-based regimens in modern-day MM management.

Th17.1 cell driven sarcoidosis-like inflammation after anti-BCMA CAR T cells in multiple myeloma

Pseudo-progression and flare-up phenomena constitute a novel diagnostic challenge in the follow-up of patients treated with immune-oncology drugs. We present a case study on pulmonary flare-up after Idecabtagen Vicleucel (Ide-cel), a BCMA targeting CAR T-cell therapy, and used single-cell RNA-seq (scRNA-seq) to identify a Th17.1 driven autoimmune mechanism as the biological underpinning of this phenomenon. By integrating datasets of various lung pathological conditions, we revealed transcriptomic similarities between post CAR T pulmonary lesions and sarcoidosis. Furthermore, we explored a noninvasive PET based diagnostic approach and showed that tracers binding to CXCR4 complement FDG PET imaging in this setting, allowing discrimination between immune-mediated changes and true relapse after CAR T-cell treatment. In conclusion, our study highlights a Th17.1 driven autoimmune phenomenon after CAR T, which may be misinterpreted as disease relapse, and that imaging with multiple PET tracers and scRNA-seq could help in this diagnostic dilemma.

Patient Characteristics, Treatment Patterns, and Outcomes in Triple-Class Exposed Relapsed/Refractory Multiple Myeloma Patients, a Retrospective Observational Study Using Czech Registry Data

BACKGROUND

Although novel therapies improved prognosis of multiple myeloma (MM) patients, clinical outcomes in the multi-refractory population are still poor.

PATIENTS AND METHODS

We reviewed data from the Czech Registry of Monoclonal Gammopathies, identified and characterized triple-class exposed (3CE) relapsed/refractory MM patients, treatment patterns after 3CE, assessed overall survival (OS), progression-free survival (PFS), time to next treatment (TTNT), explored cohorts with and without triple- and penta-refractoriness.

RESULTS

In 83 3CE patients who started subsequent therapies, the median OS was 14.2 months (95% CI, 8.5-19.9), PFS 6.2 months (95% CI, 3.9-8.5), and TTNT 7.2 months (95% CI, 4.6-9.8). Triple- and penta-class refractory patients had a significantly worse prognosis in all outcomes. Their life expectancy was shorter, the disease progression started earlier, and the TTNT was shorter, which increased likelihood of becoming refractory to more therapies. Time-to-event results from the first index date and all index dates analyses were very similar.

CONCLUSION

Similar to previous studies from the US and Europe, our results show a high disease burden. Introduction of novel therapies, such as CAR-T cells, new bispecific and trispecific monoclonal antibodies, and other drugs, is expected to bring significant benefits to these patients.

How I treat triple-class refractory multiple myeloma

Immunomodulatory imide drugs (IMiDs), proteasome inhibitors (PIs) and anti-CD38 monoclonal antibodies (MoAbs) are the pillars of modern multiple myeloma (MM) therapy. The prognosis of patients with MM that became refractory to these three classes (triple-class refractory [TCR]) is historically poor. Observational studies indicate an overall response rate of ~30% and overall survival inferior to 1 year with existing therapies. While no randomised trial has been completed in this setting, several agents exploring new mechanisms of action showed activity in TCR MM in single-arm trials, including anti-B-cell maturation antigen (BCMA) chimeric antigen receptor T cells, anti-BCMA antibody-drug conjugates and exportin 1 (XPO1) inhibitors. Among agents in development, anti-BCMA bispecific T-cell engagers (TCE), and non-BCMA TCEs demonstrated activity in most patients. Additionally, specific agents may exhibit unique activity in biologically defined patient subsets, as exemplified by venetoclax in t(11;14) MM. The main open questions in TCR MM are preferred sequence of existing therapies, the utility of sequential use of agents with similar mechanism of action, but different immunotherapy target and the relative efficacy of the different anti-BCMA platforms. Here, we summarise the existing literature and provide general guidance on selecting therapy for this challenging and heterogenous group of patients.