Phase I Study of Venetoclax Plus Daratumumab and Dexamethasone, With or Without Bortezomib, in Patients With Relapsed or Refractory Multiple Myeloma With and Without t(11;14)

Biomarker-directed therapy in multiple myeloma

PURPOSE OF REVIEW

Multiple myeloma is currently treated with a one-size-fits-all approach despite significant heterogeneity in patient outcomes and disease molecular constitution. A personalised approach would tailor therapy to unique patient or disease characteristics.

RECENT FINDINGS

Well established prognostic biomarkers such as cytogenetic risk and patient frailty status are being evaluated as potential predictive biomarkers. Specifically, treatment intensity can be augmented in high-risk patients or conversely attenuated in those at lower risk or lower ability to withstand treatment toxicities. Alternatively, targeted therapy can be rationally designed to exploit vulnerable pathways in myeloma cells as identified using predictive biomarkers. The t(11;14) translocation, found in approximately 15-20% of myeloma cases, is a leading biomarker for response to BCL-2 inhibitors such as venetoclax.

SUMMARY

Active research efforts exploring venetoclax combination therapies, as well as new generation BCL-2 inhibitors are underway. Following the development of venetoclax, numerous other cellular pathways are under investigation as candidate predictive biomarkers to rationally inform newer targeted therapies in myeloma.

Precision medicine for multiple myeloma: The case for translocation (11;14)

The t(11;14) translocation is among the most prevalent cytogenetic abnormalities in multiple myeloma (MM), distinguished by its unique features and biology that have been thoroughly explored for decades. What further sets this MM subtype apart is its oscillating prognostic significance, from initially being considered a favorable alteration to intermediate risk and potential future reclassification as favorable risk. Despite not being inherently a high-risk alteration indicative of an aggressive phenotype, it appears that t(11;14)-MM is less responsive to novel agents like proteasome inhibitors and immunomodulatory drugs which have otherwise transformed the disease's treatment landscape, perhaps partially explained by its reduced propensity for immunoglobulin production and oligosecretory nature. However, its distinct reliance on Bcl-2 has heightened its sensitivity to venetoclax. Further subclassification based on morphological and genomic characteristics could enhance our prediction models of treatment responses and enable more tailored therapeutic strategies for patients. This review aims to encapsulate the existing research evidence in this area.

Exposure-response relationships of venetoclax in combination with carfilzomib and dexamethasone in relapsed/refractory t(11;14) multiple myeloma patients

Venetoclax is a first in class BCL-2 inhibitor, currently under investigation for the treatment of t(11;14) multiple myeloma (MM). The objective of this analysis was to characterize the exposure-efficacy and exposure-safety relationships of venetoclax when combined with carfilzomib and dexamethasone (VenKd) in t(11;14)-positive relapsed or refractory (R/R) MM patients from a phase 2 study. Fifty-seven patients receiving VenKd or Kd were included in the analysis. Efficacy endpoints included progression-free survival and clinical response rates of overall response, very good partial response or better and complete response or better. Grade ≥ 3 neutropenia, Grade ≥ 3 infections, Grade ≥ 3 treatment-emergent adverse events and any grade serious treatment-emergent adverse events were evaluated. The analysis demonstrated that adding venetoclax to Kd resulted in increased ORR, ≥VGPR and ≥ CR rates compared to the control arm. Within the venetoclax treatment arms (VenKd), no significant exposure-efficacy relationships were observed for ORR and ≥ VGPR rates. Higher ≥ CR rates trended with higher venetoclax exposures. While both 400 mg and 800 mg venetoclax in VenKd arms were generally tolerated, higher rates of Grade ≥ 3 neutropenia were observed with higher venetoclax exposures. Higher venetoclax exposures however were not associated with increased rates of Grade ≥ 3 treatment-emergent adverse events, Grade ≥ 3 infections, or serious treatment-emergent adverse events (any grade). These results confirm the benefit of adding venetoclax to carfilzomib and dexamethasone and support continued evaluation of venetoclax 400-800 mg once daily in this combination in t(11;14)-positive R/R MM patients. NCT02899052 registered April 18, 2017.

Combination of bortezomib and venetoclax targets the pro-survival function of LMP-1 and EBNA-3C of Epstein-Barr virus in spontaneous lymphoblastoid cell lines

Epstein-Barr virus (EBV) manipulates the ubiquitin-proteasome system and regulators of Bcl-2 family to enable the persistence of the virus and survival of the host cells through the expression of viral proteins in distinct latency patterns. We postulate that the combination of bortezomib (proteasome inhibitor) and venetoclax (Bcl-2 inhibitor) [bort/venetoclax] will cause synergistic killing of post-transplant lymphoproliferative disorder (PTLD) through targeting the pro-survival function of latent viral proteins such as latent membrane protein-1 (LMP-1) and EBV nuclear antigen-3C (EBNA-3C). Bort/venetoclax could synergistically kill spontaneous lymphoblastoid cell lines (sLCLs) derived from patients with PTLD and EBV-associated hemophagocytic lymphohistiocytosis by inducing DNA damage response, apoptosis and G1-S cell cycle arrest in a ROS-dependent manner. Bortezomib potently induced the expression of Noxa, a pro-apoptotic initiator and when combined with venetoclax, inhibited Mcl-1 and Bcl-2 simultaneously. Bortezomib prevented LMP-1 induced proteasomal degradation of IκBα leading to the suppression of the NF-κB signaling pathway. Bortezomib also rescued Bcl-6 from EBNA-3C mediated proteasomal degradation thus maintaining the repression of cyclin D1 and Bcl-2 causing G1-S arrest and apoptosis. Concurrently, venetoclax inhibited Bcl-2 upregulated by either LMP-1 or EBNA-3C. Bort/venetoclax decreased the expression of phosphorylated p65 and Bcl-2 at serine 70 thereby suppressing the NF-κB signaling pathway and promoting apoptosis, respectively. These data corroborated the marked suppression of the growth of xenograft of sLCL in SCID mice (p<0.001). Taken together, the combination of bortezomib and venetoclax targets the pro-survival function of LMP-1 and EBNA-3C of Epstein-Barr virus in spontaneous lymphoblastoid cell lines.

Venetoclax resistance leads to broad resistance to standard-of-care anti-MM agents, but not to immunotherapies

ABSTACT

To our knowledge, venetoclax is the first example of personalized medicine for multiple myeloma (MM), with meaningful clinical activity as a monotherapy and in combination in patients with myeloma harboring the t(11:14) translocation. However, despite the high response rates and prolonged progression-free survival, a significant proportion of patients eventually relapse. Here, we aim to study adaptive molecular responses after the acquisition of venetoclax resistance in sensitive t(11:14) MM cell models. We therefore generated single-cell venetoclax-resistant t(11:14) MM cell lines and investigated the mechanisms contributing to resistance as well as the cells' sensitivity to other treatments. Our data suggest that acquired resistance to venetoclax is characterized by reduced mitochondrial priming and changes in B-cell lymphoma-2 (BCL-2) family proteins' expression in MM cells, conferring broad resistance to standard-of-care antimyeloma drugs. However, our results show that the resistant cells are still sensitive to immunotherapeutic treatments, highlighting the need to consider appropriate sequencing of these treatments after venetoclax-based regimens.

Combination of BCL-2 inhibitors and immunotherapy: a promising therapeutic strategy for hematological malignancies

The rapid development of high-throughput sequencing in recent years has facilitated great progress in the molecular-targeted therapy of hematological malignancies, including leukemia, lymphoma, and multiple myeloma. BCL-2 inhibitors are among the most important molecular-targeted agents. Immunotherapy for hematologic malignancy has rapidly increased in popularity in recent years and has been proven to improve the overall survival rate. However, few clinical studies have investigated combination therapy with BCL-2 inhibitors and immunotherapies, such as immune molecule-targeted drugs or immune cell adoptive therapy. In this review, we discuss the drug discovery process, current clinical application status, and resistance and tolerance issues associated with BCL-2 inhibitors. We emphasize their important role in regulating the immune system and propose that the combination of BCL-2 inhibitors with immunotherapy may be one of the most promising treatment methods for hematologic malignancies.

Clinical outcomes of pomalidomide-based and daratumumab-based therapies in patients with relapsed/refractory multiple myeloma: A real-world cohort study in China

BACKGROUND

Comparative investigations evaluating the efficacy of pomalidomide-based (Pom-based) versus daratumumab-based (Dara-based) therapies in patients with relapsed/refractory multiple myeloma (RRMM) remain scarce, both in randomized controlled trials and real-world studies.

METHODS

This retrospective cohort study included 140 RRMM patients treated with Pom-based or Dara-based or a combination of pomalidomide and daratumumab (DPd) regimens in a Chinese tertiary hospital between December 2018 and July 2023.

RESULTS

The overall response rates (ORR) for Pom-based (n = 48), Dara-based (n = 68), and DPd (n = 24) groups were 57.8%, 84.6%, and 75.0%, respectively (p = 0.007). At data cutoff on August 1, 2023, the median progression-free survival (PFS) was 5.7 months (95% CI: 5.0-6.5) for the Pom-based group, 10.5 months (5.2-15.8) for the Dara-based group, and 6.7 months (4.0-9.3) for the DPd group (p = 0.056). Multivariate analysis identified treatment regimens (Dara-based vs. Pom-based, DPd vs. Pom-based) and Eastern Cooperative Oncology Group performance status (ECOG PS) as independent prognostic factors for PFS. In the subgroups of patients aged >65 years, with ECOG PS ≥2, lines of therapy ≥2, extramedullary disease or double-refractory disease (refractory to both lenalidomide and proteasome inhibitors), the superiority of Dara-based regimens over Pom-based regimens was not evident. A higher incidence of infections was observed in patients receiving Dara-based and DPd regimens (Pom-based 39.6% vs. Dara-based 64.7% vs. DPd 70.8%, p = 0.009).

CONCLUSIONS

In real-world settings, Pom-based, Dara-based, and DPd therapies exhibited favorable efficacy in patients with RRMM. Dara-based therapy yielded superior clinical response and PFS compared to Pom-based therapy.

New Therapies on the Horizon for Relapsed Refractory Multiple Myeloma

Despite improved treatments, most patients with multiple myeloma (MM) will experience relapse. Several novel agents have demonstrated activity and tolerability in early phase clinical trials. Venetoclax is a B-cell lymphoma 2 (Bcl-2) inhibitor with activity in patients with t(11;14) and/or Bcl-2 expression. Iberdomide and mezigdomide are cereblon E3 ligase modulators with higher potency, immunomodulatory, and antiproliferative activity compared with lenalidomide and pomalidomide. They have shown promising activity in heavily pretreated patients. Modakafusp alfa is an immunocytokine that targets interferons to CD38+ cells. It has demonstrated single agent activity in relapsed/refractory MM in the phase 1 setting.

Use of venetoclax in t(11;14) positive relapsed/refractory multiple myeloma: A systematic review

BACKGROUND

The plasma cell malignancy, multiple myeloma (MM), remains incurable despite advanced treatment protocols. Overexpression of Bcl-2 (an anti-apoptotic protein), in MM harboring the translocation (11;14), contributes to resistance to prior therapy. Venetoclax, a selective oral inhibitor of BCL-2 is a novel agent that shows promise as a therapeutic agent.

AIMS

The objective of this systematic review is to address how the use of venetoclax, alone or as a combination regimen, contributed to the treatment of patients with t(11:14) positive relapsed/refractory multiple myeloma (RRMM).

DATA SOURCES

This systematic review was conducted in accordance to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and was done on 5th June 2022. A literature search was conducted on PubMed and Scopus, 145 articles were screened and 10 studies were included. Risk of bias assessment was performed using the Methodological Index for Non-Randomized Studies (MINORS) criteria.

DATA SUMMARY

Across the studies reviewed, a total of 311 patients were identified with t(11;14) positive RRMM. The overall response rate achieved ranged between 33% and 95.5%. Furthermore, the use of venetoclax has exhibited a favorable adverse effect profile. Side effects included hematological side effects, nausea, vomiting, and diarrhea.

CONCLUSION

Venetoclax demonstrates promising results. When given with drugs like dexamethasone, daratumumab and carfilzomib, a synergistic effect is seen in treating translocation (11:14) positive relapsed/refractory MM. The use of venetoclax in clinical practice can potentially improve outcomes and quality of life in RRMM patients, and future research should continue to explore this promising treatment option.

Integrated epigenetic and transcriptional single-cell analysis of t(11;14) multiple myeloma and its BCL2 dependency

ABSTRACT

The translocation t(11;14) occurs in 20% of patients with multiple myeloma (MM) and results in the upregulation of CCND1. Nearly two-thirds of t(11;14) MM cells are BCL2 primed and highly responsive to the oral BCL2 inhibitor venetoclax. Although it is evident that this unique sensitivity to venetoclax depends on the Bcl-2 homology domain 3- proapoptotic protein priming of BCL2, the biology underlying t(11;14) MM dependency on BCL2 is poorly defined. Importantly, the epigenetic regulation of t(11;14) transcriptomes and its impact on gene regulation and clinical response to venetoclax remain elusive. In this study, by integrating assay for transposase-accessible chromatin by sequencing (ATAC-seq) and RNA-seq at the single-cell level in primary MM samples, we have defined the epigenetic regulome and transcriptome associated with t(11;14) MM. A B-cell-like epigenetic signature was enriched in t(11;14) MM, confirming its phylogeny link to B-cell rather than plasma cell biology. Of note, a loss of a B-cell-like epigenetic signature with a gain of canonical plasma cell transcription factors was observed at the time of resistance to venetoclax. In addition, MCL1 and BCL2L1 copy number gains and structural rearrangements were linked to venetoclax resistance in patients with t(11;14) MM. To date, this is the first study in which both single-cell (sc) ATAC-seq and scRNA-seq analysis are integrated into primary MM cells to obtain a deeper resolution of the epigenetic regulome and transcriptome associated with t(11;14) MM biology and venetoclax resistance.

Venetoclax in biomarker-selected multiple myeloma patients: Impact of exposure on clinical efficacy and safety

Venetoclax, a potent BCL-2 inhibitor, is currently under development for treatment of t(11;14) Multiple myeloma (MM). The objective of this research was to investigate the exposure-response relationships of venetoclax for a phase 1/2 study evaluating venetoclax monotherapy or in combination with dexamethasone in relapsed or refractory MM. A total of 117 patients receiving venetoclax at 300, 600, 800, 900, or 1200 mg were included in the analysis. The impact of venetoclax exposures on efficacy (objective response rate [ORR], progression-free survival [PFS] and overall survival [OS]) as well as safety (treatment-emergent adverse effects (grade ≥3) of neutropenia, infection, and any grade of serious treatment-emergent adverse effects) was evaluated. In the t(11;14)-positive subpopulation, venetoclax exposure relationships to PFS and OS indicated a trend of longer PFS and OS with higher exposures. Moreover, logistic regression analyses for clinical response (ORR and ≥VGPR rate) demonstrated a statistically significant (p < 0.05) relationship with exposure. Evaluation of the exposure-safety relationships demonstrated a lack of a relationship between venetoclax exposures (AUCavg ) and grade ≥3 infections, grade ≥3 neutropenia, grade ≥3 treatment-emergent adverse events or any grade serious treatment-emergent adverse events. These findings support further study of venetoclax at 800 mg QD dose in combination with dexamethasone in the t(11;14)-positive patient population where increased efficacy was observed without an increase in safety events.Clinical Trial: NCT01794520 registered 20 February 2013.

The Role of t(11;14) in Tailoring Treatment Decisions in Multiple Myeloma

Multiple myeloma (MM) represents a hematological neoplasia with an uncontrolled proliferation of malignant plasma cells and complex cytogenetic abnormalities. t(11;14) has emerged as a crucial genetic aberration and is one of the most common primary translocations in MM. Patients harboring t(11;14) represent a distinctive subgroup with a clinical profile that differs from t(11;14)-negative MM risk categories. One of the key features linked with t(11;14) is the BCL2 dependency, indicating vulnerability to BCL2 inhibition. BCL2 inhibitors, such as venetoclax, demonstrated impressive efficacy alone or in combination with other anti-myeloma drugs in patients with RRMM accompanied by t(11;14) and BCL2 overexpression. Therefore, t(11;14) plays a key role in both risk stratification and informed decision making towards a tailored therapy. In this review, we highlight the biology of t(11;14) in MM cells, summarize the current evolving role of t(11;14) in the era of novel agents and novel targeted therapies, illuminate current efficacy and safety data of BCL2-based treatment options and explore the future prospects of individualized precision medicine for this special subgroup of patients with MM.

Clinical and cytogenetic characteristics of primary and secondary plasma cell leukemia under the new IMWG definition criteria: a retrospective study

BACKGROUND

Plasma cell leukemia (PCL) is a rare and aggressive plasma cell disorder, exhibiting a more unfavorable prognosis than multiple myeloma. PCL is classified into pPCL and sPCL. Recently, the IMWG has recommended new PCL definition criteria, which require the presence of ≥5% circulating plasma cells in peripheral blood smears. Due to its low incidence, research on pPCL and sPCL is limited.

METHODS

We conducted a retrospective study and analyzed clinical and cytogenetic data of pPCL and sPCL patients. Overall survival (OS) and progression-free survival (PFS) were assessed by the Kaplan-Meier method, and survival distributions were compared using the log-rank test.

RESULTS

This is a small cohort comprising 23 pPCL and 9 sPCL patients. Notably, sPCL patients showed a higher incidence of extramedullary infiltration and a higher percentage of bone marrow plasma cells (p = 0.015 and 0.025, respectively). Although no significant difference was found between the two groups in OS and PFS, a trend emerged suggesting a superior survival outcome for pPCL patients, with a higher cumulative 1-year PFS rate (38.3% vs. 13.3%) and a lower early mortality rate (mortality rate at 3 months: 15% vs. 33%). We also suggested that pPCL patients carrying t(11;14) may have a longer median survival time than individuals with other cytogenetic abnormalities, but this was not confirmed due to the small sample size.

CONCLUSION

Our study revealed clinical and cytogenetic features of pPCL and sPCL patients according to the new diagnostic criteria. The findings suggested a generally better prognosis for pPCL than sPCL and the likelihood of t(11;14) translocation acting as a favorable prognostic factor in pPCL. It is important to note that our study had a limited sample size, which may lead to bias. We hope well-designed studies can be conducted to provide more results.

Efficacy and safety of Venetoclax-based regimens in relapsed or refractory multiple myeloma: a systematic review and meta-analysis of prospective clinical trials

BACKGROUND

Multiple myeloma (MM) is an incurable malignancy. Venetoclax (VEN) shows a meaningful effect in MM patients who are relapsed or refractory (RR) to previous standard therapies.

OBJECTIVE

This study aimed to assess the efficacy and safety of VEN-based treatments in RR MM patients.

MATERIALS AND METHODS

Comprehensive studies were searched in PubMed, Embase, Web of Science and Cochrane library. Efficacy was assessed by overall response rate (ORR), strict complete response rate (sCR), complete response rate (CR), very good partial response rate (VGPR) and partial response rate (PR).

RESULTS

Seven studies containing 482 subjests were included. The pooled ORR, ≥ CR (sCR + CR), VGPR and PR were 68% (51%-85%), 24% (13%-35%), 25% (17%-34%) and 17% (11%-24%) respectively. Multi-drug treatments were superior to VEN ± dexamethasone (Dex) treatments in ORR (82% vs 42%, p = .003) and ≥ CR (36% vs 7%, p < 0.00001). Subgroup analysis indicated patients achieve higher ORR who harboring t(11;14) translocation or containing high BCL-2 expression.

CONCLUSIONS

VEN-containing regimens could be suggested as effective and safe treatments to RR MM patients with t(11;14) or high BCL-2 levels.

Effective venetoclax-based treatment in relapsed/refractory multiple myeloma patients with translocation t(6;14)

Introduction: The selective Bcl-2 inhibitor venetoclax has shown promising therapeutic potential in multiple myeloma, particularly in cases associated with t(11;14) IGH::CCND1 translocation. However, the efficacy of venetoclax in myeloma patients with the t(6;14) IGH::CCND3 translocation remains less investigated. Methods: In this study, we conducted a retrospective analysis to investigate the efficacy of venetoclax-based therapy in relapsed/refractory myeloma patients with t(6;14) translocation. The treatment courses of three patients, that included previous therapies and responses to venetoclax, were assessed. Clinical data, laboratory results, and adverse events were analyzed to evaluate treatment outcomes. Results: Our findings demonstrated remarkable therapeutic responses in three consecutive patients with t(6;14) translocation-associated myeloma who received venetoclax-based therapy. Patient 1, a lenalidomide-bortezomib-daratumumab and alkylator treatment refractory patient, achieved sustained stringent complete remission (sCR) after combining carfilzomib-dexamethasone with venetoclax, which was his best response ever. Similarly, Patient 2, refractory to frontline bortezomib-thalidomide-dexamethasone therapy, attained CR following a transition to bortezomib-dexamethason-venetoclax treatment. Patient 3, who was immunomodulatory (IMID)-intolerant, showed a highly favorable response to venetoclax-dexamethasone therapy after his first relapse following autologous stem cell transplantation. No significant adverse effects were observed in any of the patients. Discussion: Our study provides compelling preliminary evidence for the efficacy of venetoclax in t(6;14) translocation-associated myeloma. The outcomes observed in our patients suggest that venetoclax-based therapy holds substantial promise as an effective treatment option for this specific genetic subgroup. Furthermore, the similarities in treatment response between t(11;14) and t(6;14) translocation subgroups highlight the importance of personalized approaches targeting specific genetic abnormalities to optimize therapeutic outcomes.

Efficacy and safety of venetoclax in patients with relapsed/refractory multiple myeloma: a meta-analysis

BACKGROUND

Venetoclax is clinically active in treating relapsed/refractory multiple myeloma (RRMM). This study evaluated the efficacy and safety of venetoclax or venetoclax with other agents in treating RRMM.

METHODS

PubMed, Web of Science, Embase, and Cochrane Library were comprehensively searched. We included studies investigating the efficacy and safety of venetoclax or venetoclax with other agents in treating RRMM. Overall response rates (ORR), stringent complete response rates (sCR), complete response rates (CR), very good partial response rates (VGPR), partial response rates (PR), stable disease (SD), progressive disease (PD) and adverse events were synthesized using either a random-effects model or a fixed-effects model.

RESULTS

A total of 7 clinical trials with 482 patients with RRMM were included. Concerning venetoclax with other agents, the pooled ORR, sCR, CR, VGPR, PR, SD, and PD were 0.76 (95% CIs: 0.62, 0.87), 0.11 (95% CIs: 0.04, 0.21), 0.18 (95% CIs: 0.11, 0.26), 0.16 (95% CIs: 0.12, 0.25), 0.29 (95% CIs: 0.25, 0.34), 0.07 (95% CIs: 0.05, 0.10), and 0.11 (95% CIs: 0.04, 0.23). The overall rate of adverse events ≥ Grade 3 was 0.84 (95% CIs: 0.77, 0.91). The most common non-hematologic adverse events were nausea, diarrhea, fatigue, back pain, and vomiting; hematologic adverse events included thrombocytopenia, neutropenia, anemia, leukopenia, and lymphopenia.

CONCLUSIONS

This study indicates that venetoclax alone or in combination with other agents reveals favorable treatment responses and acceptable adverse events in treating RRMM.

Current Advances and Future Strategies for BCL-2 Inhibitors: Potent Weapons against Cancers

Targeting the intrinsic apoptotic pathway regulated by B-cell lymphoma-2 (BCL-2) antiapoptotic proteins can overcome the evasion of apoptosis in cancer cells. BCL-2 inhibitors have evolved into an important means of treating cancers by inducing tumor cell apoptosis. As the most extensively investigated BCL-2 inhibitor, venetoclax is highly selective for BCL-2 and can effectively inhibit tumor survival. Its emergence and development have significantly influenced the therapeutic landscape of hematological malignancies, especially in chronic lymphocytic leukemia and acute myeloid leukemia, in which it has been clearly incorporated into the recommended treatment regimens. In addition, the considerable efficacy of venetoclax in combination with other agents has been demonstrated in relapsed and refractory multiple myeloma and certain lymphomas. Although venetoclax plays a prominent antitumor role in preclinical experiments and clinical trials, large individual differences in treatment outcomes have been characterized in real-world patient populations, and reduced drug sensitivity will lead to disease recurrence or progression. The therapeutic efficacy may vary widely in patients with different molecular characteristics, and key genetic mutations potentially result in differential sensitivities to venetoclax. The identification and validation of more novel biomarkers are required to accurately predict the effectiveness of BCL-2 inhibition therapy. Furthermore, we summarize the recent research progress relating to the use of BCL-2 inhibitors in solid tumor treatment and demonstrate that a wealth of preclinical models have shown promising results through combination therapies. The applications of venetoclax in solid tumors warrant further clinical investigation to define its prospects.

Infections following bispecific antibodies in myeloma: a systematic review and meta-analysis

Bispecific antibodies, a novel immunotherapy with promising efficacy against multiple myeloma, form immune synapses between T-cell surface marker CD3 and malignant cell markers, including B-cell maturation antigen (BCMA), FcRH5, and G protein-coupled receptor GPRC5D. These bispecific antibodies so effectively deplete plasma cells (and to some extent T-cells) that patients are at increased risk of developing infections. A systematic review and meta-analysis of infections in published studies of patients with myeloma treated with bispecific antibodies was conducted to better characterize the infection risks. A literature search used MEDLINE, EMBASE, and Cochrane to identify relevant studies between inception and February 10, 2023, including major conference presentations. Phase 1b-3 clinical trials and observational studies were included. Sixteen clinical trials comprising 1666 patients were included. Median follow-up was 7.6 months and 38% of the cohort had penta-drug refractory disease. Pooled prevalence of all-grade infections was 56%, whereas the prevalence of grade ≥3 infections was 24%. Patients who were treated with BCMA-targeted bispecifics had significantly higher rates of grade ≥3 infections than non-BCMA bispecifics (25% vs 20%). Similarly, patients treated with bispecifics in combination with other agents had significantly higher rate of all-grade infection than those receiving monotherapy (71% vs 52%). In observational studies (n = 293), excluded from the primary analysis to ensure no overlap with patients in clinical trials, several infections classically associated with T-cell depletion were identified. This systematic review identifies BCMA-targeted bispecifics and bispecific combination therapy as having higher infection risk, requiring vigilant infection screening and prophylaxis strategies.

The prognostic impact of t(11;14) in multiple myeloma: A real-world analysis from the Australian Lymphoma Leukaemia Group (ALLG) and the Australian Myeloma and Related Diseases Registry (MRDR)

The prognostic impact of t(11;14) in multiple myeloma (MM) needs to be better understood to inform future treatment decisions. The Australian Lymphoma Leukaemia Group embarked on a retrospective, observational cohort study using real-world data to interrogate treatment patterns and outcomes in 74 MM patients with t(11;14) [t(11;14)-MM] diagnosed over 10 years. This was compared to 159 and 111 MM patients with high-risk IgH translocations (IgH HR-MM) and hyperdiploidy (Hyperdiploid-MM), respectively, from the Australian Myeloma and Related Diseases Registry. No appreciable differences in age, gender, ISS, LDH levels, 1q21 or del(17p) status, or treatment patterns were observed between groups. Median PFS-1 was not different between groups but both t(11;14)-MM and IgH HR-MM had an inferior PFS-2 vs. Hyperdiploid-MM: median PFS-2 8.2 months, 10.0 months, and 19.8 months (p = 0.002), respectively. The 3-year OS were 69%, 71%, and 82% (p = 0.026), respectively. In the t(11;14)-MM group, gain or amplification of 1q21 at diagnosis predicted for poorer OS (HR 3.46, p = 0.002). Eleven patients had received venetoclax with 45% achieving better than a very good partial response. Results suggest that t(11;14) MM may confer an unfavorable risk profile and that the use of targeted therapies such as venetoclax earlier in the treatment algorithm should be explored.

Management of Relapsed-Refractory Multiple Myeloma in the Era of Advanced Therapies: Evidence-Based Recommendations for Routine Clinical Practice

Multiple myeloma (MM) is the second most common hematologic malignancy in adults worldwide. Over the past few years, major therapeutic advances have improved progression-free and overall survival, as well as quality of life. Despite this recent progress, MM remains incurable in the vast majority of cases. Patients eventually relapse and become refractory to multiple drug classes, making long-term management challenging. In this review, we will focus on the treatment paradigm of relapsed/refractory MM (RRMM) in the era of advanced therapies emphasizing the available novel modalities that have recently been incorporated into routine practice, such as chimeric antigen receptor T-cell therapy, bispecific antibodies, and other promising approaches. We will also discuss major factors that influence the selection of appropriate drug combinations or cellular therapies, such as relapse characteristics, and other disease and patient related parameters. Our goal is to provide insight into the currently available and experimental therapies for RRMM in an effort to guide the therapeutic decision-making process.

Multiple myeloma with t(11;14): impact of novel agents on outcome

Multiple myeloma (MM) patients with t(11;14) present unique biological features and their prognosis is not well established. We report a retrospective study of 591 MM patients, 17.3% of whom had t(11;14). It was designed to determine the prognostic impact of this abnormality and the effect of novel agents on the response and outcomes. Three groups were established based on their cytogenetics: (1) t(11;14); (2) high-risk chromosomal abnormalities; and (3) standard risk (SR). After 80.1 months (1.2-273.8 months) of follow-up, no differences were observed in overall survival (OS) between the t(11;14) and SR groups (75.8 vs. 87.2 months; P = 0.438). Treatment of MM t(11;14) with novel agents did not improve their overall response rate (ORR) or complete response (CR) compared with those who received conventional therapy (ORR: 87.2 vs. 79.5%, P = 0.336; CR: 23.4 vs. 12.8%, P = 0.215). This effect translated into a similar PFS (39.6 vs. 30.0 months; P = 0.450) and OS (107.6 vs. 75.7 months; P = 0.175). In summary, MM t(11;14) patients did not benefit from the introduction of novel agents as much as SR patients did, indicating that other therapies are needed to improve their outcomes.

Cardiovascular Toxicity of Proteasome Inhibitors: Underlying Mechanisms and Management Strategies: JACC: CardioOncology State-of-the-Art Review

Proteasome inhibitors (PIs) are the backbone of combination treatments for patients with multiple myeloma and AL amyloidosis, while also indicated in Waldenström's macroglobulinemia and other malignancies. PIs act on proteasome peptidases, causing proteome instability due to accumulating aggregated, unfolded, and/or damaged polypeptides; sustained proteome instability then induces cell cycle arrest and/or apoptosis. Carfilzomib, an intravenous irreversible PI, exhibits a more severe cardiovascular toxicity profile as compared with the orally administered ixazomib or intravenous reversible PI such as bortezomib. Cardiovascular toxicity includes heart failure, hypertension, arrhythmias, and acute coronary syndromes. Because PIs are critical components of the treatment of hematological malignancies and amyloidosis, managing their cardiovascular toxicity involves identifying patients at risk, diagnosing toxicity early at the preclinical level, and offering cardioprotection if needed. Future research is required to elucidate underlying mechanisms, improve risk stratification, define the optimal management strategy, and develop new PIs with safe cardiovascular profiles.

Recent Advances in the Applications of Small Molecules in the Treatment of Multiple Myeloma

Therapy for multiple myeloma (MM), a hematologic neoplasm of plasma cells, has undergone remarkable changes over the past 25 years. Small molecules (molecular weight of less than one kDa), together with newer immunotherapies that include monoclonal antibodies, antibody-drug conjugates, and most recently, chimeric antigen receptor (CAR) T-cells, have combined to double the disease's five-year survival rate to over 50% during the past few decades. Despite these advances, the disease is still considered incurable, and its treatment continues to pose substantial challenges, since therapeutic refractoriness and patient relapse are exceedingly common. This review focuses on the current pipeline, along with the contemporary roles and future prospects for small molecules in MM therapy. While small molecules offer prospective benefits in terms of oral bioavailability, cellular penetration, simplicity of preparation, and improved cost-benefit considerations, they also pose problems of toxicity due to off-target effects. Highlighted in the discussion are recent developments in the applications of alkylating agents, immunomodulators, proteasome inhibitors, apoptosis inducers, kinesin spindle protein inhibitors, blockers of nuclear transport, and drugs that affect various kinases involved in intracellular signaling pathways. Molecular and cellular targets are described for each class of agents in relation to their roles as drivers of MM.

Efficacy and safety of venetoclax-based regimens for the treatment of relapsed/refractory multiple myeloma: a systemic review and meta-analysis

BACKGROUND

Patients with relapsed/refractory multiple myeloma (RRMM) usually have dismal prognostic outcomes. Venetoclax, a selective inhibitor of antiapoptotic protein B-cell lymphoma-2 (BCL-2), demonstrates antimyeloma activity in plasma cells with t(11;14) or high BCL-2 expression.

OBJECTIVES

This meta-analysis aimed to investigate the efficacy and safety of venetoclax-based therapy in RRMM.

DESIGN

This is a meta-analysis study.

DATA SOURCES AND METHODS

PubMed, Embase, and Cochrane were searched for studies published up to 20 December 2021. Overall response rate (ORR), rate of very good partial response or better (≧VGPR), and complete response (CR) rate were pooled with the random-effects model. Safety was evaluated by the incidences of grade ≧3 adverse events. Subgroup analysis and meta-regression were performed to identify the causes of heterogeneities. All the analyses were conducted by STATA 15.0 software.

RESULTS

A total of 14 studies with 713 patients were included for analysis. The pooled ORR, rate of ≧VGPR, and CR for all patients were 59% [95% confidence interval (CI) = 45-71%], 38% (95% CI = 26-51%), and 17% (95% CI = 10-26%), respectively. The median progression-free survival (PFS) ranged from 2.0 months to not reached (NR), and the median overall survival (OS) ranged from 12.0 months to NR. Meta-regression showed that patients treated with more drugs combined or less heavily pretreated had higher response rates. Patients with t(11;14) had superior ORR [relative risk (RR) = 1.47, 95% CI = 1.05-2.07], ≧VGPR (RR = 1.71, 95% CI = 1.12-2.60), CR (RR = 1.86, 95% CI = 1.34-2.57), PFS [hazard ratio (HR) = 0.47, 95% CI = 0.30-0.65], and OS (HR = 0.30, 95% CI = 0.08-0.52) compared with patients without t(11;14). Most grade ≧3 adverse events were hematologic, gastrointestinal, and infectious related and were manageable.

CONCLUSION

Venetoclax-based therapy is an effective and safe option for RRMM patients, especially those with t(11;14).

Bone marrow microenvironment- induced regulation of Bcl-2 family members in multiple myeloma (MM): Therapeutic implications

In Multiple Myeloma (MM) the finely tuned homeostasis of the bone marrow (BM) microenvironment is disrupted. Evasion of programmed cell death (apoptosis) represents a hallmark of cancer. Besides genetic aberrations, the supportive and protective MM BM milieu, which is constituted by cytokines and growth factors, intercellular and cell: extracellular matrix (ECM) interactions and exosomes, in particular, plays a key role in the abundance of pro-survival members of the Bcl-2 family (i.e., Mcl-1, Bcl-2, and Bcl-xL) in tumor cells. Moreover, microenvironmental cues have also an impact on stability- regulating post-translational modifications of anti-apoptotic proteins including de/phosphorylation, polyubiquitination; on their intracellular binding affinities, and localization. Advances of our molecular knowledge on the escape of cancer cells from apoptosis have informed the development of a new class of small molecules that mimic the action of BH3-only proteins. Indeed, approaches to directly target anti-apoptotic Bcl-2 family members are among today's most promising therapeutic strategies and BH3-mimetics (i.e., venetoclax) are currently revolutionizing not only the treatment of CLL and AML, but also hold great therapeutic promise in MM. Furthermore, approaches that activate apoptotic pathways indirectly via modification of the tumor microenvironment have already entered clinical practice. The present review article will summarize our up-to-date knowledge on molecular mechanisms by which the MM BM microenvironment, cytokines, and growth factors in particular, mediates tumor cell evasion from apoptosis. Moreover, it will discuss some of the most promising science- derived therapeutic strategies to overcome Bcl-2- mediated tumor cell survival in order to further improve MM patient outcome.

Small molecule inhibitors targeting the cancers

Compared with traditional therapies, targeted therapy has merits in selectivity, efficacy, and tolerability. Small molecule inhibitors are one of the primary targeted therapies for cancer. Due to their advantages in a wide range of targets, convenient medication, and the ability to penetrate into the central nervous system, many efforts have been devoted to developing more small molecule inhibitors. To date, 88 small molecule inhibitors have been approved by the United States Food and Drug Administration to treat cancers. Despite remarkable progress, small molecule inhibitors in cancer treatment still face many obstacles, such as low response rate, short duration of response, toxicity, biomarkers, and resistance. To better promote the development of small molecule inhibitors targeting cancers, we comprehensively reviewed small molecule inhibitors involved in all the approved agents and pivotal drug candidates in clinical trials arranged by the signaling pathways and the classification of small molecule inhibitors. We discussed lessons learned from the development of these agents, the proper strategies to overcome resistance arising from different mechanisms, and combination therapies concerned with small molecule inhibitors. Through our review, we hoped to provide insights and perspectives for the research and development of small molecule inhibitors in cancer treatment.

Management of Relapsed and Refractory Multiple Myeloma: Recent advances

Multiple myeloma (MM) accounts for ∼10% of total hematologic malignancies worldwide. In India, the incidence of MM has increased two-fold with marked heterogeneity. Significant improvements in terms of clinical outcomes have been observed in the management of MM in recent years. However, most patients develop a disease relapse with the first or subsequent treatments. A combination of immunomodulatory drugs (thalidomide and lenalidomide) and proteasome inhibitors (PIs; bortezomib) has been the mainstay for the therapeutic management of relapsed/refractory multiple myeloma (RRMM). This review highlights the management of RRMM with newer agents such as belantamab, carfilzomib, daratumumab, elotuzumab, ixazomib, mafadotin, selinexor, panobinostat, and venetoclax, with more focus on PIs. As a single agent and in combination with other drugs including dexamethasone and carfilzomib has been studied extensively and approved by the United States, European Union, and India. Clinical trials of these newer agents, either alone or in combination, for the treatment of RRMM in Western countries indicate survival, improved outcomes, and overall well-being. However, evidence in Indian patients is evolving from ongoing studies on carfilzomib and daratumumab, which will ascertain their efficacy and safety. Currently, several guidelines recommend carfilzomib-based, daratumumab-based, and panobinostat-based regimens in RRMM patients. Currently, with more accessible generic versions of these drugs, more Indian patients may attain survival benefits and improved quality of life.

Advances in the molecular characterization of multiple myeloma and mechanism of therapeutic resistance

Recent insight in the genomic landscape of newly diagnosed multiple myeloma (NDMM) and its precursor conditions, monoclonal gammopathy of uncertain significance (MGUS), and smoldering myeloma have allowed the identification of patients with precursor conditions with a high risk of progression. These cases with "progressor" MGUS/SMM have a higher average mutation burden, have higher rates of mutations in specific genes such as MAPK, DNA repair, MYC, DIS3, and are enriched for specific mutational signatures when compared to non-progressors and are comparable to those found in NDMM. The highly preserved clonal heterogeneity seen upon progression of SMM, combined with the importance of these early variables, suggests that the identification of progressors based on these findings could complement and enhance the currently available clinical models based on tumor burden. Mechanisms leading to relapse/refractory multiple myeloma (RRMM) are of clinical interest given worse overall survival in this population. An Increased mutational burden is seen in patients with RRMM when compared to NDMM, however, there is evidence of branching evolution with many of these mutations being present at the subclonal level. Likewise, alterations in proteins associated with proteosome inhibitor and immunomodulatory drugs activity could partially explain clinical resistance to these agents. Evidence of chromosomal events leading to copy number changes is seen, with the presence of TP53 deletion, mutation, or a combination of both being present in many cases. Additional chromosomal events such as 1q gain and amplification may also interact and lead to resistance.

Targeting CD38 in Neoplasms and Non-Cancer Diseases

Simple Summary

CD38 remains an interesting target for anticancer therapy. Its relatively high abundance in neoplasms and crucial impact on NAD+/cADPR metabolism and the activity of T cells allows for changing the immune response in autoimmune diseases, neoplasms, and finally the induction of cell death. Antibody-dependent cell cytotoxicity is responsible for cell death induced by targeting the tumor with anti-CD38 antibodies, such as daratumumab. A wide range of laboratory experiments and clinical trials show an especially promising role of anti-CD38 therapy against multiple myeloma, NK cell lymphomas, and CD19- B-cell malignancies. More studies are required to include more diseases in the therapeutic protocols involving the modulation of CD38 activity.

Abstract

CD38 is a myeloid antigen present both on the cell membrane and in the intracellular compartment of the cell. Its occurrence is often enhanced in cancer cells, thus making it a potential target in anticancer therapy. Daratumumab and isatuximab already received FDA approval, and novel agents such as MOR202, TAK079 and TNB-738 undergo clinical trials. Also, novel therapeutics such as SAR442085 aim to outrank the older antibodies against CD38. Multiple myeloma and immunoglobulin light-chain amyloidosis may be effectively treated with anti-CD38 immunotherapy. Its role in other hematological malignancies is also important concerning both diagnostic process and potential treatment in the future. Aside from the hematological malignancies, CD38 remains a potential target in gastrointestinal, neurological and pulmonary system disorders. Due to the strong interaction of CD38 with TCR and CD16 on T cells, it may also serve as the biomarker in transplant rejection in renal transplant patients. Besides, CD38 finds its role outside oncology in systemic lupus erythematosus and collagen-induced arthritis. CD38 plays an important role in viral infections, including AIDS and COVID-19. Most of the undergoing clinical trials focus on the use of anti-CD38 antibodies in the therapy of multiple myeloma, CD19- B-cell malignancies, and NK cell lymphomas. This review focuses on targeting CD38 in cancer and non-cancerous diseases using antibodies, cell-based therapies and CD38 inhibitors. We also provide a summary of current clinical trials targeting CD38.

Exploring the current molecular landscape and management of multiple myeloma patients with the t(11;14) translocation

Multiple myeloma (MM) is a genetically complex disease. The key myeloma-initiating genetic events are hyperdiploidy and translocations involving the immunoglobulin heavy chain (IgH) enhancer on chromosome 14, which leads to the activation of oncogenes (e.g., CCND1, CCND3, MAF, and MMSET). The t(11;14) translocation is the most common in MM (15%–20%) and results in cyclin D1 (CCND1) upregulation, which leads to kinase activation and tumor cell proliferation. Notably, t(11;14) occurs at a higher rate in patients with plasma cell leukemia (40%) and light chain amyloidosis (50%). Patients with myeloma who harbor the t(11;14) translocation have high levels of the anti-apoptotic protein B-cell lymphoma 2 (BCL2). Multiple studies demonstrated that the presence of t(11;14) was predictive of BCL2 dependency, suggesting that BCL2 could be a target in this subtype of myeloma. Venetoclax, an oral BCL2 inhibitor, has shown remarkable activity in treating relapsed/refractory MM patients with t(11;14) and BCL2 overexpression, either as monotherapy or in combination with other anti-myeloma agents. In this review, we describe the molecular defects associated with the t(11;14), bring into question the standard cytogenetic risk of myeloma patients harboring t(11;14), summarize current efficacy and safety data of targeted venetoclax-based therapies, and discuss the future of individualized or precision medicine for this unique myeloma subgroup, which will guide optimal treatment.

Toxicity management strategies for next-generation novel therapeutics in multiple myeloma

The therapeutic options available for patients with multiple myeloma have greatly expanded over the past decade and incorporating these novel agents into routine clinical practice has significantly improved outcomes. The next generation of therapeutics is available for relapsed and refractory patients either as standard of care or in clinical trial, and these drugs represent a generational paradigm shift. Patients now have access to a multitude of novel immunotherapeutics, including monoclonal antibodies, an antibody-drug conjugate, chimeric antigen receptor T-cells (CAR-T), and bispecific T-cell redirecting antibodies, and novel oral therapies including selinexor (selective inhibitor of nuclear export) and venetoclax (bcl-2 inhibitor). While these drugs have the potential to be highly efficacious in certain subsets of patients when used as single agents or in combination regimens, they are each associated with unique toxicity profiles. It is imperative to understand these potential adverse events to ensure patient safety. Appropriate supportive care management is paramount to maximize drug exposure and therapeutic efficacy. The following review focuses its discussion on drugs and combination regimens that are currently FDA-approved and those that continue to be investigated in clinical trials, highlights the clinically relevant toxicity profiles for each of the different agents, and provides practical considerations for the treatment team.

Multiple myeloma with t(11;14): unique biology and evolving landscape

Multiple myeloma is characterized by heterogeneity in clinical presentation, response to treatment, and importantly, patient outcomes. The translocation of chromosomes 11 and 14 [t(11;14)(q13;32)], hereafter referred to as t(11;14), is the most common primary translocation event in multiple myeloma, occurring in approximately 16%-24% of patients. Multiple myeloma harboring t(11;14) represents a unique disease subset as t(11;14)-positive myeloma cells exhibit biological features that are distinct from t(11;14)-negative myeloma cells, including overexpression of cyclin D1, higher levels of the antiapoptotic protein BCL-2, and the frequent expression of the B-cell lineage protein CD20. Additionally, t(11;14) is associated with less common clinical features, such as immunoglobulin M and light chain disease. With the evolution of the treatment landscape, the prognostic significance of t(11;14) multiple myeloma remains debatable. However, it is clear that t(11;14) multiple myeloma represents a distinct subset and a rare opportunity for targeted therapy with BCL-2 inhibition. In this review, we first describe the underlying biology of t(11;14) multiple myeloma cells, then summarize the body of literature evaluating the prognosis of patients with t(11;14) multiple myeloma, and finally discuss therapeutic implications.

On the continuous (R)evolution of antibody-based and CAR T cell therapies in multiple myeloma: An early 2022 glance into the future

INTRODUCTION

The pace at which the identification of novel therapeutic targets has led to the approval of Multiple Myeloma (MM) agents during the last two decades is nothing more than spectacular. Nevertheless, MM remains an incurable disease. Therefore, there is an urgent need for additional, innovative therapeutics. Immune dysfunction and the tumor-permissive immune bone marrow microenvironment represent hallmarks of MM pathophysiology. Naked monoclonal antibodies directed against SLAMF7 and CD38 already constitute backbones of today's MM therapy. Novel immunotherapeutic modalities including antibody-drug-conjugates (ADC), bispecific antibodies (BsAb) and chimeric-antigen-receptor T cells are on the way to once more revolutionize future MM therapy.

AREAS COVERED

The present review article summarizes the most recent results on MM immunotherapies presented at the 2021 Annual Meeting of the American Society of Hematology; and throws a glance on ongoing preclinical and clinical efforts aiming at further increasing their efficacy, while reducing their toxicity.

EXPERT OPINION

With the approvals of the first-in-class BCMA-targeting ADC (belantamab mafodotin) and two BCMA-targeting CAR T cell products (Ide-cel, Cilta-cel); and the approval of the first-in-class BCMAxCD3 BsAb immediately pending, the era of modern next-generation immunotherapies in MM is continuously evolving. Long-term disease-free survival and potential cure of MM are finally within reach.

Updates in the Use of BCL-2-Family Small Molecule Inhibitors for the Treatment of Relapsed/Refractory Multiple Myeloma

Despite considerable advances in the treatment of multiple myeloma over the past decade, progression of disease is inevitable, and patients ultimately succumb to relapsed and refractory disease. Efficacious therapeutic regimens that target the key biological pathways that are essential for malignant plasma cell survival are necessary in the efforts to improve patient survival outcomes. The Bcl-2 family of proteins comprise oncogenes that promote myeloma cell survival by conferring resistance to apoptosis. These proteins are frequently upregulated in myeloma cells, thus making them attractive therapeutic targets. Several small molecule inhibitors of Bcl-2-family proteins are currently in clinical development for the treatment of relapsed/refractory multiple myeloma. Venetoclax, a Bcl-2-specific inhibitor, has generated the most clinical data and has shown promising results in patients with multiple myeloma harboring the t (11;14) translocation. Venetoclax has shown efficacy when combined with anti-CD38 monoclonal antibodies, immunomodulatory drugs, and proteasome inhibitors. Several other Bcl-2 inhibitors are in clinical development, as are inhibitors of Mcl-1, a Bcl-2-family oncoprotein that is perhaps more critical for myeloma cell survival than Bcl-2. This review will summarize the latest clinical data regarding the clinical development of Bcl-2-family protein inhibitors in the treatment of relapsed/refractory multiple myeloma.

Gaps and opportunities in the treatment of relapsed-refractory multiple myeloma: Consensus recommendations of the NCI Multiple Myeloma Steering Committee

A wide variety of new therapeutic options for Multiple Myeloma (MM) have recently become available, extending progression-free and overall survival for patients in meaningful ways. However, these treatments are not curative, and patients eventually relapse, necessitating decisions on the appropriate choice of treatment(s) for the next phase of the disease. Additionally, an important subset of MM patients will prove to be refractory to the majority of the available treatments, requiring selection of effective therapies from the remaining options. Immunomodulatory agents (IMiDs), proteasome inhibitors, monoclonal antibodies, and alkylating agents are the major classes of MM therapies, with several options in each class. Patients who are refractory to one agent in a class may be responsive to a related compound or to a drug from a different class. However, rules for selection of alternative treatments in these situations are somewhat empirical and later phase clinical trials to inform those choices are ongoing. To address these issues the NCI Multiple Myeloma Steering Committee formed a relapsed/refractory working group to review optimal treatment choices, timing, and sequencing and provide recommendations. Additional issues considered include the role of salvage autologous stem cell transplantation, risk stratification, targeted approaches for genetic subsets of MM, appropriate clinical trial endpoints, and promising investigational agents. This report summarizes the deliberations of the working group and suggests potential avenues of research to improve the precision, timing, and durability of treatments for Myeloma.

Clinical experiences with venetoclax and other pro-apoptotic agents in lymphoid malignancies: lessons from monotherapy and chemotherapy combination

BH3-mimetics are a novel drug class of small molecule inhibitors of BCL2 family proteins which restore apoptosis in malignant cells. The only currently approved BH3-mimetic, the selective BCL2 inhibitor venetoclax, is highly efficacious in chronic lymphocytic leukemia and has rapidly advanced to an approved standard of care in frontline and relapsed disease in combination with anti-CD20 monoclonal antibodies. In this context, tumour lysis syndrome and myelosuppression are the most commonly encountered toxicities and are readily manageable with established protocols. Venetoclax is active in other lymphoid malignancies including several B cell non-Hodgkin lymphomas, acute lymphoblastic leukemia and multiple myeloma, with the highest intrinsic sensitivity observed in mantle cell lymphoma and Waldenstrom macroglobulinemia. Venetoclax combination with standard regimens in follicular lymphoma, multiple myeloma and aggressive B cell neoplasms has shown some promise, but further studies are required to optimize dose and scheduling to mitigate increased myelosuppression and infection risk, and to find validated biomarkers of venetoclax sensitivity. Future research will focus on overcoming venetoclax resistance, targeting other BCL2 family members and the rational design of synergistic combinations.

An update on novel multiple myeloma targets

Introduction: despite therapeutic progress, leading to a significant improvement of outcome, multiple myeloma (MM) remains a difficult to treat hematologic disease due to its biological heterogeneity and clinical complexity.

Areas covered: Treatment of patients refractory and resistant to all classes of agents used in newly diagnosed MM, is becoming a relevant problem for every hematologist. New generation immunotherapies, such as conjugated mAb, bispecific mAbs and CAR-T cells, targeting novel molecules as BCMA, have showed relevant results in very advanced MM. In the same setting, small molecules, such as selinexor and melflufen, also proved to be effective. We are currently waiting for the results of under evaluation personalized therapy, directed against specific gene mutations or signaling pathways, responsible for disease progression.

Expert Opinion: In the near future, many therapeutic strategies will become available for MM and the challenge will be to position each approach in order to cure, maintaining a good quality of life in these patients.

How do we manage t(11;14) plasma cell disorders with venetoclax?

The oral BCL-2 inhibitor venetoclax has demonstrated promising efficacy in patients with t(11;14) plasma cell disorders, both as a single-agent and in combination. However, there was an increased mortality signal in the randomized BELLINI trial that was primarily driven by non-t(11;14) patients. Based on current evidence, venetoclax is included as an option for relapsed/refractory t(11;14) plasma cell dyscrasias in NCCN guidelines and is being widely used in clinical practice. In this review, we aim to critically appraise the current literature and perform case-based illustration of our approach to management of t(11;14) plasma cell disorders with venetoclax.

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.

Treatment patterns and outcomes according to cytogenetic risk stratification in patients with multiple myeloma: a real-world analysis

A clearer understanding of the prognostic implications of t(11;14) in multiple myeloma (MM) is needed to inform current and future therapeutic options. We utilized real-world data from a US database to examine treatment patterns and outcomes in patients by t(11;14) status compared with high- and standard-risk subgroups across different lines of therapy (LoT). This retrospective, observational cohort study used de-identified patient-level information from adults with MM and first-line treatment initiation between January 2011 and January 2020, followed until February 2020. The high-risk cohort comprised patients with high-risk genetic abnormalities per mSMART criteria (including those with co-occurring t(11;14)). Among 6138 eligible patients, 6137, 3160, and 1654 received first-, second-, and third-line treatments, respectively. Of 645 patients who had t(11;14), 69.1% had t(11;14) alone, while 30.9% had co-occurring high-risk abnormalities. Altogether, 1624 and 2544 patients were classified as high- and standard-risk, respectively. In the absence of biomarker-driven therapy, treatment patterns remain similar across LoT in high-risk, t(11;14)+, and standard-risk subgroups. Across all LoT, patient outcomes in the high-risk subgroup were less favorable than those in the t(11;14)+ and standard-risk subgroups. Thus, there is an opportunity for novel therapeutics targeted to t(11;14) and other defined subgroups to personalize MM therapy and optimize patient outcomes.

The Apparent Diffusion Coefficient of Diffusion-Weighted Whole-Body Magnetic Resonance Imaging Affects the Survival of Multiple Myeloma Independently

Background

Diffusion-weighted whole-body MRI (DW-MRI) is increasingly used to evaluate bone diseases of multiple myeloma (MM), but there is lack of quantitative indicator for DW-MRI to reflect the prognosis of MM. Apparent diffusion coefficient (ADC) values in DW-MRI has potential correlations between some indexes of MM, but the influence of ADC on MM survival needs to be further verified.

Methods

A total of 381 newly diagnosed MM patients were enrolled in the study to analyze the effect of ADC values in DW-MRI on progression-free survival (PFS) and overall survival (OS). The Kaplan–Meier method was used to perform univariate survival analysis, and the Cox proportional hazards model was used for multivariate analysis. In addition to the ADC value, genetic and serological indexes were also included.

Results

The survivals were observed in univariate ADC stratification with median PFS of 52.0, 45.0, 34.0, and 26.0 months (the unit of ADC value was 10⁻³ mm²/s; the ADC ranges were ADC < 0.4886, 0.4886 ≤ ADC < 0.6545, 0.6545 ≤ ADC < 0.7750, and ADC ≥ 0.7750; 95% CI, 43.759–62.241, 46.336–53.664, 39.753–46.247, and 27.812–32.188). The OS were 81.0, 61.0, 47.0, and 36.0 months (p < 0.001; 95% CI, 71.356–82.644, 67.630–70.370, 57.031–60.969, and 36.107–43.893). In Cox proportional hazards model, the ADC value was considered to be an independent risk factor affecting PFS and OS of MM (both p < 0.001).

Conclusions

This study supports that ADC in DW-MRI may independently stratify MM patients and better predict their prognosis. The combined use of DW-MRI and other parameters allows more accurate evaluation of MM survival.

Trial Registration

http://www.chictr.org.cn/showproj.aspx?proj=49012, ChiCTR2000029587.

Targeted Venetoclax Therapy in t(11;14) Multiple Myeloma: Real World Data From Seven Hungarian Centers

Despite the introduction of novel agents, multiple myeloma remains incurable for most patients, necessitating further therapeutic options. Venetoclax, a selective BCL-2 inhibitor, had shown promising results in patients with translocation t(11;14), but questions remain open about its optimal use. We have contacted all Hungarian haematology centers for their experience treating t(11;14) myeloma patients with venetoclax. 58 patients were reported. 37 received venetoclax in the relapsed/refractory setting with few or no other therapeutic options available. 21 patients started venetoclax as salvage after failing to achieve satisfactory response to first line therapy. In the relapsed/refractory setting objective response rate (ORR) was 94%, median progression-free survival (PFS) 10.0 months and median overall survival (OS) 14.6 months. In reinduction patients, ORR was 100%, median PFS and OS were not reached. Importantly, we found no adverse effect of high risk features such as deletion 17p or renal failure, in fact renal failure ameliorated in 42% of the cases, including three patients who became dialysis independent. Our study also reports the highest number of plasma cell leukemia cases successfully treated with venetoclax published in literature, with refractory plasma cell leukemia patients achieving a median PFS of 10.0 and a median OS of 12.2 months.

Where We Stand With Precision Therapeutics in Myeloma: Prosperity, Promises, and Pipedreams

Multiple myeloma remains an incurable disease despite numerous novel agents being approved in the last decade. Furthermore, disease behavior and susceptibility to current treatments often vary drastically from patient to patient. To date there are no approved therapies in myeloma that are targeted to specific patient populations based on genomic or immunologic findings. Precision medicine, using biomarkers descriptive of a specific tumor's biology and predictive of response to appropriate agents, may continue to push the field forward by expanding our treatment arsenal while refining our ability to expose patients to only those treatments likely to be efficacious. Extensive research efforts have been carried out in this endeavor including the use of agents targeting Bcl2 and the RAS/MAPK and PI3K/AKT/mTOR pathways. Thus far, clinical trials have yielded occasional successes intermixed with disappointments, reflecting significant hurdles which still remain including the complex crosstalk between oncogenic pathways and the nonlinear genetic development of myeloma, prone to cultivating sub-clones with distinctive mutations. In this review, we explore the landscape of precision therapeutics in multiple myeloma and underscore the degree to which research efforts have produced tangible clinical results.