Daratumumab-based quadruplet therapy for transplant-eligible newly diagnosed multiple myeloma with high cytogenetic risk

In the MASTER study (NCT03224507), daratumumab+carfilzomib/lenalidomide/dexamethasone (D-KRd) demonstrated promising efficacy in transplant-eligible newly diagnosed multiple myeloma (NDMM). In GRIFFIN (NCT02874742), daratumumab+lenalidomide/bortezomib/dexamethasone (D-RVd) improved outcomes for transplant-eligible NDMM. Here, we present a post hoc analysis of patients with high-risk cytogenetic abnormalities (HRCAs; del[17p], t[4;14], t[14;16], t[14;20], or gain/amp[1q21]). Among 123 D-KRd patients, 43.1%, 37.4%, and 19.5% had 0, 1, or ≥2 HRCAs. Among 120 D-RVd patients, 55.8%, 28.3%, and 10.8% had 0, 1, or ≥2 HRCAs. Rates of complete response or better (best on study) for 0, 1, or ≥2 HRCAs were 90.6%, 89.1%, and 70.8% for D-KRd, and 90.9%, 78.8%, and 61.5% for D-RVd. At median follow-up (MASTER, 31.1 months; GRIFFIN, 49.6 months for randomized patients/59.5 months for safety run-in patients), MRD-negativity rates as assessed by next-generation sequencing (10-5) were 80.0%, 86.4%, and 83.3% for 0, 1, or ≥2 HRCAs for D-KRd, and 76.1%, 55.9%, and 61.5% for D-RVd. PFS was similar between studies and superior for 0 or 1 versus ≥2 HRCAs: 36-month PFS rates for D-KRd were 89.9%, 86.2%, and 52.4%, and 96.7%, 90.5%, and 53.5% for D-RVd. These data support the use of daratumumab-containing regimens for transplant-eligible NDMM with HCRAs; however, additional strategies are needed for ultra-high-risk disease (≥2 HRCAs). Video Abstract.

Health-related quality of life in transplant-eligible patients with newly diagnosed multiple myeloma treated with daratumumab, lenalidomide, bortezomib, and dexamethasone: Patient-reported outcomes from GRIFFIN

In the phase 2 GRIFFIN trial (ClinicalTrials.gov identifier: NCT02874742), daratumumab added to lenalidomide, bortezomib, and dexamethasone (D-RVd) improved depth of response and progression-free survival (PFS) versus lenalidomide, bortezomib, and dexamethasone (RVd) alone in transplant-eligible (TE) patients with newly diagnosed multiple myeloma (NDMM). Here, we present patient-reported outcomes (PROs) collected using the European Organisation for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30-item (QLQ-C30), EORTC Quality of Life Questionnaire Multiple Myeloma Module 20-item (QLQ-MY20), and EuroQol 5-Dimension 5-Level (EQ-5D-5L) tools on day 1 of cycles 1, 2, and 3; on day 21 of cycle 4 (end of induction therapy); on day 1 of cycle 5; on day 21 of cycle 6 (end of posttransplant consolidation therapy); and at months 6, 12, 18, and 24 of maintenance therapy. Meaningful improvements from baseline were seen in most of the PRO scales with both treatments after consolidation and were sustained for at least 2 years of maintenance treatment. Large reductions from baseline (~20 points) were especially observed in pain symptoms for both treatment groups, although these were numerically higher for patients receiving D-RVd during the majority of the time points. In addition, improvements in key scales, such as global health status, fatigue symptoms, and physical functioning, were also seen with both D-RVd and RVd. These improvements in health-related quality of life contribute to the totality of evidence supporting the improvement in clinical outcomes such as response rates and PFS with D-RVd in induction, consolidation, and maintenance therapy in TE patients with NDMM.

α-Amino bisphosphonate triazoles serve as GGDPS inhibitors

Depletion of cellular levels of geranylgeranyl diphosphate by inhibition of the enzyme geranylgeranyl diphosphate synthase (GGDPS) is a potential strategy for disruption of protein transport by limiting the geranylgeranylation of the Rab proteins that regulate intracellular trafficking. As such, there is interest in the development of GGDPS inhibitors for the treatment of malignancies characterized by abnormal protein production, including multiple myeloma. Our previous work has explored the structure-function relationship of a series of isoprenoid triazole bisphosphonate-based GGDPS inhibitors, with modifications having impact on enzymatic, cellular and in vivo activities. We have synthesized a new series of α-amino bisphosphonates to understand the impact of modifying the alpha position with a moiety that is potentially linkable to other agents. Bioassays evaluating the enzymatic and cellular activities of these compounds demonstrate that incorporation of the α-amino group affords compounds with GGDPS inhibitory activity which is modulated by isoprenoid tail chain length and olefin stereochemistry. These studies provide further insight into the complexity of the structure-function relationship and will enable future efforts focused on tumor-specific drug delivery.

Post hoc analysis of daratumumab plus lenalidomide, bortezomib and dexamethasone in Black patients from final data of the GRIFFIN study

Due in part to racial disparities and underrepresentation in clinical studies, optimal therapies for Black patients with multiple myeloma remain undefined. This final analysis of GRIFFIN by race showed that the addition of daratumumab (D) to lenalidomide/bortezomib/dexamethasone (RVd) provides clinical benefit among both Black and White transplant-eligible newly diagnosed patients compared with RVd alone. However, Black patients were more likely to discontinue ≥1 drug due to treatment-emergent adverse events. In summary, these findings suggest a benefit of D-RVd front-line therapy among Black and White patients and underscore the importance of equitable treatment access for all patients.

Investigation of the activity of a novel tropolone in osteosarcoma

Osteosarcoma (OS) is a primary malignant bone tumor characterized by frequent metastasis, rapid disease progression, and a high rate of mortality. Treatment options for OS have remained largely unchanged for decades, consisting primarily of cytotoxic chemotherapy and surgery, thus necessitating the urgent need for novel therapies. Tropolones are naturally occurring seven-membered non-benzenoid aromatic compounds that possess antiproliferative effects in a wide array of cancer cell types. MO-OH-Nap is an α-substituted tropolone that has activity as an iron chelator. Here, we demonstrate that MO-OH-Nap activates all three arms of the unfolded protein response (UPR) pathway and induces apoptosis in a panel of human OS cell lines. Co-incubation with ferric chloride or ammonium ferrous sulfate completely prevents the induction of apoptotic and UPR markers in MO-OH-Nap-treated OS cells. MO-OH-Nap upregulates transferrin receptor 1 (TFR1) protein levels, as well as TFR1, divalent metal transporter 1 (DMT1), iron-regulatory proteins (IRP1, IRP2), ferroportin (FPN), and zinc transporter 14 (ZIP14) transcript levels, demonstrating the impact of MO-OH-Nap on iron-homeostasis pathways in OS cells. Furthermore, MO-OH-Nap treatment restricts the migration and invasion of OS cells in vitro. Lastly, metabolomic profiling of MO-OH-Nap-treated OS cells revealed distinct changes in purine and pyrimidine metabolism. Collectively, we demonstrate that MO-OH-Nap-induced cytotoxic effects in OS cells are dependent on the tropolone's ability to alter cellular iron availability and that this agent exploits key metabolic pathways. These studies support further evaluation of MO-OH-Nap as a novel treatment for OS.

Structural Insight into Geranylgeranyl Diphosphate Synthase (GGDPS) for Cancer Therapy

Geranylgeranyl diphosphate synthase (GGDPS), the source of the isoprenoid donor in protein geranylgeranylation reactions, has become an attractive target for anticancer therapy due to the reliance of cancers on geranylgeranylated proteins. Current GGDPS inhibitor development focuses on optimizing the drug-target enzyme interactions of nitrogen-containing bisphosphonate-based drugs. To advance GGDPS inhibitor development, understanding the enzyme structure, active site, and ligand/product interactions is essential. Here we provide a comprehensive structure-focused review of GGDPS. We reviewed available yeast and human GGDPS structures and then used AlphaFold modeling to complete unsolved structural aspects of these models. We delineate the elements of higher-order structure formation, product-substrate binding, the electrostatic surface, and small-molecule inhibitor binding. With the rise of structure-based drug design, the information provided here will serve as a valuable tool for rationally optimizing inhibitor selectivity and effectiveness.

Longitudinal changes in cognitive and physical function and health-related quality of life in older adults with acute myeloid leukemia

INTRODUCTION

Many older adults with acute myeloid leukemia (AML) do not receive chemotherapy because of physicians' and patients' concern for toxicities and functional decline. This highlights the critical and urgent need to generate knowledge of functional changes following new treatments.

MATERIALS AND METHODS

As a part of a pragmatic single-center trial, 59 older adults ≥60 years with AML completed geriatric assessment and health-related quality of life measures before treatment and at one month and three months after chemotherapy initiation. Changes in scores of various geriatric assessment measures were computed by subtracting the baseline score from the one-month and three-month scores for each patient. Established cut-offs were used to determine a clinically meaningful change (improvement or worsening). This study provides results of descriptive exploratory analyses.

RESULTS

Patients experienced significant comorbidity burden and a high prevalence of functional impairments before treatment, with 56% of patients having ≥2 comorbid conditions, 69% having abnormal cognitive function (using Montreal Cognitive Assessment), 69% having impaired objective physical function (using Short Physical Performance Battery), and 64% having a positive depression screen (Patient Health Questionnaire-9). Patients (n = 53) received treatment with predominantly low-intensity chemotherapy; six patients received intensive chemotherapy. Among those who completed some or all of the three-month evaluation (N = 43), from baseline before treatment to three months later, cognitive function improved (38.7%) or remained stable (38.7%), objective physical function improved (51.6%) or remained stable (22.6%), and depression scores improved (9.4%) or remained stable (53.1%). Global health status score and role functioning moderately improved by a score of >16.

DISCUSSION

An exploratory analysis of our phase 2 trial demonstrated improvement or stabilization of cognitive and physical function and depression score at three months in a high proportion of older survivors of AML, despite a high prevalence of frailty and significant comorbidity burden at baseline. These results demonstrate success of treatment in improving cognitive and physical function and depression score, and, if confirmed in larger studies, should encourage oncologists to offer chemotherapy to older adults with AML.

CLINICAL TRIAL REGISTRATION

The study is registered in the ClinicalTrials.gov ID: NCT03226418.

Addition of daratumumab to lenalidomide, bortezomib, and dexamethasone for transplantation-eligible patients with newly diagnosed multiple myeloma (GRIFFIN): final analysis of an open-label, randomised, phase 2 trial

BACKGROUND

Addition of daratumumab to lenalidomide, bortezomib, and dexamethasone (D-RVd) in the GRIFFIN study improved the stringent complete response rate by the end of consolidation in transplantation-eligible patients with newly diagnosed multiple myeloma. Here, we report the findings of the predefined final analysis.

METHODS

GRIFFIN was an open-label, randomised, active-controlled, phase 2 trial done in 35 research centres in the USA. Patients had newly diagnosed multiple myeloma with measurable disease by M protein or free light chain, were aged 18-70 years, had an ECOG performance score of 0-2, and were eligible for autologous haematopoietic stem-cell transplantation (HSCT). Patients were randomly assigned (1:1) to four D-RVd or RVd induction cycles, autologous HSCT, two D-RVd or RVd consolidation cycles, and lenalidomide with or without daratumumab maintenance therapy for 2 years. Patients received 21-day cycles of oral lenalidomide (25 mg on days 1-14), subcutaneous bortezomib (1·3 mg/m2 on days 1, 4, 8, and 11), oral dexamethasone (40 mg weekly) with or without intravenous daratumumab (16 mg/kg weekly, cycles 1-4; day 1, cycles 5-6). Maintenance therapy (28-day cycles) was oral lenalidomide (10 mg on days 1-21) with or without daratumumab (16 mg/kg intravenously every 4 or 8 weeks, or 1800 mg subcutaneously monthly). Patients could continue lenalidomide maintenance after study treatment completion. The primary endpoint was stringent complete response rate by the end of consolidation in the response-evaluable population, and has already been reported. Here we report updated stringent complete response rates and secondary outcomes including progression-free survival and overall survival. The trial is registered with ClinicalTrials.gov (NCT02874742) and ended on April 8, 2022.

FINDINGS

Between Dec 20, 2016, and April 10, 2018, 104 patients were randomly assigned to the D-RVd group and 103 were randomly assigned to the RVd group; most patients were White (85 [82%] in the D-RVd group and 76 [74%] in the RVd group) and male (58 [56%] in the D-RVd group and 60 [58%] in the RVd group). At a median follow-up of 49·6 months (IQR 47·4-52·1), D-RVd improved rates of stringent complete response (67 [67%] of 100] vs 47 [48%] of 98]; odds ratio 2·18 [95% CI 1·22-3·89], p=0·0079), and 4-year progression-free survival was 87·2% (95% CI 77·9-92·8) for D-RVd versus 70·0% (95% CI 55·9-80·3) for RVd, with a hazard ratio (HR) of 0·45 (95% CI 0·21-0·95, p=0·032) for risk of disease progression or death with D-RVd. Median overall survival was not reached for either group (HR 0·90 [95% CI 0·31-2·56], p=0·84). The most common grade 3-4 treatment-emergent adverse events in the D-RVd versus RVd groups were neutropenia (46 [46%] of 99 vs 23 [23%] of 102), lymphopenia (23 [23%] vs 23 [23%]), leukopenia (17 [17%] vs eight [8%]), thrombocytopenia (16 [16%] vs nine [9%]), pneumonia (12 [12%] vs 14 [14%]), and hypophosphataemia (ten [10%] vs 11 [11%]). Serious treatment-emergent adverse events occurred in 46 (46%) of 99 patients in the D-RVd group and in 53 (52%) of 102 patients in the RVd group. One patient in each treatment group reported a treatment-emergent adverse event that resulted in death (bronchopneumonia in the D-RVd group; cause unknown in the RVd group); neither was related to study treatment. No new safety concerns occurred with maintenance therapy.

INTERPRETATION

Addition of daratumumab to RVd improved the depth of response and progression-free survival in transplantation-eligible patients with newly diagnosed multiple myeloma. These results justify further evaluation in phase 3 studies.

FUNDING

Janssen Oncology.

Chimeric Antigen Receptor T-Cell and Bispecific Antibody Therapy in Multiple Myeloma: Moving Into the Future

Historically, the outcomes for individuals with triple-class refractory and penta-drug refractory multiple myeloma (MM) have been poor because of a dearth of effective treatment options. However, the advent of chimeric antigen receptor (CAR) T-cell and T-cell redirecting bispecific antibody (BsAb) therapies has led to unprecedented response rates and durations of response in heavily relapsed/refractory (R/R) populations. Currently, two B-cell maturation antigen (BCMA)-directed CAR T-cell therapies (idecabtagene vicleucel and ciltacabtagene autoleucel) as well as one BCMA/CD3 BsAb (teclistamab) have been approved for late-line (greater than four previous lines) R/R MM in the United States. The purpose of this review is to analyze the recent data for these approved therapies as well as provide an overview of other related CAR T-cell and BsAb therapies under development, including non-BCMA-targeting agents. We review efficacy and safety considerations, with particular focus on cytokine release syndrome, neurotoxicity, and infection risk. The relative merits and limitations of each class of therapy are discussed, as well as the areas of unmet need with respect to optimal sequencing and supportive care measures. We examine the factors that challenge equitable access to these novel therapies across minoritized racial, ethnic, and socioeconomic populations. Although it is evident that CAR T-cell and BsAb therapies will transform treatment paradigms in MM for years to come, significant work remains to identify the optimal utilization of these novel therapies and ensure equitable access.

Ethical Challenges with Multiple Myeloma BCMA Chimeric Antigen Receptor T Cell Slot Allocation: A Multi-Institution Experience

Chimeric antigen receptor T cell (CAR-T) therapies are Food and Drug Administration (FDA)-approved for patients with triple refractory multiple myeloma (MM). Real-world access to CAR-T therapy remains challenging owing to supply chain limitations impacting manufacturing. The goal of this study was to evaluate the extent of this issue and how major centers are handling the challenges of CAR-T manufacturing slot allocation. MM CAR-T physician leaders at each CAR-T treatment center across the United States were surveyed. We received responses from 17 of 20 centers. A median of 1 slot is allocated per month per center, and the median number of patients per center on the waitlist since the FDA's approval of idecabtagene vicleucel is 20 (range, 5 to 100). As a result, patients remain on the waitlist for a median of 6 months (range, 2 to 8 months) prior to leukapheresis. For patient selection, all centers reported using a committee of experienced CAR-T physicians to ensure consistency. To ensure transparency, 15 centers make selection criteria, selection timelines, and priority scores readily available for CAR-T providers. Centers also reported using ethical values for selection: (1) equal treatment: time spent on waiting list (n = 12); (2) priority to the worst-off: limited therapeutic options (n = 14), MM burden (n = 11), high Hematopoietic Cell Transplantation Comorbidity Index (n = 5); (3) maximize benefit: most likely to complete apheresis (n = 13) or infusion (n = 13) or to achieve response (n = 8); and (4) social value: younger patients (n = 3). Maximizing benefit was considered the most important criterion by 10 centers. This study is the first attempt to evaluate existing issues with CAR-T access for patients with MM and the variability and challenges in patient selection. Integrating ethical resource allocation strategies, similar to those described here, into formal institutional policies would help streamline access to CAR-T therapy and protect the needs of both current and future patients and physicians.

Stem Cell Mobilization Yields with Daratumumab- and Lenalidomide-Containing Quadruplet Induction Therapy in Newly Diagnosed Multiple Myeloma: Findings from the MASTER and GRIFFIN Trials

For eligible patients with newly diagnosed multiple myeloma (NDMM), standard of care includes induction therapy followed by autologous stem cell transplantation (ASCT). Daratumumab as monotherapy and in combination treatment is approved across multiple lines of therapy for multiple myeloma (MM), and lenalidomide is an effective and commonly used agent for induction and maintenance therapy in MM. However, there is concern that lenalidomide and daratumumab given as induction therapy might impair mobilization of stem cells for ASCT. Therefore, we assessed stem cell mobilization in patients following frontline induction therapy in the MASTER and GRIFFIN phase 2 clinical studies by examining stem cell mobilization yields, apheresis attempts, and engraftment outcomes for patients from each study. Adult transplantation-eligible patients with NDMM received induction therapy consisting of daratumumab plus carfilzomib/lenalidomide/dexamethasone (D-KRd) for four 28-day cycles in the single-arm MASTER trial or lenalidomide/bortezomib/dexamethasone (RVd) with or without daratumumab (D) for four 21-day cycles in the randomized GRIFFIN trial, followed by stem cell mobilization and ASCT in both studies. Institutional practice differed regarding plerixafor use for stem cell mobilization; the strategies were upfront (ie, planned plerixafor use) or rescue (ie, plerixafor use only after mobilization parameters indicated failure with granulocyte colony-stimulating factor [G-CSF] alone). Descriptive analyses were used to summarize patient characteristics, stem cell mobilization yields, and engraftment outcomes. In MASTER, 116 D-KRd recipients underwent stem cell mobilization and collection at a median of 24 days after completing induction therapy. In GRIFFIN, 175 patients (D-RVd, n = 95; RVd, n = 80) underwent mobilization at a median of 27 days after completing D-RVd induction therapy and 24 days after completing RVd induction therapy. Among those who underwent mobilization and collection, 7% (8 of 116) of D-KRd recipients, 2% (2 of 95) of D-RVd recipients, and 6% (5 of 80) of RVd recipients did not meet the center-specific minimally required CD34⁺ cell yield in the first mobilization attempt; however, nearly all collected sufficient stem cells for ASCT on remobilization. Among patients who underwent mobilization, plerixafor use, either upfront or as a rescue strategy, was higher in patients receiving D-KRd (97%; 112 of 116) and D-RVd (72%; 68 of 95) compared with those receiving RVd (55%; 44 of 80). The median total CD34⁺ cell collection was 6.0 × 10⁶/kg (range, 2.2 to 13.9 × 10⁶/kg) after D-KRd induction, 8.3 × 10⁶/kg (range, 2.6 to 33.0 × 10⁶/kg) after D-RVd induction, and 9.4 × 10⁶/kg (range, 4.1 to 28.7 × 10⁶/kg) after RVd induction; the median days for collection were 2, 2, and 1, respectively. Among patients who underwent mobilization, 98% (114 of 116) of D-KRd patients, 99% (94 of 95) of D-RVd patients, and 98% (78 of 80) of RVd patients underwent ASCT using median CD34⁺ cell doses of 3.2 × 10⁶/kg, 4.2 × 10⁶/kg, and 4.8 × 10⁶/kg, respectively. The median time to neutrophil recovery was 12 days in all 3 treatment groups across the 2 trials. Because both trials used different criteria to define platelet recovery, data on platelet engraftment using the same criteria are not available. Four cycles of daratumumab- and lenalidomide-based quadruplet induction therapy had a minimal impact on stem cell mobilization and allowed predictable stem cell harvesting and engraftment in all patients who underwent ASCT. Upfront plerixafor strategy may be considered, but many patients were successfully collected with the use of G-CSF alone or rescue plerixafor.

A plain language summary of daratumumab plus lenalidomide/bortezomib/dexamethasone in transplant-eligible Black patients with newly diagnosed multiple myeloma in the GRIFFIN study

WHAT IS THIS SUMMARY ABOUT?

This is a summary of a publication about Black participants of the GRIFFIN clinical study that was published in Blood Cancer Journal in April 2022. The GRIFFIN clinical study looked at the treatment combination of daratumumab plus a standard therapy for multiple myeloma (called RVd therapy, which stands for lenalidomide, bortezomib, and dexamethasone) in adult patients who had not been treated before for multiple myeloma and so were considered to have newly diagnosed multiply myeloma. Multiple myeloma is a blood cancer of plasma cells. Based on the participants' age, medical history, and indicators of good general health, the participants in the GRIFFIN study were also eligible to receive autologous stem cell transplant as part of their therapy. This summary describes results for the Black participants of the GRIFFIN clinical study who received daratumumab plus RVd therapy (called D-RVd) to see if D-RVd therapy is better than RVd therapy at reducing the amount of multiple myeloma cancer cells in a patient's body.

WHY DID THE RESEARCHERS EVALUATE THE RESULTS FOR BLACK PATIENTS IN THE GRIFFIN STUDY?

Due to racial disparities leading to historically low representation of minority groups in clinical studies, optimal treatments are not defined for Black patients with newly diagnosed multiple myeloma. Since previously published results from the overall population in the GRIFFIN study indicated that D-RVd therapy was better than RVd therapy, the researchers wanted to determine if this was also the case among Black participants.

WHAT WERE THE RESULTS?

Out of 207 participants in the GRIFFIN study, 15% (32 participants) were Black and 78% (161 participants) were White. In both Black and White participants, D-RVd therapy reduced the amount of myeloma cancer cells more than RVd therapy. Additionally, D-RVd and RVd therapy had similar safety results for Black and White participants.

WHAT DO THE RESULTS MEAN?

This analysis of GRIFFIN by race shows that Black people benefit from the daratumumab-containing D-RVd therapy as much as White people. Additionally, D-RVd therapy had similar safety results to RVd therapy for both Black and White people. Clinical Trial Registration: NCT02874742 (ClinicalTrials.gov).

Evaluation of geranylgeranyl diphosphate synthase inhibition as a novel strategy for the treatment of osteosarcoma and Ewing sarcoma

Rab GTPases are critical regulators of protein trafficking in the cell. To ensure proper cellular localization and function, Rab proteins must undergo a posttranslational modification, termed geranylgeranylation. In the isoprenoid biosynthesis pathway, the enzyme geranylgeranyl diphosphate synthase (GGDPS) generates the 20-carbon isoprenoid donor (geranylgeranyl pyrophosphate [GGPP]), which is utilized in the prenylation of Rab proteins. We have pursued the development of GGDPS inhibitors (GGSI) as a novel means to target Rab activity in cancer cells. Osteosarcoma (OS) and Ewing sarcoma (ES) are aggressive childhood bone cancers with stagnant survival statistics and limited treatment options. Here we show that GGSI treatment induces markers of the unfolded protein response (UPR) and triggers apoptotic cell death in a variety of OS and ES cell lines. Confirmation that these effects were secondary to cellular depletion of GGPP and disruption of Rab geranylgeranylation was confirmed via experiments using exogenous GGPP or specific geranylgeranyl transferase inhibitors. Furthermore, GGSI treatment disrupts cellular migration and invasion in vitro. Metabolomic profiles of OS and ES cell lines identify distinct changes in purine metabolism in GGSI-treated cells. Lastly, we demonstrate that GGSI treatment slows tumor growth in a mouse model of ES. Collectively, these studies support further development of GGSIs as a novel treatment for OS and ES.

Geranylgeranyl diphosphate synthase: Role in human health, disease and potential therapeutic target

Geranylgeranyl diphosphate synthase (GGDPS), an enzyme in the isoprenoid biosynthesis pathway, is responsible for the production of geranylgeranyl pyrophosphate (GGPP). GGPP serves as a substrate for the post-translational modification (geranylgeranylation) of proteins, including those belonging to the Ras superfamily of small GTPases. These proteins play key roles in signalling pathways, cytoskeletal regulation and intracellular transport, and in the absence of the prenylation modification, cannot properly localise and function. Aberrant expression of GGDPS has been implicated in various human pathologies, including liver disease, type 2 diabetes, pulmonary disease and malignancy. Thus, this enzyme is of particular interest from a therapeutic perspective. Here, we review the physiological function of GGDPS as well as its role in pathophysiological processes. We discuss the current GGDPS inhibitors under development and the therapeutic implications of targeting this enzyme.

Aminopeptidases in Cancer, Biology and Prospects for Pharmacological Intervention

Aminopeptidases, which catalyze the cleavage of amino acids from the amino terminus of proteins, are widely distributed in the natural world and play a crucial role in cellular processes and functions, including metabolism, signaling, angiogenesis, and immunology. They are also involved in the homeostasis of amino acids and proteins that are required for cellular proliferation. Tumor cells are highly dependent on the exogenous supply of amino acids for their survival, and overexpression of aminopeptidase facilitates rapid tumor cell proliferation. In addition, clinical studies have demonstrated that patients with cancers with high aminopeptidase expression often have poorer outcomes. Emerging evidence supports the rationale of inhibiting aminopeptidase activity as a targeted approach for novel treatment options, as limiting the availability of amino acids can be selectively lethal to tumor cells. While there are agents that directly target aminopeptidases that demonstrate potential as cancer therapies, such as bestatin and tosedostat, more selective and more targeted therapeutic approaches are needed. This article specifically looks at the biological role of aminopeptidases in both normal and cancer processes, and their potential as a biological target for future therapeutic strategies. When examining previous publications, most do not cover aminopeptidases and their role in cancer processes. Aminopeptidases play a vital role in cell processes and functions; however, their overexpression may lead to a rapid proliferation of tumor cells. Emerging evidence supports the rationale of leveraging aminopeptidase activity as a targeted approach for new oncological treatments. This article specifically looks at the biological role of aminopeptidases in both normal and cancer processes, and their potential as a biological target for future therapeutic strategies.

Ciltacabtagene autoleucel for the treatment of multiple myeloma

While treatment options for multiple myeloma (MM) are continuing to expand, this disease remains one characterized by requiring multiple lines of therapy, with generally decreasing effectiveness of each subsequent line. The development of B-cell maturation antigen (BCMA)-directed chimeric antigen receptor (CAR) T-cell therapy has proven an exception to this rule. In the trial that led to approval of the BCMA CAR T-cell therapy ciltacabtagene autoleucel (cilta-cel) by the U.S. Food and Drug Administration (FDA), deep and durable response rates were observed in heavily pretreated patients. In this review we summarize the available clinical trial data for cilta-cel, including discussion on notable adverse events, as well as discuss ongoing studies that are likely to lead to paradigm changes in the management of MM. In addition, we discuss the issues that currently surround the real-world utilization of cilta-cel.

Targeting the Isoprenoid Biosynthetic Pathway in Multiple Myeloma

Multiple myeloma (MM) is a plasma cell malignancy for which there is currently no cure. While treatment options for MM have expanded over the last two decades, all patients will eventually become resistant to current therapies. Thus, there is an urgent need for novel therapeutic strategies to treat MM. The isoprenoid biosynthetic pathway (IBP) is responsible for the post-translational modification of proteins belonging to the Ras small GTPase superfamily, such as Ras, Rho and Rab family members. Given the important roles these GTPase proteins play in various cellular processes, there is significant interest in the development of inhibitors that disturb their prenylation and consequently their activity in MM cells. Numerous preclinical studies have demonstrated that IBP inhibitors have anti-MM effects, including the induction of apoptosis in MM cells and inhibition of osteoclast activity. Some IBP inhibitors have made their way into the clinic. For instance, nitrogenous bisphosphonates are routinely prescribed for the management MM bone disease. Other IBP inhibitors, including statins and farnesyltransferase inhibitors, have been evaluated in clinical trials for MM, while there is substantial preclinical investigation into geranylgeranyl diphosphate synthase inhibitors. Here we discuss recent advances in the development of IBP inhibitors, assess their mechanism of action and evaluate their potential as anti-MM agents.

Daratumumab plus lenalidomide, bortezomib and dexamethasone in newly diagnosed multiple myeloma: Analysis of vascular thrombotic events in the GRIFFIN study

Patients with multiple myeloma are at increased risk of vascular thromboembolic events (VTEs). This post hoc analysis evaluated VTEs in the randomised phase 2 GRIFFIN study (ClinicalTrials.gov Identifier: NCT02874742) that investigated lenalidomide/bortezomib/dexamethasone (RVd) ± daratumumab (D). Patients with newly diagnosed multiple myeloma who were eligible for autologous stem cell transplantation (ASCT) received D-RVd/RVd induction, high-dose therapy and ASCT, D-RVd/RVd consolidation and up to 2 years of lenalidomide maintenance therapy ± D. VTE prophylaxis was recommended (at least aspirin, ≥162 mg daily) in accordance with International Myeloma Working Group guidelines. In the safety population (D-RVd, n = 99; RVd, n = 102), VTEs occurred in 10.1% of D-RVd patients and 15.7% of RVd patients; grade 2-4 VTEs occurred in 9.1% and 14.7%, respectively. Median time to the first onset of VTE was longer for D-RVd versus RVd patients (305 days vs 119 days). Anti-thrombosis prophylaxis use was similar between arms (D-RVd, 84.8% vs RVd, 83.3%); among patients with VTEs, prophylaxis use at time of first VTE onset was 60.0% for D-RVd and 68.8% for RVd. In summary, the addition of daratumumab to RVd did not increase the incidence of VTEs, but the cumulative VTE incidence was relatively high in this cohort and anti-thrombotic prophylaxis use was suboptimal.

Proceedings from the Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Immune and Cellular Therapy in Multiple Myeloma

The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup conducted a workshop on Immune and Cellular Therapy in Multiple Myeloma on January 7, 2022. This workshop included presentations by basic, translational, and clinical researchers with expertise in plasma cell dyscrasias. Four main topics were discussed: platforms for myeloma disease evaluation, insights into pathophysiology, therapeutic target and resistance mechanisms, and cellular therapy for multiple myeloma. Here we provide a comprehensive summary of these workshop presentations.

Ethical challenges with CAR T slot allocation with idecabtagene vicleucel manufacturing access

e20021

Background: CAR T cell therapies are FDA approved for patients with triple refractory multiple myeloma (MM) and >4 lines of therapy. The median survival of this is group is less than 12 months so salvage therapies need to be implemented quickly. Real-world access to CAR T remains challenging due to supply chain limitations impacting manufacturing. The goal of this study was to evaluate how centers are handling the challenges of CAR T slot allocation. Methods: MM CAR T physician leaders at each CAR T treatment center certified for idecabtagene vicleucel across the US were surveyed. Results: We received responses from 15/20 centers. Summary of CAR T volumes and outcomes of patient on waitlists are shown in the table. The median time on the waiting list was 6 months with only 25% of patients receiving CAR T eventually. For patient selection, all centers reported using a committee of experienced CART physicians to ensure consistency. Selection committee included: primary MD (n=9), CAR T MD (n=12), social workers (n=3), CAR T RN (n=10), APP (n=2), pharmacists (n=2) and ethicists (n=1). To ensure transparency, centers have clear selection criteria (n=10), priority score (n=8) and selection timeline (n=11) . To ensure accountability, centers document priority scores (n=5) and have pre-specified criteria (n=9) for selection. Centers also reported using ethical principles for selection: a) equal treatment: time spent on waiting list (n=8); b) priority to the worst-off: limited therapeutic options (n=10), MM burden (n=7), ineligible for trials (n=2); c) maximize benefit: most likely to complete apheresis (n=8) or infusion (n=8) or achieve response (n=6) and d) social value: younger pts (n=2). Maximizing benefit was considered the most important criterion by 7 centers. Conclusions: More stringent GMP manufacturing requirements with FDA approved CAR T and real-world practice with broader patient demographics can present challenges to implementation of CAR T in standard of practice. Our study is the first attempt to evaluate and highlight existing issues with MM CAR T access and the variability and challenges in patient selection. Learning from other models of resource allocation (ex: UNOS) and sharing experience across centers can help providers optimize slot allocation to improve accrual. Increasing supplies of key reagents and novel manufacturing methods(eg: non-viral vectors and allogeneic CAR) could help overcome these limitations. [Table: see text]

A review of the current status of lenalidomide maintenance therapy in multiple myeloma in 2022

INTRODUCTION

Recent advances in the diagnosis and management of multiple myeloma (MM) have improved patient outcomes. This progress in our understanding of MM has resulted in continuous suppressive therapy concepts, including induction, high dose chemotherapy with autologous stem cell transplantation (ASCT), consolidation, and maintenance therapy. The foundation of maintenance therapy has been with lenalidomide. Other novel immunomodulatory drugs (IMiDs), proteasome inhibitors (PIs), and targeted monoclonal antibodies have also contributed to this evolution.

AREAS COVERED

This review summarizes the outcomes from phase II/III trials with long-term lenalidomide maintenance therapy alone or in combination with other agents in post-ASCT and non-transplant settings for newly diagnosed patients with MM. We review recent data considering a combination with newer medications and ongoing trials. We also review the optimal duration, MRD negativity rate, and safety and tolerability aspects of lenalidomide maintenance therapy. This review aims to present the current and emerging clinical evidence that supports using lenalidomide as a backbone for maintenance therapy in patients with MM.

EXPERT OPINION

There is increasing evidence to support lenalidomide as the backbone of combination therapy in the maintenance setting.

Geranylgeranyl diphosphate synthase inhibitor and proteasome inhibitor combination therapy in multiple myeloma

Background

Multiple myeloma (MM) remains an incurable malignancy, despite the advent of therapies such as proteosome inhibitors (PIs) that disrupt protein homeostasis and induce ER stress. We have pursued inhibition of geranylgeranyl diphosphate synthase (GGDPS) as a novel mechanism by which to target protein homeostasis in MM cells. GGDPS inhibitors (GGSI) disrupt Rab geranylgeranylation, which in turn results in perturbation of Rab-mediated protein trafficking, leading to accumulation of intracellular monoclonal protein, induction of ER stress and apoptosis. Our lead GGSI, RAM2061, has demonstrated favorable pharmacokinetic properties and in vivo efficacy. Here we sought to evaluate if combination therapy with GGSI and PI would result in enhanced disruption of the unfolded protein response (UPR) and increase anti-MM efficacy.

Methods

MTT assays were conducted to evaluate the cytotoxic effects of combining RAM2061 with bortezomib in human MM cells. The effects of RAM2061 and/or PI (bortezomib or carfilzomib) on markers of UPR and apoptosis were evaluated by a combination of immunoblot (ATF4, IRE1, p-eIF2a, cleaved caspases and PARP), RT-PCR (ATF4, ATF6, CHOP, PERK, IRE1) and flow cytometry (Annexin-V). Induction of immunogenic cell death (ICD) was assessed by immunoblot (HMGB1 release) and flow cytometry (calreticulin translocation). Cell assays were performed using both concurrent and sequential incubation with PIs. To evaluate the in vivo activity of GGSI/PI, a flank xenograft using MM.1S cells was performed.

Results

Isobologram analysis of cytotoxicity data revealed that sequential treatment of bortezomib with RAM2061 has a synergistic effect in MM cells, while concurrent treatment was primarily additive or mildly antagonistic. The effect of PIs on augmenting RAM2061-induced upregulation of UPR and apoptotic markers was dependent on timing of the PI exposure. Combination treatment with RAM2061 and bortezomib enhanced activation of ICD pathway markers. Lastly, combination treatment slowed MM tumor growth and lengthened survival in a MM xenograft model without evidence of off-target toxicity.

Conclusion

We demonstrate that GGSI/PI treatment can potentiate activation of the UPR and apoptotic pathway, as well as induce upregulation of markers associated with the ICD pathway. Collectively, these findings lay the groundwork for future clinical studies evaluating combination GGSI and PI therapy in patients with MM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40164-022-00261-6.

The 2020 BMT CTN Myeloma Intergroup Workshop on Immune Profiling and Minimal Residual Disease Testing in Multiple Myeloma

The fifth annual Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Immune Profiling and Minimal Residual Disease Testing in Multiple Myeloma was conducted as one of the American Society of Hematology Annual Meeting Scientific Workshops on Thursday December 3, 2020. This workshop focused on four main topics: (1) integrating minimal residual disease into clinical trial design and practice; (2) the molecular and immunobiology of disease evolution and progression in myeloma; (3) adaptation of next-generation sequencing, next-generation flow cytometry, and cytometry by time of flight techniques; and (4) chimeric antigen receptor T-cell and other cellular therapies for myeloma. In this report, we provide a summary of the workshop presentations and discuss future directions in the field.

Impact of α-modifications on the activity of triazole bisphosphonates as geranylgeranyl diphosphate synthase inhibitors

Agents that inhibit the enzyme geranylgeranyl diphosphate synthase (GGDPS) have anti-cancer activity and our prior studies have investigated the structure-function relationship for a family of isoprenoid triazole bisphosphonates as GGDPS inhibitors. To further explore this structure-function relationship, a series of novel α-modified triazole phosphonates was prepared and evaluated for activity as GGDPS inhibitors in enzyme and cell-based assays. These studies revealed flexibility at the α position of the bisphosphonate derivatives with respect to being able to accommodate a variety of substituents without significantly affecting potency compared to the parent unsubstituted inhibitor. However, the monophosphonate derivatives lacked activity. These studies further our understanding of the structure-function relationship of the triazole-based GGDPS inhibitors and lay the foundation for future studies evaluating the impact of α-modifications on in vivo activity.

Effect of geriatric assessment (GA) and genetic profiling on overall survival (OS) of older adults with acute myeloid leukemia (AML)

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Background: GA can predict the risk of toxicities of chemotherapy in older adults. Genetic risk categories correlate with OS in AML. We previously reported a reduction in early mortality in a pre-planned interim analysis of a phase II trial with the use of GA and genetic profiling to personalize therapy selection (NCT03226418) (Blood 2019; 134(s1):120). Here, we present the results of a propensity score matched analysis demonstrating an improvement in OS over a historical control. Methods: Patients ≥60 years with a new diagnosis of AML underwent GA. Patients were considered fit for intensive chemotherapy if they had robust physical function [normal activities of daily living (ADL) and instrumental ADL, and short physical performance battery score of ≥10 out of 12], normal cognitive function (Montreal Cognitive Assessment score of ≥26 out of 30), and hematopoietic cell transplantation comorbidity index (HCT CI) of 0-2 (except for treatment related AML, where a score of 0-2 in addition to the prior history of malignancy was acceptable). Genetic profiling for therapy selection relied on karyotyping and followed the 2017 ELN criteria. Fit patients with good or intermediate-risk AML received intensive chemotherapy. Patients with high-risk AML received low-intensity chemotherapy, or CPX 351 if they were fit and met the FDA-approved indications. Pragmatic aspects of the trial included broad eligibility criteria (e.g. patients on treatment for other malignancy were enrolled) and co-management of patients with community oncologists. Mortality was compared with a historical control treated during the years 2004-2016 (after approval of HMA) and matched on gender, age, Karnofsky Performance Status (KPS), HCT CI and ELN risk category. Results: Treatment group (n = 27) vs. historical controls (n = 32) were matched in terms of age (median age, 70 vs. 68.5 years), ELN risk category (adverse risk 59% vs. 53%), HCT CI (median score of 2), KPS (median 80 vs. 85), and gender (male 44% vs. 50%). In the treatment group, 3 patients received intensive chemotherapy: CPX 351 (n = 2) or 7+3+ gemtuzumab (n = 1). Other patients received HMA alone (n = 16), decitabine and midostaurin (n = 3), or azacitidine and venetoclax after the approval of venetoclax (n = 5). Treatment in the historical control included intensive chemotherapy (n = 20) such as 7+3, or mostly HMA based low intensity chemotherapy (n = 12). OS was significantly higher in the treatment group over historical control with 1-year OS of 66% (95% CI 60-87%) vs. 16% (95% CI 7-35%). Conclusions: Our model to personalize AML therapy selection represents an innovative approach to precision medicine that incorporates both GA for patient profiling and genetic profiling of leukemia cells. Our results appear promising with superior OS (an absolute difference of 50% in 1-year OS) compared to a matched historical control. Clinical trial information: NCT03226418.

Visual dysfunction in a mouse model of chemotherapy-related neurotoxicity

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Background: Chemotherapy-related neurotoxicity (CRNT) poses challenges to long-term outcomes of cancer survivors. Visual function remains relatively unexplored in CRNT. Preliminary clinical work from our group suggests contrast sensitivity may be impaired in patients receiving chemotherapy. Here, we sought to isolate effects of chemotherapy on visual dysfunction in a mouse model. Methods: 10-week old C57BL/6J mice received either 4, 7, or 10 weekly intraperitoneal injections of chemotherapy (CTX group; n=15) or physiologic saline (SAL group; n=12). CTX mice received cyclophosphamide (50 mg/kg) and doxorubicin (2 mg/kg). Contrast sensitivity was assessed using an optomotor response (OMR) chamber. Psychometric functions were fitted to OMR contrast response functions to derive measures of contrast sensitivity (K), stimulus responsivity (Rmax), and stimulus selectivity (n). Electroretinography (ERG) waveforms, which measure light-evoked retinal neural activity, were recorded under scotopic (rod-driven) conditions and decomposed to isolate photoreceptor (a-wave), bipolar cell (b-wave), and interneuron amacrine cell (oscillatory potentials [OP]) activity. OMR and ERG were measured prior to and following treatment. Dependent- and independent-sample t-tests assessed within- and between-group changes, respectively, in outcome measures. Results: Outcome measures are reported in Table 1. SAL relative to CTX mice showed greater weight gain (p=0.004). OMR revealed increases in Rmax (pCTX=0.002; pSAL=0.11) and K (pCTX=0.80; pSAL=0.06) parameters in SAL but not CTX mice. ERG results revealed significant declines in OP peak frequency in CTX relative to SAL mice (p=0.006). Other OMR and ERG measures showed no within- or between-group differences (p>0.10). Decreases in weight were associated with decreases in Rmax (R2=0.25, p=.008) and OP peak frequency (R2=0.20, p=.02). Conclusions: Our animal model showed chemotherapy-related visual dysfunction. Mice receiving chemotherapy showed relative declines in contrast sensitivity, stimulus responsivity, and oscillatory neural activity, suggestive of disrupted neuronal circuits within the visual pathway. Future studies will focus on understanding neuronal mechanisms of visual pathway dysfunction and translating findings to clinical studies. [Table: see text]

Evolution of Treatment Paradigms in Newly Diagnosed Multiple Myeloma

The plasma cell neoplasm multiple myeloma (MM) is currently considered incurable. However, significant advances in treatment options over the past 20 years have led to unprecedented response rates to initial therapy as well as prolonged survival rates. Induction regimens have evolved from alkylator-based therapies to those consisting of immunomodulatory drugs and proteasome inhibitors. The combination of bortezomib/lenalidomide/dexamethasone (VRd) has emerged as a standard regimen for both transplant-eligible (TE) and transplant-ineligible (TI) patient populations. More recent efforts have focused on the incorporation of monoclonal antibody therapy into the newly diagnosed setting, particularly anti-CD38 monoclonal antibodies. In the TI patient population, the combination of daratumumab/lenalidomide/dexamethasone is now considered another standard therapy. In the TE setting, it remains to be determined whether the addition of daratumumab to the VRd backbone results in improved long-term outcomes. Recent studies have confirmed the progression-free survival benefit of upfront autologous stem cell transplant and have established lenalidomide maintenance as a standard of care. Multiple studies are evaluating whether inclusion of monoclonal antibody therapy in the maintenance setting will improve outcomes. The optimal management of newly diagnosed patients with high-risk cytogenetics remains to be determined. We discuss the emerging therapies that will likely shape management of newly diagnosed MM in the future.

In vivo evaluation of combination therapy targeting the isoprenoid biosynthetic pathway

Geranylgeranyl diphosphate synthase (GGDPS), an enzyme in the isoprenoid biosynthetic pathway (IBP), produces the isoprenoid (geranylgeranyl pyrophosphate, GGPP) used in protein geranylgeranylation reactions. Our prior studies utilizing triazole bisphosphonate-based GGDPS inhibitors (GGSIs) have revealed that these agents represent a novel strategy by which to induce cancer cell death, including multiple myeloma and pancreatic cancer. Statins inhibit the rate-limiting enzyme in the IBP and potentiate the effects of GGSIs in vitro. The in vivo effects of combination therapy with statins and GGSIs have not been determined. Here we evaluated the effects of combining VSW1198, a novel GGSI, with a statin (lovastatin or pravastatin) in CD-1 mice. Twice-weekly dosing with VSW1198 at the previously established maximally tolerated dose in combination with a statin led to hepatotoxicity, while once-weekly VSW1198-based combinations were feasible. No abnormalities in kidney, spleen, brain or skeletal muscle were observed with combination therapy. Combination therapy disrupted protein geranylgeranylation in vivo. Evaluation of hepatic isoprenoid levels revealed decreased GGPP levels in the single drug groups and undetectable GGPP levels in the combination groups. Additional studies with combinations using 50% dose-reductions of either VSW1198 or lovastatin revealed minimal hepatotoxicity with expected on-target effects of diminished GGPP levels and disruption of protein geranylgeranylation. Combination statin/GGSI therapy significantly slowed tumor growth in a myeloma xenograft model. Collectively, these studies are the first to demonstrate that combination IBP inhibitor therapy alters isoprenoid levels and disrupts protein geranylgeranylation in vivo as well as slows tumor growth in a myeloma xenograft model, thus providing the framework for future clinical exploration.

Summary of the 2019 Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Minimal Residual Disease and Immune Profiling

The Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup has organized an annual workshop focused on minimal residual disease (MRD) testing and immune profiling (IP) in multiple myeloma since 2016. In 2019, the workshop took place as an American Society of Hematology (ASH) Friday Scientific Workshop titled "Immune Profiling and Minimal Residual Disease Testing in Multiple Myeloma." This workshop focused on 4 main topics: the molecular and immunologic evolution of plasma cell disorders, development of new laboratory- and imaging-based MRD assessment approaches, chimeric antigen receptor T cell therapy research, and statistical and regulatory issues associated with novel clinical endpoints. In this report, we provide a summary of the workshop and discuss future directions.

Amides as bioisosteres of triazole-based geranylgeranyl diphosphate synthase inhibitors

Geranylgeranyl diphosphate synthase (GGDPS) inhibitors are of potential therapeutic interest as a consequence of their activity against the bone marrow cancer multiple myeloma. A series of bisphosphonates linked to an isoprenoid tail through an amide linkage has been prepared and tested for the ability to inhibit GGDPS in enzyme and cell-based assays. The amides were designed as analogues to triazole-based GGDPS inhibitors. Several of the new compounds show GGDPS inhibitory activity in both enzyme and cell assays, with potency dependent on chain length and olefin stereochemistry.

Visual Pathway Degeneration in Chemotherapy-Related Neurotoxicity: A Review and Directions for Future Research

Chemotherapy-related neurotoxicity (CRNT) is an emerging public health concern. Visual pathway degeneration may be a symptom of CRNT. We surveyed the current literature for evidence of visual pathway degeneration in cancer patients receiving chemotherapy. A systematic review was conducted in PubMed. Six published articles met our inclusion criteria. The studies showed reduced retinal thickness, primarily in the retinal nerve fibre layer, and impaired inner retinal function in patients receiving chemotherapy. In summary, the current literature suggests chemotherapy may induce visual pathway degeneration. Future research may benefit from improving study design, exploring mechanisms of chemotherapy-related visual pathway degeneration, and incorporating these findings into biomarker development.

Survival of Older Adults With Newly Diagnosed Acute Myeloid Leukemia: Effect of Using Multiagent Versus Single-agent Chemotherapy

BACKGROUND

Controversy exists regarding the optimal chemotherapy regimen for older adults with acute myeloid leukemia (AML).

PATIENTS AND METHODS

We analyzed data from the US National Cancer Data Base of 25,621 patients aged 60 to 79 years, with a diagnosis of AML from 2004 to 2014, who had received single-agent versus multiagent chemotherapy. A Cox proportional hazard model was used for overall survival (OS) analysis for the entire study cohort and separately for patients who had received single-agent (n = 6743) versus multiagent (n = 6743) chemotherapy, matched for age, Charlson comorbidity index, and AML subtype.

RESULTS

The use of multiagent chemotherapy was high overall (70%) but declined with factors, such as increasing age, Charlson comorbidity index, AML subtype other than good risk, academic center, lower rate of high school graduation, and more recent year of diagnosis. Patients treated with multiagent chemotherapy had greater 1-year OS (43% vs. 28%), especially for patients aged 60 to 69 years and those with good-risk AML or Charlson comorbidity index of 0 to 1. OS (hazard ratio, 1.32; 95% confidence interval, 1.28-1.36) remained more favorable for the multiagent chemotherapy group on multivariable analysis. This was confirmed in a matched cohort analysis.

CONCLUSIONS

To the best of our knowledge, this is the largest real-world study that has demonstrated an association between factors such as age, comorbidity, and AML subtype and the use of multiagent chemotherapy. The use of multiagent chemotherapy was associated with improved OS, especially for patients aged <70 years, those with good-risk AML, and those with a low Charlson comorbidity index.

Long-Term Follow-up of CALGB (Alliance) 100001: Autologous Followed by Nonmyeloablative Allogeneic Transplant for Multiple Myeloma

CALGB (Alliance) 100001 was a phase II study evaluating autologous stem cell transplant (ASCT) followed by nonmyeloablative allogeneic stem cell transplant (alloSCT) in patients with multiple myeloma who had received no more than 18 months of prior therapy and had experienced no more than 1 prior progression event. Conditioning for ASCT was with high-dose melphalan (200 mg/m²). The alloSCT reduced-intensity conditioning (RIC) regimen consisted of fludarabine (30 mg/m²/d i.v. on days -7 through -3) and cyclophosphamide (1 g/m²/d i.v. on days -4 through -3). The primary objective was to determine the 6-month post-alloSCT treatment-related mortality (TRM) rate. Additional objectives included determining the proportion of patients who could complete this tandem ASCT-alloSCT approach in a cooperative group setting, overall response rates, rates of donor chimerism, rates of graft-versus-host disease (GVHD), disease-free survival, and overall survival (OS). Sixty patients were enrolled, of whom 57 (95%) completed ASCT and 49 (82%) completed tandem ASCT-alloSCT. The TRM rate was 2% (1/49; 90% confidence interval, 0.10% to 9.3%). Moderate to severe (grades 2 to 3) acute GVHD was observed in 13 of 49 alloSCT patients (27%). One patient died due to GVHD within 9 months of alloSCT. Twenty-seven of the 49 patients (55%) who underwent alloSCT reported chronic GVHD as either limited (15/49; 31%) or extensive (12/49; 24%) in the first year post-alloSCT and prior to the start of nonprotocol therapy for progressive disease. With a median follow-up for survival of 11 years, the median OS time is 6.6 years and the median time to disease progression is 3.6 years. Similar to other studies, this study confirmed that tandem ASCT/alloSCT is associated with durable disease control in a subset of patients. This study demonstrated the feasibility of performing tandem ASCT/alloSCT in a cooperative group setting and determined that a fludarabine/cyclophosphamide RIC regimen is associated with a very low TRM rate.

Neurophysiologic and ophthalmic markers of chemotherapy-related cognitive impairment in patients diagnosed with hematologic cancer: A feasibility study

BACKGROUND

Biomarkers of chemotherapy-related cognitive impairment (CRCI) in hematologic cancer are understudied and underdeveloped. We evaluated the feasibility of using ophthalmic and neurophysiologic markers to assess CRCI in hematologic cancer.

METHODS

Hematologic cancer patients either receiving (Ctx+) or not receiving (Ctx-) chemotherapy were recruited from a tertiary medical center. Demographically-matched healthy controls (HC) were also recruited. Ctx+ participants completed the following study visits: (1) after diagnosis but prior to chemotherapy (baseline); (2) after one treatment cycle (one-month post-baseline); and (3) after three treatment cycles (three-months post-baseline). Comparison subjects completed assessments at similar intervals. Participants completed: (1) neuropsychological assessments of attention and executive function; (2) neurophysiologic assessments of control over spatial attention and working memory; and (3) ophthalmic assessments of contrast sensitivity and optical coherence tomography (OCT).

RESULTS

We enrolled 45 participants (15 per group), and 30 participants (Ctx+ = 8; Ctx- = 10; HC = 12) completed all study visits. Ctx+ participants performed worse than HC participants on neuropsychological measures of attention and executive function. Both Ctx+ and Ctx- participants showed changes in neurophysiologic measures of control over spatial attention that differed from HC participants. Ctx+ participants showed chemotherapy-related declines in contrast sensitivity that were predicted by OCT retinal nerve fiber layer thickness (RNFL) changes. Changes in neurophysiologic measures of control over spatial attention were also predicted by OCT RNFL changes.

CONCLUSION

We demonstrated the feasibility of using ophthalmic and neurophysiologic markers as rapid and non-invasive measures that may be useful for tracking CRCI in hematologic cancer.

Determination of Minimal Residual Disease in Multiple Myeloma: Does It Matter?

PURPOSE OF REVIEW

The ability to detect minimal residual disease (MRD) in myeloma has improved due to advances in flow cytometry and sequencing methodologies. Here, we evaluate recent clinical trial data and explore the current and future roles of MRD assessment in the context of clinical trial design and clinical practice.

RECENT FINDINGS

A review of recent phase III studies reveals that achievement of MRD negativity is associated with improved progression-free survival (PFS) and/or overall survival (OS). Treatment arms that are more effective from a PFS or overall response rate perspective are also associated with superior MRD negativity rates. The current standard MRD methodologies are limited by requiring bone marrow samples and refinement of methodologies that can detect disease outside of the bone marrow is needed. Currently, MRD is a prognostic biomarker and further efforts are required to determine whether it can serve as a surrogate endpoint. The use of MRD status to guide treatment decisions is currently not recommended outside the confines of a clinical trial.

Developments in continuous therapy and maintenance treatment approaches for patients with newly diagnosed multiple myeloma

The evolving paradigm of continuous therapy and maintenance treatment approaches in multiple myeloma (MM) offers prolonged disease control and improved outcomes compared to traditional fixed-duration approaches. Potential benefits of long-term strategies include sustained control of disease symptoms, as well as continued cytoreduction and clonal control, leading to unmeasurable residual disease and the possibility of transforming MM into a chronic or functionally curable condition. "Continuous therapy" commonly refers to administering a doublet or triplet regimen until disease progression, whereas maintenance approaches typically involve single-agent or doublet treatment following more intensive prior therapy with autologous stem cell transplant (ASCT) or doublet, triplet, or even quadruplet induction therapy. However, the requirements for agents and regimens within these contexts are similar: treatments must be tolerable for a prolonged period of time, should not be associated with cumulative or chronic toxicity, should not adversely affect patients' quality of life, should ideally be convenient with a minimal treatment burden for patients, and should not impact the feasibility or efficacy of subsequent treatment at relapse. Multiple agents have been and are being investigated as long-term options in the treatment of newly diagnosed MM (NDMM), including the immunomodulatory drugs lenalidomide and thalidomide, the proteasome inhibitors bortezomib, carfilzomib, and ixazomib, and the monoclonal antibodies daratumumab, elotuzumab, and isatuximab. Here we review the latest results with long-term therapy approaches in three different settings in NDMM: (1) maintenance treatment post ASCT; (2) continuous frontline therapy in nontransplant patients; (3) maintenance treatment post-frontline therapy in the nontransplant setting. We also discuss evidence from key phase 3 trials. Our review demonstrates how the paradigm of long-term treatment is increasingly well-established across NDMM treatment settings, potentially resulting in further improvements in patient outcomes, and highlights key clinical issues that will need to be addressed in order to provide optimal benefit.

Summary of the Third Annual Blood and Marrow Transplant Clinical Trials Network Myeloma Intergroup Workshop on Minimal Residual Disease and Immune Profiling

The third annual Blood and Marrow Transplant Clinical Trials Network (BMT CTN) Myeloma Intergroup Workshop on Minimal Residual Disease and Immune Profiling was held on November 29, 2018, at the American Society of Hematology (ASH) annual meeting. This workshop featured the latest research focused on minimal residual disease (MRD) assessment and immune profiling (IP) in myeloma as well as discussion of the statistical and regulatory issues intrinsic to the development of MRD as a surrogate endpoint. In this report, we provide a summary of the workshop and focus on the integration of MRD and IP assessment into trial design and clinical practice.

Novel benzimidazole phosphonates as potential inhibitors of protein prenylation

Benzimidazole carboxyphosphonates and bisphosphonates have been prepared and evaluated for their activity as inhibitors of protein prenylation or isoprenoid biosynthesis. The nature of the phosphonate head group was found to dictate enzyme specificity. The lead carboxyphosphonate inhibits geranylgeranyl transferase II while its corresponding bisphosphonate analogue potently inhibits farnesyl diphosphate synthase. The most active inhibitors effectively disrupted protein prenylation in human multiple myeloma cells.

Maintenance Treatment and Survival in Patients With Myeloma: A Systematic Review and Network Meta-analysis

Importance

Several trials demonstrated the impact of novel agent-based maintenance in newly diagnosed multiple myeloma (NDMM), but there is no current evidence demonstrating the superiority of one regimen over the other, owing to the lack of direct/indirect comparisons.

Objective

To analyze and compare the effectiveness of different maintenance regimens in NDMM via a network meta-analysis.

Data Sources

We performed 2 independent searches in PubMed and Cochrane databases, and then we identified all the records registered after 1999 and on or before November 20, 2017.

Study Selection

By blinded review, we identified prospective phase 3 randomized trials evaluating novel agent-based maintenance in patients with NDMM; the included studies compared at least 2 maintenance approaches; comparators included placebo and no maintenance. From 364 screened records, 11 studies were included.

Data Extraction and Synthesis

We followed (independent extraction) the guidelines provided by the PRISMA Report and the EQUATOR Network. The evidence was synthesized using a network meta-analysis (NMA). To allow comparison of all treatments, no maintenance was selected as common comparator and the effect of placebo was assumed to be the same as no treatment. The best option was identified by a Bayesian consistency model based on hazard ratio (HR), 95% credible interval (CrI), probability of being the best treatment (PbBT), and median ranking distribution (MedR).

Main Outcomes and Measures

Outcomes of interest were progression-free survival (PFS) and overall survival (OS).

Results

Eleven trials and 8 treatments including a total of 5073 participants were included. By PFS analysis, lenalidomide-based regimens (lenalidomide-prednisone, lenalidomide alone) were identified as the most effective options (HR, 0.39 [95% CrI, 0.28-0.53] and 0.47 [95% CrI, 0.39-0.55], respectively; MedR, 1 and 2; overall PbBT, 74%). Four treatments (thalidomide-interferon, thalidomide-bortezomib, bortezomib-prednisone, thalidomide alone) showed an HR in favor of maintenance. By OS analysis, lenalidomide alone was identified as the best option (HR, 0.76; 95% CrI, 0.51-1.16; MedR, 2; PbBT, 38%), followed by bortezomib-thalidomide and bortezomib-prednisone. Similar features were noticed in the restricted network including transplant trials, in the sensitivity analysis, and in most of the prognostic subgroups.

Conclusions and Relevance

Based on PFS and OS results of this NMA, lenalidomide maintenance appears to be the best treatment option, by synthesizing the available evidence of novel agent-based maintenance in the past 20 years.