The addition of daratumumab to lenalinomide and dexamethasone in patients with previously untreated myeloma who were not eligible for high-dose chemotherapy and hematopoietic stem-cell ...transplantation resulted in a higher response rate, an increased depth of response, and longer progression-free survival than lenalidomide and dexamethasone alone.
Targeting intracellular protein turnover by inhibiting the ubiquitin-proteasome pathway as a strategy for cancer therapy is a new addition to our chemotherapeutic armamentarium, and has seen its ...greatest successes against multiple myeloma. The first-in-class proteasome inhibitor, bortezomib, was initially approved for treatment of patients in the relapsed/refractory setting as a single agent, and was recently shown to induce even greater benefits as part of rationally designed combinations that overcome chemoresistance. Modulation of proteasome function is also a rational approach to achieve chemosensitization to other antimyeloma agents, and bortezomib has now been incorporated into the front-line setting. Bortezomib-based induction regimens are able to achieve higher overall response rates and response qualities than was the case with prior standards of care, and unlike these older approaches, maintain efficacy in patients with clinically and molecularly defined high-risk disease. Second-generation proteasome inhibitors with novel properties, such as NPI-0052 and carfilzomib, are entering the clinical arena, and showing evidence of antimyeloma activity. In this spotlight review, we provide an overview of the current state of the art use of bortezomib and other proteasome inhibitors against multiple myeloma, and highlight areas for future study that will further optimize our ability to benefit patients with this disease.
Despite enormous advances, management of multiple myeloma (MM) remains challenging. Multiple factors impact the decision to treat or which regimen to use at MM relapse/progression. Recent major ...randomized controlled trials (RCTs) showed widely varying progression-free survivals (PFS), ranging from a median of 4 months (MM-003) to 23.6 months (ASPIRE). Based on these RCTs, next-generation proteasome inhibitors (carfilzomib and ixazomib), next-generation immunomodulatory agent (pomalidomide), and monoclonal antibodies (elotuzumab and daratumumab) were approved for relapsed and refractory MM. Daratumumab, targeting CD38, has multiple mechanisms of action including modulation of the immunosuppressive bone marrow micro-environment. In addition to the remarkable single agent activity in refractory MM, daratumumab produced deep responses and superior PFS in MM when combined with lenalidomide/dexamethasone, or bortezomib/dexamethasone. Other anti-CD38 antibodies, such as isatuximab and MOR202, are undergoing assessment. Elotuzumab, targeting SLAMF7, yielded superior response rates and PFS when combined with lenalidomide/dexamethasone. New combinations of these next generation novel agents and/or antibodies are undergoing clinical trials. Venetoclax, an oral BH3 mimetic inhibiting BCL2, showed single agent activity in MM with t(11;14), and is being studied in combination with bortezomib/dexamethasone. Selinexor, an Exportin-1 inhibitor, yielded promising results in quad- or penta-refractory MM including patients resistant to daratumumab. Pembrolizumab, an anti-PD1 check-point inhibitor, is being tested in combination with lenalidomide/dexamethasone or pomalidomide/dexamethasone. Chimeric antigen receptor-T cells targeting B-cell maturation antigen have yielded deep responses in RRMM. Finally, salvage autologous stem cell transplantation (ASCT) remains an important treatment in MM relapsing/progressing after a first ASCT. Herein, the clinical trial data of these agents are summarized, cautious interpretation of RCTs highlighted, and algorithm for salvage treatment of relapse/refractory MM proposed.
In 2005, the first guidelines were published on the management of patients with multiple myeloma (MM). An expert panel reviewed the currently available literature as the basis for a set of revised ...and updated consensus guidelines for the diagnosis and management of patients with MM who are not eligible for autologous stem cell transplantation. Here we present recommendations on the diagnosis, treatment of newly diagnosed non-transplant-eligible patients and the management of complications occurring during induction therapy among these patients. These guidelines will aid the physician in daily clinical practice and will ensure optimal care for patients with MM.
The ubiquitin-proteasome pathway (UPP) is an attractive chemotherapeutic target due to its intrinsically stringent regulation of cell cycle, pro-survival, and anti-apoptotic regulators that ...disproportionately favor survival and proliferation in malignant cells. A reversible first-in-class proteasome inhibitor, bortezomib, is Food and Drug Administration approved for multiple myeloma and relapsed/refractory mantle cell lymphoma and has proven to be extremely effective, both as a single agent and in combination. An irreversible second generation proteasome inhibitor, carfilzomib, has shown preclinical effectiveness against hematological and solid malignancies both in vitro and in vivo. Carfilzomib, a peptidyl-epoxyketone functions similarly to bortezomib through primary inhibition of chymotrypsin-like (ChT-L) activity at the b5 subunits of the core 20S proteasome. Carfilzomib is also currently achieving successful response rates within the clinical setting. In addition to conventional proteasome inhibitors, a novel approach may be to specifically target the hematological-specific immunoproteasome, thereby increasing overall effectiveness and reducing negative off-target effects. The immunoproteasome-specific inhibitor, IPSI-001, was shown to have inhibitory preference over the constitutive proteasome, and display enhanced efficiency of apoptotic induction of tumor cells from a hematologic origin. Herein, we discuss the preclinical and clinical development of carfilzomib and explore the potential of immunoproteasome-specific inhibitors, like IPSI-001, as a rational approach to exclusively target hematological malignancies.
The proteasome is a multicatalytic proteinase complex responsible for the degradation of most intracellular proteins, including
proteins crucial to cell cycle regulation and programmed cell death, or ...apoptosis. In preclinical cancer models, proteasome
inhibitors induce apoptosis, have in vivo antitumor efficacy, and sensitize malignant cells and tumors to the proapoptotic effects of conventional chemotherapeutics
and radiation therapy. Interestingly, transformed cells display greater susceptibility to proteasome inhibition than nonmalignant
cells. Therefore, proteasome inhibition holds promise as a novel approach to the treatment of cancer. Inhibitors of the proteasome
impact on cells in part through down-regulation of nuclear factor κB, but also through modulation of cell cycle proteins and
other pro- and antiapoptotic pathways. Bortezomib (VELCADE; formerly PS-341), the first such inhibitor to undergo clinical
testing, has demonstrated impressive antitumor activity and manageable toxicities in Phase I and II trials both as a single
agent, and in combination with other drugs. It has been approved recently by the Food and Drug Administration for therapy
of patients with multiple myeloma who have received at least two prior regimens and progressed on the last of these. Ongoing
preclinical evaluations of the mechanisms that underlie the antitumor effects of proteasome inhibitors, and clinical trials
in a variety of tumor types, will allow additional refinement of the role these agents will play in cancer therapy. Below
we discuss the rationale behind targeting the proteasome for cancer therapy, and review the preclinical and clinical data
on proteasome inhibitors alone, and in combination with conventional chemotherapeutics.
Resistance of myeloma to lenalidomide is an emerging clinical problem, and though it has been associated in part with activation of Wnt/β-catenin signaling, the mediators of this phenotype remained ...undefined. Lenalidomide-resistant models were found to overexpress the hyaluronan (HA)-binding protein CD44, a downstream Wnt/β-catenin transcriptional target. Consistent with a role of CD44 in cell adhesion-mediated drug resistance (CAM-DR), lenalidomide-resistant myeloma cells were more adhesive to bone marrow stroma and HA-coated plates. Blockade of CD44 with monoclonal antibodies, free HA or CD44 knockdown reduced adhesion and sensitized to lenalidomide. Wnt/β-catenin suppression by FH535 enhanced the activity of lenalidomide, as did interleukin-6 neutralization with siltuximab. Notably, all-trans retinoic acid (ATRA) downregulated total β-catenin, cell-surface and total CD44, reduced adhesion of lenalidomide-resistant myeloma cells and enhanced the activity of lenalidomide in a lenalidomide-resistant in vivo murine xenograft model. Finally, ATRA sensitized primary myeloma samples from patients that had relapsed and/or refractory disease after lenalidomide therapy to this immunomodulatory agent ex vivo. Taken together, our findings support the hypotheses that CD44 and CAM-DR contribute to lenalidomide resistance in multiple myeloma, that CD44 should be evaluated as a putative biomarker of sensitivity to lenalidomide, and that ATRA or other approaches that target CD44 may overcome clinical lenalidomide resistance.
Tumor lysis syndrome (TLS) is a life-threatening disorder characterized by hyperuricemia and metabolic derangements. The efficacy of rasburicase, administered daily for 5 days, has been well ...established. However, the optimal duration of therapy is unknown in adults.
We evaluated the efficacy of rasburicase (0.15 mg/kg) administered as single dose followed by as needed dosing (maximum five doses) versus daily dosing for 5 days in adult patients at risk for TLS.
Eighty of the 82 patients enrolled received rasburicase; 40 high risk median uric acid (UA) 8.5 mg/dl; range, 1.5–19.7 and 40 potential risk (UA = 5.6 mg/dl; range, 2.4–7.4). Seventy-nine patients (99%) experienced normalization in their UA within 4 h after the first dose; 84% to an undetectable level (<0.7 mg/dl). Thirty-nine of 40 (98%) patients in the daily-dose arm and 34 of 40 (85%) patients in single-dose arm showed sustained UA response. Six high-risk patients within the single-dose arm required second dose for UA >7.5 mg/dl. Rasburicase was well tolerated; one patient with glucose-6-phosphate dehydrogenase deficiency developed methemoglobinemia and hemolysis.
Rasburicase is highly effective for prevention and management of hyperuricemia in adults at risk for TLS. Single-dose rasburicase was effective in most patients; only a subset of high-risk patients required a second dose.
In the primary analysis of the phase 3 MAIA trial (median follow-up 28·0 months), a significant improvement in progression-free survival was observed with daratumumab plus lenalidomide and ...dexamethasone versus lenalidomide and dexamethasone alone in transplantation-ineligible patients with newly diagnosed multiple myeloma. Here, we report the updated efficacy and safety results from a prespecified interim analysis for overall survival.
MAIA is an ongoing, multicentre, randomised, open-label, phase 3 trial that enrolled patients at 176 hospitals in 14 countries across North America, Europe, the Middle East, and the Asia-Pacific region. Eligible patients were aged 18 years or older, had newly diagnosed multiple myeloma, had an Eastern Cooperative Oncology Group performance status score of 0–2, and were ineligible for high-dose chemotherapy with autologous stem-cell transplantation because of their age (≥65 years) or comorbidities. Patients were randomly assigned (1:1) using randomly permuted blocks (block size 4) by an interactive web response system to receive 28-day cycles of intravenous daratumumab (16 mg/kg, once per week during cycles 1–2, once every 2 weeks in cycles 3–6, and once every 4 weeks thereafter) plus oral lenalidomide (25 mg on days 1–21 of each cycle) and oral dexamethasone (40 mg on days 1, 8, 15, and 22 of each cycle; daratumumab group) or lenalidomide and dexamethasone alone (control group). Randomisation was stratified by International Staging System disease stage, geographical region, and age. Neither patients nor investigators were masked to treatment assignment. The primary endpoint was progression-free survival, which was centrally assessed, and a secondary endpoint was overall survival (both assessed in the intention-to-treat population). The safety population included patients who received at least one dose of the study treatment. The results presented here are from a prespecified interim analysis for overall survival, for which the prespecified stopping boundary was p=0·0414. This trial is registered with ClinicalTrials.gov, NCT02252172.
Between March 18, 2015, and Jan 15, 2017, 952 patients were assessed for eligibility, of whom 737 patients were enrolled and randomly assigned to the daratumumab group (n=368) or the control group (n=369). At a median follow-up of 56·2 months (IQR 52·7–59·9), median progression-free survival was not reached (95% CI 54·8–not reached) in the daratumumab group versus 34·4 months (29·6–39·2) in the control group (hazard ratio HR 0·53 95% CI 0·43–0·66; p<0·0001). Median overall survival was not reached in either group (daratumumab group, 95% CI not reached–not reached; control group, 95% CI 55·7–not reached; HR 0·68 95% CI 0·53–0·86; p=0·0013). The most common (>15%) grade 3 or higher treatment-emergent adverse events were neutropenia (197 54% patients in the daratumumab group vs 135 37% patients in the control group), pneumonia (70 19% vs 39 11%), anaemia (61 17% vs 79 22%), and lymphopenia (60 16% vs 41 11%). Serious adverse events occurred in 281 (77%) patients in the daratumumab group and 257 (70%) patients in the control group. Treatment-related deaths occurred in 13 (4%) patients in the daratumumab group and ten (3%) patients in the control group.
Daratumumab plus lenalidomide and dexamethasone increased overall survival and progression-free survival in patients ineligible for stem-cell transplantation with newly diagnosed multiple myeloma. There were no new safety concerns. Our results support the frontline use of daratumumab plus lenalidomide and dexamethasone for patients with multiple myeloma who are ineligible for transplantation.
Janssen Research & Development.
The incidence of venous thromboembolism (VTE) is more than 1 per thousand annually in the general population and increases further in cancer patients. The risk of VTE is higher in multiple myeloma ...(MM) patients who receive thalidomide or lenalidomide, especially in combination with dexamethasone or chemotherapy. Various VTE prophylaxis strategies, such as low-molecular-weight heparin (LMWH), warfarin or aspirin, have been investigated in small, uncontrolled clinical studies. This manuscript summarizes the available evidence and recommends a prophylaxis strategy according to a risk-assessment model. Individual risk factors for thrombosis associated with thalidomide/lenalidomide-based therapy include age, history of VTE, central venous catheter, comorbidities (infections, diabetes, cardiac disease), immobilization, surgery and inherited thrombophilia. Myeloma-related risk factors include diagnosis and hyperviscosity. VTE is very high in patients who receive high-dose dexamethasone, doxorubicin or multiagent chemotherapy in combination with thalidomide or lenalidomide, but not with bortezomib. The panel recommends aspirin for patients with < or = 1 risk factor for VTE. LMWH (equivalent to enoxaparin 40 mg per day) is recommended for those with two or more individual/myeloma-related risk factors. LMWH is also recommended for all patients receiving concurrent high-dose dexamethasone or doxorubicin. Full-dose warfarin targeting a therapeutic INR of 2-3 is an alternative to LMWH, although there are limited data in the literature with this strategy. In the absence of clear data from randomized studies as a foundation for recommendations, many of the following proposed strategies are the results of common sense or derive from the extrapolation of data from many studies not specifically designed to answer these questions. Further investigation is needed to define the best VTE prophylaxis.
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