Prognostic impact of immunoparesis at diagnosis and after treatment onset in patients with light-chain amyloidosis

OBJECTIVES

Immunoparesis (IP) is a risk factor associated with an unfavourable outcome in several plasma cell disorders. It has been suggested that its presence in light-chain (AL) amyloidosis could be associated with worse prognosis. However, the relevance of IP after treatment has not been evaluated to date. The aim of this study was to determine the prognostic impact of IP at diagnosis and one year after treatment onset in patients with AL amyloidosis.

METHODS

The clinical records of 69 patients with AL amyloidosis treated at a single institution from January 2006 to January 2016 were included in the study.

RESULTS

IP was observed in 27.5% of patients at diagnosis. The presence of IP was associated with a lower probability to achieve very good partial response or better after first-line treatment (37.8% versus 62.2%; p = .04). However, only in the group of patients treated with autologous stem cell transplantation (ASCT), the presence of IP resulted in a shorter progression-free survival (PFS) (30.2 months versus not reached [NR]; p = .02) but not in overall survival (OS). Persistence of IP at one year after treatment onset was identified in only four (9.8%) of the 41 evaluable patients. In the ASCT group, the absence of IP at one year after treatment onset resulted in a longer median PFS and OS (NR versus 22.6 months; p = .006; and NR versus 35.2 months; p < .001; respectively). In the multivariate analysis, the absence of IP at one year after treatment onset was independently associated with longer survival.

CONCLUSION

IP at diagnosis has a negative impact on survival while its absence at one year after treatment is an independent marker for long-term survival.

The BET bromodomain inhibitor CPI203 improves lenalidomide and dexamethasone activity in in vitro and in vivo models of multiple myeloma by blockade of Ikaros and MYC signaling

Most patients with multiple myeloma treated with current therapies, including immunomodulatory drugs, eventually develop relapsed/refractory disease. Clinical activity of lenalidomide relies on degradation of Ikaros and the consequent reduction in IRF4 expression, both required for myeloma cell survival and involved in the regulation of MYC transcription. Thus, we sought to determine the combinational effect of an MYC-interfering therapy with lenalidomide/dexamethasone. We analyzed the potential therapeutic effect of the combination of the BET bromodomain inhibitor CPI203 with the lenalidomide/dexamethasone regimen in myeloma cell lines. CPI203 exerted a dose-dependent cell growth inhibition in cell lines, indeed in lenalidomide/dexamethasone-resistant cells (median response at 0.5 μM: 65.4%), characterized by G1 cell cycle blockade and a concomitant inhibition of MYC and Ikaros signaling. These effects were potentiated by the addition of lenalidomide/dexamethasone. Results were validated in primary plasma cells from patients with multiple myeloma co-cultured with the mesenchymal stromal cell line stromaNKtert. Consistently, the drug combination evoked a 50% reduction in cell proliferation and correlated with basal Ikaros mRNA expression levels (P=0.04). Finally, in a SCID mouse xenotransplant model of myeloma, addition of CPI203 to lenalidomide/dexamethasone decreased tumor burden, evidenced by a lower glucose uptake and increase in the growth arrest marker GADD45B, with simultaneous downregulation of key transcription factors such as MYC, Ikaros and IRF4. Taken together, our data show that the combination of a BET bromodomain inhibitor with a lenalidomide-based regimen may represent a therapeutic approach to improve the response in relapsed/refractory patients with multiple myeloma, even in cases with suboptimal prior response to immunomodulatory drugs.

International Myeloma Working Group consensus criteria for response and minimal residual disease assessment in multiple myeloma

Treatment of multiple myeloma has substantially changed over the past decade with the introduction of several classes of new effective drugs that have greatly improved the rates and depth of response. Response criteria in multiple myeloma were developed to use serum and urine assessment of monoclonal proteins and bone marrow assessment (which is relatively insensitive). Given the high rates of complete response seen in patients with multiple myeloma with new treatment approaches, new response categories need to be defined that can identify responses that are deeper than those conventionally defined as complete response. Recent attempts have focused on the identification of residual tumour cells in the bone marrow using flow cytometry or gene sequencing. Furthermore, sensitive imaging techniques can be used to detect the presence of residual disease outside of the bone marrow. Combining these new methods, the International Myeloma Working Group has defined new response categories of minimal residual disease negativity, with or without imaging-based absence of extramedullary disease, to allow uniform reporting within and outside clinical trials. In this Review, we clarify several aspects of disease response assessment, along with endpoints for clinical trials, and highlight future directions for disease response assessments.

Prognostic impact of circulating plasma cells in patients with multiple myeloma: implications for plasma cell leukemia definition

The presence of circulating plasma cells in patients with multiple myeloma is considered a marker for highly proliferative disease. In the study herein, the impact of circulating plasma cells assessed by cytology on survival of patients with multiple myeloma was analyzed. Wright-Giemsa stained peripheral blood smears of 482 patients with newly diagnosed myeloma or plasma cell leukemia were reviewed and patients were classified into 4 categories according to the percentage of circulating plasma cells: 0%, 1–4%, 5–20%, and plasma cell leukemia with the following frequencies: 382 (79.2%), 83 (17.2%), 12 (2.5%) and 5 (1.0%), respectively. Median overall survival according to the circulating plasma cells group was 47, 50, 6 and 14 months, respectively. At multivariate analysis, the presence of 5 to 20% circulating plasma cells was associated with a worse overall survival (relative risk 4.9, 95% CI 2.6–9.3) independently of age, creatinine, the Durie-Salmon system stage and the International Staging System (ISS) stage. Patients with ≥5% circulating plasma cells had lower platelet counts (median 86×10⁹/L vs. 214×10⁹/L, P<0.0001) and higher bone marrow plasma cells (median 53% vs. 36%, P=0.004). The presence of ≥5% circulating plasma cells in patients with multiple myeloma has a similar adverse prognostic impact as plasma cell leukemia.

Next Generation Flow for highly sensitive and standardized detection of minimal residual disease in multiple myeloma

Flow cytometry has become a highly valuable method to monitor minimal residual disease (MRD) and evaluate the depth of complete response (CR) in bone marrow (BM) of multiple myeloma (MM) after therapy. However, current flow-MRD has lower sensitivity than molecular methods and lacks standardization. Here we report on a novel next generation flow (NGF) approach for highly sensitive and standardized MRD detection in MM. An optimized 2-tube 8-color antibody panel was constructed in five cycles of design-evaluation-redesign. In addition, a bulk-lysis procedure was established for acquisition of ⩾10⁷ cells/sample, and novel software tools were constructed for automatic plasma cell gating. Multicenter evaluation of 110 follow-up BM from MM patients in very good partial response (VGPR) or CR showed a higher sensitivity for NGF-MRD vs conventional 8-color flow-MRD -MRD-positive rate of 47 vs 34% (P=0.003)-. Thus, 25% of patients classified as MRD-negative by conventional 8-color flow were MRD-positive by NGF, translating into a significantly longer progression-free survival for MRD-negative vs MRD-positive CR patients by NGF (75% progression-free survival not reached vs 7 months; P=0.02). This study establishes EuroFlow-based NGF as a highly sensitive, fully standardized approach for MRD detection in MM which overcomes the major limitations of conventional flow-MRD methods and is ready for implementation in routine diagnostics.

Absence of spontaneous response improvement beyond day +100 after autologous stem cell transplantation in multiple myeloma

The response evaluation after autologous stem-cell transplantation (ASCT) is usually performed at day +100 in patients with multiple myeloma (MM). A recent report suggests that improvement in the response can be observed beyond day +100. The aim of the present study has been to evaluate the rate of improved response and outcome beyond day +100 after ASCT, with and without maintenance therapy. One hundred and forty-four patients who underwent single ASCT with chemosensitive disease and achieved less than CR at day 100 post ASCT were evaluated. Seventy-four patients (51.4%) did not receive any maintenance with only one of them showing an upgrade in the response. The remaining 70 patients (48.6%) received maintenance therapy; eleven of them (15.7%) improved their response beyond day +100. The outcome of these patients was better than those who did not upgrade their response in both progression-free survival and overall survival (P=0.019 and P=0.031, respectively). In conclusion, the improvement in response beyond day +100 after ASCT in patients not receiving any therapy is exceedingly rare. A minority of patients receiving maintenance therapy after ASCT upgrades their response and this finding is associated with better outcome.

A Next-Generation Sequencing Strategy for Evaluating the Most Common Genetic Abnormalities in Multiple Myeloma

Identification and characterization of genetic alterations are essential for diagnosis of multiple myeloma and may guide therapeutic decisions. Currently, genomic analysis of myeloma to cover the diverse range of alterations with prognostic impact requires fluorescence in situ hybridization (FISH), single nucleotide polymorphism arrays, and sequencing techniques, which are costly and labor intensive and require large numbers of plasma cells. To overcome these limitations, we designed a targeted-capture next-generation sequencing approach for one-step identification of IGH translocations, V(D)J clonal rearrangements, the IgH isotype, and somatic mutations to rapidly identify risk groups and specific targetable molecular lesions. Forty-eight newly diagnosed myeloma patients were tested with the panel, which included IGH and six genes that are recurrently mutated in myeloma: NRAS, KRAS, HRAS, TP53, MYC, and BRAF. We identified 14 of 17 IGH translocations previously detected by FISH and three confirmed translocations not detected by FISH, with the additional advantage of breakpoint identification, which can be used as a target for evaluating minimal residual disease. IgH subclass and V(D)J rearrangements were identified in 77% and 65% of patients, respectively. Mutation analysis revealed the presence of missense protein-coding alterations in at least one of the evaluating genes in 16 of 48 patients (33%). This method may represent a time- and cost-effective diagnostic method for the molecular characterization of multiple myeloma.

Final overall survival results of a randomized trial comparing bortezomib plus pegylated liposomal doxorubicin with bortezomib alone in patients with relapsed or refractory multiple myeloma

BACKGROUND

Previous results from an interim analysis of an open-label, randomized, phase 3 study demonstrated that bortezomib combined with pegylated liposomal doxorubicin (PLD) was superior to bortezomib monotherapy in patients with relapsed/refractory multiple myeloma who had previously received one or more lines of therapy. Protocol-defined final survival data from that study are provided here.

METHODS

Patients were randomized (1:1) to receive either bortezomib alone (1.3 mg/m(2) intravenously on days 1, 4, 8, and 11 of every 21-day cycle) or bortezomib-PLD (bortezomib plus PLD 30 mg/m(2) intravenously on day 4). The primary endpoint was the time to progression. Secondary efficacy endpoints included overall survival (OS), progression-free survival, and the overall response rate.

RESULTS

In total, 646 patients (bortezomib-PLD, n = 324; bortezomib alone, n = 322) were randomized between December, 2004, and March, 2006. On the clinical cutoff date (May 16, 2014) for the final survival analysis, at a median follow-up of 103 months, 79% of patients had died (bortezomib-PLD group: 253 of 324 patients; 78%; bortezomib alone group: 257 of 322 patients; 80%). The median OS in the bortezomib-PLD group was 33 months (95% confidence interval [CI], 28.9-37.1) versus 30.8 months (95% CI, 25.2-36.5) in the bortezomib alone group (hazard ratio, 1.047; 95% CI, 0.879-1.246; P = .6068). Salvage therapies included conventional and novel drugs, which were well balanced between the two treatment groups.

CONCLUSIONS

Despite inducing a superior time to progression, long-term follow-up revealed that PLD-bortezomib did not improve OS compared with bortezomib alone in patients with relapsed/refractory multiple myeloma. The inability to sustain the early observed survival advantage may have been caused by the effects of subsequent lines of therapy, and underscores the need for long-term follow-up of phase 3 trials while recognizing the challenge of having adequate power to detect long-term differences in OS. Cancer 2016;122:2050-6. © 2016 American Cancer Society.

Daratumumab monotherapy in patients with treatment-refractory multiple myeloma (SIRIUS): an open-label, randomised, phase 2 trial

BACKGROUND

New treatment options are needed for patients with multiple myeloma that is refractory to proteasome inhibitors and immunomodulatory drugs. We assessed daratumumab, a novel CD38-targeted monoclonal antibody, in patients with refractory multiple myeloma.

METHODS

In this open-label, multicentre, phase 2 trial done in Canada, Spain, and the USA, patients (age ≥18 years) with multiple myeloma who were previously treated with at least three lines of therapy (including proteasome inhibitors and immunomodulatory drugs), or were refractory to both proteasome inhibitors and immunomodulatory drugs, were randomly allocated in a 1:1 ratio to receive intravenous daratumumab 8 mg/kg or 16 mg/kg in part 1 stage 1 of the study, to decide the dose for further assessment in part 2. Patients received 8 mg/kg every 4 weeks, or 16 mg/kg per week for 8 weeks (cycles 1 and 2), then every 2 weeks for 16 weeks (cycles 3-6), and then every 4 weeks thereafter (cycle 7 and higher). The allocation schedule was computer-generated and randomisation, with permuted blocks, was done centrally with an interactive web response system. In part 1 stage 2 and part 2, patients received 16 mg/kg dosed as in part 1 stage 1. The primary endpoint was overall response rate (partial response [PR] + very good PR + complete response [CR] + stringent CR). All patients who received at least one dose of daratumumab were included in the analysis. The trial is registered with ClinicalTrials.gov, number NCT01985126.

FINDINGS

The study is ongoing. In part 1 stage 1 of the study, 18 patients were randomly allocated to the 8 mg/kg group and 16 to the 16 mg/kg group. Findings are reported for the 106 patients who received daratumumab 16 mg/kg in parts 1 and 2. Patients received a median of five previous lines of therapy (range 2-14). 85 (80%) patients had previously received autologous stem cell transplantation, 101 (95%) were refractory to the most recent proteasome inhibitors and immunomodulatory drugs used, and 103 (97%) were refractory to the last line of therapy. Overall responses were noted in 31 patients (29.2%, 95% CI 20.8-38.9)-three (2.8%, 0.6-8.0) had a stringent CR, ten (9.4%, 4.6-16.7) had a very good PR, and 18 (17.0%, 10.4-25.5) had a PR. The median time to first response was 1.0 month (range 0.9-5.6). Median duration of response was 7.4 months (95% CI 5.5-not estimable) and progression-free survival was 3.7 months (95% CI 2.8-4.6). The 12-month overall survival was 64.8% (95% CI 51.2-75.5) and, at a subsequent cutoff, median overall survival was 17.5 months (95% CI 13.7-not estimable). Daratumumab was well tolerated; fatigue (42 [40%] patients) and anaemia (35 [33%]) of any grade were the most common adverse events. No drug-related adverse events led to treatment discontinuation.

INTERPRETATION

Daratumumab monotherapy showed encouraging efficacy in heavily pretreated and refractory patients with multiple myeloma, with a favourable safety profile in this population of patients.

FUNDING

Janssen Research & Development.

Bendamustine, bortezomib and prednisone for the treatment of patients with newly diagnosed multiple myeloma: results of a prospective phase 2 Spanish/PETHEMA trial

Bendamustine is a bifunctional alkylating agent with proven activity in myeloma. In this study 60 newly diagnosed myeloma patients were given bendamustine plus bortezomib and prednisone in a regimen consisting of one cycle of bortezomib twice weekly for 6 weeks (1.3 mg/m(2) on days 1, 4, 8, 11, 22, 25, 29, and 32), plus bendamustine (90 mg/m(2) on days 1 and 4) and prednisone. The following cycles included bortezomib once weekly. Patients who were transplant candidates proceeded to stem cell collection after four cycles and the transplant was performed after six cycles. Patients who were not candidates for transplantation received up to nine cycles. Forty-two patients were transplant candidates and after six cycles, 50% achieved at least a very good partial response, with 24% having complete responses; 35 proceeded to a transplant, and the complete response rate was 54%. Seventeen patients continued up to nine cycles, and 57% achieved at least a very good partial response, including 26% with complete responses. The 2-year progression-free survival and overall survival rates were 62% and 86%, respectively. The safety profile was manageable, but stem cell mobilization was compromised in 35% of patients. In summary, this combination is effective in untreated patients, with an acceptable toxicity profile, but given the introduction of second-generation novel agents and monoclonal antibodies, the combination will probably be better reserved for relapsing patients, in whom stem cell collection is not needed, while cost-effective combinations with non-cross-resistant drugs continue to represent a medical need. This trial was registered with ClinicalTrials.gov, number NCT01376401.

Treatment for patients with newly diagnosed multiple myeloma in 2015

Multiple myeloma is the second most frequent haematological disease. The introduction of high-dose melphalan followed by autologous haematopoietic cell transplant (HDT/ASCT) for young patients and the availability of novel agents for young and elderly patients with multiple myeloma have dramatically changed the perspective of treatment. However, further research is necessary if we want to definitively cure the disease. Treatment goals for transplant-eligible and non-transplant-eligible patients should be to prolong survival by achieving the best possible response, while ensuring quality of life. The treatment should be individualized on the basis of host and disease features and better monitoring of the response upon use of high-sensitivity techniques for evaluating residual disease. For young patients, HDT/ASCT is a standard of care for treatment and its efficacy has been enhanced and challenged by the new drugs. For elderly patients, treatment options were limited to alkylators, but new upfront treatment combinations based on novel agents (proteasome inhibitors and immunomodulatory drugs) combined or not with alkylators have significantly improved outcomes.Extended treatment for young and elderly patients improves the quality and duration of clinical responses; however,the optimal scheme, appropriate doses and duration of long-term therapy have not yet been fully determined.This review summarises the progress in the treatment of patients with newly diagnosed multiple myeloma, addressing critical questions such as the optimal induction, early versus late ASCT, consolidation and/or maintenance for young patients, and how we can choose the best option for non-transplant-eligible patients.

A phase II trial of lenalidomide, dexamethasone and cyclophosphamide for newly diagnosed patients with systemic immunoglobulin light chain amyloidosis

Immunomodulatory drugs have been shown to be of benefit in relapsed/refractory immunoglobulin light-chain (AL) amyloidosis. We designed a prospective, multicentre phase II trial of lenalidomide, dexamethasone and cyclophosphamide for newly diagnosed patients with AL amyloidosis not eligible for autologous stem-cell transplantation. Twenty-eight patients were included in the study. Cardiac involvement was present in 23 patients; 14 of them had cardiac stage III. The overall haematological response rate was 46%, including complete and very good partial responses in 25% and 18% of patients respectively. Haematological response was mainly associated with absence of cardiac stage III and lower tumour burden. Organ response was observed in 46% of patients. After a median follow-up of 24 months, median progression-free and overall survival have not been reached, both being significantly longer in responders (P < 0·001 and P = 0·001 respectively). Seventeen patients have discontinued treatment, mostly due to amyloid-related death, disease progression or lack of response. Only 14% of the patients discontinued treatment due to therapy-related adverse events. Our results support the efficacy of this regimen, with high quality responses and prolonged survival, as well as its tolerability, in patients with AL amyloidosis not eligible for stem cell transplant and without advanced cardiac involvement (clinicaltrials.gov identifier: NCT01194791).

Allogeneic hematopoietic SCT in multiple myeloma: long-term results from a single institution

The role of allogeneic hematopoietic SCT (allo-HCT) in multiple myeloma (MM) remains controversial. A total of 58 patients received an allo-HCT (25 of them with myeloablative conditioning-allo-MAC-and 33 with reduced-intensity conditioning-allo-RIC) at our institution over a 28-year period. The CR rate for allo-MAC was 36%. The incidence of grade III-IV acute GVHD (aGVHD) and chronic GVHD (cGVHD) was 28% and 39%, respectively The TRM at any time was 60% and the main causes of death were aGVHD or infectious complications not directly related to GVHD. The estimated PFS and OS at 15 years were 8% and 15%, respectively. The CR rate with allo-RIC was 45%. The incidence of grade III-IV aGVHD and cGVHD were 24% and 41%, respectively. The TRM at any time was 33% and was mainly related to aGVHD. The estimated PFS and OS at 5 years were 22% and 38%, respectively. Despite its high TRM, a proportion of patients with high-risk myeloma (early relapse and newly diagnosed ultrahigh risk) may obtain long-term disease control with allo-HCT. New approaches aimed at decreasing the incidence of aGVHD, and consequently to decrease the TRM, are needed.

A phase 2, randomized, double-blind, placebo-controlled study of siltuximab (anti-IL-6 mAb) and bortezomib versus bortezomib alone in patients with relapsed or refractory multiple myeloma

We compared the safety and efficacy of siltuximab (S), an anti-interleukin-6 chimeric monoclonal antibody, plus bortezomib (B) with placebo (plc) + B in patients with relapsed/refractory multiple myeloma in a randomized phase 2 study. Siltuximab was given by 6 mg/kg IV every 2 weeks. On progression, B was discontinued and high-dose dexamethasone could be added to S/plc. Response and progression-free survival (PFS) were analyzed pre-dexamethasone by European Group for Blood and Marrow Transplantation (EBMT) criteria. For the 281 randomized patients, median PFS for S + B and plc + B was 8.0 and 7.6 months (HR 0.869, P = 0.345), overall response rate was 55 versus 47% (P = 0.213), complete response rate was 11 versus 7%, and median overall survival (OS) was 30.8 versus 36.8 months (HR 1.353, P = 0.103). Sustained suppression of C-reactive protein, a marker reflective of inhibition of interleukin-6 activity, was seen with S + B. Siltuximab did not affect B pharmacokinetics. Siltuximab/placebo discontinuation (75 versus 66%), grade ≥3 neutropenia (49 versus 29%), thrombocytopenia (48 versus 34%), and all-grade infections (62 versus 49%) occurred more frequently with S + B. The addition of siltuximab to bortezomib did not appear to improve PFS or OS despite a numerical increase in response rate in patients with relapsed or refractory multiple myeloma.

Long-term follow-up from a phase 1/2 study of single-agent bortezomib in relapsed systemic AL amyloidosis

CAN2007 was a phase 1/2 study of once- and twice-weekly single-agent bortezomib in relapsed primary systemic amyloid light chain amyloidosis (AL) amyloidosis. Seventy patients were treated, including 18 and 34 patients at the maximum planned doses on the once- and twice-weekly schedules. This prespecified final analysis provides mature response and long-term outcomes data after 3-year additional follow-up since the last report. In the once-weekly 1.6 mg/m(2) and twice-weekly 1.3 mg/m(2) bortezomib groups, final hematologic response rates were 68.8% and 66.7%; 80% of patients in each group sustained their response for ≥1 year. One-year progression-free rates were 72.2% and 76.8%. Median overall survival (OS) was 62.1 months and not reached; 4-year OS rates were 75.0% and 63.0%. Low baseline difference in κ/λ free light-chain level was associated with higher hematologic complete response rates and longer OS. At data cutoff, 40 (57%) patients had received subsequent therapy, including 19 (27%) retreated with bortezomib, 11 (58%) of whom achieved complete or partial hematologic responses. Four patients received prolonged bortezomib for between 3.5 and 5.6 years, with no new safety concerns, highlighting the feasibility of long-term therapy. Single-agent bortezomib produced durable hematologic responses and promising long-term OS in relapsed AL amyloidosis. This trial was registered at www.clinicaltrials.gov as #NCT00298766.