NK and T-lymphocyte Kinetics Predict Outcome in Myeloma Patients Treated With Elotuzumab, Lenalidomide Plus Dexamethasone.

Background/Aim: Elotuzumab, an anti-SLAMF7 monoclonal antibody, can enhance immune activity via elevated antibody-dependent cellular cytotoxicity and reduced SLAMF7+CD8+CD57+ regulatory T-cells (Tregs). This multicenter observational study investigated the kinetics of lymphocytes in myeloma patients treated with elotuzumab, lenalidomide, and dexamethasone (ERd) by two-color flow cytometry using peripheral blood samples. Patients and Methods: Twenty-one patients were included in this study. The median duration of ERd was 22.6 months, and the cutoff time for long-duration ERd was two years. Results: The CD2+CD16+ and CD16+CD57- NK cells were significantly increased over time in the long-duration ERd group compared to those in the short-duration ERd group (p=0.035 and p<0.001). The CD8+ and CD16-CD57+ lymphocytes, identified as low-activity NK cells or SLAMF7+ Tregs, were significantly increased in the patients whose ERd outcome was progressive disease (PD) compared to those in the non-PD group (p=0.023 and p<0.001). The mean CD4/CD8 ratio and CD19+ lymphocyte counts in the long-duration ERd group were significantly lower than those in the short-duration ERd group, although the kinetics of them did not change over time (p=0.016 and p=0.011). When the cutoff value of CD4/CD8 ratio was 0.792 according to ROC curves, the two-year time to next treatment (TTNT) in the low CD4/CD8 group was significantly longer than that in the high CD4/CD8 group (80.0% vs. 15.0%, p=0.024). Conclusion: The change in NK cells and CD8+ Tregs predicted long-duration ERd and PD, and maintaining low CD4/8 ratio predicted long TTNT, suggesting that these lymphocyte fractions might be biomarkers for a durable therapeutic effect of ERd in myeloma patients.

Autologous HSCT with novel agent-based induction and consolidation followed by lenalidomide maintenance for untreated multiple myeloma.

Triplet regimen comprising proteasome inhibitors, immunomodulatory drugs, and dexamethasone (DEX) is a recommended induction/consolidation therapy for multiple myeloma (MM) patients eligible for transplant. In this Japanese phase II study conducted from 2017 to 2019, newly diagnosed MM patients aged 20-65 received four induction cycles with bortezomib (Bor), lenalidomide (Len), and DEX (VRD), followed by Bor and high-dose melphalan with autologous stem cell rescue. Subsequently, they underwent four consolidation cycles with carfilzomib, Len, and DEX (KRD), followed by Len maintenance until disease progression. A total of 141 patients were analyzed. In an intent-to-treat population, the complete or better response post induction was 19.9%, rising to 39.7%, 58.9%, and 62.4% after transplant, consolidation, and 1-year maintenance, respectively. With a median follow-up of 38 months, the 3-year progression-free survival (PFS) rate was 83.5% and the 3-year overall survival rate was 92.5%. Severe adverse events (≥grade 3) occurred in ~30% of patients; however, there was no treatment-related mortality. These findings clearly showed the tolerability and effectiveness of this protocol. Nevertheless, patients with high-risk cytogenetics showed a trend toward lower 3-year PFS than those without (77.8% vs. 89.4%, p = 0.051), and ultra-high-risk cytogenetics (≥2 high-risk cytogenetics) had an even worse prognosis, with 61.2% 3-year PFS. To overcome this situation, a more potent treatment strategy incorporating novel agents such as the CD38-antibody should be assessed in future studies.

Efficacy and Safety of Ixazomib Plus Lenalidomide and Dexamethasone Following Injectable PI-Based Therapy in Relapsed/Refractory Multiple Myeloma.

This nationwide, multicenter, open-label, single-arm study evaluated the efficacy and safety of the oral proteasome inhibitor (PI), ixazomib plus lenalidomide (LEN) and dexamethasone (DEX) (IRd) following injectable PI-based therapy for relapsed/refractory multiple myeloma (RRMM). Of 45 patients enrolled, 36 patients received IRd after achieving at least a minor response to 3 cycles of bortezomib or carfilzomib plus LEN + DEX (VRd, n=6; KRd, n=30). At median follow-up of 20.8 months, the 12-month event-free survival rate (primary endpoint) was 49% (90% CI: 35.9-62.0), counting 11 events of progressive disease/death, 8 dropouts and 4 missing response data. The 12-month progression-free survival (PFS) rate by Kaplan-Meier analysis (dropouts as censoring) was 74% (95% CI: 56-86). Median PFS and time to next treatment (95% CI) were 29.0 (21.3-NE) and 32.3 (14.9-35.4) months, respectively; median OS was not evaluable. The overall response rate was 73%, and 42% of patients had a very good partial response or better. Frequent (≥10% incidence) grade ≥3 treatment emergent adverse events were decreased neutrophil and platelet counts (n=7 [16%] each). Two deaths occurred (one during KRd treatment and one during IRd treatment), both due to pneumonia. IRd following injectable PI-based therapy was tolerable and efficacious in RRMM patients. TRIAL REGISTRATION NUMBER: NCT03416374; Date of registration: January 31, 2018.

Eight-color multiparameter flow cytometry (EuroFlow-NGF) is as sensitive as next-generation sequencing in detecting minimal/measurable residual disease in autografts of patients with multiple myeloma.

The prognostic value of minimal/measurable residual disease (MRD) detection in autografts of patients with multiple myeloma (MM) in an autologous stem-cell transplantation setting has been reported. Next-generation flow (NGF) cytometry has lower sensitivity (2 × 10-6) to detect MRD than next-generation sequencing (NGS) (<10-6). We compared the clinical value of high-sensitivity NGF (cutoff: <10-6) and NGS (cutoff: 10-6) for the detection of MRD in the cryopreserved autografts of 49 patients with newly diagnosed MM. The sensitivity test using frozen/thawed autografts revealed a strong correlation among MRD levels of 5 × 10-7 and 1 × 10-4 (r = 0.9997, p < 0.0001) when an adequate number of cells were analyzed. Autograft MRD levels determined using NGF and NGS were highly correlated (r = 0.811, p < 0.0001). MRD-negative patients identified with NGF (cutoff: <10-6) showed significantly longer progression-free survival (PFS) than MRD-positive patients (p = 0.026). The PFS of MRD-negative patients determined by NGS (cutoff: 10-6) was similar to that determined by NGF. These results show that the high-sensitivity NGF method can assess MRD in frozen/thawed autografts, and its prognostic value is comparable to that of NGS.

Once Monthly Elotuzumab and Lenalidomide Plus Dexamethasone for Multiple Myeloma: A Multicenter Observation Study.

INTRODUCTION: Elotuzumab and lenalidomide plus dexamethasone (ERd) is a standard salvage chemotherapy for multiple myeloma, and elotuzumab is commonly administered every 2 weeks after cycle 3 (conventional ERd). Alternatively, elotuzumab may often be used every 4 weeks (monthly ERd) in real-world practice. The purpose of this multicenter observational study was to investigate the efficacy and tolerability of monthly ERd. METHODS: We investigated the efficacy and tolerability between conventional and monthly ERd regimens for the myeloma patients in six institutes retrospectively. RESULTS: Seventy-five patients were included in this study. The median patient age was 68 years. The median number of prior chemotherapies was two (1-5). The number of patients with prior lenalidomide exposure was 57 (76.0%). The numbers of progressive disease (PD) and non-PD before ERd were 23 (30.7%) and 52 (69.3%), respectively. The frequency of PD before ERd was significantly lower in the monthly ERd group than in the conventional ERd group. In 26.9 months of median follow-up period, the 2-year progression-free survival (PFS) rate in the monthly ERd group was significantly longer than that in the conventional ERd group (95.0% and 62.0%, hazard ratio 0.082, p = 0.002). However, no significant difference in PFS between these two ERd groups was found using multivariate analysis. The complete response rates were similar between the monthly and conventional ERd groups (55.0% and 32.7%, p = 0.109). There was no significant difference in the incidence of adverse events between the monthly and conventional ERd groups (35.0% and 54.5%, p = 0.192). There was no significant difference in the kinetics of the mean absolute lymphocyte count, CD4, CD8, CD16, CD56, and CD57 positive lymphocyte counts, and CD4 to CD8 ratio between the monthly and conventional ERd groups. DISCUSSION: The efficacy and tolerability of monthly ERd were similar to those of conventional ERd. Thus, monthly ERd might be a reasonable option, considering the quality of life of patients and convenience.

Elotuzumab Plus Pomalidomide and Dexamethasone for Relapsed/Refractory Multiple Myeloma: Final Overall Survival Analysis From the Randomized Phase II ELOQUENT-3 Trial.

PURPOSE: In the phase II ELOQUENT-3 trial (ClinicalTrials.gov identifier: NCT02654132), elotuzumab combined with pomalidomide/dexamethasone (EPd) significantly improved progression-free survival (PFS) versus pomalidomide/dexamethasone (Pd) in patients with relapsed/refractory multiple myeloma (RRMM) previously treated with lenalidomide and a proteasome inhibitor (PI). Here, we present the final overall survival (OS) results. METHODS: Patients with RRMM who had received ≥ 2 prior lines of therapy, with disease refractory to last therapy and either refractory or relapsed and refractory to lenalidomide and a PI were randomly assigned (1:1) to receive EPd or Pd. The primary end point was PFS per investigator assessment. ORR and OS were secondary end points planned to be tested hierarchically. RESULTS: A total of 117 patients were randomly assigned to EPd (n = 60) and Pd (n = 57). Among treated patients (EPd 60, Pd 55), there were 37 (61.7%) deaths in the EPd group and 41 (74.5%) in the Pd group, most commonly because of disease progression (EPd 41.7%, Pd 49.1%). Median (95% CI) OS was significantly improved with EPd (29.8 [22.9 to 45.7] months) versus Pd (17.4 [13.8 to 27.7] months), with a hazard ratio of 0.59 (95% CI, 0.37 to 0.93; P = .0217). OS benefit with EPd was observed in most patient subgroups. The safety profile of EPd was consistent with prior reports with no new safety signals detected. CONCLUSION: EPd demonstrated a statistically significant improvement in OS versus Pd in patients with RRMM previously treated with lenalidomide and a PI who had disease refractory to last therapy. In this setting, ELOQUENT-3 is the first randomized study of a triplet regimen incorporating a monoclonal antibody and Pd to improve both PFS and OS significantly.

Alternating bortezomib-dexamethasone and lenalidomide-dexamethasone in patients with newly diagnosed multiple myeloma aged over 75 years.

More than 40% of Japanese patients with multiple myeloma (MM) are over 75 years of age at diagnosis. Regardless of the treatment benefits, complications and relapses obstruct long-term survival. We conducted a phase II, open-label, single-arm, multicenter clinical trial to assess the efficacy and safety of alternating bortezomib-dexamethasone (Bd) and lenalidomide-dexamethasone (Ld) (Bd/Ld) treatment in MM patients aged over 75 years (MARBLE trial). Patients received Bd therapy from days 1 to 35 and Ld therapy from days 36 to 63. For Bd therapy, patients were administered bortezomib 1.3 mg/m2 and oral dexamethasone 20 mg on days 1, 8, 15, and 22. For Ld therapy, they were administered lenalidomide 15 mg from days 36 to 56 and dexamethasone 10 mg on days 36, 43, 50, and 57. They underwent six treatment cycles in total, each consisting of a 63-day regimen. In total, 10 patients were enrolled, with a median age of 81 years. Efficacy was not evaluated because the patients were fewer than planned. The overall response rate was 80.0% and complete response rate 40.0%. Seventy percent of patients completed the study treatment. Progression-free survival and overall survival at 2 years were 40.0% and 80.0%, respectively. Adverse events of grade 3 or higher, including anemia, decreased lymphocyte count, neutropenia, and hypokalemia, were observed in eight patients. Alternating chemotherapy with Bd/Ld might be feasible, but its efficacy should be verified further.

Real-world treatment patterns and clinical outcomes in patients with AML in Japan who were ineligible for first-line intensive chemotherapy.

Acute myeloid leukemia (AML) predominantly affects elderly adults, and its prognosis worsens with age. Treatment options for patients in Japan ineligible for intensive chemotherapy include cytarabine/aclarubicin ± granulocyte colony-stimulating factor (CA ± G), azacitidine (AZA), low-dose cytarabine (LDAC), targeted therapy, and best supportive care (BSC). The country's aging population and the evolving treatment landscape are contributing to a need to understand treatment pathways and associated outcomes. This retrospective chart review evaluated outcomes in patients across Japan with primary/secondary AML who were ineligible for intensive chemotherapy and began first-line treatment or BSC between 01/01/2015 and 12/31/2018. The primary endpoint was overall survival (OS); secondary endpoints included progression-free survival (PFS) and healthcare resource utilization (HRU). Of 199 patients (58% > 75 years), 121 received systemic therapy (38 CA ± G, 37 AZA, 7 LDAC, 39 other) and 78 received BSC. Median OS was 5.4, 9.2, 2.2, 3.8, and 2.2 months for CA ± G, AZA, LDAC, other systemic therapy, and BSC, respectively; median PFS was 3.4, 7.7, 1.6, 2.3, and 2.1 months, respectively. HRU rates were uniformly high, with > 80% patients hospitalized in each cohort. The poor clinical outcomes and high HRU among Japanese AML patients who are ineligible for intensive chemotherapy highlight an unmet need for novel therapies.

Efficacy and safety of Wilms' tumor 1 helper peptide OCV-501 in elderly patients with acute myeloid leukemia: a multicenter, randomized, double-blind, placebo-controlled phase 2 trial.

PURPOSE: Complete remission (CR) of acute myeloid leukemia (AML) in elderly patients has a short duration, and there is no suitable post-remission therapy. We explored the role of the Wilms' tumor 1 helper peptide OCV-501 to prevent recurrence after remission. METHODS: This placebo-controlled phase 2 study was designed to evaluate accurately the efficacy and immunogenicity of OCV-501 in elderly AML patients. Elderly AML patients who achieved first CR were randomly allocated to receive either OCV-501 (N = 69) or placebo (N = 65) once a week for eight weeks and then every two weeks until week 104. The primary endpoint was disease-free survival (DFS). RESULTS: Nineteen (27.5%) patients in the OCV-501 group and 23 (35.4%) patients in the placebo group completed the study without relapse. The median DFS in the OCV-501 and placebo groups was 12.1 and 8.4 months, respectively (p = 0.7671, hazard ratio [95% confidence interval]: 0.933 [0.590, 1.477]). The major drug adverse reactions were injection-site reactions. Although treatment with OCV-501 did not prolong DFS for elderly AML patients, post hoc analysis found that immune responders to OCV-501 whose specific IgG was > 10,000 ng/mL (N = 16) and whose WT1-specific interferon-γ response was > 10 pg/mL (N = 26) had significantly longer overall survival compared with placebo. CONCLUSIONS: The placebo-controlled design of this study and quantitative immunological monitoring provides new insight into the relationship between peptide-induced immune responses and survival, suggesting future perspectives for cancer immunotherapy.

Clinical Features of Disseminated Intravascular Coagulation According to the French-American-British Classification in Patients With Acute Leukemia and Thrombomodulin Alfa Treatment-A Cohort Study Using a Postmarketing Surveillance Database.

The aims of this study were to analyze the clinical features of a large number of cases with disseminated intravascular coagulation (DIC) associated with acute leukemia and to assess the safety and efficacy of thrombomodulin alfa (TM-α) using the French-American-British (FAB) classification of hematological malignancies. We retrospectively examined 644 patients with acute leukemia in postmarketing surveillance for TM-α. M3, M2, M4, M1, and M5 subtypes of acute myeloid leukemia (AML) and L2 and L1 subtypes of acute lymphoblastic leukemia (ALL) have been found more frequently among patients with DIC. Bleeding symptoms at baseline were more frequent in M3 and M7 subtypes. Fibrinogen concentrations were lower, and plasmin-plasmin inhibitor complex values were higher in M3 and Philadelphia-positive (Ph+) ALL. Overall DIC resolution rate was 60.2%, higher in L1 and Ph+ ALL, lower in M1, and generally higher in ALL than in AML. Overall survival rate was generally high, at 79.8%, with higher rates in L3, Ph+ ALL, and M3. Regardless of FAB subgroup, TM-α showed improved bleeding symptoms and DIC scores in clinical practice for DIC patients with acute leukemia.

Once-weekly vs. twice-weekly carfilzomib dosing in a subgroup of Japanese relapsed and refractory multiple myeloma patients from a randomized phase 3 trial (A.R.R.O.W.) and comparison with ENDEAVOR.

A.R.R.O.W. evaluated the superiority of once-weekly carfilzomib plus dexamethasone (Kd) 20/70 mg/m2 vs. twice-weekly Kd 20/27 mg/m2 based on progression-free survival (PFS) in relapsed and/or refractory multiple myeloma patients. Forty Japanese patients (once-weekly arm, n = 26; twice-weekly arm, n = 14) were randomized in A.R.R.O.W. In the Japanese subgroup of A.R.R.O.W., median PFS was 14.8 months (95% confidence interval [CI], 7.5-not evaluable [NE]) and 9.7 months (95% CI, 3.8-NE) in the once- and twice-weekly arms, respectively. The overall response rate (ORR) was 73.1% (19/26; 95% CI, 52.2-88.4) and 57.1% (8/14; 95% CI, 28.9-82.3) in each arm. The adverse events (AEs) incidence was 100% in both arms. Grade ≥ 3 AE incidence was 80.8% (21/26) and 78.6% (11/14) in each arm. Two fatal treatment-related AEs (acute lung injury and acute respiratory distress syndrome) occurred in the once-weekly arm. In exploratory unadjusted analyses of A.R.R.O.W. (once-weekly Kd 20/70 mg/m2) vs. ENDEAVOR (twice-weekly Kd 20/56 mg/m2), median PFS was 14.8 months vs. NE due to not yet being reached, and ORR was 73.1% (19/26) vs. 42.9% (3/7). In the Japanese subgroup, once-weekly Kd tended to improve ORR vs. twice-weekly Kd. Results from A.R.R.O.W. tended to be consistent with results from ENDEAVOR.

Efficacy and Safety of Balloon Kyphoplasty for Pathological Vertebral Fractures in Patients with Hematological Malignancies in Our Institution.

Objective Patients with hematological malignancies, particularly those with multiple myeloma, often suffer from pathological vertebral compression fractures (VCFs). Consequent and significant spinal pain and paralysis impair the activities of daily living and quality of life and delay subsequent chemotherapy. Balloon kyphoplasty (BKP), which is less invasive than conventional therapies, is a type of percutaneous vertebroplasty in which cement is injected into the broken vertebrae to stabilize the spinal column. The present study assessed the effect of BKP on hematological tumors. Methods We retrospectively analyzed five myeloma patients and one lymphoma patient who underwent BKP for pathological VCFs in our institution. Results The median age was 74 years old. The spinal operation level ranged from T2 to L4. BKP was performed at the diagnosis in two cases, after first-line chemotherapy in one case, and after subsequent chemotherapy in three cases. After approximately 1 month, the patients' average Eastern Cooperative Oncology Group performance status score rapidly improved from 3.2 to 1.3. The numeric rating scale score decreased from 8.8 to 2.0, and the Karnofsky Performance Status score increased from 35 to 75. No severe complications were observed. All patients became able to walk unassisted and underwent early subsequent chemotherapy. Conclusion BKP can be a safe and effective treatment option for pathological VCFs in patients with hematological malignancies and allows for rapid induction with subsequent chemotherapy.

Daratumumab, lenalidomide, and dexamethasone in relapsed/refractory myeloma: a cytogenetic subgroup analysis of POLLUX.

High cytogenetic risk abnormalities confer poor outcomes in multiple myeloma patients. In POLLUX, daratumumab/lenalidomide/dexamethasone (D-Rd) demonstrated significant clinical benefit versus lenalidomide/dexamethasone (Rd) in relapsed/refractory multiple myeloma (RRMM) patients. We report an updated subgroup analysis of POLLUX based on cytogenetic risk. The cytogenetic risk was determined using fluorescence in situ hybridization/karyotyping; patients with high cytogenetic risk had t(4;14), t(14;16), or del17p abnormalities. Minimal residual disease (MRD; 10-5) was assessed via the clonoSEQ® assay V2.0. 569 patients were randomized (D-Rd, n = 286; Rd, n = 283); 35 (12%) patients per group had high cytogenetic risk. After a median follow-up of 44.3 months, D-Rd prolonged progression-free survival (PFS) versus Rd in standard cytogenetic risk (median: not estimable vs 18.6 months; hazard ratio [HR], 0.43; P < 0.0001) and high cytogenetic risk (median: 26.8 vs 8.3 months; HR, 0.34; P = 0.0035) patients. Responses with D-Rd were deep, including higher MRD negativity and sustained MRD-negativity rates versus Rd, regardless of cytogenetic risk. PFS on subsequent line of therapy was improved with D-Rd versus Rd in both cytogenetic risk subgroups. The safety profile of D-Rd by cytogenetic risk was consistent with the overall population. These findings demonstrate the improved efficacy of daratumumab plus standard of care versus standard of care in RRMM, regardless of cytogenetic risk.

Pembrolizumab plus lenalidomide and dexamethasone in treatment-naive multiple myeloma (KEYNOTE-185): subgroup analysis in Japanese patients.

The global, randomized, open-label KEYNOTE-185 study closed early after an interim analysis showed an unfavorable benefit-risk profile with pembrolizumab plus lenalidomide and low-dose dexamethasone (Rd) versus Rd alone in treatment-naive, transplant-ineligible multiple myeloma. This subgroup analysis reported outcomes in the Japanese population. Patients were randomly assigned (1:1) to pembrolizumab plus Rd or Rd alone, stratified by age and International Staging System. The primary end point was progression-free survival (PFS). Fifty-two Japanese patients were randomly assigned to pembrolizumab plus Rd (n = 27) or Rd (n = 25). The median follow-up was 7.2 months (range, 0.4-13.8). The median PFS was not reached (NR); 6-month PFS was 91.2% versus 86.2% with pembrolizumab plus Rd versus Rd [hazard ratio (HR), 0.31; 95% CI, 0.06-1.63]. The median overall survival (OS) was NR; 6-month OS was 96.2% versus 95.7% with pembrolizumab plus Rd versus Rd (HR, 0.33; 95% CI, 0.03-3.72). With pembrolizumab plus Rd versus Rd, grade 3-5 adverse events occurred in 70.4% versus 69.6% of patients; serious adverse events occurred in 40.7% versus 52.5%. Although in the Japanese subgroup of KEYNOTE-185 adding pembrolizumab to Rd did not show an unfavorable risk-benefit, the analysis is limited by short follow-up and small sample size, affecting generalizability of the results.

Severe Antithrombin Deficiency May be Associated With a High Risk of Pathological Progression of DIC With Suppressed Fibrinolysis.

The frequency of severe antithrombin deficiency (SAD) was examined in the hematopoietic disorder-, infectious-, and basic-types of the disseminated intravascular coagulation (DIC). A posthoc analysis of 3008 DIC patients (infectious-type, 1794; hematological disorder-type, 813; and basic-type, 401) from post-marketing surveillance data of thrombomodulin alfa was performed. The clinical features of patients and outcomes were compared between patients with and without SAD, using an antithrombin cutoff value of 50%. Patients with SAD accounted for 40.4% of infectious-type DIC, 8.0% of hematopoietic disorder-type DIC, and 26.7% of basic-type DIC. There was no significant difference in thrombin-antithrombin complex levels between patients with and without SAD. The decreased fibrinogen level and differences in clinical features were significantly greater but the increases in fibrinolytic markers were significantly lower in patients with SAD than in those without. The 28-day survival rate was significantly lower in patients with SAD than in those without. Severe antithrombin deficiency was observed in all types of DIC, including hematopoietic disorders. Both hypofibrinolysis and hypercoagulability in patients with SAD may cause multiple organ failure and poor outcomes.

[Hematologic malignancies and health economics].

Recently, there has been an increasing drive to consider the cost effectiveness of healthcare. Since clinical trials usually examine disease-free survival without considering overall survival, it is difficult to determine which treatment is cost effective. At present, the overall survival time is estimated using a Markov model, and the quality-adjusted life year (QALY) is calculated by taking into account the quality and quantity of life lived. In Japan, the cost required to obtain 1 QALY is expected to be around 5 million yen, and drug prices are being influenced by policy. Indubitably, this type of health economics also has limitations and is not equal for everyone. Thus, collaboration is necessary to discuss better and more efficient medical care. It is hoped that this review of two diseases of hematopoietic malignancy will enhance our understanding of health economics.

Silent NK/T cell reactions to dasatinib during sustained deep molecular response before cessation are associated with longer treatment-free remission.

This study presents the final report of the multicenter, prospective tyrosine kinase inhibitor discontinuation study, D-STOP, after a 3-year follow-up of 54 patients with chronic CML who discontinued dasatinib after a sustained deep molecular response (DMR) for ≥2 years with dasatinib treatment. Estimated treatment-free remission (TFR) rates at 12 and 36 months were 63.0% [95% confidence interval (CI): 48.7-74.3] and 59.3% (95% CI: 45.0-71.0), respectively. CD3- CD56+ NK, CD16+ CD56+ NK, and CD57+ CD56+ NK large granular lymphocyte (NK-LGL), CD8+ CD4- cytotoxic T cell, and CD57+ CD3+ T-LGL cell numbers were relatively elevated throughout the 24-month consolidation only in failed patients who molecularly relapsed within 12 months. In successful patients, these subsets elevated transiently after 12 months, but returned to basal levels after 24-month consolidation. Therefore, smaller changes in NK/T, particularly the NK subset throughout consolidation, reflected higher TFR rates. TFR rates of those patients exhibiting elevation in CD3- CD56+ NK >376 cells/µL, CD16+ CD56+ NK > 241 cells/µL, or CD57+ CD56+ NK-LGL >242 cells/µL during consolidation compared with others were 26.7% (8.3%-49.6%) vs 78.3% (55.4%-90.3%), HR 0.032 (0.0027-0.38; P = .0064), 31.2% (11.4%-53.6%) vs 85.0% (60.4%-94.9%), HR 0.039 (0.0031-0.48; P = .011), or 36.8% (16.5%-57.5%) vs 77.3% (53.7%-89.8%), HR 0.21 (0.065-0.69; P = .010), respectively. Therefore, silent responses of T/NK subsets to dasatinib throughout consolidation were significant for longer TFR. Elevated NK/T, particularly NK lymphocytes responsive to dasatinib, may be immunologically insufficient to maintain TFR. Their decline, subsequently replaced by altered lymphocyte population with less response to dasatinib during sustained DMR, might be immunologically significant. (D-STOP, NCT01627132).

Pomalidomide-bortezomib-dexamethasone in relapsed or refractory multiple myeloma: Japanese subset analysis of OPTIMISMM.

In the phase 3 OPTIMISMM trial, pomalidomide, bortezomib and dexamethasone (PVd) significantly improved the progression-free survival (PFS) and the overall response rate (ORR) vs bortezomib and dexamethasone (Vd) in patients with relapsed or refractory multiple myeloma. All patients were previously treated with lenalidomide (70% refractory to lenalidomide) and had received one to three prior regimens. Here we report the first efficacy and safety analysis of PVd vs Vd in Japanese patients with relapsed or refractory multiple myeloma. Seventeen patients enrolled in the OPTIMISMM trial in Japan. With a median follow-up of 14.8 months, the median PFS was 17.6 months with PVd (n = 12) vs 4.4 months with Vd (n = 5), and the ORR was 100% vs 60.0%, respectively. The safety profile was as expected for PVd. Toxicities were managed with dose reductions and interruptions, and no patients discontinued PVd due to treatment-emergent adverse events. These results are consistent with those in the overall OPTIMISMM patient population and confirm the clinical benefit of PVd in Japanese patients.

Continuous lenalidomide treatment after bortezomib-melphalan-prednisolone therapy for newly diagnosed multiple myeloma.

These are the results of phase II study of bortezomib-melphalan-prednisolone (VMP) induction therapy followed by lenalidomide-dexamethasone (Rd) consolidation and lenalidomide maintenance in transplant-ineligible patients with newly diagnosed multiple myeloma (NDMM). The primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), overall response rates (ORRs), and safety. Eighty-three eligible patients were enrolled between October 2012 and August 2014. The median PFS was 28.0 months (95% CI 19.6-36.7) and the median OS was 55.3 months (95% CI 51.6-NA). Among the patients who received lenalidomide maintenance therapy, median PFS was significantly improved in patients who had achieved a very good partial response (VGPR) or better (41.8 vs 20.7 months, p = 0.0070). As the best response, the rates of partial response or better were 85.5% comprising stringent complete response (sCR, 21.7%), complete response (CR, 10.8%), VGPR (18.1%), and partial response (PR, 34.9%). The most frequently observed grade 3 or higher adverse events during the VMP therapy were anemia (28.9%), neutropenia (15.6%), thrombocytopenia (6.0%), and peripheral neuropathy (2.4%). The most frequently observed grade 3 or higher adverse events during the Rd therapy were anemia (3.5%), neutropenia (1.8%), and skin rush (5.3%). The most frequently observed grade 3 or higher adverse events during lenalidomide maintenance therapy were anemia (7.4%) and neutropenia (24.1%). Thus, VMP induction therapy followed by Rd consolidation and lenalidomide maintenance is considered a well-tolerated and effective regimen in transplant-ineligible NDMM. This trial is registered with UMIN-CTR with the identification number UMIN000009042.