Carfilzomib monotherapy in Japanese patients with relapsed or refractory multiple myeloma: A phase 1/2 study

This multicenter, open-label phase 1/2 study evaluated single-agent carfilzomib in 50 heavily pretreated Japanese patients with relapsed/refractory multiple myeloma (median of five prior treatments). In phase 1, patients were dosed at three levels: 15, 20, or 20/27 mg/m² . Maximum tolerated dosage was not reached at the tolerability evaluation. Patients in phase 2 were treated with 20/27 mg/m² carfilzomib. Median duration of exposure to carfilzomib in the 20/27 mg/m² group at this final analysis was 4.7 months (range: 0.3-39.4). Overall response rate in the 20/27 mg/m² group, primary endpoint of the study, was 22.5% (n = 9) (95% confidence interval, 12.3-37.5) with 2.5% (n = 1) stringent complete response. Median progression-free survival and overall survival in the 20/27 mg/m² group were 5.1 months (95% CI, 2.8-13.6) and 22.9 months (95% CI, 14.1-not estimable), respectively. Frequently occurring grade ≥3 adverse events in the 20/27 mg/m² group included lymphopenia (72.5%), neutropenia (40.0%), and leukopenia (32.5%). Giving long-term carfilzomib monotherapy led to long-term overall survival for heavily pretreated multiple myeloma patients with a favorable safety profile. Carfilzomib monotherapy can be a good option for heavily pretreated multiple myeloma patients.

Combined rituximab, bendamustine, and dexamethasone chemotherapy for relapsed or refractory indolent B-cell non-Hodgkin lymphoma and mantle cell lymphoma: a multicenter phase II study

This multicenter phase II study (UMIN000008145) aims to investigate the efficacy and safety of six cycles of combination therapy (RBD) comprising rituximab, bendamustine, and dexamethasone (DEX) for relapsed or refractory (RR) indolent B-cell non-Hodgkin lymphoma (B-NHL) and mantle cell lymphoma (MCL). Although the initial study protocol comprised 20 mg/body DEX on days 1 and 2, and 10 mg/body on days 3-5 [high-dose (HD-) DEX group], the dose of DEX was later decreased to 8 mg/body on days 1 and 2 [low-dose (LD-) DEX group] due to frequent cytomegalovirus (CMV) antigenemia and recurrent retinitis. We enrolled 33 patients, and LD-DEX and HD-DEX were administered in 15 and 18 patients, respectively. The overall response and the 3-year progression-free survival rates were 88% and 75.5%, respectively. The leading adverse event was myelosuppression. Incidence of grade 3-4 leukocytopenia, neutropenia, and lymphocytopenia was 55%, 67%, and 91%, respectively. The most frequent nonhematological adverse events were CMV antigenemia and rash (33% and 30%, respectively). Incidence of CMV antigenemia over 10/100,000 white blood cells was significantly lower with LD-DEX than that with HD-DEX (P = 0.0127). In conclusion, RBD showed significant effectiveness for RR indolent B-NHL and MCL.

A novel method of amplified fluorescent in situ hybridization for detection of chromosomal microdeletions in B cell lymphoma

Chromosomal microdeletions frequently cause loss of prognostically relevant tumor suppressor genes in hematologic malignancies; however, detection of minute deletions by conventional methods for chromosomal analysis, such as G-banding and fluorescence in situ hybridization (FISH), is difficult due to their low resolution. Here, we describe a new diagnostic modality that enables detection of chromosomal microdeletions, using CDKN2A gene deletion in B cell lymphomas (BCLs) as an example. In this method, which we refer to as amplified-FISH (AM-FISH), a 31-kb fluorescein isothiocyanate (FITC)-conjugated DNA probe encoding only CDKN2A was first hybridized with the chromosome, and then labeled with Alexa Fluor 488-conjugated anti-FITC secondary antibody to increase sensitivity. CDKN2A signals were equally identifiable by AM-FISH and conventional FISH in normal mononuclear blood cells. In contrast, when two BCL cell lines lacking CDKN2A were analyzed, CDKN2A signals were not detected by AM-FISH, whereas conventional FISH yielded false signals. Furthermore, AM-FISH detected CDKN2A deletions in two BCL patients with 9p21 microdeletions, which were not detected by conventional FISH. These results suggest that AM-FISH is a highly sensitive, specific, and simple method for diagnosis of chromosomal microdeletions.

Immunosuppressive therapy with rabbit antithymocyte globulin therapy for acquired aplastic anemia: a multi-institutional retrospective study in Japanese adult patients

We retrospectively analyzed efficacy and safety of therapy with rabbit antithymocyte globulin (rATG) in combination with cyclosporine A (CsA) in 30 Japanese adult patients with acquired aplastic anemia (AA) in the Kyoto Clinical Hematology Study Group. The median observation period was 31 months and the median age of the patients was 54 years. The objective response rates (ORRs) to rATG plus CsA increased over time until 18 months after the start of treatment; the rate of achievement of better than partial response at 18 months was 66.7%. The 2-year overall survival (OS) rate was 79% in all patients. In eight patients aged ≥ 75 years old, the ORR was 62.5% and the 2-year OS rate of 50% was not significantly inferior to that in patients aged ≤ 74 years old. The overall mortality rate was 16.7% in our cohort, while the mortality rate in patients aged ≥ 75 years old was 37.5%, which was higher than that in patients aged ≤ 74 years old (9.1%), although the difference was not statistically significant. Collectively, rATG combined with CsA is an effective and feasible treatment for AA, while patients should be appropriately selected.

Outcomes after R-CHOP in patients with newly diagnosed advanced follicular lymphoma: a 10-year follow-up analysis of the JCOG0203 trial

BACKGROUND

Standard treatment for untreated advanced-stage follicular lymphoma is rituximab plus chemotherapy. The incidence of histological transformation of follicular lymphoma has been reported only in heterogeneously treated populations and rarely with long-term follow-up. Additionally, the incidence of secondary malignancies after treatment, without high-dose therapy for follicular lymphoma, is largely unknown. The aim of our study was to assess progression-free survival, overall survival, incidence of secondary malignancies, and incidence of histological transformation in a 10-year follow-up analysis of the JCOG0203 trial.

METHODS

In the phase 2-3 randomised JCOG0203 trial, previously untreated patients with stage III or IV indolent B-cell lymphoma, including grades 1-3 follicular lymphoma, from 44 hospital centres in Japan, were randomly assigned (1:1) by use of a minimisation method to receive six cycles of R-CHOP (rituximab [375 mg/m²], given on day 1, plus cyclophosphamide [750 mg/m²], doxorubicin [50 mg/m²], vincristine [1·4 mg/m², capped at 2·0 mg] given intravenously on day 3, and oral prednisone [100 mg once daily on days 3-7]) every 3 weeks (R-CHOP-21) or every 2 weeks (enabled by mandatory granulocyte-colony stimulating factor administration once daily for 6 days, starting on day 8; R-CHOP-14) without rituximab maintenance. Age, bulky disease (nodal or extranodal mass ≥10 cm in diameter on CT), and institution were used as adjustment factors. Investigators enrolled participants, and assignment to trial groups was done with a computer-assisted randomisation allocation sequence that took place centrally at the Japan Clinical Oncology Group Data Center, without the intervention of investigators. Interventions were not masked for patients or investigators. Data were collected 10 years after enrolment of the last patient. The primary endpoint of the phase 3 part of the study was progression-free survival, and the primary endpoint of the phase 2 part of the study was the proportion of patients who achieved a complete response. Accrual was 4·5 years, and follow-up was 3 years after registration was closed. Data were updated on the cutoff date of Feb 28, 2017. Intention-to-treat analyses (ie, progression-free survival, overall survival, and incidence of secondary malignancies) were predefined, to be done at 10 years after the last patient was enrolled. An additional analysis of the incidence of histological transformation was defined 15 years after the protocol, on May 8, 2017, in a supplementary analysis plan, and assessed at 10 years after the last patient was enrolled. Follow-up is ongoing. This trial is registered with ClinicalTrials.gov, number NCT00147121.

FINDINGS

Between Sept 1, 2002, and Feb 28, 2007, 300 patients were enrolled, and 149 (50%) were assigned to the R-CHOP-21 group and 151 (50%) were assigned to the R-CHOP-14 group. After eligibility was assessed, one patient was excluded from the R-CHOP-21 group. 10-year progression-free survival was not different between groups (R-CHOP-21 33%, 95% CI 25-41; R-CHOP-14 39%, 31-47; hazard ratio 0·89, 95% CI 0·67-1·17). In 248 patients with grade 1-3a follicular lymphoma, progression-free survival was 39% (33-45) at 8 years and 36% (30-42) at 10 years. The cumulative incidence of histological transformation was 3·2% (95% CI 1·5-6·0) at 5 years, 8·5% (5·4-12·4) at 8 years, and 9·3% (6·1-13·4) at 10 years after enrolment. At 10 years, the cumulative incidence of secondary malignancies was 8·1% (5·1-12·0) and the cumulative incidence of haematological secondary malignancies was 2·9% (1·3-5·5).

INTERPRETATION

R-CHOP is a viable option for first-line treatment in patients with newly diagnosed advanced follicular lymphoma. Clinicians choosing a first-line treatment for patients with follicular lymphoma should be cautious of secondary malignancies caused by immunochemotherapy and severe complications of infectious diseases in the long-term follow-up-both of which could lead to death.

FUNDING

National Cancer Center and Ministry of Health, Labour and Welfare of Japan.

Establishment and characterization of a novel vincristine-resistant diffuse large B-cell lymphoma cell line containing the 8q24 homogeneously staining region

Chromosome band 8q24 is the most frequently amplified locus in various types of cancers. MYC has been identified as the primary oncogene at the 8q24 locus, whereas a long noncoding gene, PVT1, which lies adjacent to MYC, has recently emerged as another potential oncogenic regulator at this position. In this study, we established and characterized a novel cell line, AMU‐ML2, from a patient with diffuse large B‐cell lymphoma (DLBCL), displaying homogeneously staining regions at the 8q24 locus. Fluorescence in situ hybridization clearly detected an elevation in MYC copy numbers corresponding to the homogenously staining region. In addition, a comparative genomic hybridization analysis using high‐resolution arrays revealed that the 8q24 amplicon size was 1.4 Mb, containing the entire MYC and PVT1 regions. We also demonstrated a loss of heterozygosity for TP53 at 17p13 in conjunction with a TP53 frameshift mutation. Notably, AMU‐ML2 cells exhibited resistance to vincristine, and cell proliferation was markedly inhibited by MYC‐shRNA‐mediated knockdown. Furthermore, genes involved in cyclin D, mTOR, and Ras signaling were downregulated following MYC knockdown, suggesting that MYC expression was closely associated with tumor cell growth. In conclusion, AMU‐ML2 cells are uniquely characterized by homogenously staining regions at the 8q24 locus, thus providing useful insights into the pathogenesis of DLBCL with 8q24 abnormalities.

Establishment and Characteristics of a Novel Mantle Cell Lymphoma-derived Cell Line and a Bendamustine-resistant Subline

BACKGROUND/AIM

Bendamustine hydrochloride (BH) is a key therapeutic agent for mantle cell lymphoma (MCL), while the mechanism underlying BH-resistance has not been verified.

MATERIALS AND METHODS

We compared molecular/biological characteristics of a newly-generated MCL-derived cell line KPUM-YY1 and its BH-resistant subline KPUM-YY1R.

RESULTS

The growth-inhibitory IC₅₀ for BH was 20 μM in KPUM-YY1 cells, while cell proliferation was not inhibited by up to 60 μM BH in KPUM-YY1R cells. Compared to KPUM-YY1 cells, gene expression profiling in KPUM-YY1R cells revealed up-regulation of 312 genes, including ABCB1 encoding P-glycoprotein (P-gp), and microsomal glutathione S-transferase 1 (MGST1). Addition of either a P-gp inhibitor or a GST inhibitor, at least partly, restored sensitivity to BH in KPUM-YY1R cells. In addition, KPUM-YY1R cells showed cross-resistance against various anti-MCL chemotherapeutics.

CONCLUSION

BH resistance is mediated by overlapping mechanisms with overexpression of ABCB1 and MGST1, and is potentially accompanied by multidrug resistance in MCL.

Weekly carfilzomib and dexamethasone in Japanese patients with relapsed or refractory multiple myeloma: A phase 1 and PK/PD trial

This open‐label multicenter phase 1 study evaluated the safety, tolerability, efficacy, pharmacokinetics and pharmacodynamics of weekly carfilzomib and dexamethasone (Cd) in Japanese patients with relapsed or refractory multiple myeloma (RRMM). Carfilzomib was administered by 30‐minute intravenous infusion on Days 1, 8 and 15 in a 28‐day cycle starting at 20 mg/m² on Day 1/Cycle 1 and 70 mg/m² thereafter until progressive disease or unacceptable toxicity. Dexamethasone 40 mg was administered on Days 1, 8, 15 and 22 in Cycles 1‐9 and on Days 1, 8 and 15 thereafter. Six patients were enrolled between March 2015 and June 2015. Patients had received a median of 4.5 (range, 4‐8) prior regimens; all patients had previous therapies with bortezomib and immunomodulatory drugs. Of the 6 patients, 1 had a dose‐limiting toxicity (DLT), and tolerability was confirmed. The DLT was grade 3 thrombotic microangiopathy, which was considered serious and occurred on Day 11/Cycle 1. All 6 patients (100%) experienced at least 1 grade ≥3 adverse event (AE). Two patients (33.3%) experienced AE (also considered adverse drug reactions) leading to study discontinuation: thrombotic microangiopathy (Day 11/Cycle 1) and thrombotic thrombocytopenic purpura (Day 6/Cycle 2). The overall response rate was 83.3% (95% confidence interval, 43.6‐97.0). The weekly Cd regimen at a carfilzomib dose of 20/70 mg/m² was well‐tolerated among Japanese patients with RRMM. Our results could be the basis for the further development of carfilzomib treatment considering safety profiles including microangiopathy‐related events and efficacy.

Correction to: Multicenter phase 1/2 study of forodesine in patients with relapsed peripheral T cell lymphoma

The original version of this article contained a mistake in Fig. 4. The horizontal axis should be 36 instead of 60.

R-High-CHOP/CHASER/LEED with autologous stem cell transplantation in newly diagnosed mantle cell lymphoma: JCOG0406 STUDY

Although induction immunochemotherapy including high‐dose cytarabine and rituximab followed by high‐dose chemotherapy (HDC) with autologous stem cell transplantation (ASCT) is recommended for younger patients (≤65 years old) with untreated mantle cell lymphoma (MCL), no standard induction and HDC regimen has been established. We conducted a phase II study of induction immunochemotherapy of R‐High‐CHOP/CHASER followed by HDC of LEED with ASCT in younger patients with untreated advanced MCL. Eligibility criteria included untreated MCL, stage II bulky to IV, and age 20‐65 years. Patients received 1 cycle of R‐High‐CHOP followed by 3 cycles of CHASER every 3 weeks. Peripheral blood stem cells (PBSC) were harvested during CHASER. LEED with ASCT was delivered to patients who responded to R‐High‐CHOP/CHASER. Primary endpoint was 2‐year progression‐free survival (PFS). From June 2008 to June 2012, 45 patients (median age 59 years; range 38‐65 years) were enrolled. PBSC were successfully harvested from 36 of 43 patients. Thirty‐five patients completed ASCT. Two‐year PFS was 77% (80% CI 68‐84), which met the primary endpoint. Five‐year PFS and overall survival were 52% (95% CI 34‐68%) and 71% (95% CI 51‐84%), respectively. Overall response and complete response rates after induction immunochemotherapy were 96% and 82%, respectively. The most common grade 4 toxicities were hematological. In younger patients with untreated MCL, R‐High‐CHOP/CHASER/LEED with ASCT showed high efficacy and acceptable toxicity, and it can now be considered a standard treatment option.

Dual targeting of bromodomain-containing 4 by AZD5153 and BCL2 by AZD4320 against B-cell lymphomas concomitantly overexpressing c-MYC and BCL2

Despite the recent therapeutic progress, the prognoses of diffuse large B-cell lymphomas (DLBCLs) that concomitantly overexpress c-MYC and BCL2, i.e., double hit lymphoma (DHL) and double expressing lymphoma (DEL), remain poor. This study examined triple targeting of c-MYC, BCL2 and the B-cell receptor (BCR) signaling pathway for DHL and DEL. We first used AZD5153, a novel bivalent inhibitor for bromodomain-containing 4 (BRD4), in DHL- and DEL-derived cell lines, because BRD4 regulates disease type-oriented key molecules for oncogenesis. AZD5153 was more effective than conventional monovalent BRD4 inhibitors, JQ1 and I-BET151, in inhibiting cell proliferation of a DHL-derived cell line and two DEL-derived cell lines, with at least 10-fold lower half growth inhibitory concentrations. AZD5153 caused G1/S cell cycle blockade, while the apoptosis-inducing effect was relatively modest. At the molecular level, AZD5153 was potent in downregulating various molecules for oncogenesis, such as c-MYC, AKT2 and MAP3K; those involved in the BCR signaling pathway, such as CD19, BLNK and CD79B; and those associated with B-cell development, such as IKZF1, IKZF3, PAX5, POU2AF1 and EBF1. In contrast, AZD5153 did not decrease anti-apoptotic BCL2 proteins, and did not activate pro-apoptotic BH3-only proteins, except BAD. To augment cell death induction, we added a novel BH3-mimicking BCL2 inhibitor AZD4320 to AZD5153, and found that these two agents had a mostly synergistic antitumor effect by increasing cells undergoing apoptosis in all three cell lines. These results provide a rationale for dual targeting of BRD4 and BCL2 using AZD5153 and AZD4320 as a therapeutic strategy against DHL and DEL.

A Phase I/II Study for Dose-finding, and to Investigate the Safety, Pharmacokinetics and Preliminary Efficacy of NK012, an SN-38-Incorporating Macromolecular Polymeric Micelle, in Patients with Multiple Myeloma

Objective Multiple myeloma (MM) is the second most common hematological cancer. An attempt to treat MM using a topoisomerase I inhibitor was made based on our previous non-clinical studies suggesting the usefulness of an SN-38 derivative. Our aim was to conduct a phase I/II study of NK012, a micelle-forming SN-38 conjugate, in patients with relapsed/refractory multiple myeloma (RRMM). Methods NK012 was administered at doses of 12-24 mg/m² and the safety, pharmacokinetics and preliminary efficacy were evaluated. Results Neutropenia was the most common grade 3 or 4 adverse drug reaction. Grade 4 neutropenia accounted for the majority of dose-limiting toxicities and only appeared at a dose of 24 mg/m². The maximum concentrations and the area under the concentration-time curves from time zero to infinity for both NK012 and its active metabolite SN-38 increased in a dose-dependent manner. The best overall response was stable disease, which was achieved in 12 out of 16 patients. Conclusion The recommended dose of NK012 monotherapy for RRMM patients was concluded to be 20 mg/m². However, this phase I/II study was terminated at the end of the phase I stage because no patients showed an objective response. Additional clinical studies of combination therapy with NK012 and other agents are warranted.

[Lenalidomide and low-dose dexamethasone therapy for Japanese patients with newly diagnosed multiple myeloma: updated results of the MM-025 study]

In a Japanese phase II study (MM-025), the efficacy and safety of lenalidomide plus low-dose dexamethasone (Rd) were confirmed at a median follow-up of 14.2 months in patients with newly diagnosed multiple myeloma who were ineligible for hematopoietic stem cell transplantation. In the present report, we analyzed the follow-up data from the abovementioned study. Treatment was stopped for all 26 patients after a median follow-up of 31.3 months, and the median treatment duration was approximately 25 months. The overall response rate was 87.5%, and the complete response rate was 20.8%. The median duration of response and progression-free survival were 30.7 and 31.6 months, respectively. The median overall survival has not yet been reached. At least one grade 3/4 adverse event was experienced by 23 patients (88.5%), and 18 patients (69.2%) experienced serious adverse events. There were no treatment-related deaths. Therefore, the efficacy and safety of Rd were confirmed in transplant-ineligible Japanese patients with newly diagnosed multiple myeloma at the present follow-up period.

Chromosomal abnormality variation detected by G-banding is associated with prognosis of diffuse large B-cell lymphoma treated by R-CHOP-based therapy

Diffuse large B-cell lymphoma (DLBCL), which is the most prevalent disease subtype of non-Hodgkin lymphoma, is highly heterogeneous in terms of cytogenetic and molecular features. This study retrospectively investigated the clinical impact of G-banding-defined chromosomal abnormality on treatment outcomes of DLBCL in the era of rituximab-containing immunochemotherapy. Of 181 patients who were diagnosed with DLBCL and treated with R-CHOP or an R-CHOP-like regimen between January 2006 and April 2014, metaphase spreads were evaluable for G-banding in 120. In these 120 patients, 40 were found to harbor a single chromosomal aberration type; 63 showed chromosomal abnormality variations (CAVs), which are defined by the presence of different types of chromosomal abnormalities in G-banding, including 19 with two CAVs and 44 with ≥3 CAVs; and 17 had normal karyotypes. No specific chromosomal break point or numerical abnormality was associated with overall survival (OS) or progression-free survival (PFS), but the presence of ≥3 CAVs was significantly associated with inferior OS rates (hazard ratio (HR): 2.222, 95% confidence interval (CI): 1.056-4.677, P = 0.031) and tended to be associated with shorter PFS (HR: 1.796, 95% CI: 0.965-3.344, P = 0.061). In addition, ≥3 CAVs more frequently accumulated in high-risk patients, as defined by several conventional prognostic indices, such as the revised International Prognostic Index. In conclusion, our results suggest that the emergence of more CAVs, especially ≥3, based on chromosomal instability underlies the development of high-risk disease features and a poor prognosis in DLBCL.

An adult-onset case of chronic active Epstein-Barr virus infection with fulminant clinical course

A 56-year-old Japanese male with chronic active Epstein-Barr virus (EBV) infection (CAEBV) who developed systemic gamma-delta T-cell lymphoproliferative disease (LPD) is reported. Although immune cooling therapy was effective, he died of sudden and severe hypoxia and anemia soon after the initiation of cytotoxic chemotherapy that had been previously recommended. There might remain a difficulty to control fulminant adult-onset CAEBV. Additionally, we describe three types of lymphoid cells that were observed in his peripheral blood: morphologically normal lymphocytes, large blastic cells and mature ones with rough granules. Morphological observation appeared to be useful to estimate clinical manifestations. Since CAEBV is extremely rare disease in adult population, it is important to accumulate clinical data to more understand the pathogenesis or to establish treatment strategy.