Secondary central nervous system involvement in patients with diffuse large B-cell lymphoma treated with rituximab combined CHOP therapy - a supplementary analysis of JCOG0601.

Secondary central nervous system involvement (sCNSi) in diffuse large B-cell lymphoma (DLBCL) is fatal. However, its features in patients with sCNSi who are categorized as lower risk by international prognostic index (IPI) or CNS-IPI are not yet fully understood. In the present analysis, we evaluated DLBCL patients who developed sCNSi at their first progression and who participated in JCOG0601, most of whom were lower risk by IPI. Of 409 patients, 21 (5.1%) developed sCNSi during a median follow-up of 4.9 years. Five-year cumulative incidence of sCNSi were 5.1%; and 4.0%, 5.3%, and 11.5% at low, intermediate, and high risk of CNS-IPI, respectively. The most common locations of extranodal lesions at the time of registration in patients with sCNSi were the stomach (n = 4), paranasal cavity (n = 3), and bone marrow (n = 2). In univariable analysis, paranasal cavity lesion was a high-risk factor for sCNSi (subdistribution hazard ratio, 4.34 [95% confidence interval 1.28-14.73]). Median overall survival after sCNSi was 1.3 years, with a 2-year overall survival rate of 39.3%. The incidence of sCNSi in DLBCL patients at lower risk of CNS-IPI was low, as previously reported, but paranasal cavity lesion might indicate high risk for organ involvement. CLINICAL TRIAL REGISTRATION: JCOG0601 was registered in the UMIN Clinical Trials Registry (UMIN000000929, date of registration; December 04, 2007) and the Japan Registry of Clinical Trials (jRCTs031180139, date of registration; February 20, 2019).

Long-term follow-up after R-High CHOP/CHASER/LEED with Auto-PBSCT in untreated mantle cell lymphoma-Final analysis of JCOG0406.

Progression-free survival after R-High CHOP/CHASER/LEED with auto-PBSCT in untreated mantle cell lymphoma in JCOG0406 study. A continuous pattern of relapse was observed.

Long-term safety profile of tirabrutinib: final results of a Japanese Phase I study in patients with relapsed or refractory B-cell malignancies.

Tirabrutinib is a Bruton's tyrosine kinase inhibitor for treating B-cell malignancies. We report the final results of a Phase I study of tirabrutinib in 17 Japanese patients with B-cell malignancies. Patients were administered tirabrutinib at a dose of 160 mg, 320 mg, or 480 mg once daily, or 300 mg twice daily (N = 3, 3, 4, and 7, respectively). Three patients continued tirabrutinib until study completion (November 30, 2020). Adverse events (AEs) occurred in all 17 patients, with Grade 3-4 AEs in 8 (47.1%), serious AEs in 7 (41.2%), drug-related AEs in 16 (94.1%), and Grade 3-4 drug-related AEs in 6 (35.3%). Drug-related AEs reported in 3 or more patients were rash, vomiting, neutropenia, arthralgia, and malaise. One additional serious AE (benign neoplasm of the lung, unrelated to tirabrutinib) occurred after the previous data cutoff (January 4, 2018). Tirabrutinib administration and response assessment were continued for over 4 years in 4 patients. The overall response rate was 76.5% (13/17 patients). The median (range) time to response and duration of response were 0.9 (0.9-5.9) months and 2.59 (0.08-5.45) years, respectively. These findings demonstrate the long-term safety and efficacy of tirabrutinib in Japanese patients with B-cell malignancies.Clinical trial registration: JapicCTI-142682 ( http://www.clinicaltrials.jp/ ).

A multicenter, phase II study of full-dose THP-COP therapy for elderly patients with newly diagnosed, advanced-stage, aggressive non-Hodgkin lymphoma.

The cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) regimen, containing doxorubicin (DXR), which is a key drug for aggressive non-Hodgkin lymphoma (NHL), is a standard chemotherapeutic regimen; however, its administration in elderly patients is often intolerable. Pirarubicin (tetrahydropyranyl adriamycin [THP]) is an anthracycline developed in Japan. We have conducted a phase II trial of a full-dose THP-COP (modified CHOP regimen with DXR replaced by THP) regimen for elderly patients with newly diagnosed, advanced-stage, aggressive NHL. Patients aged 70-79 years old with previously untreated NHL according to the Working Formulation (D through H and J), disease stage I with a bulky mass or stage II-IV, and performance status of 0-1 were eligible. The THP-COP regimen, which consisted of 750-mg/m2 cyclophosphamide, 50-mg/m2 THP, 1.4-mg/m2 vincristine (capped at 2.0 mg) on day 1, and 100-mg prednisolone daily on days 1 to 5, was delivered every 3 weeks for 6 cycles. The primary endpoint was complete response (CR) rate. Twenty-nine patients were enrolled in the study. The CR rate was 65.5% (95% confidence interval, 45.7-82.1%). The 3-year failure-free and overall survival rates were 54.1% and 53.9%, respectively. The most frequent observed grade 3 or 4 toxicity was neutropenia, which occurred in 80% of the patients. Grade 3 cardiac dysfunction was observed in one patient. The full-dose THP-COP regimen exhibited similar efficacy and safety, and a tendency for less cardiac toxicity, when compared with the standard CHOP regimen in elderly Japanese patients with newly diagnosed, advanced-stage, aggressive NHL.

9p24.1 Genetic Alteration and PD-L1 Expression Are Characteristic of De Novo and Methotrexate-associated Epstein-Barr Virus-positive Hodgkin Lymphoma, But Not Methotrexate-associated Hodgkin-like Lesions.

Although the alteration of the 9p24.1 chromosome locus and PD-L1 overexpression is found in nodular sclerosis classic Hodgkin lymphoma, whether these aberrations occur in CHL and Hodgkin-like lesion (HLL) of methotrexate-associated lymphoproliferative disorder (MTX-CHL and MTX-HLL) is unknown. We compared the clinicopathologic features, the genomic status of the 9p24.1 locus and PD-L1 expression in a series of 34 patients including 17 with Epstein-Barr virus-positive de novo CHL, 7 with MTX-CHL, 10 with MTX-HLL using an immunofluorescence in situ hybridization method and immunohistochemistry. The proportions of cells with 9p24.1 genetic alteration in CD30-positive Hodgkin/Reed-Sternberg cells of de novo CHL, MTX-CHL and MTX-HLL were 55%, 68%, and 24%, respectively. The positive rates of PD-L1 measured by immunohistochemical H-scores of de novo CHL, MTX-CHL and MTX-HLL were 142±38, 157±75, and 70±42, respectively. Alteration of the 9p24.1 gene and expression of PD-L1 protein were correlated with all 3 diseases (correlation coefficient, 0.731). Both alteration of the 9p24.1 gene and overexpression of PD-L1 protein were observed in Epstein-Barr virus-positive de novo CHL and MTX-CHL but not in MTX-HLL. In conclusion, MTX-CHL has similar pathogenesis-like de novo CHL, but MTX-HLL seems to be a different disease from de novo CHL and MTX-CHL.

Clinicopathological analysis of follicular lymphoma with BCL2, BCL6, and MYC rearrangements.

Most follicular lymphomas (FL) show t(14;18)/IGH-BCL2 translocation, but rearrangement (R) negative cases exist. A series of 140 FL patients with a BCL2, BCL6, and MYC gene status examined by fluorescence in situ hybridization (FISH) were classified into five groups: (a) BCL2-R group (BCL2-R/BCL6-G/MYC-G) (G, germline), 77 cases; (b) BCL2/BCL6 double-R group (BCL2-R/BCL6-R/MYC-G), 16 cases; (c) BCL6-R group (BCL2-G/BCL6-R/MYC-G), 16 cases; (d) MYC-R group (BCL2-R or G/BCL6-R or G/MYC-R), three cases; (e) Triple-G group (BCL2-G/BCL6-G/MYC-G), 28 cases. The BCL6-R group had different clinicopathological characteristics. It showed lower rates of an advanced clinical stage and bone marrow invasion, less disease progression (p = 0.036), and a 'trend' toward a favorable progression-free survival (PFS) (p = 0.06). It also showed higher rates of grade 3A and MUM1-expression, and when analyzing the interfollicular spread pattern of CD20-positive cells, had fewer cases showing the IF3+ pattern (high interfollicular spread). Moreover, cases with BCL6-R and/or BCL6 gain (with cases of BCL2 rearrangement and/or of copy number gain excluded) correlated with favorable PFS (p = 0.014) and less IF3+ pattern (p = 0.007). We demonstrated that BCL6-R FLs showed unique clinicopathological findings, and FISH of BCL2, BCL6, and MYC is useful for FL diagnosis and clinical management.

Association between measurable residual disease kinetics and outcomes of Philadelphia chromosome-positive acute lymphoblastic leukemia.

The prognosis of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL) has improved dramatically. Although measurable residual disease (MRD) kinetics during pretransplant treatment has been recently reported to correlate with patient outcomes, it is unclear whether prognosis is better if the MRD falls below the detection sensitivity soon after induction therapy. We retrospectively analyzed data of 37 Ph + ALL patients who were treated with autologous or allogeneic stem cell transplantation (auto-SCT, allo-SCT) at our institute from 2003 to 2019. Based on MRD kinetics, patients were divided into three groups: early responders (MRD became negative after induction therapy [n = 10, 27.0%]); late responders (MRD remained positive after induction therapy and became negative just before SCT [n = 12, 32.4%]); and poor responders (MRD was positive until just before SCT [n = 15, 40.5%]). The 5-year disease-free survival (DFS) rates for the three groups were 80.0%, 60.0%, and 29.9%, respectively (P = 0.037). The 5-year overall survival rates were not significantly different. The 5-year relapse rates were 0.0%, 31.7%, and 49.5%, respectively (P = 0.045). Non-relapse mortality (NRM) rates were similar among the three groups. Subgroup analysis for the cases that received posttransplantation tyrosine kinase inhibitor maintenance therapy revealed that DFS was similarly dependent on MRD kinetics (P = 0.022). This study clarified that MRD kinetics was a significant prognosticator for DFS and relapse rate in Ph + ALL.

A multicenter, phase II study of R-THP-COP therapy for elderly patients with newly diagnosed, advanced-stage, indolent B-cell lymphoma.

The optimal combined chemotherapy regimen with rituximab has yet to be established for elderly patients with advanced-stage indolent B-cell lymphoma (B-NHL). A multicenter study was performed to evaluate the efficacy and toxicity of R-THP-COP therapy in elderly patients (aged 70-79 years) with newly diagnosed advanced-stage indolent B-NHL using the complete response rate (%CR) as the primary endpoint. Patients with newly diagnosed, clinical stage III/IV, indolent B-NHL, aged 70-79 years, with a performance status of 0-2 were eligible for this study. R-THP-COP consists of 375 mg/m2 of rituximab, 50 mg/m2 of pirarubicin, 750 mg/m2 of cyclophosphamide, 1.4 mg/m2 of vincristine, and 100 mg/day of oral prednisolone for 5 days. This study was discontinued due to poor accrual after the enrollment of 18 patients, although the planned sample size was 40 patients. The numbers of patients with follicular lymphoma, mucosa-associated lymphoid tissue lymphoma, and mantle cell lymphoma were 16, 1, and 1, respectively. The median age was 73 (range, 70 to 79) years. The %CR including unconfirmed CR was 45% (95% confidence interval: 25-66%) and the overall response rate was 72%. The estimated 5-year overall survival and progression-free survival rates were 55% and 28%, respectively. The major toxicity observed was grade 4 neutropenia (94%). Grade 4 non-hematological toxicities were not observed and no patients developed grade 3/4 cardiac toxicities. This phase II study provides useful information regarding the efficacy and toxicity of R-THP-COP therapy for patients aged 70 years or older with newly diagnosed, advanced-stage, indolent B-NHL, although the sample size was small.

[Optimization of rituximab dosing schedule in R-CHOP therapy for diffuse large B-cell lymphoma].

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma subtype, and nearly 70% of patients may be cured by administering R-CHOP therapy. However, R-CHOP is found to be inadequate in approximately one-third of the DLBCL cases, and refractory disease to R-CHOP is usually associated with a major cause of mortality. Therefore, it is essential to improve the efficacy of initial treatment in order to avoid unfavorable outcomes in patients with refractory DLBCL. In general, R-CHOP comprises of CHOP regimen that is repeated every 3 weeks and adding one-dose rituximab in each cycle. Although this combination method of rituximab with CHOP is effective and convenient, it does not contain enough scientific rationale and the schedule of rituximab administration has not been optimized. The pharmacokinetics of rituximab differs substantially among individuals and its serum half-life is approximately more than 500 hours; therefore, the peak concentration increases cumulatively by weekly infusion. A previous study revealed that patients with high blood concentration of rituximab showed higher response rate and longer progression-free survival. These findings suggest that the retention of higher levels of rituximab concentration and combination with chemotherapy during an early treatment period may bring about improvement of treatment effect. The HOVON group and Japan Clinical Oncology Group conducted randomized phase III studies to evaluate the efficacy of the dose-dense rituximab strategy for untreated DLBCL.

Single response assessment of transplant-ineligible multiple myeloma: a supplementary analysis of JCOG1105 (JCOG1105S1).

BACKGROUND: The International Myeloma Working Group response criteria require two consecutive assessments of paraprotein levels. We conducted an exploratory analysis to evaluate whether a single response assessment could be a substitute for the International Myeloma Working Group criteria using data from JCOG1105, a randomized phase II study on melphalan, prednisolone and bortezomib. METHODS: Of 91 patients with transplant-ineligible newly diagnosed multiple myeloma, 79 patients were included. We calculated the kappa coefficient to evaluate the degree of agreement between the International Myeloma Working Group criteria and the single response assessment. RESULTS: Based on the International Myeloma Working Group criteria, 11 (13.9%), 20 (25.3%), 36 (45.6%) and 12 (15.2%) patients had stringent complete response/complete response, very good partial response, partial response and stable disease, respectively. Based on the single response assessment, 17 (21.5%), 19 (24.1%), 35 (44.3%) and 8 (10.1%) patients had stringent complete response/complete response, very good partial response, partial response and stable disease, respectively. The kappa coefficient was 0.76 (95% confidence interval, 0.65-0.88), demonstrating good agreement. The single response assessment was not inferior to the International Myeloma Working Group criteria in the median progression-free survival (3.8 and 2.9 years) in stringent complete response/complete response patients, suggesting that the single response assessment was not an overestimation. CONCLUSIONS: The single response assessment could be a substitute for the current International Myeloma Working Group criteria for transplant-ineligible newly diagnosed multiple myeloma.

A randomized phase 2/3 study of R-CHOP vs CHOP combined with dose-dense rituximab for DLBCL: the JCOG0601 trial.

Rituximab plus cyclophosphamide-doxorubicin-vincristine-prednisone (R-CHOP) is the standard of care for untreated diffuse large B-cell lymphoma (DLBCL). However, the schedule for rituximab administration has not been optimized. To compare standard R-CHOP with CHOP plus dose-dense weekly rituximab (RW-CHOP) in patients with untreated DLBCL, we conducted a phase 2/3 study (JCOG0601, jRCTs031180139). Patients were randomly assigned to R-CHOP (CHOP-21 with 8 doses of rituximab once every 3 weeks [375 mg/m2]) or RW-CHOP (CHOP-21 with 8 doses of weekly rituximab [375 mg/m2]) groups. The primary end point of the phase 2 component was percent complete response (%CR) of the RW-CHOP arm, whereas that of the phase 3 component was progression-free survival (PFS). Between December 2007 and December 2014, 421 untreated patients were randomly assigned to R-CHOP (213 patients) or RW-CHOP (208 patients). The %CR in the RW-CHOP arm was 85.3% and therefore met the prespecified decision criteria for the phase 2 component. With a median follow-up of 63.4 months, the 3-year PFS and overall survival were 79.2% and 88.7% in the R-CHOP arm and 80.3% and 90.4% in the RW-CHOP arm, respectively. There was no significant difference in PFS (hazard ratio, 0.95; 90.6% confidence interval, 0.68-1.31). Although the safety profile and efficacy of RW-CHOP was comparable with R-CHOP and its tolerability was acceptable, weekly rituximab in combination with CHOP during the early treatment period did not improve PFS in untreated patients with DLBCL. This trial was registered at jrct.niph.go.jp as #jRCTs031180139.

A case of JAK2V617F-positive essential thrombocythemia where allele burden was reduced by a PD-1 inhibitor.

The Janus kinase/signal transducers and activators of transcription signaling pathway induces programmed death ligand-1 (PD-L1) expression. JAK2 mutation at position 617 (JAK2V617) is a frequent driver of myeloproliferative neoplasms (MPN) through PD-L1 expression. Although PD-1 inhibitors should be effective against MPN with JAK2V617F mutation, this has not yet been reported in humans. Thus, we assessed the efficacy of a PD-1 inhibitor in a lung cancer patient with JAK2V617F-positive essential thrombocythemia (ET). A 71-year-old man was diagnosed with ET, and with lung carcinoma 3 years later. After right lobectomy and postoperative chemotherapy, pembrolizumab [a PD-1 inhibitor (200 mg, every 3 weeks)] was initiated for refractory lung carcinoma. Lung cancer progression did not occur for 1.5 years under treatment. Most megakaryocytes were PD-L1-positive, and after pembrolizumab initiation, platelet count remained below 45 × 104/µL without the need for other cytoreductive therapies for ET. The JAK2V617F allele burden gradually decreased from 11.5% at diagnosis to 2.9% after 17 months of pembrolizumab treatment. Other peripheral blood lineages did not decrease, and pembrolizumab treatment was continued without any adverse events. This is the first report demonstrating the effectiveness of pembrolizumab in an MPN patient with JAK2V617F mutation.

The Role of Hypertension and Renin-angiotensin-aldosterone System Inhibitors in Bleomycin-induced Lung Injury.

INTRODUCTION: The risk factors for bleomycin-induced lung injury (BLI), a fatal complication of cancer chemotherapy, are not well-established. The renin-angiotensin-aldosterone system (RAAS) has recently been suggested to play a role in the development of lung injury. This study clarified the impact of hypertension (HTN) and the administration of RAAS inhibitors on BLI occurrence in patients treated with bleomycin-containing regimens. PATIENTS AND METHODS: We retrospectively analyzed the data of 190 patients treated with a bleomycin-containing regimen for Hodgkin lymphoma or germ cell tumors at our institutions from 2004 to 2018. RESULTS: Overall, 190 patients received bleomycin, and symptomatic BLI occurred in 21 (11.1%) cases. In the multivariate analysis, age ≥ 65 years (odd ratio, 10.90; 95% confidence interval, 3.72-32.20; P < .001) and history of HTN (odds ratio, 3.32; 95% confidence interval, 1.07-10.30; P = .04) were found to be significant risk factors for BLI onset. BLI occurred in 3.6% (n = 5) of patients with no risk, 11.8% (n = 2) of those whose only risk factor was HTN, 31.6% (n = 6) of those whose only risk factor was age ≥ 65 years, and 57.1% (n = 8) of those with both risk factors (P < .001). BLI-induced mortality rates in each group were 0.0% (n = 0), 5.9% (n = 1), 10.5% (n = 2), and 42.9% (n = 6) (P < .001), respectively. Among 31 patients with HTN, BLI incidence was 12.5% in patients who were administered RAAS inhibitors and 53.3% in those who were not (P = .02). CONCLUSION: Older age and history of HTN were independent risk factors for the development of BLI, and the administration of RAAS inhibitors might reduce the onset of BLI.

Clinicopathological evaluation of methotrexate-associated lymphoproliferative disorders with special focus on Epstein-Barr virus-positive mucocutaneous lesions.

Some patients diagnosed with methotrexate-associated lymphoproliferative disorder (MTX-LPD) develop spontaneous regression upon the discontinuation of MTX, whereas others require chemotherapy. The mechanisms underlying this differential response and the capacity to spontaneously regress are not clearly understood. We evaluated numerous clinicopathological features in 63 patients diagnosed with MTX-LPD, with a special focus on those with Epstein-Barr virus (EBV)-positive mucocutaneous lesions (EBVMCL). The diagnosis of EBVMCL included cases of both EBV-positive mucocutaneous ulcers (EBVMCU) and diffuse gingival swelling associated with proliferation of EBV-positive large B-cells. Of the four subgroups of MTX-LPD, one-year treatment-free survival (TFS) after the discontinuation of MTX was achieved among those with EBVMCL (100%), diffuse large B-cell lymphoma (57%), Hodgkin-like lesions (60%), or classical Hodgkin lymphoma (29%); a significant difference in TFS was observed when comparing the responses of patients with EBVMCL to the those diagnosed with other subtypes. Multivariate analysis revealed predictive factors for prolonged TFS that included EBV-positive lesions and comparatively low levels of serum LDH. Taken together, our study suggests that a diagnosis of EBVMCL is related to the overall clinical outcome after the discontinuation of MTX.

[Diffuse large B-cell lymphoma: standard treatment and research questions].

In 2018 the practical guidelines for hematological malignancies, edited by Japanese Society of Hematology, underwent major revision for the first time in five years. R-CHOP (rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) remains the standard treatment for diffuse large B-cell lymphoma (DLBCL) in line with the prior 2013 guidelines. R-CHOP has been considered as the standard treatment for DLBCL since early 2000s, when a 20% improvement in survival was observed when adding rituximab to CHOP. Following this, several clinical trials were conducted, but most attempts to exceed R-CHOP have failed. Moreover, this evidence has raised further research questions. In this report, the current evidence and the problems associated with DLBCL treatments have been reviewed.

A multicenter phase I study of inebilizumab, a humanized anti-CD19 monoclonal antibody, in Japanese patients with relapsed or refractory B-cell lymphoma and multiple myeloma.

This multicenter, phase I, open-label dose escalation study evaluated safety, tolerability, pharmacokinetics, and preliminary anti-tumor activity of inebilizumab in Japanese patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL), chronic lymphocytic leukemia (CLL), follicular lymphoma (FL), or multiple myeloma (MM) who were ineligible for hematopoietic stem cell transplantation. Patients received inebilizumab 2, 4, or 8 mg/kg intravenously on days 1 and 8 of the first 28-day cycle, and once every 28 days thereafter, with a 12 mg/kg cohort added. Twenty patients (11 FL, six DLBCL, two CLL, and one MM) received inebilizumab at four dose levels (2 mg/kg cohort, n = 3; 4 mg/kg cohort, n = 7; 8 mg/kg cohort, n = 4; 12 mg/kg cohort, n = 6). Three patients experienced dose-limiting toxicities: grade 4 neutropenia/grade 3 leukopenia (n = 1, 12 mg/kg) and grade 3 infusion reaction (n = 1 each, 4 mg/kg and 12 mg/kg); the maximum tolerated dose was 8 mg/kg. Four (three FL and one DLBCL) patients achieved complete response; eight (six FL and two DLBCL) achieved partial response. Overall response rate was 60%. Over the dose ranges evaluated, the pharmacokinetic profile of inebilizumab in Japanese patients was generally dose proportional. This phase I study showed acceptable toxicity and preliminary and promising efficacy of inebilizumab in patients with relapsed/refractory FL and DLBCL.

Phase I study of tirabrutinib (ONO-4059/GS-4059) in patients with relapsed or refractory B-cell malignancies in Japan.

We evaluated the safety, efficacy, pharmacokinetics, pharmacodynamics and predictive biomarkers of tirabrutinib, a second-generation, enhanced-selectivity Bruton's tyrosine kinase inhibitor in Japanese patients with relapsed/refractory B-cell non-Hodgkin lymphoma (B-cell NHL) and chronic lymphocytic leukemia (CLL). This was an open-label, multicenter, phase I study. Seventeen patients (male N = 8) with a median age of 70 years were enrolled in 4 dose cohorts (160 mg once daily [N = 3], 320 mg once daily [N = 3], 480 mg once daily [N = 4] and 300 mg twice daily [N = 7]); 4 patients had continued tirabrutinib administration as of 4 January 2018. The maximum tolerated dose was not reached. Pneumonitis (N = 1) was the dose-limiting toxicity for 300 mg twice daily. Common adverse events (AEs) were rash (35.3%) and vomiting (29.4%). Eight patients (47.1%) developed grade ≥3 AEs: neutropenia (23.5%), anemia (11.8%) and leukopenia (11.8%) were frequent. The overall response rate (≥PR) was 76.5% (13/17 patients), including 4 DLBCL patients with no CD79A/B or MYD88 mutations, and 1 CLL patient with a TP53 mutation, providing promising data for future developments. Of 16 patients with measurable lesions during the screening period, 12 showed ≥50% reductions in tumor diameter. In many patients, the tumor size decreased soon after beginning treatment. The maximum serum concentration for tirabrutinib was 611, 1220, 1280 and 886 ng/mL on Day 1 and 484, 971 1940, and 961 ng/mL on Day 28 for Cohorts 1-4, respectively. Tirabrutinib pharmacokinetics were linear, with little accumulation following multiple doses. Tirabrutinib was well tolerated and showed promising efficacy for B-cell NHL/CLL.

Safety, tolerability and pharmacokinetics of shorter duration of infusion of obinutuzumab in Japanese patients with B-cell non-Hodgkin lymphoma: final results of the phase II GATS study.

BACKGROUND: Shorter duration of infusion of monoclonal antibody treatments may reduce treatment burden and improve healthcare resource utilization. METHODS: This phase II study recruited Japanese patients with previously untreated CD20+ B-cell non-Hodgkin lymphoma. Patients received intravenous obinutuzumab 1000 mg by regular infusion on Days 1, 8 and 15 of Cycle 1, followed by 90-min shorter duration of infusion in up to seven subsequent cycles, provided they received ≥3 regular infusions without any grade ≥3 infusion-related reactions and had a lymphocyte count <5.0 × 109 cells/l. Standard cyclophosphamide, doxorubicin, vincristine and prednisolone chemotherapy was given in Cycles 1-6. The primary endpoints were as follows: incidence of grade ≥3 infusion-related reactions in Cycle 2 in patients who started shorter duration of infusion in Cycle 2, serum obinutuzumab concentrations and pharmacokinetic parameters and the time course of cytokine release. Adverse events and serious adverse events were monitored. RESULTS: Of 35 patients treated, 28 completed eight cycles; 31 started shorter duration of infusion in Cycle 2 and two patients in subsequent cycles. Two patients discontinued before starting shorter duration of infusion. No grade ≥3 infusion-related reactions occurred in Cycle 2. Twenty-one infusion-related reactions (all grades 1-2) were reported in 17/35 (49%) patients overall, mostly in Cycle 1 (18/21 infusion-related reactions [86%]). Grade ≥3 AEs occurring in ≥10% of patients included neutropenia/neutrophil count decreased (66%) and leukopenia/white blood cell count decreased (23%). Steady-state pharmacokinetics of obinutuzumab were attained in Cycle 2 and were not affected by shorter duration of infusion. No relevant cytokine elevations were reported with shorter duration of infusion. CONCLUSIONS: Regular infusion and shorter duration of infusion of obinutuzumab have comparable tolerability and pharmacokinetics in Japanese patients.