Abstract: Introduction Achievement of deep molecular response (DMR) has become an important treatment goal for patients with chronic phase chronic myeloid leukemia (CP-CML) since it is considered to be necessary for the challenge of stopping tyrosine kinase inhibitor (TKI) treatment. However, prognostic marker for prediction of DMR has not been established. We have previously reported the results of D-First study that shorter having time of BCR-ABL1 transcripts and early cytotoxic lymphocyte expansion were associated with achievement of DMR in newly diagnosed CP-CML patients treated with dasatinib. Here, the long-term follow-up results of the study were analyzed after a minimum 36 months follow-up. In this analysis, we mainly focus on dynamics of regulatory T cells (Treg) influencing patients' clinical course, as well as immunoprofiles during dasatinib treatment. Methods: A total of 52 patients with newly diagnosed CP-CML who were enrolled between June 2011 and June 2012 and treated with dasatinib 100 mg once daily on an open-label, multicenter, prospective phase II clinical trial (NCT01464411). All patients were followed-up for minimum of 36 months. Patients were assessed for molecular response before and 1, 3, 6, 9, 12, 15, 18, 24, and 36 months after starting dasatinib by real-time quantitative polymerase chain reaction analysis of BCR-ABL1 transcripts standardized on an international scale (BCR-ABL1 IS). A DMR was defined as less than 0.01% BCR-ABL1IS (MR4). The analysis of immunophenotyping of lymphocyte fractions in the peripheral blood samples was performed by flow cytometry before and 1, 2, 3, 6, 9, 12, 15, 18, 24, and 36 months after starting dasatinib treatment at a centralized laboratory (BML). Results: Patients' characteristic at diagnosis has been reported previously. Briefly, the median age was 52 years. High Sokal risk score was seen in 12% patients. With a minimum follow-up of 36 months, 12 (23%) patients have discontinued therapy. Reasons for treatment discontinuation includes: pleural effusion (N=3), pericardial effusion (1), proteinurea and systemic edema (1), pulmonary hypertension (1), malaise (1), elevation of intraocular pressure (1), interstitial pneumonia (1), and patient's requests (3). A cumulative rate of MMR was 75% by 12 months, 80% by 18 months, 86% by 24 months and 88% by 36 months. A cumulative rate of DMR was 49% by 12 months, 59% by 18 months, 59% by 24 months, and 65% by 36 months. Two patients died because of reasons unrelated to CML. No patients progressed to accelerated or blastic phase. Three-year overall survival was 96%. Flow cytometric analysis of peripheral blood revealed that average number of CD4+ T lymphocytes did not change over the course of 36 months. In contrast, ratio of CD4+CD25+CD127low Treg among CD4+ T cells decreased in a time-dependent manner during the follow-up. The ratio of Treg at 12 months of dasatinib treatment was associated with achievement of DMR, which was especially significant at 18 months (p 〈 0.05). Differentiated NK cell represented a trend of increasing during the period of observation according to the analysis of CD3-57+/CD3-56+ ratio. In addition, differentiation degree in NK cells assessed by CD3-57+/CD3-56+ ratio was negatively associated with the probability of Treg through the treatment period, suggesting a critical role of Treg inhibition by dasatinib for the induction of NK cell differentiation. Conclusion: The long term results from this study of dasatinib as frontline treatment of newly diagnosed CP-CML showed the excellent results of achieving DMR. Inhibition of Treg in peripheral blood, possibly induced by dasatinib, was associated with the achievement of DMR, which could be one of the prognostic markers for predicting the important treatment goal. Disclosures Yoshida: Pfizer: Honoraria, Speakers Bureau; Otsuka Pharmaceutical: Honoraria, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Speakers Bureau. Iriyama:Bristol-Myers Squibb: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau. Okamoto:Sumitomo Dainippon Pharma Co., Ltd.: Research Funding; Otsuka Pharmaceutical Co., Ltd.: Honoraria, Research Funding; Chugai Pharmaceutical Co., Ltd.: Research Funding; Shionogi & Co., Ltd.: Research Funding; Teijin Pharma Limited: Research Funding; Alexion Pharmaceuticals, Inc.: Research Funding; Eisai Co., Ltd.: Research Funding; Asahi Kasei Pharma Corp.: Research Funding; Bristol-Myers Squibb K.K.: Honoraria, Research Funding; Astellas Pharma Inc.: Research Funding; Toyama Chemical Co., Ltd.: Research Funding; Kyowa Hakko Kirin Co., Ltd.: Research Funding; Nippon Shinyaku Co., Ltd.: Research Funding; Pfizer Inc.: Honoraria, Research Funding; JCR Pharmaceuticals Co., Ltd.: Research Funding. Kumagai:Pfizer: Speakers Bureau; Novartis: Speakers Bureau; Bristol-Myers Squibb: Speakers Bureau. Ohyashiki:Bristol-Myers Squibb: Honoraria, Speakers Bureau; Novartis: Honoraria, Speakers Bureau; Ariad: Consultancy. Morita:Bristol-Myers Squibb: Speakers Bureau. Sakamoto:Takeda Pharmaceutical: Consultancy; Yakult: Other: Remuneration. Inokuchi:Bristol-Myers Squibb: Honoraria, Research Funding; Novartis: Honoraria; Celgene: Honoraria; Pfizer: Honoraria.

Abstract: Introduction: CD5+ DLBCL comprises 5-10% of DLBCL and is an immunohistochemical subgroup of DLBCL, not otherwise specified. CD5+ DLBCL shows a significantly worse survival than CD5-negative DLBCL with rituximab (R)-CHOP. Of note, central nervous system (CNS) relapse, particularly brain parenchymal relapse, frequently occurs even in the R-era (Miyazaki K, et al. Ann Oncol 2011). Most CD5+ DLBCL is classified as non-germinal center B-cell-like (non-GCB)/activated B-cell-like DLBCL. DA-EPOCH-R is reported to show promising outcomes in patients with newly diagnosed non-GCB DLBCL (Wilson WH, et al. J Clin Oncol 2008). High-dose methotrexate (HD-MTX) therapy has a greater potential than intrathecal administration of MTX to prevent brain parenchymal relapse. To explore a more effective treatment for newly diagnosed CD5+ DLBCL, we conducted a multicenter phase II study of DA-EPOCH-R combined with HD-MTX (PEARL5 study; UMIN000008507). Methods: Patients with newly diagnosed stage II-IV disease from 20 to 75 years of age with ECOG performance status (PS) of 0 to 3 were eligible for enrollment. CD5 expression in tumor cells was examined by immunohistochemistry and/or flow cytometry in participating institutes. Four cycles of DA-EPOCH-R followed by 2 cycles of HD-MTX (3.5 g/m2) and additional 4 cycles of DA-EPOCH-R were planned as the protocol treatment. The primary endpoint was 2-year progression-free survival. Secondary endpoints were complete response (CR) rate, overall response rate, 2-year overall survival, 2-year CNS recurrence, and toxicity. Response was assessed at each participating institute using the revised International Workshop Criteria. Toxicity was graded according to the Common Terminology Criteria for Adverse Events v4.0. This planned interim analysis included response and toxicity by the protocol treatment. Results: Forty-seven patients were enrolled between Aug 2012 and Nov 2015. The diagnosis of CD5+ DLBCL in all patients was confirmed by the central pathology review. Cyclin D1 and EBER were negative in all cases examined (n = 47 and n = 46, respectively). According to the Hans' criteria, 72% (33/46) of the patients had non-GCB DLBCL and 28% (13/46) had germinal center B-cell-like DLBCL. The median age was 62 years (range: 37-74 years), and 60% were 〉 60 years. The baseline clinical features were as follows: female sex, 62%; ECOG PS 〉 1, 4%; stage III/IV, 53%; elevated LDH, 66%; extranodal involvement 〉 1 site, 34%; bone marrow involvement, 11%; and high-intermediate-risk or high-risk groups of the International Prognostic Index, 47%. Skin/subcutaneous tissue was the most frequent site of extranodal involvement (15%). One patient had primary testicular DLBCL. Forty-six (99%) patients completed the protocol treatment. In the remaining patient, the protocol treatment was discontinued due to grade 3 stomatitis during the sixth cycle of DA-EPOCH-R. The median dose level of DA-EPOCH-R was 2 (range: 1-4). There was no deviation or violation in determining the dose levels of DA-EPOCH-R. At the time of this interim analysis, 46 patients were assessed for response. The CR rate was 91% (42/46; 95% confidence interval [CI], 79 - 98%) and the ORR was 93% (43/46; 95% CI, 82 - 99%). Two patients experienced disease progression during the treatment. Toxicity was assessed in 357 cycles of DA-EPOCH-R/HD-MTX in all 47 patients. There was no treatment-related death. Grade 4 non-hematologic toxicity was observed in only one patient who experienced tumor lysis syndrome with hyperkalemia soon after the first administration of R. The most common grade 3 non-hematologic toxicity was elevated alanine transaminase, which occurred in 6% of cycles. Two patients experienced grade 3 infection (cellulitis and endocarditis). Grade 3 neuropathy occurred in only 1% of cycles. There was no grade 3 cardiac toxicity. The targeted absolute neutrophil count ( 〉 500/mm3) occurred in 77% of cycles. Thrombocytopenia of 〈 25,000/mm3 occurred in 8% of cycles. Febrile neutropenia (FN), which occurred in 23% of cycles, was manageable. Conclusion: These interim results demonstrate that DA-EPOCH-R/HD-MTX provides a high CR rate in patients with newly diagnosed stage II-IV CD5+ DLBCL. This therapeutic approach was feasible, although most patients experienced FN during the protocol treatment. Disclosures Miyazaki: Eisai: Honoraria; Kyowa Kirin: Honoraria; Chugai: Honoraria. Asano:Jannsen: Honoraria; Chugai: Honoraria. Nishikori:Janssen Pharmaceutical: Honoraria; Eisai: Honoraria, Research Funding; Kyowa Kirin: Honoraria. Sunami:Daiichi Sankyo: Research Funding; Novartis: Research Funding; Celgene: Honoraria, Research Funding; Janssen Pharmaceutical: Research Funding; Sanofi: Research Funding; Bristol-Myers Squibb K.K.: Research Funding; Takeda: Research Funding; Ono Pharmaceutical: Research Funding. Yoshida:Kyowa Kirin: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Celgene: Honoraria; Mundipharma: Membership on an entity's Board of Directors or advisory committees. Tamaru:Kyowa Kirin: Honoraria. Izutsu:Abbvie: Research Funding; Gilead: Research Funding; Celgene: Research Funding; Janssen Pharmaceutical K.K.: Honoraria; Eisai: Honoraria; Kyowa Hakko Kirin: Honoraria; Chugai Pharmaceutical: Honoraria, Research Funding; Takeda Pharmaceutical: Honoraria; Mundipharma KK: Research Funding. Kinoshita:Kyowa Kirin: Honoraria; Janssen: Honoraria; Solasia: Research Funding; Gilead: Research Funding; Takeda: Research Funding; Ono: Research Funding; Chugai: Honoraria, Research Funding; Zenyaku: Honoraria, Research Funding; Eisai: Honoraria, Research Funding. Suzumiya:Toyama Chemical: Research Funding; Takeda: Honoraria; Eisai: Honoraria, Research Funding; Chugai: Honoraria, Research Funding; Kyowa Hakko kirin: Research Funding; Astellas: Research Funding. Nishikawa:Daiichi Sankyo: Honoraria, Research Funding; Sanofi: Honoraria. Katayama:Takeda: Honoraria; Pfizer: Honoraria; Bristol-Myers Squibb Japan: Honoraria; Alexion Pharmaceuticals: Honoraria; Celgene: Honoraria; Chugai: Honoraria, Research Funding; Astellas: Honoraria, Research Funding; Daiichi Sankyo: Honoraria; Kyowa Hakko Kirin: Honoraria, Research Funding; Taisho Toyama Pharma: Honoraria; Shire: Honoraria; Nippon Shinyaku: Honoraria; Eisai: Honoraria; Dainippon Sumitomo Pharma: Honoraria; Shionogi: Honoraria. Yamaguchi:Zenyaku: Honoraria; Chugai: Honoraria; Kyowa Kirin: Honoraria; Takeda: Honoraria; Eisai: Honoraria.

Abstract: Background : Nilotinib is a potent and selective inhibitor of BCR-ABL. In the Evaluating Nilotinib Efficacy and Safety in Clinical Trials-Newly Diagnosed Patients (ENESTnd) trial, frontline nilotinib therapy at 300 mg twice daily (BID) resulted in a higher rate of deep molecular response (DMR) compared to imatinib therapy in patients with chronic myelogenous leukemia in the chronic phase (CML-CP). Furthermore, in the ENESTxtend study, many patients with suboptimal response or treatment failure achieved a major molecular response (MMR) after the nilotinib dose was increased to 400 mg BID from 300 mg BID. The present study was aimed at investigating a strategy of intra-patient nilotinib dose escalation for patients with newly diagnosed CML-CP in order to achieve MR4.5early. Methods : N-Road is a multicenter phase II clinical study for patients with newly diagnosed CML-CP, in which nilotinib was administered at 300 mg BID for 24 months. In this study, increasing the nilotinib dose to 400 mg BID was allowed if patients satisfied the criteria for no optimal response at any time points. The criteria for no optimal response were defined as follows: BCR-ABL1 〉 10% on the International Scale [IS] after 3 months, BCR-ABL1 〉 1% on the IS after 6 months, BCR-ABL1 〉 0.1% on the IS after 12 months, BCR-ABL1 〉 0.0032% on the IS after 18 months, two consecutive losses of MMR, and two consecutive losses of MR4.5 (BCR-ABL1 ≤ 0.0032% on the IS). The primary endpoint was the cumulative MR4.5rate by 24 months after the initiation of nilotinib treatment. Results: Between August 2012 and July 2015, 53 Japanese patients were enrolled, of whom 51 were evaluated in the study. The median patient age was 50 years. The ratio of men to women was 33:18. The numbers of patients with low, intermediate, high Sokal risk scores was 21 (41.2%), 21 (41.2%), and 6 (11.8%), respectively, and 3 (5.9%) had an unknown risk. The median duration of nilotinib treatment was 23.8 months (range, 4.1-26.3 months). Of the patients, 33 (64.7%) completed 24 months of treatment, 7 (13.7%) had ongoing treatment, and 11 (21.6%) discontinued treatment because of adverse events (AEs; n=4), protocol deviation (n=1), loss to follow-up (n=3), death (n=1), insufficient effect (n=1), or consent withdrawal (n=1). The cumulative MR4.5 rate (95% confidence interval [CI]) in the 46 evaluable patients was 52.0% (36.9-69.0%) by 24 months (Figure). The cumulative MR4.0 and MMR rates were 60.9% (46.1-76.0%) and 83.5% (69.6-93.5%) by 24 months, respectively. Among the 46 evaluable patients, 26 satisfied the criteria for no optimal response. The dose was increased in 6 of the 26 patients but not in the remaining 20 patients for the following reasons,: hematological AEs (n=3), non-hematological AEs (n=9), achievement of MR4 at 18 months (n=2), patient refusal (n=4), and unknown (n=2). Although 4 patients with no optimal response achieved MR4.5, all of them did not receive an increased treatment dose. The actual mean dose intensities in the patients with or without optimal response were 570 and 560 mg/day, respectively. None of the patients had disease progression, and 1 patient died of an unknown cause during the study. The estimated rates (95% CI) of progression free survival and overall survival at 24 months were 98% (84-100%) and 98% (84-100%), respectively. The most common (≥20%) non-hematological AEs of any grade were rashes (47%), headache (34.2%), fatigue (21.6%) and nausea (23.5%). The most common (≥5%) grade 3/4 laboratory abnormalities were increased lipase (10.6%), decreased phosphate (12.2%) and increased alanine aminotransferase (7.8%). Cardiovascular events were observed to be ischemic heart disease in 2 patients (3.9%). Conclusion: In this study, it was difficult to evaluate the efficacy of nilotinib dose escalation to achieve MR4.5 early because the dose could not be increased to 400 mg BID in many patients who did not show optimal response. However, as we were unable to increase the dose to 400 mg BID in many patients because of AEs and as nilotinib therapy demonstrated superior MR4.5, these results might support continuous nilotinib therapy using a dosage of at least 300 mg BID for newly diagnosed CML. Disclosures Nishiwaki: Novartis PHARMA: Research Funding.

Abstract: We conducted a nationwide retrospective analysis of 116 hepatitis B virus (HBV) surface antigen (HBsAg)‐positive patients with diffuse large B‐cell lymphoma (DLBCL) and 278 HBsAg‐negative patients with DLBCL, as a control cohort, who received rituximab‐containing regimens as an induction chemotherapy at 30 Japanese medical centers between January 2004 and December 2014. Hepatitis was defined as an absolute serum alanine aminotransferase (ALT) level of ≥100 U/L. HBV reactivation‐related hepatitis was defined as hepatitis with an absolute serum HBV DNA level of ≥3.3 log IU/mL or an absolute increase of ≥2 log compared with the baseline value. HBsAg‐positive patients were divided into three groups based on anti–HBV prophylactic therapy: no nucleos(t)ide analogue (non–NA, n = 9), lamivudine (LAM, n = 20), and entecavir (ETV, n = 87). The 4‐year cumulative incidence (CI) of hepatitis in HBsAg‐positive and HBsAg‐negative patients was 21.1% and 14.6% ( P  = .081), respectively. The 4‐year CI of HBV reactivation‐related hepatitis was higher in HBsAg‐positive patients than in HBsAg‐negative patients (8.0% vs 0.4%; P   〈  .001). Among HBsAg‐positive patients, the 4‐year CI of HBV reactivation‐related hepatitis was the highest in the non–NA group (33.3%), followed by the LAM (15.0%) and ETV (3.8%) groups ( P   〈  .001). Of note, 3 non–NA patients (33%) and 1 LAM patient (5%) (but no ETV patients) died due to HBV hepatitis. Based on Cox multivariate analysis, HBsAg positivity was not associated with poor overall survival. Prophylactic use of ETV would reduce the occurrence of HBV reactivation‐related hepatitis and mortality in HBsAg‐positive DLBCL patients receiving rituximab‐containing chemotherapy.