Primary analysis of a prospective cohort study of Japanese patients with plasma cell neoplasms in the novel drug era (2016-2021).

The emergence of novel drugs has significantly improved outcomes of patients with plasma cell neoplasms (PCN). The Japanese Society of Hematology conducted a prospective observational study in newly diagnosed PCN patients between 2016 and 2021. The analysis focused on 1385 patients diagnosed with symptomatic PCN between 2016 and 2018. The primary endpoint was the 3-year overall survival (OS) rate among patients requiring treatment (n = 1284), which was 70.0% (95%CI 67.4-72.6%). Approximately 94% of these patients received novel drugs as frontline therapy. The 3-year OS rate was 90.3% (95%CI 86.6-93.1%) in the 25% of patients who received upfront autologous stem cell transplantation (ASCT), versus just 61.4% (95%CI 58.0-64.6%) in those who did not receive upfront ASCT. The only unfavorable prognostic factor that affected OS in ASCT recipients was an age of 65 or higher. For patients who did not receive ASCT, independent unfavorable prognostic factors included frontline treatment with conventional chemotherapies, international staging system score of 2/3, extramedullary tumors, and Freiberg comorbidity index of 2/3. This study unequivocally demonstrates that use of novel drugs improved OS in Japanese myeloma patients, and underscores the continued importance of upfront ASCT as the standard of care in the era of novel drugs.

ctDNA improves prognostic prediction in relapsed/refractory MM receiving ixazomib, lenalidomide, and dexamethasone.

It remains elusive how driver mutations, including those detected in circulating tumor DNA (ctDNA), affect prognosis in relapsed/refractory multiple myeloma (RRMM). Here we performed targeted-capture sequencing using bone marrow plasma cells (BMPC) and ctDNA of 261 RRMM cases uniformly treated with ixazomib, lenalidomide, and dexamethasone in a multicenter, prospective, observational study. We detected 24 and 47 recurrently mutated genes in BMPC and ctDNA, respectively. In addition to clonal hematopoiesis-associated mutations, varying proportion of driver mutations, particularly TP53 mutations (59.2% of mutated cases), were present in only ctDNA, suggesting their subclonal origin. In univariable analyses, ctDNA mutations of KRAS, TP53, DIS3, BRAF, NRAS, and ATM were associated with worse progression-free survival (PFS). BMPC mutations of TP53 and KRAS were associated with inferior PFS, while KRAS mutations were prognostically relevant only when detected in both BMPC and ctDNA. A total number of ctDNA mutations in the six relevant genes was a strong prognostic predictor (2-year PFS rates: 57.3%, 22.7%, and 0% for 0, 1, and ≥ 2 mutations, respectively) and independent of clinical factors and plasma DNA concentration. Using the number of ctDNA mutations, plasma DNA concentration, and clinical factors, we developed a prognostic index (ctRRMM-PI), classifying patients into three categories with 2-year PFS rates of 57.9%, 28.6%, and 0%. Serial analysis of ctDNA mutations in 94 cases revealed that TP53 and KRAS mutations frequently emerge after therapy. Thus, we clarify the genetic characteristics and clonal architecture of ctDNA mutations and demonstrate their superiority over BMPC mutations for prognostic prediction in RRMM.

An observational study of once-weekly carfilzomib in patients with multiple myeloma in Japan (Weekly-CAR study).

Background: The ARROW study demonstrated that once-weekly carfilzomib and dexamethasone (wKd) therapy significantly prolonged progression-free survival compared with twice-weekly carfilzomib and dexamethasone therapy in relapsed or refractory multiple myeloma patients. Aim: To describe the treatment patterns, effectiveness and safety of wKd therapy in real-world settings in Japan. Methods: We investigated data from the medical records of 126 Japanese patients with relapsed or refractory multiple myeloma. Results: The overall response rate was 66.3%. The median progression-free survival was 9.5 months. The incidence of treatment-emergent adverse events of any grade and grade ≥3 were 45.8 and 20.8%, respectively. Conclusion: There were no new or unexpected safety signals in this study. This study demonstrated the effectiveness and safety profiles of wKd therapy in Japan.

Carfilzomib became available for daily clinical practice as a drug for cancer of bone marrow (multiple myeloma) that comes back or does not respond to previous drug (relapsed or refractory). This drug was approved in the USA in 2012, and in Japan in 2016. In this study, we looked at how once-weekly carfilzomib works and how safe it is in real-life situations in Japan. We screened 126 patients with relapsed or refractory multiple myeloma in Japan. The median age of the patients was 70 years, with 25% being over 75 years. This study also included some patients who were not in the best overall health, had a history of many treatments or had heart complications. In 66.3% of patients, the cancer had disappeared or the extent of the cancer had reduced after treatment. Side effects and serious side effects occurred in 45.8 and 14.2% of patients, respectively. The most common side effects were low levels of blood platelets (9.2%), high blood pressure (5.8%), loose or watery stools (5.0%), fever (5.0%), and low levels of red blood cells (4.2%). Heart disorders occurred in five patients. But all patients recovered or improved with treatment such as blood pressure lowering drugs and diuretics. These results showed that once-weekly carfilzomib works well and is safe in real-world settings in Japan. This information can help us think about how to pick the right patients and handle heart disease risks when using carfilzomib treatment.

A prospective, multicenter, observational study of ixazomib plus lenalidomide-dexamethasone in patients with relapsed/refractory multiple myeloma in Japan.

Real-world studies permit inclusion of a more diverse patient population and provide more information on the effectiveness of treatments used in routine clinical practice. This prospective, multicenter, observational study investigated the effectiveness and safety of ixazomib plus lenalidomide and dexamethasone (IRd) in 295 patients with relapsed/refractory multiple myeloma (RRMM) in routine clinical practice in Japan. Patients had a median age of 74 years, 80.0% were aged ≥ 65 years, 42.0% had received ≥ 3 lines of prior treatment, and 28.5% were "frail" according to the International Myeloma Working Group frailty score. After a median follow-up of 25.0 months, median progression-free survival (PFS) was 15.3 (95% CI 12.4-19.5) months, while median overall survival was not reached. The overall response rate was 53.9%, and 31.5% of patients had a very good partial response or better. In the subgroup analysis, median PFS was better in patients with 1 versus 2 or ≥ 3 lines of prior treatment (29.0 vs 19.2 or 6.9 months) and paraprotein versus clinical relapse (16.0 vs 7.9 months), but median PFS was not notably affected by frailty score or age group. Dose adjustment was more frequent among patients aged > 75 years, especially early after IRd treatment initiation. Treatment-emergent adverse events (TEAEs) of any grade occurred in 84.4% of patients and 24.7% of patients discontinued treatment due to TEAEs; no new safety concerns were found. These findings suggest that oral IRd triplet regimen is an effective and tolerable treatment option for RRMM patients in real-world settings outside of clinical trials.ClinicalTrials.gov identifier: NCT03433001; Date of registration: 14 February 2018.

Importance of TKI treatment duration in treatment-free remission of chronic myeloid leukemia: results of the D-FREE study.

Treatment-free remission (TFR) is a new goal for patients with chronic myeloid leukemia in chronic phase (CML-CP) with a sustained deep molecular response (DMR) to treatment with tyrosine kinase inhibitors (TKIs). However, optimal conditions for successful TFR in patients treated with second-generation (2G)-TKIs are not fully defined. In this D-FREE study, treatment discontinuation was attempted in newly diagnosed CML-CP patients treated with the 2G-TKI dasatinib who achieved BCR-ABL1 levels of ≤ 0.0032% (MR4.5) on the international scale (BCR-ABL1IS) and maintained these levels for exactly 1 year. Of the 173 patients who received dasatinib induction therapy for up to 2 years, 123 completed and 60 (48.8%) reached MR 4.5. Among the first 21 patients who maintained MR4.5 for 1 year and discontinued dasatinib, 17 experienced molecular relapse defined as loss of major molecular response (BCR-ABL1IS > 0.1%) confirmed once, or loss of MR4 (BCR-ABL1IS > 0.01%) confirmed on 2 consecutive assessments. The estimated molecular relapse-free survival rate was 16.7% at 12 months. This study was prematurely terminated according to the protocol's safety monitoring criteria. The conclusion was that sustained DMR for just 1 year is insufficient for TFR in CML-CP patients receiving dasatinib for less than a total of 3 years of treatment.

The safety and efficacy of hematopoietic stem cell mobilization using biosimilar filgrastim in related donors.

In April 2014, the Japan Society for Hematopoietic Cell Transplantation started a prospective observational study entitled "A short-term follow-up investigation of related hematopoietic stem cell donors receiving biosimilar G-CSF to mobilize peripheral blood stem cells." A total of 106 donors were registered from 25 transplant facilities through the end of March 2017. The study cohort consisted of 47 men and 58 women, and their median age was 38.5 years (range 15-65 years). The mean total count of collected CD34-positive cells/recipient body weight for all 106 donors was 4.40 ± 2.38 × 10 6/kg. The yield of CD34-positive cells was weakly correlated with donor age was observed. However, gender, WBC count on day 4, G-CSF dose reduction, type of apheresis device, collection speed, and treated blood volume had no significant impact on the collection efficacy of CD34-positive cells. The safety profile of biosimilar G-CSF was also acceptable: 126 adverse events in 73 donors were reported, but none was serious. The most common adverse events were low back pain, headache, and bone pain. This prospective study confirmed that biosimilar G-CSF had comparable efficacy and safety to reference G-CSF for CD34-positive cell mobilization in healthy related donors.

Real-world experience of treatment with thrombopoietin receptor agonists in anti-thymocyte globulin-naïve patients with aplastic anemia: an observational retrospective analysis in a single institution.

OBJECTIVE: To explore the efficacy and safety of thrombopoietin receptor agonists (TPO-RAs) without anti-thymocyte globulin (ATG) in ATG-naïve patients with aplastic anemia (AA) in a real-world setting. METHODS: We retrospectively evaluated treatment outcomes in 45 consecutive ATG-naïve patients with AA who received TPO-RAs between 2017 and 2021 at our hospital. RESULTS: ATG ineligibility was due to advanced age (≥ 70 years), n = 22; not recommended under Japanese guidelines due to mild symptoms, n = 13; patient preference, n = 6; uncontrolled heart failure, n = 2; uncontrolled diabetes mellitus, n = 2; chronic renal failure, n = 2; invasive aspergillosis, n = 1. Twenty-eight patients (62%) achieved hematologic response in at least unilineage after 6 months' treatment, while 38 (84% in unilineage response-eligible patients) and four (25% in trilineage response-eligible patients) patients achieved at least unilineage and trilineage responses, respectively, at any point during the follow-up period. Five patients switched from eltrombopag to romiplostim because of adverse events or lack of efficacy, and two developed hematologic malignancies. Eltrombopag was effective even in elderly ATG-ineligible patients with severe AA. The 2-year overall survival rate was 84.3%, with a median 26.3-month follow-up. Time from diagnosis to eltrombopag treatment initiation tended to affect the response (p = 0.0727), but no factors that significantly predicted hematologic response were identified. CONCLUSIONS: We found eltrombopag to be effective even in elderly ATG-naïve patients with severe AA, indicating that TPO-RA treatment should be considered in patients ineligible for ATG treatment because of age, complications, or severe AA.

Screening for Gaucher Disease Using Dried Blood Spot Tests: A Japanese Multicenter, Cross-sectional Survey.

Objective For patients with Gaucher disease (GD), a rare, inherited lysosomal storage disease, obtaining a definitive diagnosis is currently time-consuming and costly. A simplified screening method to measure the glucocerebrosidase (GBA) activity using dried blood spots (DBS) on filter paper has recently been developed. Using this newly developed screening method, we evaluated real-world GD screening in patients suspected of having GD. Methods This multicenter, cross-sectional, observational study with a diagnostic intervention component evaluated real-world screening in patients suspected of having GD based on their clinical symptoms and a platelet count <120,000/µL. The endpoint was the number of patients with low GBA activity determined using DBS. Results In 994 patients who underwent initial DBS screening, 77 had low GBA activity. The assay was not repeated in 1 patient who was diagnosed as having a high possibility of GD due to clinical symptoms, and a further 21 patients completed the study without undergoing the second assay. Of the remaining 55 patients who had 2 DBS assays performed, 11 had a low GBA activity in both assays. Overall, DBS screening identified 12 (1.2%) patients with a low GBA activity, a proportion consistent with prior screening studies. Conclusion These results suggest that the simplified DBS method was less burdensome to patients, was easily utilized by many physicians, and could be a useful first-tier screening assay for GD prior to initiating burdensome genetic testing.

Consolidation with 90 Yttrium-ibritumomab tiuxetan after bendamustine and rituximab for relapsed follicular lymphoma.

Bendamustine and rituximab (BR) are widely used in patients with follicular lymphoma (FL) previously treated with conventional immunochemotherapy, but the role of consolidation radioimmunotherapy in these patients is unknown. This study evaluated the efficacy and safety of consolidation with 90 Yttrium-ibritumomab tiuxetan (90 Y-IT) after re-induction therapy with BR in patients with previously treated FL. This study included adult patients with relapsed FL who had undergone one or two prior therapies. Re-induction therapy with BR was administered every 4 weeks up to 4-6 cycles. If patients achieved at least partial response, 90 Y-IT was administered as consolidation therapy. The primary endpoint was 2-year progression-free survival (PFS) after consolidation. A total of 24 FL patients (median age 60 years) who had undergone one (n = 17) or two (n = 7) prior treatments received BR. After BR therapy, 22 patients proceeded to consolidation with 90 Y-IT, resulting in an overall 88% response rate to the protocol treatment. Within a median observation period of 46.8 months, the estimated 2-year PFS rate after the consolidation among the 22 patients receiving 90 Y-IT was 59% (95% confidence interval [CI], 38%-77%). Patients whose remission after previous treatment had lasted ≥2 years had a significantly higher 2-year PFS rate than patients whose remission after previous treatment had been <2 years (68% vs. 33%, Wilcoxon p = 0.0211). Major adverse events during the protocol treatment and within 2 years after the consolidation were hematological toxicities, but they were generally acceptable. Consequently, the estimated 2-year overall survival after the consolidation was 95% (95% CI, 74%-99%). In conclusion, in a subset of patients with previously treated FL, 90 Y-IT consolidation after BR re-induction conferred a durable remission, indicating that consolidation therapy using 90 Y-IT may be a novel therapeutic option for patients with relapsed FL (UMIN000008793).

Minimum-Dose, Short-Term Methotrexate With Tacrolimus for Graft-vs-Host Disease Prophylaxis Following Unrelated Cord Blood Transplantation in Adults: A Retrospective Analysis at a Single Institution.

BACKGROUND: Methotrexate (MTX) or mycophenolate mofetil with tacrolimus (TAC) is used for graft-vs-host disease (GVHD) prophylaxis in unrelated cord blood transplantation (CBT). However, there is no consensus regimen for GVHD prophylaxis in CBT. We aimed to assess the efficacy and feasibility of minimum-dose, short-term MTX (MS-MTX) for GVHD prophylaxis in CBT. METHODS: We retrospectively evaluated 35 consecutive adult patients who underwent CBT and received MS-MTX (6 mg/m2 day 1; 3 mg/m2 days 3 and 6, intravenously) with TAC for GVHD prophylaxis in our hospital between 2015 and 2019. Transplantation outcomes with respect to time to hematopoietic recovery, engraftment, incidence and severity of GVHD, adverse events, relapse, nonrelapse mortality (NRM), and overall survival were evaluated. RESULTS: The median time to neutrophil, platelet, and reticulocyte recovery was 22, 38, and 32 days, respectively. Cumulative neutrophil engraftment was 91.4%. After a median 3.2-year follow-up, the 2-year overall survival was 64.3%. The 2-year cumulative incidence of relapse and NRM was 20.4% and 14.9%, respectively. The 100-day cumulative incidence of grade II-IV acute GVHD and 2-year cumulative incidence of chronic GVHD were 28.6% and 36.6%, respectively. No grade IV acute GVHD was observed. Sixteen patients experienced oral mucositis and/or pharyngeal pain (46%; grades 1-2, n = 15; grade 3 pharyngeal pain, n = 1). No patients suffered from human herpesvirus 6 encephalitis/myelitis. CONCLUSIONS: MS-MTX with TAC is feasible and safe and yields lower rates of severe oropharyngeal mucositis and human herpesvirus 6 encephalitis/myelitis without increasing GVHD, graft failure, relapse, or NRM.

Efficacy and safety of micafungin in empiric and D-index-guided early antifungal therapy for febrile neutropenia; A subgroup analysis of the CEDMIC trial.

OBJECTIVES: The D-index is defined as the area over the neutrophil curve during neutropenia. The CEDMIC trial confirmed the noninferiority of D-index-guided early antifungal therapy (DET) using micafungin to empirical antifungal therapy (EAT). In this study, we evaluated the efficacy and safety of micafungin in these settings. METHODS: From the CEDMIC trial, we extracted 67 and 113 patients who received micafungin in the DET and EAT groups, respectively. Treatment success was defined as the fulfilment of all components of a five-part composite end point. Fever resolution was evaluated at seven days after the completion of therapy. RESULTS: The proportion of high-risk treatments including induction chemotherapy for acute leukemia and allogeneic hematopoietic stem cell transplantation was significantly higher in the DET group than in the EAT group (82.1% vs. 52.2%). The efficacy of micafungin was 68.7% (95%CI: 56.2-79.4) and 79.6% (71.0-86.6) in the DET and EAT groups, respectively. When we focused on high-risk treatments, the efficacy was 69.1% (55.2-80.9%) and 78.0% (65.3-87.7%), respectively (P = 0.30). There was no significant difference in any of the 5 components between the two groups. CONCLUSIONS: The efficacy of micafungin in patients undergoing high-risk treatment was not strongly impaired in DET compared to that in EAT.

Treatment-free remission after thrombopoietin receptor agonist discontinuation in patients with newly diagnosed immune thrombocytopenia: an observational retrospective analysis in real-world clinical practice.

Thrombopoietin receptor agonists (TPO-RAs) are used for treatment of chronic immune thrombocytopenia (ITP). Several studies have shown that TPO-RAs induce remission and sustained response, despite long-term discontinuation of therapy. Furthermore, TPO-RAs are effective in patients with newly diagnosed ITP. Here, we retrospectively assessed all patients with ITP who received TPO-RAs in our hospital, focusing on newly diagnosed, non-splenectomized patients who had discontinued TPO-RAs due to sustained complete response (CR, platelet count ≥ 100 × 109/L). Moreover, we explored predictive factors related to sustained treatment-free remission (TFR) without additional ITP treatment. Seventy-seven consecutive patients with ITP received TPO-RAs from 2011 to 2018. Twenty-seven newly diagnosed patients achieved CR and discontinued TPO-RAs. The overall response and discontinuation rates in all patients with ITP were 79.2% and 41.6%, respectively. In newly diagnosed patients who discontinued TPO-RAs, the 2-year TFR rate, cumulative incidence of loss of CR, and response (R) rate (platelet count ≥ 30 × 109/L) were 66.4%, 46.7%, and 34.0%, respectively. Patients who achieved R within 14 days from the start of TPO-RA administration exhibited a higher 2-year TFR rate, compared with patients who did not (87.5% vs. 48.5%, p = 0.0106). In conclusion, patients with newly diagnosed ITP who achieve sustained response should consider discontinuation of TPO-RAs.

Treatment outcomes of chronic-phase chronic myeloid leukemia with resistance and/or intolerance to a 1st-line tyrosine kinase inhibitor in Japan: the results of the New TARGET study 2nd-line.

We herein report the results of the New TARGET study 2nd-line, which collected data on patients with chronic-phase (CP) chronic myeloid leukemia (CML) who received a 2nd-line tyrosine kinase inhibitor (TKI) because of resistance and/or to a 1st-line TKI. A total of 98 patients were enrolled intolerance between April 2010 and March 2013, and 82 patients were analyzed. The median age was 54 years (range 22-88 years). Seventy-six patients (93%) received imatinib as the 1st-line TKI. Forty-five (55%) and 37 (45%) patients began nilotinib and dasatinib treatments at entry, respectively. First-line TKI treatment achieved complete hematological response in 79 patients (96%) and complete cytogenetic response (CCyR) in 49 patients (60%), respectively. Nine patients (11%) had BCR-ABL1 kinase domain point mutations at enrollment. The estimated 3-year progression-free-survival rate after enrollment was 98.7% (95% CI 91.1-99.8%). Overall, the probabilities of achieving CCyR and a major molecular response were 89.3% (95% CI 81.4-94.8%) and 87.2% (95% CI 78.1-93.8%), respectively. There were no new safety issues. This study demonstrated that CML-CP patients in Japan who are resistant and/or intolerant to a 1st-line TKI can achieve an extremely good outcome by 2nd-line TKI treatment.

D-Index-Guided Early Antifungal Therapy Versus Empiric Antifungal Therapy for Persistent Febrile Neutropenia: A Randomized Controlled Noninferiority Trial.

PURPOSE: Empiric antifungal therapy (EAT) is recommended for persistent febrile neutropenia (FN), but in most patients, it is associated with overtreatment. The D-index, calculated as the area surrounded by the neutrophil curve and the horizontal line at a neutrophil count of 500/µL, reflects both the duration and depth of neutropenia and enables real-time monitoring of the risk of invasive fungal infection in individual patients at no cost. We investigated a novel approach for patients with persistent FN called D-index-guided early antifungal therapy (DET), in which antifungal treatment is postponed until a D-index reaches 5,500 or the detection of positive serum or imaging tests, and compared it with EAT in this multicenter open-label noninferiority randomized controlled trial. PATIENTS AND METHODS: We randomly assigned 423 patients who underwent chemotherapy or hematopoietic stem-cell transplantation for hematologic malignancies to the EAT or DET group. The prophylactic use of antifungal agents other than polyenes, echinocandins, or voriconazole was allowed. Micafungin at 150 mg per day was administered as EAT or DET. RESULTS: In an intent-to-treat analysis of 413 patients, the incidence of probable/proven invasive fungal infection was 2.5% in the EAT group and 0.5% in the DET group, which fulfilled the predetermined criterion of noninferiority of the DET group (-2.0%; 90% CI, -4.0% to 0.1%). The survival rate was 98.0% versus 98.6% at day 42 and 96.4% versus 96.2% at day 84. The use of micafungin was significantly reduced in the DET group (60.2% v 32.5%; P < .001). CONCLUSION: A novel strategy, DET, decreased the use and cost of antifungal agents without increasing invasive fungal infections and can be a reasonable alternative to empiric or preemptive antifungal therapy.

Yttrium-90 ibritumomab tiuxetan consolidation versus rituximab maintenance therapy after induction chemotherapy in patients with indolent non-Hodgkin lymphoma: a single-institution experience.

OBJECTIVES: Indolent B-cell non-Hodgkin lymphomas (iNHLs) are considered incurable. Rituximab maintenance and yttrium-90 ibritumomab tiuxetan (90Y-IT) consolidation are promising post-remission therapies. However, only one randomized phase II trial has compared their efficacies and adverse effects. Here, we compared the efficacy and safety of 90Y-IT consolidation and rituximab maintenance in iNHL patients. METHODS: We retrospectively examined 75 iNHL patients with complete or partial response after initial chemotherapy between January 2008 and December 2018. Twenty-seven patients received 90Y-IT consolidation and 48 received rituximab maintenance (every 2 months for 2 years). Progression-free survival (PFS), overall survival (OS), and time to next treatment (TTNT) were estimated from the start of the treatment, and adverse effects were evaluated. RESULTS: After a median 3.6-year follow-up, the 5-year PFSs of the 90Y-IT consolidation and rituximab maintenance groups were 75.5% and 82.4%, respectively (log-rank test, p = 0.839), and the 5-year OSs were 100% and 97.8%, respectively (log-rank test, p = 0.465). The corresponding median TTNTs were not reached (log-rank test, p = 0.804). The commonest adverse effect with 90Y-IT consolidation was hematotoxicity; lower rates and grades of cytopenia were observed in patients who received rituximab maintenance. Secondary malignancies were observed in 1 patient (4%) who received 90Y-IT consolidation and 2 patients (4.2%) who received rituximab maintenance (Fisher's exact test, p > 0.99). CONCLUSION: 90Y-IT consolidation and rituximab maintenance were similar with respect to PFS, OS, and TTNT. However, the features and grades of adverse effects significantly differed. Patient-specific characteristics should be considered when deciding post-remission treatments.

Outcomes of unplanned tyrosine kinase inhibitor discontinuation in patients with chronic myeloid leukemia: retrospective analysis of real-world experience in a single institution.

OBJECTIVES: To explore real-world prognoses for tyrosine kinase inhibitor (TKI) discontinuation in chronic myeloid leukemia (CML) patients and the associated reasons for TKI discontinuation. METHODS: We investigated, using the medical records of 85 consecutive CML patients who received TKIs between December 2001 and August 2016 at our hospital, reasons for discontinuation, duration of TKI treatment before discontinuation, molecular response (MR) status at TKI discontinuation, treatment-free remission (TFR) duration, and overall survival after TKI discontinuation. RESULTS: TKI therapy was discontinued in 21 patients. The median treatment duration before discontinuation was 68.3 months. The response statuses at discontinuation were MR4 (n = 2), MR4.5 (n = 4), and ≥MR5 (n = 15). The reasons were pleural effusion (n = 5); requests for prolonged deep molecular response (DMR) (n = 4); ischemic heart disease, anemia, and economic problems (each, n = 3); renal dysfunction (n = 2); and hyperkalemia, diarrhea, dementia, asthma, and desire to get pregnant, (each, n = 1). All patients were alive with median follow-up period of 32.1 months. TFR was maintained in 14 patients, and the 2-year TFR proportion was 66.7%. Seven patients restarted TKI therapy and achieved MR4 within median of 3 months. The duration of TKI administration before discontinuation (≥ 70 months) was favored longer TFR durations. CONCLUSION: TKI was safely discontinued in clinical practice and yielded TFR rates similar to those observed in previous clinical trials, regardless of reason. Achievement of TFR significantly impacts patients' quality of life and should be considered in clinical practice.

[Efficacy and safety of biosimilar filgrastim for autologous peripheral blood stem cell harvest and transplantation: a single-institutional retrospective analysis].

Three biosimilar filgrastim products are currently available in Japan. Among these, the safety and efficacy of two imported drugs for autologous peripheral blood stem cell harvest (autoPBSCH) and autologous peripheral blood stem cell transplantation (autoPBSCT) have been studied widely; however, evidence of the safety and efficacy of domestically manufactured filgrastim is limited. Therefore, we compared the efficacy and safety of domestic biosimilar filgrastim (BF1, n=23) with those of originator filgrastim (OF, n=21) for autoPBSCH and autoPBSCT. Before autoPBSCH, the same median total dose of 3.3 mg filgrastim was administered to patients in the BF1 and OF groups. Median numbers of CD34-positive cells harvested did not significantly differ between BF1 (4.32×106/kg) and OF (4.75×106/kg) groups. After autoPBSCT, the median total doses of BF1 and OF used for neutrophil recovery were 2.7 and 3.3 mg, respectively. There were no significant inter-group differences in the time to bone marrow recovery, total transfusion units, hospitalization duration, overall survival at 1 year, or adverse events. Compared with OF, the cost of BF1 was considerably lower by 229,529 yen per transplantation case. Thus, the efficacy and safety of BF1 were comparable to those of OF, making BF1 an effective and economical alternative to OF.

Bortezomib maintenance therapy in transplant-ineligible myeloma patients who plateaued after bortezomib-based induction therapy: a multicenter phase II clinical trial.

In the era of novel therapeutic agents for multiple myeloma (MM), both the significance of achieving the plateau phase and the efficacy of subsequent maintenance therapy remain unclear. In the present study, we evaluated the efficacy and safety of bortezomib maintenance therapy (biweekly for 1 year) in transplant-ineligible MM patients who plateaued after bortezomib-based induction therapy. Of 36 evaluable patients, the overall response rate during induction therapy was 61%, with a stringent complete response in 6%, a complete response in 6%, a very good partial response in 17%, and a partial response in 33%. Twenty patients achieved the plateau phase and subsequently received bortezomib maintenance therapy. Median progression-free survival from the induction and maintenance therapies was 13.8 months (95% confidence interval, 11.4-23.7 months) and 10.7 months (95% confidence interval, 3.7-10.7 months), respectively. During maintenance therapy, there were no cases with grade ≥ 2 peripheral neuropathy, nor was there any improvement in the quality of the response. In conclusion, although maintenance therapy with biweekly bortezomib for up to 1 year was feasible, plateau-oriented bortezomib induction therapy followed by bortezomib maintenance therapy was not adequate in newly diagnosed transplant-ineligible MM patients.