Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia Research Articles

Real-world outcomes of ponatinib treatment in 724 patients with CML and Ph+ ALL: a post-marketing surveillance study with a special interest in arterial occlusive events in Japan.

In September 2016, ponatinib was approved in Japan for the treatment of patients with chronic myeloid leukemia with resistance/intolerance to prior tyrosine kinase inhibitors and patients with relapsed or refractory Philadelphia chromosome-positive acute lymphoblastic leukemia. We conducted a post-marketing all-case surveillance to study the safety and efficacy of ponatinib in clinical practice, focusing on arterial occlusive events. Data from 724 patients were collected for 2years from the initiation of ponatinib. The arterial occlusive events were reported in 6.49% (47/724) with an exposure-adjusted incidence rate of 6.8/100 person-years. The risks associated with arterial occlusive events were age and comorbidities including hypertension and diabetes. At 104weeks, the cumulative major molecular response rate in patients with chronic-phase chronic myeloid leukemia was 67.2% and the complete cytogenetic response in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia was 80.0%. Furthermore, the estimated 1-year overall survival rate was 98.5% for chronic-phase chronic myeloid leukemia and 68.6% for Philadelphia chromosome-positive acute lymphoblastic leukemia. This surveillance demonstrated that ponatinib has a favorable safety and efficacy profile in Japanese patients and also showed the necessity of closely monitoring arterial occlusive events in older adults and patients with predisposing factors for atherosclerosis.

Ponatinib vs Imatinib in Frontline Philadelphia Chromosome–Positive Acute Lymphoblastic Leukemia

In newly diagnosed Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL), disease progression due to acquired resistance to first- or second-generation BCR::ABL1 tyrosine kinase inhibitors is common. Ponatinib inhibits BCR::ABL1 and all single-mutation variants, including T315I. To compare frontline ponatinib vs imatinib in adults with newly diagnosed Ph+ ALL. Global registrational, phase 3, open-label trial in adults aged 18 years or older with newly diagnosed Ph+ ALL. From January 2019 to May 2022, eligible patients at 77 sites were randomized 2:1 to ponatinib (30 mg/d) or imatinib (600 mg/d) with reduced-intensity chemotherapy, followed by single-agent ponatinib or imatinib after the cycle 20 phase of the trial. The last date of follow-up for this analysis was August 12, 2022. Patients received ponatinib, 30 mg/d, or imatinib, 600 mg/d, with reduced-intensity chemotherapy, followed by single-agent ponatinib or imatinib after cycle 20. The ponatinib dose was reduced to 15 mg on achievement of minimal residual disease-(MRD) negative complete remission. The primary end point of this interim analysis was MRD-negative complete remission (≤0.01% BCR::ABL1 [MR4] centrally assessed by reverse transcriptase-quantitative polymerase chain reaction), with complete remission maintained for at least 4 weeks at the end of cycle 3. The key secondary end point was event-free survival. Of 245 patients randomized (median age, 54 years; 133 [54.3%] female), 232 (ponatinib, n = 154; imatinib, n = 78) who had p190 or p210 dominant isoforms verified by the central laboratory were analyzed for the primary end point. The MRD-negative complete remission rate (primary end point) was significantly higher with ponatinib (34.4% [53/154]) vs imatinib (16.7% [13/78]) (risk difference, 0.18 [95% CI, 0.06-0.29]; P = .002). At the data cutoff, event-free survival had not met the prespecified number of events. Median event-free survival was not reached in the ponatinib group and was 29 months in the imatinib group. The most common adverse events were similar between treatment groups. Arterial occlusive events were infrequent and comparable between groups (ponatinib, 2.5%; imatinib, 1.2%). Ponatinib demonstrated a superior rate of MRD-negative complete remission at the end of induction vs imatinib when combined with reduced-intensity chemotherapy in adults with newly diagnosed Ph+ ALL. The safety profile of ponatinib was comparable with imatinib. ClinicalTrials.gov Identifier: NCT03589326.

Minimal residual disease monitoring in childhood Philadelphia chromosome-positive acute lymphoblastic leukemia: prognostic significance and correlation between multiparameter flow cytometry and real-time quantitative polymerase chain reaction

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CAR-T Therapy Followed by Hematopoietic Stem Cell Transplantation Can Improve Survival in Children Relapsed/Refractory Philadelphia Chromosome-positive B-cell Acute Lymphoblastic Leukemia.

Philadelphia chromosome (Ph)-positive B-cell acute lymphoblastic leukemia (ALL) has a high complete remission (CR) rate, but relapse and prolonged measurable residual disease remain serious problems. We sought to describe the CR rate measurable residual disease negative rate and address the results and safety of pediatric patients who underwent after receiving chimeric antigen receptor (CAR) specific for CD19 (CAR-19) followed by hematopoietic stem cell transplantation (HSCT) for the treatment of Ph-positive ALL. A descriptive study was conducted at Peking University People's Hospital from September 2013 to January 2021. 13 patients with relapsed/refractory Ph-positive B-ALL who received CAR-T therapy followed by allo-HSCT were included. We concentrated on the overall patient survival and CR rate. The median time between CAR-T therapy and allo-HSCT was 58 days. Among all the patients, the CR rate was 100%, the flow cytometry negativity rate was 84.62%, and the BCR-ABL negativity rate was 53.85% at 1 month after CAR-T infusion. All the patients achieved a major molecular response in 6 months after HSCT. After a median follow-up of 45 months, the 3-year OS rate was 66.7%, and the 3-year DFS rate was 61.5%. The 3-year OS rate of patients with BCR-ABL-positive pre-HSCT was significantly lower than that in the BCR-ABL-negative group (40.0% vs. 85.7%, P=0.042). Also, the same trend was observed for the 3-year DFS rate but did not differ significantly (40.0% vs. 75.0%, P=0.233). CAR-T therapy followed by allo-HSCT can be a safe and effective treatment for Ph-positive B-ALL pediatric patients.

Frontline combination of dasatinib and low-intensity chemotherapy in adults with de novo Philadelphia chromosome-positive acute lymphoblastic leukemia

ABSTRACT Background Studies on dasatinib-based low-intensity induction regimens and post-remission strategies are limited in China. Therefore, we conducted a single-center phase 2 trial in newly diagnosed adult patients with Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) to establish the efficacy and safety of this treatment approach. Research design and methods Patients received one month of dasatinib plus low-intensity chemotherapy and two months of dasatinib monotherapy for induction, followed by a single course of high-dose methotrexate for consolidation. Subsequently, they underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) or tyrosine kinase inhibitor (TKI)-based treatment for maintenance therapy between October 2015 and August 2022. Results Twenty-two patients were enrolled. Median age was 45 years (range, 20–71). The rates of major and complete molecular responses in the third month were 18.2% and 40.9% respectively. With a median follow-up of 15 months (range, 5–89), the estimated 3-year disease-free survival (DFS) and overall survival (OS) were 52.4% and 73.2%, respectively. The TKI-based cohort had a significantly poorer DFS (p = 0.014) and OS (p = 0.008) than the allo-HSCT cohort. Conclusions Our results suggest that dasatinib-based low-intensity chemotherapy is safe and effective as an induction strategy in the Chinese population. Allo-HSCT plays a crucial role in the long-term outcomes of patients with Ph+ ALL. Clinical trial registration The trial was registered at ClinicalTrials.gov as NCT02690922.

Involvement of BCR::ABL1 in laminin adhesion of Philadelphia chromosome-positive acute lymphoblastic leukemia through upregulation of integrin α6.

Adhesion of cancer cells to extracellular matrix laminin through the integrin superfamily reportedly induces drug resistance. Heterodimers of integrin α6 (CD49f) with integrin β1 (CD29) or β4 (CD104) are major functional receptors for laminin. Higher CD49f expression is reportedly associated with a poorer response to induction therapy in childhood B-cell precursor acute lymphoblastic leukemia (BCP-ALL). Moreover, a xenograft mouse model transplanted with primary BCP-ALL cells revealed that neutralized antibody against CD49f improved survival after chemotherapy. Considering the poor outcomes in Philadelphia chromosome (Ph)-positive ALL treated with conventional chemotherapy without tyrosine kinase inhibitors, we sought to investigate an involvement of the laminin adhesion. Ph-positive ALL cell lines expressed the highest levels of CD49f among the BCP-ALL cell lines with representative translocations, while CD29 and CD104 were ubiquitously expressed in BCP-ALL cell lines. The association of Ph-positive ALL with high levels of CD49f gene expression was also confirmed in two databases of childhood ALL cohorts. Ph-positive ALL cell lines attached to laminin and their laminin-binding properties were disrupted by blocking antibodies against CD49f and CD29 but not CD104. The cell surface expression of CD49f, but not CD29 and CD104, was downregulated by imatinib treatment in Ph-positive ALL cell lines, but not in their T315I-acquired sublines. Consistently, the laminin-binding properties were disrupted by the imatinib pre-treatment in the Ph-positive ALL cell line, but not in its T315I-acquired subline. BCR::ABL1 plays an essential role in the laminin adhesion of Ph-positive ALL cells through upregulation of CD49f.

Ponalfil trial for adults with Philadelphia chromosome-positive acute lymphoblastic leukemia: Long-term results.

Ponalfil trial for adults with Philadelphia chromosome-positive acute lymphoblastic leukemia: Long-term results.

Ponatinib-Related Vasospastic Angina.

Tyrosine kinase inhibitors (TKIs) are essential drugs for chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. Cardiovascular or arteriothrombotic adverse events have been reported in patients treated with TKIs. We report 3 cases of Ponatinib-related vasospastic angina, in which prophylactic administration of nitrates or calcium channel blockers was effective.

A Case of Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia with Coexistence of JAK2 V617F Clone.

A Case of Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia with Coexistence of JAK2 V617F Clone.

Allogeneic stem cell transplantation is still a highly curative therapy in adults with philadelphia chromosome-positive acute lymphoblastic leukaemia.

The application of tyrosine kinase inhibitors (TKIs) and novel immunotherapies has improved outcomes in patients with Ph + acute lymphoblastic leukaemia (ALL), and the issue of whether there is still a need for stem cell transplantation has become controversial. We performed a retrospective study to explore whether stem cell transplantation still held a place in patients with Ph + ALL if only imatinib and 2nd generation TKIs are available and affordable. A total of 292 patients were included. The median age was 38 years [range 14-64, IQR 28-48]. Patients receiving transplants (n = 216) had better rates of 4-year disease-free survival (DFS, 68% vs. 24%, P < .0001) and overall survival (OS, 72% vs. 47%, P < .0001) than those receiving continuous TKIs plus chemotherapy (TKI-chemo) (n = 76). In the multivariate analysis, male sex, WBC count ≥ 95 × 109/L and PLT count ≤ 154 × 109/L at diagnosis were significantly associated with poorer outcomes, and transplantation was significantly associated with favourable DFS and OS. In addition, the transplant outcomes were superior in any subgroup according to the number of risk variables. Furthermore, propensity score matching (PSM) analyses showed similar findings in the whole cohort and in age- and BCR-ABL1 level-based subgroups after the first or second consolidation. In conclusion, transplantation as a one-time procedure for adults with Ph + ALL patients remains important in countries lacking accessibility to third-generation TKIs or immunotherapies, regardless of the depth of the molecular response.

Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia in Children: A Retrospective Cohort Study at a Pediatric Oncology Center.

Background and objective Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL Ph+) is quite rare among pediatric patients. Its management has undergone significant changes in the past few years, leading to some variability in how it is approached. At the Portuguese Oncology Institute of Porto (IPOP),a tertiary oncological center, the standard of carehas been aligned with the guidelines proposed by the European intergroup study of post-induction treatment of ALL Ph+ (EsPhALL). In this study, we aimed to examine the experience and outcomes related tothe treatment of pediatric patients with ALL Ph+ at IPOP. Methods This retrospective cohort study involvedpediatric patients diagnosed with ALL Ph+ at IPOP between January 2008 and December 2022 and analyzed their outcomes. Results A total of 14 patients were included. IKFZ1 was altered in five patients (out of nine in whom it was searched). Five patients were treated according to EsPhALL 2004, which involved starting imatinib later in a discontinuous manner [resulting in both five-year overall survival (OS) and progression-free survival (PFS) of 60%]. The EsPhALL 2010 (preconizing a continuous imatinib regimen instead) was employed in three patients, with a five-year OS and PFS of 66.7%. Allchildren mentioned above received cranial irradiationtherapy (CRT). Finally, six were treated according to the EsPhALL 2015, which stopped including CRT in its backbone. The five-year OS was 100%, whereas every patient progressed with an increase in BCR::ABL1 levels greater than 1-log. Moreover, until 2015, all patients had been recommended to undergo allogeneic hematopoietic stem cell transplantation (alloHSCT). However, since 2015, alloHSCT has been exclusively reserved for relapsed/refractory (R/R) disease or poor responders with positive measurable residual disease (MRD). In total, alloHSCT was performed in nine patients. Conclusions Although initially associated with a poor prognosis, the ALL Ph+ paradigm is drastically shifting. Further studies will hopefully clarify the outcomes in this population and help understand the role of central nervous system (CNS) prophylaxis, alloHSCT, and MRD quantification.

Utility of allogeneic stem cell transplantation for adult Ph+ALL with complete molecular remission.

This study aimed to investigate the usefulness of allogeneic stem cell transplantation (allo-SCT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) in the first complete remission (CR1) with complete molecular remission (CMR). We compared the outcomes between Ph+ALL patients who did or did not undergo allo-SCT in CR1. We included patients enrolled in the prospective clinical studies in the tyrosine kinase inhibitor era conducted by the Japan Adult Leukemia Study Group, who achieved CMR within 3 months. A total of 147 patients (allo-SCT: 101; non-SCT: 46) were eligible for this analysis. In the multivariate analyses, allo-SCT was significantly associated with both superior overall survival (OS) (adjusted hazard ratio (aHR): 0.54; 95% CI: 0.30-0.97; p = .04) and relapse-free survival (RFS) (aHR: 0.21; 95% CI: 0.12-0.38; p < .001). The 5-year adjusted OS and RFS were 73% and 70% in the allo-SCT cohort, whereas they were 50% and 20% in the non-SCT cohort. Despite the higher non-relapse mortality (aHR: 3.49; 95% CI: 1.17-10.4; p = .03), allo-SCT was significantly associated with a lower relapse rate (aHR: 0.10; 95% CI: 0.05-0.20; p < .001). In addition, allo-SCT was also associated with superior graft-versus-host disease-free, relapse-free survival (aHR: 0.43; 95% CI: 0.25-0.74; p = .002). Propensity score-matched analyses confirmed the results of the multivariate analyses. In patients who achieved CMR within 3 months, allo-SCT in CR1 had superior survival and lower relapse compared with the non-SCT cohort.

Targeting IL-17A enhances imatinib efficacy in Philadelphia chromosome-positive B-cell acute lymphoblastic leukemia

Dysregulated hematopoietic niches remodeled by leukemia cells lead to imbalances in immunological mediators that support leukemogenesis and drug resistance. Targeting immune niches may ameliorate disease progression and tyrosine kinase inhibitor (TKI) resistance in Philadelphia chromosome-positive B-ALL (Ph+ B-ALL). Here, we show that T helper type 17 (Th17) cells and IL-17A expression are distinctively elevated in Ph+ B-ALL patients. IL-17A promotes the progression of Ph+ B-ALL. Mechanistically, IL-17A activates BCR-ABL, IL6/JAK/STAT3, and NF-kB signalling pathways in Ph+ B-ALL cells, resulting in robust cell proliferation and survival. In addition, IL-17A-activated Ph+ B-ALL cells secrete the chemokine CXCL16, which in turn promotes Th17 differentiation, attracts Th17 cells and forms a positive feedback loop supporting leukemia progression. These data demonstrate an involvement of Th17 cells in Ph+ B-ALL progression and suggest potential therapeutic options for Ph+ B-ALL with Th17-enriched niches.

Philadelphia chromosome-positive acute lymphoblastic leukemia presenting with bilateral serous retinal detachment: A case report and review of the literature

We report a case who presented with bilateral serous retinal detachment (SRD) as the initial sign of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ ALL). A 49-year-old female presented with blurred vision. A colored fundus image of the patient revealed SRD around the posterior pole’s optic disc. Bone marrow aspiration showed infiltration with lymphoblasts. The patient was diagnosed with Ph+ ALL. SRD regressed in the color fundus image of the patient after induction chemotherapy and intrathecal methotrexate. The patient’s visual symptoms completely regressed. In conclusion, acute leukemia should be considered in the differential diagnosis of cases presenting with SRD.

Ponatinib Improved the Prognosis of Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: A Japanese Single-Center Cohort Study.

Introduction The overall survival (OS) of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL) has improved with the combination of tyrosine kinase inhibitor (TKI) with intensive chemotherapy. In recent years, there has been increased interest in the possibility of long-term survival without allogeneic hematopoietic stem cell transplantation (HSCT) or maintenance therapy. The aim of this study was to determine the effectiveness of treatment and the resultant outcomes in Ph+ALL patients using real-world data. Methods We performed a single-center retrospective analysis utilizing Akita University Hospital data (Akita, Japan) from November 2000 to June 2023 to evaluatethe outcomes of TKI with intensive chemotherapy for Ph+ALL. Results Twenty-three patients with Ph+ALL were treated with intensive chemotherapy combined with TKI, including six imatinib, four dasatinib, and 13 ponatinib. The median patient age was 53 years (range; 28-67). Eighteen patients (78%) achieved complete molecular remission (CMR) within three months. HSCT was performed in 16 patients (70%), all of whom did not receive post-transplant TKI maintenance therapy. Six of the seven patients who did not undergo HSCT received maintenance therapy with ponatinib after intensive chemotherapy. The three-year OSwas 81%. Ponatinib treatment resulted in a much higher OS rate than imatinib/dasatinib (100% vs. 60%;P=0.011). CMR within three months was identified as a prognostic factor for molecular relapse-free survival (hazard ratio (HR)=0.22;P=0.027). CD20 positivity was identified as a risk factor for hematological relapse (HR=5.2, P=0.032). Conclusion Even in a single-center cohort study, ponatinib, as a combination TKI with intensive chemotherapy or maintenance therapy, may improve the prognosis of Ph+ALL. Patients with CMR within three months might not necessarily needto receive HSCT, but a subsequent treatment-free status could have been achieved only by HSCT. Furthermore, CD20 positivity may be a useful biomarker for future treatment decisions in patients with Ph+ALL.

Olverembatinib Combined with Venetoclax and Reduced-Intensity Chemotherapy for Patients with Newly Diagnosed Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: Early Results from a Phase II Study

Background The combination of olverembatinib (HQP1351), a novel third-generation tyrosine kinase inhibitors (TKIs), with venetoclax generated high response rates in patients with relapsed/refractory Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph + ALL). However, the efficacy and safety of these two agents-based regimens as frontline treatment remains unknown. Methods This is a single-arm phase II study (NCT05594784) that enrolled patients (pts) ≥ 14 years (yrs) of age with newly diagnosed Ph + ALL. Pts were required to have an ECOG performance score ≤ 2 and adequate organ function. Pts with accelerated phase or blastic phase of chronic myeloid leukemia were excluded. Pts were treated with a combination of venetoclax (100 mg d1, 200 mg d2, 400 mg d3-28), olverembatinib 40 mg once every continuously other day, vincristine 1.4 mg/m 2 (maximum dose 2 mg) on day 1, 8, 15, 22, and prednisone 60 mg/m 2 on day 1-14; 40 mg/m 2 on day 15-28 in cycle 1. In cycle 2-3, oral treatment with venetoclax 400 mg × 7 days, olverembatinib once every other day continuously and prednisone 60 mg/m 2 × 7 days was administrated in the form of outpatient treatment (Figure 1A). Cycles were repeated every 28 days. Olverembatinib 40 mg once every other day was given during cycle 1 and was reduced to 30 mg once every other day for pts achieving a complete molecular response (CMR). Routine triple intrathecal injection (methotrexate 10 mg, cytarabine 50 mg, and dexamethasone 10 mg) was performed to prevent central nervous system involvement. The selection of subsequent treatment was determined based on the patient's molecular response at 3 months and the availability of donor. The primary end point of this study was the CMR rate at 3 months. CMR was defined as undetectable BCR:ABL1 transcripts by using RT-PCR method with sensitivity of 0.001%. Major molecular response (MMR) was defined as more than 3-log reduction of BCR:ABL1 transcripts. Results From August 2022 to April 2023, a total of 31 pts were enrolled. All pts completed 3 cycles of treatment and could be assessed for the primary end point. Th data cutoff date was 25 th July 2023 with a median follow-up time of 5.8 months. The median age was 40 years (range, 20-66 years) and males accounted for 58.1%. Twenty-three pts (74.2%) expressed the p190 transcript and 8 pts (25.8%) expressed the p210 transcript. The median expression level of BCR:ABL1 was 96.33% (range, 70.79%-175.39%). All patients achieved CR at the end of cycle 1 and no tumor lysis syndrome or treatment-related deaths occurred. Molecular response at the end of cycle 1 was CMR in 17 patients (54.8%), MMR in 8 (25.8%), and less than MMR in 6 (19.4%). Molecular response at 3 months was CMR in 19 patients (61.3%), MMR in 10 (32.3%), and less than MMR in 2 (6.5%) (Figure 1B). Of the 10 pts with MMR at 3 months, 8 pts had BCR:ABL1 transcript levels fluctuating between 0.001% and 0.01%. No patients developed relapses or deaths at the last follow-up. The regimen was well-tolerated and safe. Most side effects were grade 1-2. The demand for transfusion and the incidence of infections significantly decreased compared to our historic data treating with intensive chemotherapy plus TKIs. No patient discontinued olverembatinib or venetoclax due to toxicity. Conclusion The combination of olverembatinib and venetoclax with reduced-intensity chemotherapy is a safe and effective regimen in patients with newly diagnosed Ph + ALL. The regimen results in high rates of CMR in the absence of intensive chemotherapy or immunotherapy.

Olverembatinib (HQP1351) Combined with Chemotherapy Is an Effective and Safe Treatment in Patients with Philadelphia Chromosome-Positive (Ph +) Acute Lymphoblastic Leukemia (ALL) and Chronic Myeloid Leukemia in Lymphoid Blast Phase (CML-LBP) That Failed TKI-Based Regimens

Background The prognosis of relapsed or refractory (R/R) Philadelphia Chromosome-Positive (Ph+) acute lymphoblastic leukemia (ALL) and TKI-resistant chronic myeloid leukemia in lymphoid blast phase (CML-LBP) remains poor, with lower rates of complete remission (CR) and shorter durations of response. Olverembatinib is a novel third-generation tyrosine kinase inhibitor (TKI) that has been demonstrated to effectively target a wide range of BCR::ABL1 kinase mutations, especially T315I, in patients with CML in the chronic or accelerated phase resistant to either imatinib or second-generation TKIs. However, data on olverembatinib-based regimens in R/R Ph+ ALL and CML-LBP are limited. Here, we report the efficacy and safety of olverembatinib, combined with chemotherapy, in patients with Ph+ ALL or CML-LBP that failed prior TKI-based therapies. Methods A retrospective study was conducted in adults with Ph + ALL or CML-LBP who failed imatinib- or second-generation TKI-based chemotherapy and subsequently received olverembatinib-based chemotherapy. Per NCCN 2023 guidelines: refractory disease was defined as CR not achieved at the end of induction; relapsed disease, reappearance of blasts in the blood or bone marrow (&amp;gt; 5%) or any extramedullary site after CR; molecular resistance, persistent or rising BCR::ABL1 transcript (&amp;gt; 1-log) by real-time quantitative polymerase chain reaction (RT-qPCR); and complete molecular response (CMR), BCR::ABL1 transcript &amp;lt; 0.01% by RT-qPCR. The primary endpoints of this study were CR rates in R/R patients and CMR rates in molecular-resistant patients. Results From February 2022 to May 2023, 31 patients were included in this study, including 24 (77%) with TKI-based chemotherapy-failed Ph + ALL; 7 (23%) with TKI-resistant CML-LBP; 15 (48%) with R/R disease; and 16 (52%) with molecular-resistant disease. A total of 17 (57%) patients were male, and the median (range; IQR) age was 46 (20-72; 30-64) years. Among 30 patients screened for BCR::ABL1 kinase domain mutations before administration of olverembatinib, 6 (19%) had no mutations; 15 (48%) had T315I; and 9 (29%) had other mutations, including E255K (n = 2), G250E(n = 2), D241E (n = 1), Y253H (n = 1), F317L (n = 1), F359C(n = 1), and Y253Fplus M351T (n = 1). The 15 R/R patients (11, Ph + ALL; 4, CML-BP) received olverembatinib 30 or 40 mg on alternate days combined with VP (vindesine 4 mg once per week for 4 weeks and prednisone 1 mg/kg for 3 weeks and tapered at the fourth). A total of 13 (86%) patients achieved CR after 4-week induction therapy. At a median (IQR) follow-up of 8 (4-13) months, 5 patients received allogeneic transplantation in CR, and were alive in CMR. A total of 8 patients received olverembatinib-based consolidation chemotherapy of either VP (n = 4) or hyper-CVAD (n = 4) after achieving CR. Six patients relapsed, of whom 4 died, and 1 remained in CMR. The 1-year relapse-free survival (RFS) and 1-year survival rates were 52% (95% CI, 21-83) and 68% (95% CI, 37-98), respectively. Among the 16 patients with molecular resistance to TKI-based chemotherapy (imatinib [n = 4]; dasatinib [n = 9]; flumatinib [n = 3]), 2 received olverembatinib monotherapy, 7 olverembatinib plus VP, and 7 hyper-CVAD, of whom 8 received subsequent allogeneic transplantation. At a median (IQR) follow-up of 9 (5-11) months, 1 of the patients receiving olverembatinib monotherapy progressed to hematologic relapse and was switched to CAR T-cell therapy; the other patient did not achieve CMR and underwent transplantation. Of the 14 patients receiving olverembatinib plus chemotherapy, 7 (50%) achieved CMR and 3 (21.4%) progressed to relapse, of whom 1 had hematological relapse and 2 developed central nervous system leukemia (CNSL) with bone marrow remission. A total of 7 patients received allogeneic transplantation, of whom 3 achieved and 4 did not achieve CMR before transplantation. After transplantation, all the 7 patients were in CMR except one who developed CNSL. The 1-year RFS and survival rates were 67% (95% CI, 42-91) and 93% (95% CI, 79-100), respectively. Among all patients, hematologic adverse events were readily manageable. Treatment-related nonhematologic severe adverse events were observed in 3 patients, including (each) stable angina pectoris, severe pneumonia, and fatal Klebsiella sepsis. Conclusions Olverembatinib-based chemotherapy is effective and safe in patients with R/R and molecular resistant Ph + ALL or CML-LBP.

Chemotherapy-Free Combination of Blinatumomab and Ponatinib in Adults with Newly Diagnosed Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: Updates from a Phase II Trial

Background Blinatumomab and ponatinib demonstrated efficacy in patients with Philadelphia chromosome (Ph)-positive acute lymphoblastic leukemia (ALL). A chemotherapy-free regimen combining both drugs in the frontline setting may mitigate the risk of toxicities and the need for hematopoietic stem cell transplantation (HSCT). Methods In this phase II trial, patients ≥18 years of age with newly diagnosed Ph-positive ALL were eligible. They were required to have a performance status of ≤2, total bilirubin ≤2x the upper limit of normal (ULN), and ALT/AST ≤3x the ULN. Patients with uncontrolled cardiovascular disease or clinically significant central nervous system (CNS) comorbidities (except for CNS leukemia) were excluded. Patients received up to 5 cycles of blinatumomab in combination with ponatinib, followed by ponatinib maintenance for ≥5 years. Ponatinib 30mg daily was given during Cycle 1 and decreased to 15mg daily once a complete molecular response (CMR) was achieved. Patients also received 12 doses of prophylactic intrathecal (IT) chemotherapy with alternating cytarabine and methotrexate. The primary endpoint was the CMR rate. Secondary endpoints included response rates, safety measures, event-free survival (EFS), and overall survival (OS). Results Between June 2018 and May 2023, 62 pts with newly diagnosed Ph-positive ALL were treated. Baseline characteristics are shown in Table 1. Twenty-two patients were in complete remission (CR) at the start of therapy. Among 40 patients evaluable for hematologic response, 39 (98%) achieved CR/CRi; 1 patient had early death. Among 55 patients evaluable for molecular response, 37 (67%) achieved CMR after 1 cycle, and 46 (84%) achieved CMR at any time. Forty-seven patients were evaluated for measurable residual disease (MRD) by next-generation sequencing at a sensitivity level of 10 -6, of whom 43 (91%) were found to have negative MRD. Five of these patients with undetectable MRD by NGS had low-level BCR:ABL1 transcripts detected by PCR at the same time (ranging from 0.01% to 1.23% IS). Four of them had p190 transcript and one had p210. The median follow-up was 17 months (range, 2-61 months). Six patients (10%) relapsed after a median of 21 months of remission (range, 8-24 months): two relapsed in the bone marrow (one with acquired E225V mutation), one had an extramedullary-only relapse (Ph-negative and MYC-rearranged relapse), and three had a CNS-only relapse (after 20, 22, and 23 months). Four patients died (one from intracranial hemorrhage, one from post-procedural hemorrhage, one from brain aneurysm, and one following CNS relapse with intracranial edema and septic shock). One leukemia-related death occurred on study; the estimated 2-year EFS and OS rates were 77% and 89%, respectively (Figure 1). Only one patient underwent HSCT in first CR due to persistently low-level BCR:ABL1 positivity. Among the 52 patients in ongoing remission without HSCT, the median duration of response was 16 months (range, 2-61). Most adverse events were grade 1-2 and were consistent with the known toxicity profile of the two agents. Ponatinib was discontinued in two patients due to possibly related adverse events (cerebrovascular accident and coronary artery stenosis in one patient each). Conclusions The chemotherapy-free combination of blinatumomab and ponatinib is safe and effective in newly diagnosed Ph-positive ALL, with high rates of MRD negativity. Encouraging duration of remission and OS has been observed without the need for HSCT.

Chemotherapy-Sparing Induction Followed By Consolidation and Maintenance with Blinatumomab and Concurrent Oral Tyrosine Kinase Inhibitor Therapy for Newly-Diagnosed Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia: Primary Endpoint Results from the Blissphall Study

Background: Oral ABL-targeted kinase inhibitors (TKIs) have transformed treatment of BCR::ABL+ (Philadelphia chromosome-positive, Ph+) acute lymphoblastic leukemia (ALL). Induction (IND) w/ corticosteroids (CS) and dasatinib (DAS) alone results in morphologic complete response (mCR) rates approaching 100% but low rates of measurable residual disease (MRD) negativity; addition of intensive chemotherapy to TKIs adds risks of myelosuppression. DAS + the CD3/CD19 bispecific T-cell engager blinatumomab (BLIN) is effective consolidation (CONSOL) for Ph+ ALL, though ABL kinase mutations conferring resistance can arise early in therapy (Foà, NEJM, 2020). We designed a phase II study of BLIN as part of a chemotherapy sparing strategy in pts w/ Ph+ ALL (BLISSPHALL), introducing BLIN as early as 6 weeks into treatment for pts in mCR, w/ aim of expediting MRD clearance and suppressing resistant clones early in disease course, and including a maintenance (MAINT) phase of BLIN + TKI for pts in molecular response. Methods: We conducted a multicenter trial of TKI + CS IND and TKI + BLIN CONSOL + MAINT in adults (≥18 yrs) w/ newly-diagnosed (ND) Ph+ ALL (NCT04329325). Study schema is depicted in Figure 1. Pts received CS pre-phase w/ prednisone (PRED) or dexamethasone (DEX) followed by modified GIMEMA LAL1205 IND (DEX + DAS 140 mg/d w/ DAS dose adjustments or TKI change per protocol) w/ intrathecal methotrexate (IT MTX) d22, 43 and bone marrow (BM) MRD assessments including FACS and BCR::ABL1 PCR. Pts in mCR on d43 could proceed to CONSOL w/ 3 cycles (C) of TKI + BLIN 28 mcg/d IVCI, d1-28, w/ 14d off BLIN between cycles and BM MRD assessment/IT MTX after each cycle. TKI was given continuously including between BLIN cycles. Pts in protocol-defined complete molecular response (CMR; MRD negative by FACS and no detectable BCR::ABL1 transcripts) after CONSOL could proceed to MAINT (C4-7 BLIN + TKI, 28d off between cycles). The primary objective is to determine the proportion of evaluable pts achieving CMR by the end of CONSOL (≤ 3C BLIN + TKI). Secondary objectives include safety/toxicity of BLIN + DAS, duration of CMR, incidence of relapse, event-free/overall survival. Toxicities were defined by CTCAE v5.0. Results: 17 pts enrolled (12 women, 5 men) w/ median age 50 yrs (range 22-87); BCR::ABL1 transcript type p190 (n=15) or p210 (n=2). Median follow-up 11.7 months (range 3-24). All began DAS 140 mg/d as initial TKI; 4 changed TKI for DAS intolerance per protocol (bosutinib, n=2; ponatinib [PON], n=2) and remained on study; TKI was changed to PON in 1 other pt to optimize BCR::ABL1 transcript suppression pre-allogeneic transplant (alloHCT) and that pt was withdrawn from study. Two had interruption or delay of BLIN due to toxicity (grade [G] 3 transaminase elevation, n=1; G2 cytokine release syndrome, n=1); BLIN was resumed in both. Figure 2 lists nonhematologic adverse effects (AEs) seen in ≥2 pts at least possibly related to TKI or BLIN while on study. One pt developed G3 pancreatitis after DAS was changed to PON; TKI was changed back to DAS. There were no G4-5 AEs. All pts (100%) achieved mCR during IND (median d22). Ten achieved CMR to date (5 during IND, 5 during CONSOL) and 6 did not achieve CMR; determination pending in 1 pt. By FACS, 16/17 achieved BM MRD negativity; 13/14 evaluable pts had no evidence of malignant clonal IgH rearrangement (IgHR) by next generation sequencing (NGS). Notably, 3 pts w/ persistent low-level BCR::ABL1 transcripts had no evidence of malignant clonal IgHR by NGS but were withdrawn post-CONSOL as protocol required BCR::ABL1 PCR negativity to proceed to MAINT. Two pts relapsed, both after achieving CMR (one declined CONSOL and self-discontinued TKI; one had extramedullary (EM) relapse w/ ABL T315I mutation). Four pts underwent alloHCT in CR1 (rising MRD levels on study leading to change in therapy, n=1; persistent BCR::ABL1 PCR positivity, n=2; IKZF1 plus phenotype, n=1); one underwent alloHCT in CR2 following EM relapse. Conclusions: DAS + CS IND w/ addition of BLIN to TKI in mCR leads to high rates of deep molecular response w/ low risk of early relapse and low rates of severe regimen-related toxicity in pts w/ ND Ph+ ALL. Use of PON (vs DAS) as initial TKI w/ BLIN may further suppress resistant clones. Further f/u is needed to confirm durability of CMR w/ BLIN + TKI CONSOL ± MAINT in absence of alloHCT and whether pts w/ persistent BCR::ABL1 PCR positivity and no malignant clonal IgHR by NGS exhibit similar outcomes to those in CMR.

Combination of Olverembatinib and VP Regimen As First-Line Therapy for Adult Patients with Philadelphia Chromosome-Positive Acute Lymphoblastic Leukemia

Backgrand ： Ph+ALL is the largest genetically defined subtype in adult ALL and is considered associated with high relapse risk and inferior clinical outcomes. The combination of tyrosine kinase inhibitors (TKI) with intensive chemotherapy has achieved a major step forward in the therapy of Ph+ALL in deep response and long-term survival. The upfront use of third generation TKI ponatinib has improved the frequency of complete molecular response (CMR) and the overall survival rate to a greater extent. More interesting, the data coming from MDACC showed that combination of ponatinib in the chemotherapy in Ph+ALL maybe challenge the need for stem cell transplantation (SCT) in most patients who achieved CMR (defined BCR-ABL1 transcript &amp;lt; 0·01%) within 3 months after induction therapy. But the cardiovascular adverse event(AE) of ponatinib was more and severely frequently occurred in the former reports. Olverembatinib,a new third generation of TKI, which can also suppress the mutation of T315I and showed promising results in the Ph+CML. Herein we designed the clinical trial to invest the efficiency and safety of Olverembatinib combine with VP regimen (OVP) on Ph+ALL patients as the first-line therapy. Motheds: In this multi-centers, phase 2, single-arm trial, adult patients with previously untreated Ph+ALL were sequentially enrolled. The patients had to be aged 18 years or older, have normal cardiac function (defined by ejection fraction above 50%), and have adequate organ function (serum creatinine≦3*ULN，BUN≦3*ULN，ALT≦3*ULN，AST≦3*ULN，serum bilirubin≦3*ULN). They received three cycles of OVP regimen(for 28 days each cycle :olverembatinib 40mg qod d1-28，Vindesine 4mg d1,8,15,22,Prednisone1mg/Kg/d d1-21,0.5mg/kg/dd22-28). Twelve intrathecal injections of cytarabine alternating with methotrexate were designed as central nervous system prophylaxis in the following therapy after the diagnosis. Findings: 32 patients were screened and 29 were eligible from June 21, 2022 until 21 July,2023. 3 Patients were withdrawn from the clinical trial(1 refused therapy after induction,1 early death due to Covid infection, 1 Protocol deviation ).Among all , Male 12 and Female 17. BCR/ABL1 transcript:M-p210 (11),m-p190（18）.The Median Age was 45(19-74) years old. The Median WBC was 24.8(1.06-308.00) *10E9/L. The treatment has resulted in a 100% overall response, including 96% (24/25) CR and 4% (1/25) CRp. As of data collection,23 finished 3cycles of OVP chemotherapy and 82.6% (19/23) got CMR.AS far the rest 6 patients, 1 got CMR after 1 cycle OVP,1 got CMR after 2cycles of OVP, the other 4 patients were undergoing induction therapy. The total CMR rate was 84% (21/25) at any time. The CMR rate was 36%（9/25） ,76%（19/25）and 82.6%(19/23) at 4weeks,8weeks and 12 weeks respectively. Among all the patients finished the 3 cycles, there were 4 patients not reached the CMR and all of them were M-bcr/abl-p210 protein status. The best response was MMR for 3 patients and CR for 1patient. The CMR rate was 70% (7/10) in M-bcr/abl-p210 transcript and 100% (13/13) in that of m-bcr/abl-p190. During a median follow-up of 241 days, one patient died within one month after transplantation, while all the remaining survived without relapse. During induction therapy, 4 patients had platelets consistently above normal values and 4 patients did not experience a further decrease in hemoglobin compared to baseline. The median time for the occurrence of the lowest values of platelets, hemoglobin, and neutrophils was 6th, 12th, and 11th respectively. The most common non-Hematology AE was liver function damage. AE events greater than or equal to grade 3 included 2 cases of elevated Alanine transaminase ,3 cases γ- GT elevation and 2 cases of triglyceride elevation. Other AEs were mild and less than level 3. Discussion: Ongoing efforts exist to optimize therapeutic options in the frontline for Ph+ALL. The future lies in using less cytotoxic and more targeted agents. The first results of our ongoing trial indicate that the OVP regimen is effective in achieving early high rate of CMR in patients with newly diagnosed Ph+ALL as first-line therapy. All these results were achieved with surprisingly few toxic effects.Until now,16 patients underwent ASCT. Will the excellent outcomes be preserved with longer？ Will there be a difference in long-term outcomes between patients who underwent ASCT and those who do not?The trial is ongoing. we need more time to observe.