Reassessing the role of high dose cytarabine and mitoxantrone in relapsed/refractory acute myeloid leukemia.

A substantial segment of patients with acute myeloid leukemia (AML) will relapse following an initial response to induction therapy or will prove to be primary refractory. High-dose cytarabine and mitoxantrone (HiDAC/MITO) is an established salvage therapy for these patients. We studied all adult patients with relapsed/refractory (R/R) AML who were treated with HiDAC/MITO in our center between the years 2008-2017. To determine whether responding patients harbored a unique molecular signature, we performed targeted next-generation sequencing (NGS) on a subset of patients. The study cohort consisted of 172 patients with a median age of 54 years (range 18-77). The composite complete remission rate was 58%; 11 patients (6%) died during salvage therapy. Median survival was 11.4 months with a 1-year survival rate of 48%. In multivariate analysis favorable risk cytogenetics [Odds ratio (OR)=0.34, confidence interval (CI) 95%, 0.17-0.68; P = 0.002], and de-novo AML (OR = 0.4, CI 95%, 0.16-0.98; P = 0.047) were independently associated with a favorable response. Patients who attained a complete remission had a median survival of 43.7 months compared with 5.2 months for refractory patients (p < 0.0001). Neither the FLT3-ITD and NPM1 mutational status nor the indication for salvage therapy significantly impacted on the response to HiDAC/MITO salvage. NGS analysis identified 20 different mutations across the myeloid gene spectrum with a distinct TP53 signature detected in non-responding patients. HiDAC/MITO is an effective salvage regimen in R/R AML, however patients with adverse cytogenetics or secondary disease may not benefit as much from this approach.

Real-life Experience With Ponatinib in Chronic Myeloid Leukemia: A Multicenter Observational Study.

BACKGROUND: The strict recruitment criteria of patients for clinical trials often lead to reduced generalizability of the findings. We studied how ponatinib is used outside clinical trials in patients with chronic myeloid leukemia (CML). PATIENTS AND METHODS: The present retrospective study included all patients with a diagnosis of CML who had received ponatinib in 7 medical centers in Israel. RESULTS: From 2011 to 2016, we identified 37 patients with CML who had received ponatinib, 21 in the chronic phase and 16 in the advanced phase. Only 9 patients (26%) harbored the T315I (threonine to isoleucine mutation at position 315) mutation. All patients had received ≥ 1 previous tyrosine kinase inhibitor. The median age in our cohort was 43 years (range, 9-82 years), significantly younger than expected for patients with relapsed or refractory CML and 20 years younger than the median age of patients who participated in the PACE (ponatinib Philadelphia-positive acute lymphoblastic leukemia and CML evaluation) trial. During a median follow-up of 14 months (range, 1-51 months), the overall response rate was 85%. Of 34 patients, 16 (47%) experienced at least a major molecular response. Of the 37 total patients, another 16 patients (43%) discontinued treatment because of disease progression (n = 6), vascular complications (n = 1), severe cytopenia (n = 2), or for other reasons (n = 7). CONCLUSION: In real life, ponatinib is a "niche-drug" reserved for a unique population of exceptionally young patients with CML with or without the T315I mutation. In this highly selected group, very different from the PACE cohort, ponatinib achieved high overall response rates.

Immunological effects of nilotinib prophylaxis after allogeneic stem cell transplantation in patients with advanced chronic myeloid leukemia or philadelphia chromosome-positive acute lymphoblastic leukemia.

Allogeneic stem cell transplantation remains the standard treatment for resistant advanced chronic myeloid leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. Relapse is the major cause of treatment failure in both diseases. Post-allo-SCT administration of TKIs could potentially reduce relapse rates, but concerns regarding their effect on immune reconstitution have been raised. We aimed to assess immune functions of 12 advanced CML and Ph+ ALL patients who received post-allo-SCT nilotinib. Lymphocyte subpopulations and their functional activities including T-cell response to mitogens, NK cytotoxic activity and thymic function, determined by quantification of the T cell receptor (TCR) excision circles (TREC) and TCR repertoire, were evaluated at several time points, including pre-nilotib-post-allo-SCT, and up to 365 days on nilotinib treatment. NK cells were the first to recover post allo-SCT. Concomitant to nilotinib administration, total lymphocyte counts and subpopulations gradually increased. CD8 T cells were rapidly reconstituted and continued to increase until day 180 post SCT, while CD4 T cells counts were low until 180-270 days post nilotinib treatment. T-cell response to mitogenic stimulation was not inhibited by nilotinib administration. Thymic activity, measured by TREC copies and surface membrane expression of 24 different TCR Vß families, was evident in all patients at the end of follow-up after allo-SCT and nilotinib treatment. Finally, nilotinib did not inhibit NK cytotoxic activity. In conclusion, administration of nilotinib post allo-SCT, in attempt to reduce relapse rates or progression of Ph+ ALL and CML, did not jeopardize immune reconstitution or function following transplantation.

Sensitive Replicate Real-Time Quantitative PCR of BCR-ABL Shows Deep Molecular Responses in Long-Term Post-Allogeneic Stem Cell Transplantation Chronic Myeloid Leukemia Patients.

Real-time quantitative PCR (RT-qPCR) is commonly used for follow-up of chronic myeloid leukemia (CML) patients treated with tyrosine kinase inhibitors, but its current sensitivity does not allow detection of very low BCR-ABL levels. Therefore RT-qPCR negativity is not synonymous with complete molecular response. Replicate RT-qPCR had shown increased sensitivity in tyrosine kinase inhibitor-treated patients and was, therefore, used here to evaluate whether RT-qPCR-negative post-allogeneic stem cell transplantation (SCT) patients harbor detectable disease. Samples from 12 patients were tested at 2 time points using 82 replicates of BCR-ABL RT-qPCR. One patient (38 months after SCT) had detectable transcripts at baseline and none at the follow-up test, done at a median of 107 months after SCT. This suggests cure from CML in the majority of allogeneic SCT patients who have no transcripts detectable by replicate RT-qPCR for BCR-ABL.

Salvage therapy with ARA-C and gemtuzumab ozogamicin in AML patients relapsing after stem cell transplantation.

Acute myeloid leukemia (AML) relapse is often associated with a poor outcome, especially after allogeneic stem cell transplantation (Allo-SCT). In patients relapsing early after SCT treatment, options are further limited by the fear for increased toxicity. We report our experience with ARA-C and gemtuzumab ozogamicin (GO) combination in relapsed post-SCT AML patients. Therapy consisted of ARA-C (1 gr/m(2)) for 4 days followed by one dose of GO 9 mg/m(2) on day 5 and was supported by donor stem cells when possible. Responding patients not developing graft versus host disease (GVHD) were eligible for immunotherapy with donor lymphocyte infusion (DLI) or a second Allo-SCT. Sixteen patients, median age 53 years (range 31-63), are included in this analysis. Patients underwent SCT for high-risk AML (n = 11) or AML relapse (n = 5), and 81 % had an early post-SCT relapse. Responses were achieved in 60 % of evaluable patients (CR-5 CRp-4). Median probabilities of survival (OS) and event-free survival (EFS) in the entire cohort, responding and non-responding patients were 103 and 76 days, 183 and 97 days, and 79 and 16 days, respectively. At 1-year follow-up, 25 % of patients were alive; however, all had relapse. Treatment resulted in grade 3-4 neutropenia and thrombocytopenia in all patients, and 27 % each had grade 3-4 hyperbilirubinemia or elevation of liver enzymes. One patient died during treatment due to intracranial hemorrhage. Of the six patients proceeding to second SCT or receiving DLI, three patients developed mild veno-occlusive disease (VOD). Combination therapy with ARA-C and GO after SCT results in short-term disease control and limited toxicity and could be considered for patients who are candidates for further immunotherapy.

Phase 1/2 study of nilotinib prophylaxis after allogeneic stem cell transplantation in patients with advanced chronic myeloid leukemia or Philadelphia chromosome-positive acute lymphoblastic leukemia.

BACKGROUND: Allogeneic stem cell transplantation (SCT) remains the standard treatment for advanced chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL). Relapsed disease is the major cause of treatment failure, especially when SCT is given in the setting of advanced disease. Tyrosine kinase inhibitors can be given after transplantation prophylactically or after the detection of minimal residual disease (MRD) to reduce the relapse risk. METHODS: Posttransplant nilotinib was started after the achievement of sustained engraftment and the resolution of transplant-related toxicities. Nilotinib was continued until progression or unacceptable toxicity. RESULTS: Twenty-two patients with advanced CML (n = 15) or Ph(+) ALL (n = 7) underwent SCT with human leukocyte antigen-matched siblings (n = 11), unrelated donors (n = 7), or alternative donors (n = 4). Sixteen patients were given prophylactic nilotinib maintenance, which was started at a median of 38 days after transplantation. Six patients stopped the treatment because of toxicities (mostly gastrointestinal and hepatic). After nilotinib maintenance, 11 patients achieved (n = 9) or maintained (n = 2) a complete molecular response (CMR), and only 1 of them later relapsed. Four of the 5 patients not achieving CMR relapsed. At a median follow-up of 46 months, 9 patients were alive, and 13 had died. The 2-year overall and progression-free survival rates were 55% (95% confidence interval [CI], 34%-75%) and 45% (95% CI, 25%-66%), respectively. Among the 16 nilotinib recipients, the rates were 69% (95% CI, 46%-92%) and 56% (95% CI, 32%-81%), respectively. The 2-year nonrelapse mortality and relapse rates for all patients were 32% (95% CI, 17%-58%) and 23% (95% CI, 11%-49%), respectively. CONCLUSIONS: Nilotinib is relatively safe and effective prophylactic therapy for the prevention of relapse after SCT. It may control MRD and convert patients to CMR, which is associated with prolonged survival. These observations merit further study in larger scale studies.

The impact of R-VACOP-B and interim FDG-PET/CT on outcome in primary mediastinal large B cell lymphoma.

The choice of a rituximab-based regimen and the prognostic significance of interim 2-[fluorine-18]fluoro-2-deoxy-D-glucose-positron emission tomography/computed tomography (FDG-PET/CT) in primary mediastinal large B cell lymphoma (PMBCL) are debatable. We evaluated the clinical features and outcomes of 95 consecutive patients with PMBCL who were treated between 1985 and 2009. Forty-three patients received rituximab-based chemotherapy, R-VACOP-B (N = 30) or R-CHOP21 (N = 13), whereas 52 patients were treated with VACOP-B (N = 47) or CHOP21 (N = 5). Radiotherapy was not given. Patients who received rituximab had a 5-year progression-free survival (PFS) of 79 % and overall survival (OS) of 97 % compared with 58 % (p = 0.06) and 88 % (p = 0.2), respectively, without rituximab. Five-year PFS in patients treated with R-VACOP-B, R-CHOP21, VACOP-B, and CHOP21 were 83, 69, 62, and 20 %, respectively (p = 0.039). However, direct comparison showed that the difference between PFS rates in patients receiving R-VACOP-B compared to R-CHOP21 was not statistically significant (p = 0.3). None of the standard clinical risk factors predicted for PFS and OS in patients receiving rituximab (R)-chemotherapy. Mid-interim FDG-PET/CT scans were performed in 30/43 patients who received R-chemotherapy. The negative predictive values of mid-PET activity were high (100 % for R-VACOP-B and 86 % for R-CHOP21) while the positive predictive values (PPV) were relatively low (30 and 75 %, respectively). Despite the low PPV, the 5-year PFS for mid-PET-negative patients (N = 16) was significantly higher (94 %) than that for mid-PET-positive (N = 14) patients (57 %, p = 0.015). This retrospective analysis demonstrates that the superiority of VACOP-B over CHOP21 for treatment of PMBCL disappeared once rituximab was added. The potential benefit of using interim PET activity as a guide for continuing therapy in patients with PMBCL remains unclear due to the relatively low PPV.

Nilotinib-associated acute pancreatitis.

OBJECTIVE: To report a case of acute pancreatitis in a patient receiving nilotinib for chronic myelogenous leukemia (CML). CASE SUMMARY: A 69-year-old man recently diagnosed with chronic phase CML received nilotinib 300 mg twice daily and was admitted with acute pancreatitis that appeared the day after the first dose. The patient had normal levels of triglycerides and denied alcohol use. Serum pancreatic enzymes were within normal limits the day before nilotinib initiation. Abdominal computed tomography demonstrated a normal liver, bile duct without stones, and findings that were consistent with focal pancreatitis. The patient's history was significant for concomitant use of enalapril and simvastatin; both have been associated with pancreatitis, but the patient had been taking these medications for at least 5 years without adverse effects. Nilotinib was immediately discontinued. Abdominal pain resolved and serum pancreatic enzymes levels returned to normal 2 weeks later. DISCUSSION: One of the adverse effects of some tyrosine kinase inhibitors is increased levels of serum pancreatic enzymes. Accordingly, nilotinib labeling includes "high lipase levels in serum" as an adverse event. There are few case reports of acute pancreatitis associated with nilotinib in the literature and some are incomplete. We present a well-documented case of nilotinib-associated acute pancreatitis. Consistent with Badalov's new classification system for drug-induced acute pancreatitis and with the Naranjo probability scale, this case represents a possible adverse reaction of pancreatitis associated with nilotinib therapy. As rechallenge is unethical, treatment with nilotinib has not been resumed. CONCLUSIONS: This case demonstrates a possible association between acute pancreatitis and nilotinib use. Although a rare phenomenon, clinicians should be alert for signs and symptoms of pancreatitis, as treatment with nilotinib for CML is becoming more common.

Imatinib plasma trough levels in chronic myeloid leukaemia: results of a multicentre study CSTI571AIL11TGLIVEC.

Imatinib has been accepted as frontline treatment for patients with chronic myeloid leukaemia (CML), and patients generally receive doses ranging from 400 to 800 mg/day. Previous studies have demonstrated that maintaining imatinib plasma levels (IMPLs) >1000 ng/mL leads to improved responses and long-term outcomes. However, IMPLs vary among patients because of factors such as drug-drug interactions, adherence, toxicity and differential levels of expression of cellular efflux/influx proteins. In this study, IMPLs were analysed in 191 patients with CML and were compared with achievement of molecular and cytogenetic responses (CyR). IMPLs were also correlated with renal and hepatic dysfunction. Additionally, self-reported adherence was monitored. The median and mean IMPLs were 994 ng/mL and 1070 ± 686 ng/mL, respectively, with 96 patients (50%) achieving plasma levels >1000 ng/mL. Self-reported patient compliance was 98%. Patients who achieved a complete CyR (CCyR) had significantly higher IMPLs (1078 ± 545 ng/mL) than those without CyR (827 ± 323 ng/mL, p = 0.045). When grouped together, patients who achieved a CCyR or partial CyR had significantly higher IMPLs than patients who achieved a minimal CyR or did not achieve a CyR (1066 ng/mL vs 814 ng/mL, p = 0.002). There was no significant difference observed in the IMPLs between patients who achieved molecular responses (n = 177) on treatment (major molecular response, 976 ± 385 ng/mL versus complete molecular response, 1138 ± 809 ng/mL, p = 0.387). Mean IMPLs were similar in patients with or without renal or hepatic impairment. Overall, this study confirmed previous reports that higher IMPLs correlate with clinical responses and demonstrated that imatinib exposure did not differ in patients with or without liver and/or renal dysfunction. The use of IMPL testing and patient diaries may be practical tools for the management of imatinib therapy in patients with CML.