C.L. Beach

Efficacy of azacitidine compared with that of conventional care regimens in the treatment of higher-risk myelodysplastic syndromes: a randomised, open-label, phase III study

BACKGROUND Drug treatments for patients with high-risk myelodysplastic syndromes provide no survival advantage. In this trial, we aimed to assess the effect of azacitidine on overall survival compared with the three commonest conventional care regimens. METHODS In a phase III, international, multicentre, controlled, parallel-group, open-label trial, patients with higher-risk myelodysplastic syndromes were randomly assigned one-to-one to receive azacitidine (75 mg/m(2) per day for 7 days every 28 days) or conventional care (best supportive care, low-dose cytarabine, or intensive chemotherapy as selected by investigators before randomisation). Patients were stratified by French-American-British and international prognostic scoring system classifications; randomisation was done with a block size of four. The primary endpoint was overall survival. Efficacy analyses were by intention to treat for all patients assigned to receive treatment. This study is registered with ClinicalTrials.gov, number NCT00071799. FINDINGS Between Feb 13, 2004, and Aug 7, 2006, 358 patients were randomly assigned to receive azacitidine (n=179) or conventional care regimens (n=179). Four patients in the azacitidine and 14 in the conventional care groups received no study drugs but were included in the intention-to-treat efficacy analysis. After a median follow-up of 21.1 months (IQR 15.1-26.9), median overall survival was 24.5 months (9.9-not reached) for the azacitidine group versus 15.0 months (5.6-24.1) for the conventional care group (hazard ratio 0.58; 95% CI 0.43-0.77; stratified log-rank p=0.0001). At last follow-up, 82 patients in the azacitidine group had died compared with 113 in the conventional care group. At 2 years, on the basis of Kaplan-Meier estimates, 50.8% (95% CI 42.1-58.8) of patients in the azacitidine group were alive compared with 26.2% (18.7-34.3) in the conventional care group (p<0.0001). Peripheral cytopenias were the most common grade 3-4 adverse events for all treatments. INTERPRETATION Treatment with azacitidine increases overall survival in patients with higher-risk myelodysplastic syndromes relative to conventional care.

Further Analysis of Trials With Azacitidine in Patients With Myelodysplastic Syndrome: Studies 8421, 8921, and 9221 by the Cancer and Leukemia Group B

PURPOSE Within the last two decades, a new understanding of the biology of myelodysplastic syndrome (MDS) has developed. With this understanding, new classification systems, such as the WHO diagnostic criteria, and the International Prognostic Scoring System and response criteria guidelines reported by the International Working Group (IWG) have been developed. We report the combined results of three previously reported clinical trials (n = 309) with azacitidine using the WHO classification system for MDS and acute myeloid leukemia (AML) and IWG criteria for response. PATIENTS AND METHODS Data from three sequential Cancer and Leukemia Group B trials with azacitidine were recollected and reanalyzed as part of the New Drug Application process. The trials were conducted with either intravenous or subcutaneous azacitidine (75 mg/m2/d for 7 days every 28 days). RESULTS Complete remissions were seen in 10% to 17% of azacitidine-treated patients; partial remissions were rare; 23% to 36% of patients had hematologic improvement (HI). The median number of cycles to first response was three, and 90% of responses were seen by cycle 6. Using current WHO criteria, 103 patients had AML at baseline; 35% to 48% had HI or better responses. The median survival time for the 27 AML patients randomly assigned to azacitidine was 19.3 months compared with 12.9 months for the 25 patients assigned to observation. Furthermore, azacitidine did not increase the rate of infection or bleeding above the rate caused by underlying disease. CONCLUSION Azacitidine provides important clinical benefits for patients with high-risk MDS.

International phase 3 study of azacitidine vs conventional care regimens in older patients with newly diagnosed AML with >30% blasts

This multicenter, randomized, open-label, phase 3 trial evaluated azacitidine efficacy and safety vs conventional care regimens (CCRs) in 488 patients age ≥65 years with newly diagnosed acute myeloid leukemia (AML) with >30% bone marrow blasts. Before randomization, a CCR (standard induction chemotherapy, low-dose ara-c, or supportive care only) was preselected for each patient. Patients then were assigned 1:1 to azacitidine (n = 241) or CCR (n = 247). Patients assigned to CCR received their preselected treatment. Median overall survival (OS) was increased with azacitidine vs CCR: 10.4 months (95% confidence interval [CI], 8.0-12.7 months) vs 6.5 months (95% CI, 5.0-8.6 months), respectively (hazard ratio [HR] was 0.85; 95% CI, 0.69-1.03; stratified log-rank P = .1009). One-year survival rates with azacitidine and CCR were 46.5% and 34.2%, respectively (difference, 12.3%; 95% CI, 3.5%-21.0%). A prespecified analysis censoring patients who received AML treatment after discontinuing study drug showed median OS with azacitidine vs CCR was 12.1 months (95% CI, 9.2-14.2 months) vs 6.9 months (95% CI, 5.1-9.6 months; HR, 0.76; 95% CI, 0.60-0.96; stratified log-rank P = .0190). Univariate analysis showed favorable trends for azacitidine compared with CCR across all subgroups defined by baseline demographic and disease features. Adverse events were consistent with the well-established safety profile of azacitidine. Azacitidine may be an important treatment option for this difficult-to-treat AML population. This trial was registered at www.clinicaltrials.gov as #NCT01074047.

Prognostic factors for response and overall survival in 282 patients with higher-risk myelodysplastic syndromes treated with azacitidine

Prognostic factors for response and survival in higher-risk myelodysplastic syndrome patients treated with azacitidine (AZA) remain largely unknown. Two hundred eighty-two consecutive high or intermediate-2 risk myelodysplastic syndrome patients received AZA in a compassionate, patient-named program. Diagnosis was RA/RARS/RCMD in 4%, RAEB-1 in 20%, RAEB-2 in 54%, and RAEB-t (AML with 21%-30% marrow blasts) in 22%. Cytogenetic risk was good in 31%, intermediate in 17%, and poor in 47%. Patients received AZA for a median of 6 cycles (1-52). Previous low-dose cytosine arabinoside treatment (P = .009), bone marrow blasts > 15% (P = .004), and abnormal karyotype (P = .03) independently predicted lower response rates. Complex karyotype predicted shorter responses (P = .0003). Performance status ≥ 2, intermediate- and poor-risk cytogenetics, presence of circulating blasts, and red blood cell transfusion dependency ≥ 4 units/8 weeks (all P < 10(-4)) independently predicted poorer overall survival (OS). A prognostic score based on those factors discriminated 3 risk groups with median OS not reached, 15.0 and 6.1 months, respectively (P < 10(-4)). This prognostic score was validated in an independent set of patients receiving AZA in the AZA-001 trial (P = .003). Achievement of hematological improvement in patients who did not obtain complete or partial remission was associated with improved OS (P < 10(-4)). In conclusion, routine tests can identify subgroups of patients with distinct prognosis with AZA treatment.

Outcome of High-Risk Myelodysplastic Syndrome After Azacitidine Treatment Failure

PURPOSE Azacitidine (AZA) is the current standard of care for high-risk (ie, International Prognostic Scoring System high or intermediate 2) myelodysplastic syndrome (MDS), but most patients will experience primary or secondary treatment failure. The outcome of these patients has not yet been described. PATIENTS AND METHODS Overall, 435 patients with high-risk MDS and former refractory anemia with excess blasts in transformation (RAEB-T) were evaluated for outcome after AZA failure. The cohort of patients included four data sets (ie, AZA001, J9950, and J0443 trials and the French compassionate use program). RESULTS The median follow-up after AZA failure was 15 months. The median overall survival was 5.6 months, and the 2-year survival probability was 15%. Increasing age, male sex, high-risk cytogenetics, higher bone marrow blast count, and the absence of prior hematologic response to AZA were associated with significantly worse survival in multivariate analysis. Data on treatment administered after AZA failure were available for 270 patients. Allogeneic stem-cell transplantation and investigational agents were associated with a better outcome when compared with conventional clinical care. CONCLUSION Outcome after AZA failure is poor. Our results should serve as a basis for designing second-line clinical trials in this population.

Hematologic Response to Three Alternative Dosing Schedules of Azacitidine in Patients With Myelodysplastic Syndromes

PURPOSE Azacitidine (AZA) is effective treatment for myelodysplastic syndromes (MDS) at a dosing schedule of 75 mg/m(2)/d subcutaneously for 7 days every 4 weeks. The initial phase of this ongoing multicenter, community-based, open-label study evaluated three alternative AZA dosing schedules without weekend dosing. PATIENTS AND METHODS MDS patients were randomly assigned to one of three regimens every 4 weeks for six cycles: AZA 5-2-2 (75 mg/m(2)/d subcutaneously for 5 days, followed by 2 days no treatment, then 75 mg/m(2)/d for 2 days); AZA 5-2-5 (50 mg/m(2)/d subcutaneously for 5 days, followed by 2 days no treatment, then 50 mg/m(2)/d for 5 days); or AZA 5 (75 mg/m(2)/d subcutaneously for 5 days). RESULTS Of patients randomly assigned to AZA 5-2-2 (n = 50), AZA 5-2-5 (n = 51), or AZA 5 (n = 50), most were French-American-British (FAB) lower risk (refractory anemia [RA]/RA with ringed sideroblasts/chronic myelomonocytic leukemia with < 5% bone marrow blasts, 63%) or RA with excess blasts (30%), and 79 (52%) completed > or = six treatment cycles. Hematologic improvement (HI) was achieved by 44% (22 of 50), 45% (23 of 51), and 56% (28 of 50) of AZA 5-2-2, AZA 5-2-5, and AZA 5 arms, respectively. Proportions of RBC transfusion-dependent patients who achieved transfusion independence were 50% (12 of 24), 55% (12 of 22), and 64% (16 of 25), and of FAB lower-risk transfusion-dependent patients were 53% (nine of 17), 50% (six of 12), and 61% (11 of 18), respectively. In the AZA 5-2-2, AZA 5-2-5, and AZA 5 groups, 84%, 77%, and 58%, respectively, experienced > or = 1 grade 3 to 4 adverse events. CONCLUSION All three alternative dosing regimens produced HI, RBC transfusion independence, and safety responses consistent with the currently approved AZA regimen. These results support AZA benefits in transfusion-dependent lower-risk MDS patients.

Role of Reduced-Intensity Conditioning Allogeneic Hematopoietic Stem-Cell Transplantation in Older Patients With De Novo Myelodysplastic Syndromes: An International Collaborative Decision Analysis

PURPOSE Myelodysplastic syndromes (MDS) are clonal hematopoietic disorders that are more common in patients aged ≥ 60 years and are incurable with conventional therapies. Reduced-intensity conditioning (RIC) allogeneic hematopoietic stem-cell transplantation is potentially curative but has additional mortality risk. We evaluated RIC transplantation versus nontransplantation therapies in older patients with MDS stratified by International Prognostic Scoring System (IPSS) risk. PATIENTS AND METHODS A Markov decision model with quality-of-life utility estimates for different MDS and transplantation states was assessed. Outcomes were life expectancy (LE) and quality-adjusted life expectancy (QALE). A total of 514 patients with de novo MDS aged 60 to 70 years were evaluated. Chronic myelomonocytic leukemia, isolated 5q- syndrome, unclassifiable, and therapy-related MDS were excluded. Transplantation using T-cell depletion or HLA-mismatched or umbilical cord donors was also excluded. RIC transplantation (n = 132) stratified by IPSS risk was compared with best supportive care for patients with nonanemic low/intermediate-1 IPSS (n = 123), hematopoietic growth factors for patients with anemic low/intermediate-1 IPSS (n = 94), and hypomethylating agents for patients with intermediate-2/high IPSS (n = 165). RESULTS For patients with low/intermediate-1 IPSS MDS, RIC transplantation LE was 38 months versus 77 months with nontransplantation approaches. QALE and sensitivity analysis did not favor RIC transplantation across plausible utility estimates. For intermediate-2/high IPSS MDS, RIC transplantation LE was 36 months versus 28 months for nontransplantation therapies. QALE and sensitivity analysis favored RIC transplantation across plausible utility estimates. CONCLUSION For patients with de novo MDS aged 60 to 70 years, favored treatments vary with IPSS risk. For low/intermediate-1 IPSS, nontransplantation approaches are preferred. For intermediate-2/high IPSS, RIC transplantation offers overall and quality-adjusted survival benefit.

Management and supportive care measures for adverse events in patients with myelodysplastic syndromes treated with azacitidine

Objective:  Myelodysplastic syndrome (MDS) treatment can initially worsen patients’ clinical condition and they may discontinue therapy before achieving benefit. We present previously unpublished data from two large phase III trials describing common adverse events (AEs) associated with azacitidine and methods to manage them.

Effects of azacitidine compared with conventional care regimens in elderly (≥ 75 years) patients with higher-risk myelodysplastic syndromes.

This analysis compared azacitidine (AZA) to conventional care regimens (CCR) and their associated overall survival (OS) and tolerability in the subset of 87 elderly (≥ 75 years) patients with higher-risk MDS (FAB: RAEB, RAEB-t, CMML and IPSS: Int-2 or High) from the AZA-001 trial. Patients were randomized to AZA (75 mg/m(2)/daysubcutaneously × 7 days every 28 days) (n=38) or CCR (n=49) and had median ages of 78 and 77 years, respectively. AZA significantly improved OS vs CCR (HR: 0.48 [95%CI: 0.26, 0.89]; p=0.0193) and 2-year OS rates were 55% vs 15% (p<0.001), respectively. AZA was generally well tolerated compared with CCR, which was primarily best supportive care (67%). Grade 3-4 anemia, neutropenia, and thrombocytopenia with AZA vs CCR were 13% vs 4%, 61% vs 17%, and 50% vs 30%, respectively. Given this efficacy and tolerability, AZA should be considered the treatment of choice in patients aged ≥ 75 years with good performance status and higher-risk MDS.

Bioavailability of Azacitidine Subcutaneous Versus Intravenous in Patients With the Myelodysplastic Syndromes

The primary objectives of this study were to characterize the absolute bioavailability of azacitidine after subcutaneous (SC) administration and to compare the single‐dose pharmacokinetics of azacitidine following SC and intravenous (IV) administration. Six patients with myelodysplastic syndromes were randomly assigned according to a crossover design to treatment A, consisting of azacitidine administered as a single 75‐mg/m2 SC dose, or treatment B, consisting of azacitidine administered as a single 75‐mg/m2 IV infusion dose over 10 minutes. A minimum of 7 days and a maximum of 28 days were permitted between treatments. The study demonstrated good bioavailability of a SC azacitidine dose compared to an IV infusion treatment. The exposure profiles following SC drug administration illustrate measurable azacitidine levels with bioavailability (AUC) values within 89% of those measured following IV administration (range, 70%‐112%). The median IV half‐life was 0.36 ± 0.02 hours compared to 0.69 ± 0.14 hours for SC administration. Regardless of the route of administration, a single dose of azacitidine, 75 mg/m2, was generally well tolerated.