Population Pharmacokinetics of Oral Azacitidine, and Exposure-Response Analysis in Acute Myeloid Leukemia

Oral azacitidine (oral-AZA) maintenance is approved for adults with acute myeloid leukemia (AML) in remission post-intensive chemotherapy, not proceeding to hematopoietic stem cell transplantation. This study aimed to develop a population pharmacokinetic (PopPK) model to characterize oral-AZA concentration-time profiles in patients with AML, myelodysplastic syndrome, or chronic myelomonocytic leukemia. PopPK-estimated exposure parameters were used to evaluate exposure-response relationships in the phase III QUAZAR AML-001 study. The PopPK dataset comprised 286 patients with 1,933 evaluable oral-AZA concentration records. The final PopPK model was a one-compartment model with first-order absorption incorporating an absorption lag time and first-order elimination. Regression analyses identified two oral-AZA exposure parameters (area under the plasma concentration-time curve at steady state (AUCss ); maximum plasma concentration (Cmax )) as statistically significant predictors for relapse-free survival (hazard ratio (HR) = 0.521, P < 0.001; HR = 0.630, P = 0.013; respectively), and AUCss as a significant predictor for overall survival (HR = 0.673, P = 0.042). The probability of grade ≥ 3 neutropenia was significantly increased with increases in AUCss (odds ratio (OR) = 5.71, 95% confidence interval (CI) = 2.73-12.62, P < 0.001), cumulative AUC through cycles 1 to 6 (OR = 2.71, 95% CI = 1.76-4.44, P < 0.001), and Cmax at steady-state (OR = 2.38, 95% CI = 1.23-4.76, P = 0.012). A decreasing trend was identified between AUCss and relapse-related schedule extensions, vs. an increasing trend between AUCss and event-related dose reductions. As the majority (56.8%) of patients required no dose modifications, and the proportions requiring schedule extension (19.4%) or dose reduction (22.9%) were almost equal, oral-AZA 300 mg once daily for 14 days is the optimal dosing schedule balancing survival benefit and safety risk.

Oral azacitidine modulates the bone marrow microenvironment in patients with acute myeloid leukaemia in remission: A subanalysis from the QUAZAR AML-001 trial

Oral azacitidine (Oral-AZA) maintenance therapy improved relapse-free (RFS) and overall survival (OS) significantly versus placebo for AML patients in remission after intensive chemotherapy (IC) in the phase 3 QUAZAR AML-001 study. Immune profiling was performed on the bone marrow (BM) at remission and on-treatment in a subset of patients with the aim of identifying prognostic immune features and evaluating associations of on-treatment immune effects by Oral-AZA with clinical outcomes. Post-IC, increased levels of lymphocytes, monocytes, T cells and CD34 + CD117+ BM cells were prognostically favourable for RFS. CD3+ T-cell counts were significantly prognostic for RFS in both treatment arms. At baseline, high expression of the PD-L1 checkpoint marker was identified on a subset of CD34 + CD117+ BM cells; many of which were PD-L2+. High co-expression of T-cell exhaustion markers PD-1 and TIM-3 was associated with inferior outcomes. Oral-AZA augmented T-cell numbers during early treatment, increased CD4+:CD8+ ratios and reversed T-cell exhaustion. Unsupervised clustering analysis identified two patient subsets defined by T-cell content and expression of T-cell exhaustion markers that were enriched for MRD negativity. These results indicate that Oral-AZA modulates T-cell activity in the maintenance setting of AML, and these immune-mediated responses are associated with clinical outcomes.

Prognostic impact of NPM1 and FLT3 mutations in patients with AML in first remission treated with oral azacitidine

The randomized, placebo-controlled, phase 3 QUAZAR AML-001 trial (ClinicalTrials.gov identifier: NCT01757535) evaluated oral azacitidine (Oral-AZA) in patients with acute myeloid leukemia (AML) in first remission after intensive chemotherapy (IC) who were not candidates for hematopoietic stem cell transplantation. Eligible patients were randomized 1:1 to Oral-AZA 300 mg or placebo for 14 days per 28-day cycle. We evaluated relapse-free survival (RFS) and overall survival (OS) in patient subgroups defined by NPM1 and FLT3 mutational status at AML diagnosis and whether survival outcomes in these subgroups were influenced by presence of post-IC measurable residual disease (MRD). Gene mutations at diagnosis were collected from patient case report forms; MRD was determined centrally by multiparameter flow cytometry. Overall, 469 of 472 randomized patients (99.4%) had available mutational data; 137 patients (29.2%) had NPM1 mutations (NPM1mut), 66 patients (14.1%) had FLT3 mutations (FLT3mut; with internal tandem duplications [ITD], tyrosine kinase domain mutations [TKDmut], or both), and 30 patients (6.4%) had NPM1mut and FLT3-ITD at diagnosis. Among patients with NPM1mut, OS and RFS were improved with Oral-AZA by 37% (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.41-0.98) and 45% (HR, 0.55; 95% CI, 0.35-0.84), respectively, vs placebo. Median OS was improved numerically with Oral-AZA among patients with NPM1mut whether without MRD (48.6 months vs 31.4 months with placebo) or with MRD (46.1 months vs 10.0 months with placebo) post-IC. Among patients with FLT3mut, Oral-AZA improved OS and RFS by 37% (HR, 0.63; 95% CI, 0.35-1.12) and 49% (HR, 0.51; 95% CI, 0.27-0.95), respectively, vs placebo. Median OS with Oral-AZA vs placebo was 28.2 months vs 16.2 months, respectively, for patients with FLT3mut and without MRD and 24.0 months vs 8.0 months for patients with FLT3mut and MRD. In multivariate analyses, Oral-AZA significantly improved survival independent of NPM1 or FLT3 mutational status, cytogenetic risk, or post-IC MRD status.

Impact of Lenalidomide Treatment on Overall Survival in Patients With Lower-Risk, Transfusion-Dependent Myelodysplastic Syndromes

BACKGROUND

For patients with lower-risk (LR) myelodysplastic syndromes (MDS), overall survival (OS) is rarely a primary clinical trial endpoint. Treatments such as lenalidomide can reduce red blood cell (RBC) transfusion burden (TB) and serum ferritin, but the long-term impact on OS remains undetermined.

PATIENTS AND METHODS

Data from 3 trials evaluating lenalidomide in patients with LR-MDS (the phase 2 MDS-003 and phase 3 MDS-004 trials in del[5q]; the phase 3 trial MDS-005 in non-del[5q] patients) were pooled. Predictors of OS were assessed by multivariate analysis using time-dependent models for TB and RBC transfusion independence (RBC-TI), and a landmark analysis of RBC-TI at 17 weeks. Separate analyses using MDS-004 and MDS-005 data determined the relationship between OS and serum ferritin.

RESULTS

Median follow-up for MDS-003, MDS-004, and MDS-005 was 3.2, 3.0, and 1.7 years, respectively. In multivariate analyses, transfusion of ≥6 RBC units over 8 weeks was a significant predictor of shorter OS vs. 0 units in the time-dependent TB model (hazard ratio [HR] 4.65; 95% confidence interval [CI] 3.32-6.52; P < .0001). RBC-TI achievement was associated with prolonged OS in the time-dependent (HR 0.48; 95% CI 0.37-0.62; P < .0001) and landmark model (HR 0.57; 95% CI 0.44-0.75; P < .0001). Increased serum ferritin was associated with shorter OS (P < .0001).

CONCLUSION

This analysis of prospective trial data in patients with LR-MDS confirms lenalidomide may improve OS by reducing TB and serum ferritin. OS should be considered as an endpoint in future lower risk MDS clinical trials.

Oral Azacitidine (CC-486) for the Treatment of Myeloid Malignancies

Epigenetic dysregulation leads to aberrant DNA hypermethylation and is common in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). A large number of clinical trials in AML, MDS, and other hematologic malignancies have assessed hypomethylating agents (HMAs), used alone or in combination with other drugs, in the frontline, maintenance, relapsed/refractory, and peritransplant settings. Effective maintenance therapy has long been a goal for patients with AML in remission. Previous large, randomized clinical trials of maintenance with HMAs or other agents had not shown meaningful improvement in overall survival. Oral azacitidine (Oral-AZA [CC-486]) is approved in the United States, Canada, and European Union for treatment of adult patients with AML in first complete remission (CR) or CR with incomplete blood count recovery (CRi) following intensive induction chemotherapy who are ineligible for hematopoietic cell transplant. Regulatory approvals of Oral-AZA were based on outcomes from the randomized, phase III QUAZAR AML-001 trial, which showed a median overall survival advantage of 9.9 months with Oral-AZA versus placebo. Oral-AZA allows convenient extended AZA dosing for 14 days per 28-day treatment cycle, which is not feasible with injectable AZA. Focusing on AML and MDS, this report reviews the rationale for the use of orally bioavailable AZA and its potential use in all-oral combination therapy regimens; the unique pharmacokinetic and pharmacodynamic profile of Oral-AZA compared with injectable AZA; the clinical safety and efficacy of Oral-AZA maintenance therapy in patients with AML in first remission and for treatment of patients with active MDS; and ongoing Oral-AZA clinical trials.

Management of adverse events in patients with acute myeloid leukemia in remission receiving oral azacitidine: experience from the phase 3 randomized QUAZAR AML-001 trial

Background

Most older patients with acute myeloid leukemia (AML) who attain morphologic remission with intensive chemotherapy (IC) will eventually relapse and post-relapse prognosis is dismal. In the pivotal QUAZAR AML-001 trial, oral azacitidine maintenance therapy significantly prolonged overall survival by 9.9 months (P < 0.001) and relapse-free survival by 5.3 months (P < 0.001) compared with placebo in patients with AML in first remission after IC who were not candidates for transplant. Currently, the QUAZAR AML-001 trial provides the most comprehensive safety information associated with oral azacitidine maintenance therapy. Reviewed here are common adverse events (AEs) during oral azacitidine treatment in QUAZAR AML-001, and practical recommendations for AE management based on guidance from international cancer consortiums, regulatory authorities, and the authors’ clinical experience treating patients in the trial.

Methods

QUAZAR AML-001 is an international, placebo-controlled randomized phase 3 study. Patients aged ≥ 55 years with AML and intermediate- or poor-risk cytogenetics at diagnosis, who had attained first complete remission (CR) or CR with incomplete blood count recovery (CRi) within 4 months before study entry, were randomized 1:1 to receive oral azacitidine 300 mg or placebo once-daily for 14 days in repeated 28-day cycles. Safety was assessed in all patients who received ≥ 1 dose of study drug.

Results

A total of 469 patients received oral azacitidine (n = 236) or placebo (n = 233). Median age was 68 years. Patients received a median of 12 (range 1–80) oral azacitidine treatment cycles or 6 (1–73) placebo cycles. Gastrointestinal AEs were common and typically low-grade. The most frequent grade 3–4 AEs during oral azacitidine therapy were hematologic events. AEs infrequently required permanent discontinuation of oral azacitidine (13%), suggesting they were effectively managed with use of concomitant medications and oral azacitidine dosing modifications.

Conclusion

Oral azacitidine maintenance had a generally favorable safety profile. Prophylaxis with antiemetic agents, and blood count monitoring every other week, are recommended for at least the first 2 oral azacitidine treatment cycles, and as needed thereafter. Awareness of the type, onset, and duration of common AEs, and implementation of effective AE management, may maximize treatment adherence and optimize the survival benefits of oral azacitidine AML remission maintenance therapy.

Trial registration This trial is registered on clinicaltrials.gov: NCT01757535 as of December 2012.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-021-01142-x.

Abstract 505: Oral azacitidine modulates the immune microenvironment in acute myeloid leukemia (AML) patients in remission: A subanalysis from the QUAZAR AML-001 Trial

BACKGROUND The immunologic effects of maintenance therapy in patients (pts) with AML in remission are not well-characterized but of high clinical interest, as rapid recovery of bone marrow (BM) after intensive chemotherapy (IC) may help delay relapse. Post IC, immunological interactions in the BM microenvironment present several immunosuppressive mechanisms. PD-L1 is commonly overexpressed on AML blasts, which is associated with worse prognosis. Oral azacitidine (Oral-AZA [CC-486]) is a hypomethylating agent recently approved in the US for pts with AML in complete remission (CR) or CR with incomplete hematologic recovery (CRi). To better understand the effects of Oral-AZA on immune cells, checkpoint expression of PD-L1/2 on AML blasts and normal myeloid progenitors (MPs), and the kinetics of T cell recovery and activation/exhaustion (eg, PD1, TIM3) were assessed.

METHODS Biomarker-evaluable pts aged ≥ 55 years with AML were randomized 1:1 to Oral-AZA 300 mg (n=56) or placebo (PBO, n=52) post IC within 4 months of achieving CR. Flow cytometry evaluations of BM aspirates were performed at screening (ie, baseline [BL]), every 3 cycles until cycle 24 and every 6 cycles thereafter to cycle 36, or as clinically indicated. Correlative analyses of baseline immune parameters with median (med) relapse-free survival (RFS) were computed using Kaplan-Meier methods.

RESULTS In the biomarker-evaluable pts, PD-L1 and PD-L2 expression at BL were higher on AML blasts (med intensity 7.1 and 2.9) than normal MPs (0.7 and 1.6). Most AML blasts were PD-L2+ (79%), whereas only 1.9% were PD-L1+. When stratified by the med, higher BL CD3 T cell numbers (as a % of total BM ) were associated with favorable RFS in both Tx arms (Oral-AZA: ≥ med, 562 days[d] and &lt; med, 235d [P = .0308]; PBO: ≥ med, 325d and &lt; med, 155d [P = .0391]). At cycle 3, pts in the Oral-AZA arm had a 1.7-fold increase in CD3 T cells from BL (PBO, 1.1; P = .0450), suggesting Oral-AZA can promote immunologic recovery during early Tx cycles. There was an inverse correlation between T cell exhaustion marker phenotypes (PD1/TIM3+) with CD4 (r = -.5967; P &lt; .0001) and CD8 (r = -.2484; P = .0095) T cell numbers. An increase in RFS was seen in the PBO arm with lower PD1/TIM3+ CD4 numbers (&lt; med, 429d; ≥ med, 155d; P = .0037), with a nominal increase observed in the Oral-AZA arm (&lt; med, 428d; ≥ med, 303d; P = .6764). In a subset of pts, Oral-AZA appeared to suppress CD4 T cell exhaustion (PD1/TIM3+) compared with PBO.

CONCLUSIONS Pts in CR/CRi post-IC have a unique immune profile defined by high expression of PD-L1 on a subset of blasts and a high % of PD-L2+ blasts. A higher BL CD3 T cell count after IC in BM was prognostic. Additionally, Oral-AZA appears to contribute to an increase in T cells while also suppressing exhaustion, potentially promoting T cell signaling that could activate functional immune-mediated responses against residual leukemic cells.

Citation Format: Daniel L. Menezes, Wendy L. See, Alberto Risueno, Jianglin Ma, Ignazia La Torre, Barry Skikne, CL Beach, Keshava Kumar, Anjan Thakurta. Oral azacitidine modulates the immune microenvironment in acute myeloid leukemia (AML) patients in remission: A subanalysis from the QUAZAR AML-001 Trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 505.

Prognostic factors of overall (OS) and relapse-free survival (RFS) for patients with acute myeloid leukemia (AML) in remission after intensive chemotherapy (IC): Multivariate analyses from the QUAZAR AML-001 trial of oral azacitidine (Oral-AZA)

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Background: Demographic and disease factors influence outcomes for patients (pts) with AML. In the phase 3 QUAZAR AML-001 trial, Oral-AZA significantly prolonged OS and RFS vs. placebo (PBO) for pts with AML in first remission after IC (Wei, NEJM, 2020). Univariate analyses showed OS and RFS benefits with Oral-AZA vs. PBO across pt subgroups defined by baseline (BL) characteristics. MV analyses were performed to identify BL characteristics independently predictive of OS/RFS in QUAZAR AML-001, and to assess Tx effects of Oral-AZA vs. PBO on survival when adjusted for BL factors. Methods: Pts were aged ≥55 yrs with AML in complete remission (CR) or CR with incomplete count recovery (CRi) after induction ± consolidation. Within 4 months of CR/CRi, pts were randomized 1:1 to receive Oral-AZA 300 mg or PBO for 14d/28d cycle. Cox proportional hazards models were used to estimate Tx effects of Oral-AZA vs. PBO on OS and RFS, adjusting for BL age, sex, ECOG PS score, cytogenetic risk at diagnosis (Dx), prior MDS, geographic region, CR/CRi after induction (per investigator) and at BL (per sponsor), MRD status, receipt of consolidation, number of consolidation cycles, platelet count, and ANC. In a stepwise procedure, randomized Tx and BL variables were selected incrementally into a Cox model if P ≤ 0.25. After each addition, the contribution of the covariate adjusted for other covariates in the model was evaluated and retained in the model if P ≤ 0.15. Results : Oral-AZA Tx remained a significant independent predictor of improved OS (HR 0.70) and RFS (HR 0.57) vs. PBO after controlling for BL characteristics (Table). MRD status, cytogenetic risk, and pt age were each also independently predictive of OS and RFS. Response after induction (CR vs. CRi) and BL ANC were predictive of OS but not RFS, whereas prior MDS, CR/CRi at BL, and number of consolidation cycles were only predictive of RFS. Conclusions: Tx with Oral-AZA reduced the risk of death by 30% and risk of relapse by 43% vs. PBO independent of BL characteristics. Cytogenetic risk at Dx, MRD status, and pt age also independently predicted survival outcomes. Clinical trial information: NCT01757535. [Table: see text]

Phase III, Randomized, Placebo-Controlled Trial of CC-486 (Oral Azacitidine) in Patients With Lower-Risk Myelodysplastic Syndromes

PURPOSE

Treatment options are limited for patients with lower-risk myelodysplastic syndromes (LR-MDS). This phase III, placebo-controlled trial evaluated CC-486 (oral azacitidine), a hypomethylating agent, in patients with International Prognostic Scoring System LR-MDS and RBC transfusion-dependent anemia and thrombocytopenia.

METHODS

Patients were randomly assigned 1:1 to CC-486 300-mg or placebo for 21 days/28-day cycle. The primary end point was RBC transfusion independence (TI).

RESULTS

Two hundred sixteen patients received CC-486 (n = 107) or placebo (n = 109). The median age was 74 years, median platelet count was 25 × 10⁹/L, and absolute neutrophil count was 1.3 × 10⁹/L. In the CC-486 and placebo arms, 31% and 11% of patients, respectively, achieved RBC-TI (P = .0002), with median durations of 11.1 and 5.0 months. Reductions of ≥ 4 RBC units were attained by 42.1% and 30.6% of patients, respectively, with median durations of 10.0 and 2.3 months, and more CC-486 patients had ≥ 1.5 g/dL hemoglobin increases from baseline (23.4% v 4.6%). Platelet hematologic improvement rate was higher with CC-486 (24.3% v 6.5%). Underpowered interim overall survival analysis showed no difference between CC-486 and placebo (median, 17.3 v 16.2 months; P = .96). Low-grade GI events were the most common adverse events in both arms. In the CC-486 and placebo arms, 90% and 73% of patients experienced a grade 3-4 adverse event. Overall death rate was similar between arms, but there was an imbalance in deaths during the first 56 days (CC-486, n = 16; placebo, n = 6), most related to infections; the median pretreatment absolute neutrophil count for the 16 CC-486 patients was 0.57 × 10⁹/L.

CONCLUSION

CC-486 significantly improved RBC-TI rate and induced durable bilineage improvements in patients with LR-MDS and high-risk disease features. More early deaths occurred in the CC-486 arm, most related to infections in patients with significant pretreatment neutropenia. Further evaluation of CC-486 in MDS is needed.

Oral Azacitidine Maintenance Therapy for Acute Myeloid Leukemia in First Remission

BACKGROUND

Although induction chemotherapy results in remission in many older patients with acute myeloid leukemia (AML), relapse is common and overall survival is poor.

METHODS

We conducted a phase 3, randomized, double-blind, placebo-controlled trial of the oral formulation of azacitidine (CC-486, a hypomethylating agent that is not bioequivalent to injectable azacitidine), as maintenance therapy in patients with AML who were in first remission after intensive chemotherapy. Patients who were 55 years of age or older, were in complete remission with or without complete blood count recovery, and were not candidates for hematopoietic stem-cell transplantation were randomly assigned to receive CC-486 (300 mg) or placebo once daily for 14 days per 28-day cycle. The primary end point was overall survival. Secondary end points included relapse-free survival and health-related quality of life.

RESULTS

A total of 472 patients underwent randomization; 238 were assigned to the CC-486 group and 234 were assigned to the placebo group. The median age was 68 years (range, 55 to 86). Median overall survival from the time of randomization was significantly longer with CC-486 than with placebo (24.7 months and 14.8 months, respectively; P<0.001). Median relapse-free survival was also significantly longer with CC-486 than with placebo (10.2 months and 4.8 months, respectively; P<0.001). Benefits of CC-486 with respect to overall and relapse-free survival were shown in most subgroups defined according to baseline characteristics. The most common adverse events in both groups were grade 1 or 2 gastrointestinal events. Common grade 3 or 4 adverse events were neutropenia (in 41% of patients in the CC-486 group and 24% of patients in the placebo group) and thrombocytopenia (in 22% and 21%, respectively). Overall health-related quality of life was preserved during CC-486 treatment.

CONCLUSIONS

CC-486 maintenance therapy was associated with significantly longer overall and relapse-free survival than placebo among older patients with AML who were in remission after chemotherapy. Side effects were mainly gastrointestinal symptoms and neutropenia. Quality-of-life measures were maintained throughout treatment. (Supported by Celgene; QUAZAR AML-001 ClinicalTrials.gov number, NCT01757535.).

Health-related quality of life (HRQoL) in the phase III QUAZAR-AML-001 trial of CC-486 as maintenance therapy for patients with acute myeloid leukemia (AML) in first remission following induction chemotherapy (IC)

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Background: Effective AML maintenance treatment (Tx) should decrease the risk of relapse and prolong survival without compromising HRQoL. In the placebo (PBO)-controlled phase III QUAZAR AML-001 trial (NCT01757535), CC-486, an oral hypomethylating agent, provided significant improvements in overall (OS) and relapse-free survival (RFS) in patients (pts) with AML in first remission following IC. Here we present pt-reported HRQoL outcomes from that study. Methods: Eligible pts were ≥ 55 yrs of age with intermediate- or poor-risk cytogenetics and ECOG PS ≤ 3, and in CR/CRi after IC ± consolidation. Pts were randomized 1:1 to CC-486 300 mg or PBO QD on days (d) 1–14 of 28d Tx cycles. HRQoL was assessed by FACIT-Fatigue scale and EQ-5D-3L health utility index, completed on d1 of each cycle and at end of Tx (EOT). Endpoints include Tx differences in mean changes from baseline (BL), and proportions of pts with clinically meaningful change from BL (improvement, no change, deterioration). Evaluable pts had an HRQoL assessment at BL and ≥ 1 post-BL visit. Stratified ANCOVA models included Tx and BL scores as covariates. Results: In all, 225/238 pts (95%) in the CC-486 arm were evaluable for FACIT-Fatigue and EQ-5D-3L, and 219/234 pts (94%) in the PBO arm were evaluable for FACIT-Fatigue and 217 (93%) for EQ-5D-3L. Pt characteristics were comparable between Tx arms. Most pts (61%) were 65-74 yrs of age. Median number of CC-486 Tx cycles was 12 and PBO cycles was 7. Compliance rates were > 95% at BL and remained high ( > 85%) at all post-BL visits except for EOT. At BL, pts in both Tx arms had comparable low levels of fatigue and generally good HRQoL relative to an age-matched general population. There were no meaningful differences between CC-486 and PBO in mean changes from BL in FACIT-Fatigue or EQ-5D-3L scores at any post-BL visit. There was no statistically significant difference between Tx arms in proportion of pts with a clinically meaningful deterioration in FACIT-Fatigue score at any post-BL visit except at cycle 29 (likely due to chance; no adjustment made for multiple testing), or in EQ-5D-3L at any visit. Median time to deterioration was not significantly different between CC-486 and PBO on the FACIT-Fatigue scale (41 vs 44 weeks, respectively; P = 0.70) or the EQ-5D-3L (200 vs 164 weeks; P = 0.63). Conclusions: HRQoL and low levels of fatigue were preserved with CC-486 maintenance Tx. CC-486 significantly improved OS and RFS while maintaining HRQoL comparable to PBO. Clinical trial information: NCT01757535 .

CC-486 is safe and well-tolerated as maintenance therapy in elderly patients (≥75 years) with acute myeloid leukemia (AML) in first remission following induction chemotherapy: Results from the phase III QUAZAR AML-001 trial

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Background: About 40-50% of older patients (pts) with AML attain complete remission (CR) with induction chemotherapy (IC) but relapse is common.Effective, well-tolerated maintenance treatment (Tx) is needed for older pts in remission who are not eligible for hematopoietic stem cell transplant (HSCT). CC-486 is an oral hypomethylating agent that allows for extended dosing schedules ( >7 days [d]/cycle) to sustain therapeutic activity. In the phase III placebo (PBO)-controlled QUAZAR AML-001 trial (NCT01757535), CC-486 maintenance therapy in pts with AML in first remission following IC produced significant improvements in overall and relapse-free survival. Here we report safety and tolerability findings among pt subgroups defined by age at study entry. Methods: Eligible pts were ≥ 55 yrs of age, with de novo or secondary AML, intermediate or poor risk cytogenetics, and ECOG PS ≤ 3; had achieved first CR or CRi after IC ± consolidation; and were not candidates for HSCT. Within 4 mo of CR/CRi, pts were randomized 1:1 to CC-486 300 mg or PBO QD on d 1–14 of repeated 28d Tx cycles. Safety was assessed across 3 age subgroups (≥ 55 to < 65, ≥ 65 to < 75, and ≥ 75 yrs) in pts who received ≥ 1 dose of study drug. Adverse events (AEs) were coded using MedDRA v. 22.0 and graded by NCI-CTCAE v. 4.0. Results: 469 pts ( >99% of all enrolled pts) were evaluable for safety (CC-486 n = 236; PBO n = 233). Median age was 68 yrs (range 55-86). Age distribution was similar between the two Tx arms (Table). Between Tx arms, AE rates within each age stratum were similar to rates in the overall study population. The most common AEs (any grade) with CC-486 were GI events, which were more frequent than in the PBO arm across age groups. Within the CC-486 arm, AE rates were generally consistent across age groups, except for constipation, which was > 20% more frequent in pts aged ≥ 75 yrs, and thrombocytopenia, which was ≥ 20% less frequent in this group (Table). Overall, 13% and 4% of pts in the CC-486 and PBO groups discontinued Tx due to AEs. Conclusions: In QUAZAR AML-001, CC-486 was generally well tolerated in all age groups, including elderly pts aged ≥ 75 yrs. Clinical trial information: NCT01757535 . [Table: see text]

Escalated dosing schedules of CC-486 for patients experiencing first acute myeloid leukemia (AML) relapse: Results from the phase III QUAZAR AML-001 maintenance trial

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Background: A goal of AML maintenance therapy is to decrease the risk of relapse by suppressing growth of residual leukemic cells post-induction. CC-486 is an oral hypomethylating agent that allows for extended dosing schedules ( >7 days [d]/28d cycle) to sustain therapeutic activity. In the QUAZAR AML-001 trial (NCT01757535), CC-486 maintenance treatment (Tx) significantly prolonged overall (OS) and relapse-free survival vs. placebo (PBO) in pts with AML in first remission following induction chemotherapy (IC), who were not candidates for hematopoietic stem cell transplant (HSCT). Pts initially received CC-486 or PBO for 14d/cycle, but pts who relapsed with 5–15% blasts could receive escalated 21d/cycle dosing. We review outcomes of pts who received 21d dosing in QUAZAR AML-001. Methods: Pts were aged ≥ 55 years, with intermediate- or poor-risk cytogenetics and ECOG PS ≤ 3, and had achieved first CR/CRi after IC ± consolidation. Within 4 mo of CR/CRi, pts were randomized 1:1 to CC-486 300 mg or PBO QD on d 1–14 of 28d Tx cycles. CR/CRi status was assessed every 3 cycles. Pts relapsing with 5%–15% blasts in blood or bone marrow could receive study drug for 21d/cycle at the investigator’s discretion. Tx could continue until > 15% blasts, unacceptable toxicity, or HSCT. Results: 91 patients (CC-486, 51/238 [21%]; PBO, 40/234 [17%]) were assigned to ≥ 1 21d/cycle dosing schedule. Median time to dose escalation was 9.2 mo (range 1.0-52.7) for CC-486 and 6.0 mo (0.5-19.3) for PBO. Median number of 21d dosing cycles was 2.0 (range 1-45) in the CC-486 arm and 2.0 (1-16) in the PBO arm; 43% and 18% of pts, respectively, received > 3 cycles of 21d dosing. Among 78 evaluable pts, 10/43 (23%) CC-486 pts and 4/35 (11%) PBO pts regained CR/CRi (central review) during dose escalation. Median OS from randomization was 22.8 mo vs. 14.6 mo with CC-486 vs. PBO, respectively (HR 0.66 [95%CI 0.42, 1.0]; P = 0.073), and 1-year survival rates were 80.4% vs. 59.5% (+20.9% [95%CI 2.1%, 39.7%]). The most common AEs with first onset during 21d dosing were febrile neutropenia (CC-486 24%, PBO 3%), thrombocytopenia (22%, 23%), anemia (22%, 20%), and neutropenia (20%, 10%). Conclusions: Escalated 21d CC-486 dosing was well tolerated and resulted in prolongation of OS and restoration of remission in approximately one-fourth of pts. Hematologic AEs first reported during escalated dosing in both Tx arms may be due in part to disease relapse. A 21d dosing schedule should be considered for pts receiving CC-486 who experience relapse with 5–15% blasts. Clinical trial information: NCT01757535 .

Achievement of red blood cell transfusion independence in red blood cell transfusion-dependent patients with lower-risk non-del(5q) myelodysplastic syndromes correlates with serum erythropoietin levels

In the randomized, phase 3, MDS-005 study (NCT01029262), lenalidomide-induced red blood cell transfusion independence (RBC-TI) in 27% of transfusion-dependent patients with lower-risk non-del(5q) myelodysplastic syndromes (MDS) ineligible for or refractory to erythropoiesis-stimulating agents. To determine the influence of erythropoietin (EPO) level on response, 155 patients treated with lenalidomide in MDS-005 were categorized into four groups by baseline EPO level. The EPO >500 mU/mL group had higher RBC transfusion burden and the lowest proportion of patients with ring sideroblasts ≥15% versus lower EPO groups. Achievement of RBC-TI ≥8 weeks inversely correlated with EPO level, ranging from 42.5 to 15.5%. EPO level did not affect erythroid hematologic improvement response (36.2-44.4%). This analysis suggests patients with lower EPO levels experience the strongest benefit from lenalidomide. Although meaningful improvements were observed in some patients with EPO level >500 mU/mL, new treatments are needed for this population.

Evaluation of the bioequivalence and food effect on the bioavailability of CC-486 (oral azacitidine) tablets in adult patients with cancer

Purpose

CC-486 is an oral formulation of azacitidine that allows for extended dosing schedules to prolong azacitidine exposure to malignant cells and maximize clinical activity. CC-486 300 mg daily, administered for 14 or 21 days of 28-day treatment cycles, is currently under investigation in two ongoing phase III trials. The 300-mg daily dose in these studies is administered as two 150-mg tablets (Formulation A).

Methods

We evaluated the bioequivalence of one 300-mg CC-486 tablet (Formulation B) with Formulation A and food effect on Formulation B, in adult patients with cancer in a 2-stage crossover design study.

Results

The ratios of the geometric means of the maximum azacitidine plasma concentration (C_max) and of the area under the plasma concentration–time curve from time 0 extrapolated to infinity (AUC_∞) were 101.5% and 105.7%, demonstrating the bioequivalence of Formulations A and B. Formulation B was rapidly absorbed under fasted and fed conditions. The geometric mean of C_max was significantly decreased by ~ 21% in the fed state. Median T_max was reached at 2 h and 1 h post-dose in fed and fasted states, respectively (P < 0.001). Nevertheless, systemic drug exposure (AUC) in fed and fasted states was within the 80–125% boundaries of bioequivalence and differences in C_max and T_max are not expected to have a clinical impact.

Conclusion

The single 300-mg CC-486 tablet was bioequivalent to two 150-mg tablets, which have shown to be efficacious and generally well-tolerated in clinical trials, and can be taken with or without food.

Electronic supplementary material

The online version of this article (10.1007/s00280-020-04037-9) contains supplementary material, which is available to authorized users.

CC-486 (oral azacitidine) in patients with myelodysplastic syndromes with pretreatment thrombocytopenia

Thrombocytopenia is among the strongest predictors of decreased survival for patients with myelodysplastic syndromes (MDS) across all prognostic risk groups. The safety and efficacy of CC-486 (oral azacitidine) was investigated in early-phase studies; we assessed clinical outcomes among subgroups of MDS patients from these studies, defined by presence or lack of pretreatment thrombocytopenia (≤75 × 10⁹/L platelet count). Patients received CC-486 300 mg once-daily for 14 or 21 days of repeated 28-day cycles. Overall, 81 patients with MDS, median age 72 years, comprised the Low Platelets (n = 45) and High Platelets (n = 36) cohorts. Pretreatment median platelet counts were 34 × 10⁹/L and 198 × 10⁹/L, respectively. Grade 3-4 bleeding events occurred in 2 patients in the Low Platelets and 1 patient in the High Platelets groups; events resolved without sequelae. Treatment-related mortality was reported for 7 patients, 5 of whom had pretreatment platelet values <25 × 10⁹/L. Overall response rates were 38% and 46% in the Low Platelets and High Platelets groups, respectively. Five thrombocytopenic patients attained complete remission and 9 attained platelet hematologic improvement. In both cohorts, platelet counts dropped during the first CC-486 treatment cycle, then increased thereafter. Extended CC-486 dosing was generally well tolerated and induced hematologic responses in these patients regardless of pretreatment thrombocytopenia.

Safety profile of lenalidomide in patients with lower-risk myelodysplastic syndromes without del(5q): results of a phase 3 trial

The safety profile of lenalidomide use in lower-risk myelodysplastic syndromes (MDS) patients with del(5q) is well-established, but less is known in non-del(5q) patients. We provide safety data from a randomized, phase 3 trial evaluating lenalidomide in 239 patients with lower-risk non-del(5q) MDS ineligible/refractory to erythropoiesis-stimulating agents (ESAs). Compared with placebo, lenalidomide was associated with a higher incidence of grade 3-4 treatment-emergent adverse events (TEAEs; 86% vs. 44%), but not risk of infection (p = .817) or hemorrhagic events (p = 1.000). Grade 3-4 non-hematologic TEAEs were rare (the incidence of grade 3-4 pneumonia, e.g. was 5.6% in the lenalidomide group and 2.5% in the placebo group). Common grade 1-2 non-hematologic TEAEs did not require dose modifications or treatment discontinuation. Acute myeloid leukemia and second primary malignancies incidence was similar across treatment groups. Lenalidomide had a predictable and manageable safety profile in lower-risk non-del(5q) MDS patients ineligible/refractory to ESAs. Guidance on managing lenalidomide-related TEAEs is provided to help maintain patients on therapy to achieve maximum clinical benefit.

TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT01029262.

Efficacy, safety and pharmacokinetics of subcutaneous azacitidine in Chinese patients with higher risk myelodysplastic syndromes: Results from a multicenter, single-arm, open-label phase 2 study

BACKGROUND

Azacitidine safety and efficacy were established in studies of mainly Caucasian patients. Differences in drug metabolism enzymes between Caucasian and East Asian populations prevent extrapolation of drug effects between these groups. This phase 2 study evaluated azacitidine safety, efficacy and pharmacokinetics in patients with higher-risk myelodysplastic syndromes (HR-MDS) in mainland China.

METHODS

Patients aged ≥18 years with HR-MDS were to receive subcutaneous azacitidine 75 mg/m² /day for 7 days per 28-day cycle, for ≥6 cycles. Pharmacokinetic blood samples were collected in cycle 1 predose on days 5-7, and postdose on day 7. Pharmacokinetic outcomes are descriptively compared with those of a historical North American cohort.

RESULTS

Of 72 participants, 46 (64%) completed ≥6 cycles. Response rate was 96%, driven primarily by stable disease (94%); one patient achieved complete remission. Hematologic improvement was attained by 53% of patients. Azacitidine mean plasma concentration versus time profiles were similar in shape for Chinese (n = 12) and North American (n = 45) patients. Maximum plasma concentration (C_max ) was higher in Chinese patients; however, mean azacitidine exposure (1190 ng·h/mL) was similar to the North American cohort (1021 ng·h/mL). Most common grade 3-4 treatment-emergent adverse events (TEAEs) were thrombocytopenia (69%) and neutropenia (67%).

CONCLUSIONS

Azacitidine was safe and effective in Chinese patients with HR-MDS. Clinical outcomes were comparable to those for primarily Caucasian patients in the phase 3 AZA-001 study. C_max differences between Chinese and North American patients were not associated with differences in TEAE frequency or severity. No initial azacitidine dose adjustment is required for Chinese patients with HR-MDS.

Azacitidine improves clinical outcomes in older patients with acute myeloid leukaemia with myelodysplasia-related changes compared with conventional care regimens

BACKGROUND

Compared with World Health Organization-defined acute myeloid leukaemia (AML) not otherwise specified, patients with AML with myelodysplasia-related changes (AML-MRC) are generally older and more likely to have poor-risk cytogenetics, leading to poor response and prognosis. More than one-half of all older (≥65 years) patients in the phase 3 AZA-AML-001 trial had newly diagnosed AML-MRC.

METHODS

We compared clinical outcomes for patients with AML-MRC treated with azacitidine or conventional care regimens (CCR; induction chemotherapy, low-dose cytarabine, or supportive care only) overall and within patient subgroups defined by cytogenetic risk (intermediate or poor) and age (65-74 years or ≥75 years). The same analyses were used to compare azacitidine with low-dose cytarabine in patients who had been preselected to low-dose cytarabine before they were randomized to receive azacitidine or CCR (ie, low-dose cytarabine).

RESULTS

Median overall survival was significantly prolonged with azacitidine (n = 129) versus CCR (n = 133): 8.9 versus 4.9 months (hazard ratio 0.74, [95%CI 0.57, 0.97]). Among patients with intermediate-risk cytogenetics, median overall survival with azacitidine was 16.4 months, and with CCR was 8.9 months (hazard ratio 0.73 [95%CI 0.48, 1.10]). Median overall survival was significantly improved for patients ages 65-74 years treated with azacitidine compared with those who received CCR (14.2 versus 7.3 months, respectively; hazard ratio 0.64 [95%CI 0.42, 0.97]). Within the subgroup of patients preselected to low-dose cytarabine before randomization, median overall survival with azacitidine was 9.5 months versus 4.6 months with low-dose cytarabine (hazard ratio 0.77 [95%CI 0.55, 1.09]). Within the low-dose cytarabine preselection group, patients with intermediate-risk cytogenetics who received azacitidine had a median overall survival of 14.1 months versus 6.4 months with low-dose cytarabine, and patients aged 65-74 years had median survival of 14.9 months versus 5.2 months, respectively. Overall response rates were similar with azacitidine and CCR (24.8% and 17.3%, respectively), but higher with azacitidine versus low-dose cytarabine (27.2% and 13.9%). Adverse events were generally comparable between the treatment arms.

CONCLUSIONS

Azacitidine may be the preferred treatment for patients with AML-MRC who are not candidates for intensive chemotherapy, particularly patients ages 65-74 years and those with intermediate-risk cytogenetics.

TRIAL REGISTRATION

This study was registered at clinicalTrials.gov on February 16, 2010 ( NCT01074047 ).

Randomized study of continuous high-dose lenalidomide, sequential azacitidine and lenalidomide, or azacitidine in persons 65 years and over with newly-diagnosed acute myeloid leukemia

Therapy of acute myeloid leukemia in older persons is associated with poor outcomes because of intolerance to intensive therapy, resistant disease and co-morbidities. This multi-center, randomized, open-label, phase II trial compared safety and efficacy of three therapeutic strategies in patients 65 years or over with newly-diagnosed acute myeloid leukemia: 1) continuous high-dose lenalidomide (n=15); 2) sequential azacitidine and lenalidomide (n=39); and 3) azacitidine only (n=34). The efficacy end point was 1-year survival. Median age was 76 years (range 66–87 years). Thirteen subjects (15%) had prior myelodysplastic syndrome and 41 (47%) had adverse cytogenetics. One-year survival was 21% [95% confidence interval (CI): 0, 43%] with high-dose lenalidomide, 44% (95%CI: 28, 60%) with sequential azacitidine and lenalidomide, and 52% (95%CI: 35, 70%) with azacitidine only. Lenalidomide at a continuous high-dose schedule was poorly-tolerated resulting in a high rate of early therapy discontinuations. Hazard of death in the first four months was greatest in subjects receiving continuous high-dose lenalidomide; hazards of death thereafter were similar. These data do not favor use of continuous high-dose lenalidomide or sequential azacitidine and lenalidomide over the conventional dose and schedule of azacitidine only in patients aged 65 years or over with newly-diagnosed acute myeloid leukemia. (clinicaltrials.gov identifier: 01358734).

Efficacy, safety, and pharmacokinetics of subcutaneous azacitidine in Taiwanese patients with higher-risk myelodysplastic syndromes

AIM

Clinical and pharmacokinetic effects of azacitidine in higher-risk myelodysplastic syndromes were established in mainly Caucasian populations. Because of inter-ethnic genotype variability of drug-metabolizing enzymes, it is important to evaluate azacitidine in populations expected to use the drug.

METHODS

In this single-arm study, Taiwanese patients with higher-risk myelodysplastic syndromes received azacitidine 75 mg/m² /day for 7 days/28-day cycle for up to six cycles. Response-evaluable patients had baseline and cycle 6 marrow assessments. Clinical outcomes are compared descriptively with those from a phase 3 study comprising mainly Caucasian patients (N = 179). Pharmacokinetics in a subgroup of Taiwanese patients are descriptively compared with a historical control of North American patients (N = 45).

RESULTS

Median age of Taiwanese patients (N = 44) was 64 years (range 36-90), and 46% had poor cytogenetics. Median number of azacitidine cycles was six (1-6). No response-evaluable patient (n = 33) achieved complete or partial remission; however, 22 patients (50%) achieved hematologic improvement, 12 of 32 patients attained RBC transfusion independence and 7 of 18 attained platelet transfusion independence. Most common grade 3-4 treatment-emergent adverse events were neutropenia (52%) and leukopenia (39%). Pharmacokinetic profiles were similar for Taiwanese (N = 12) and North American (N = 45) patients. Maximum plasma concentration was higher in Taiwanese patients; however, mean azacitidine exposure was within the range for North American patients.

CONCLUSION

These data confirm the safety and efficacy of azacitidine in Taiwanese patients with higher-risk myelodysplastic syndromes. Clinical outcomes were generally comparable with those for Caucasian patients. No meaningful differences in azacitidine pharmacokinetics were observed for Taiwanese patients, and no initial dose adjustment is necessary.

Randomized Phase III Study of Lenalidomide Versus Placebo in RBC Transfusion-Dependent Patients With Lower-Risk Non-del(5q) Myelodysplastic Syndromes and Ineligible for or Refractory to Erythropoiesis-Stimulating Agents

PURPOSE

This international phase III, randomized, placebo-controlled, double-blind study assessed the efficacy and safety of lenalidomide in RBC transfusion-dependent patients with International Prognostic Scoring System lower-risk non-del(5q) myelodysplastic syndromes ineligible for or refractory to erythropoiesis-stimulating agents.

PATIENTS AND METHODS

In total, 239 patients were randomly assigned (2:1) to treatment with lenalidomide (n = 160) or placebo (n = 79) once per day (on 28-day cycles). The primary end point was the rate of RBC transfusion independence (TI) ≥ 8 weeks. Secondary end points were RBC-TI ≥ 24 weeks, duration of RBC-TI, erythroid response, health-related quality of life (HRQoL), and safety.

RESULTS

RBC-TI ≥ 8 weeks was achieved in 26.9% and 2.5% of patients in the lenalidomide and placebo groups, respectively (P < .001). Ninety percent of patients achieving RBC-TI responded within 16 weeks of treatment. Median duration of RBC-TI with lenalidomide was 30.9 weeks (95% CI, 20.7 to 59.1). Transfusion reduction of ≥ 4 units packed RBCs, on the basis of a 112-day assessment, was 21.8% in the lenalidomide group and 0% in the placebo group. Higher response rates were observed in patients with lower baseline endogenous erythropoietin ≤ 500 mU/mL (34.0% v 15.5% for > 500 mU/mL). At week 12, mean changes in HRQoL scores from baseline did not differ significantly between treatment groups, which suggests that lenalidomide did not adversely affect HRQoL. Achievement of RBC-TI ≥ 8 weeks was associated with significant improvements in HRQoL (P < .01). The most common treatment-emergent adverse events were neutropenia and thrombocytopenia.

CONCLUSION

Lenalidomide yields sustained RBC-TI in 26.9% of RBC transfusion-dependent patients with lower-risk non-del(5q) myelodysplastic syndromes ineligible for or refractory to erythropoiesis-stimulating agents. Response to lenalidomide was associated with improved HRQoL. Treatment-emergent adverse event data were consistent with the known safety profile of lenalidomide.

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.

A cost-effectiveness analysis of using azacitidine vs. decitabine in treating patients with myelodysplastic syndromes

OBJECTIVE

Azacitidine and decitabine are used to treat patients with myelodysplastic syndromes (MDS) in the United States (US). This study sought to assess their relative cost-effectiveness.

DESIGN AND METHODS

The authors developed a cost-effectiveness Markov model (1-month cycles) tracking hypothetical cohorts of MDS patients treated with azacitidine or decitabine over 2 years. The model used a US payer perspective and 2009 costs. Health states modeled included MDS with Transfusion Dependence, MDS with Transfusion Independence, Progression to Acute Myelogenous Leukemia (AML), and Death. Incremental cost-effectiveness outcomes included cost per quality-adjusted life year (QALY), cost per life year (LY), cost per patient-month of transfusion independence, and cost per case of AML progression avoided. One-way sensitivity analyses were performed on key model parameters.

RESULTS

Compared to decitabine, azacitidine was associated with better survival (1.512 LYs vs 1.292), more QALYs gained (1.041 vs 0.870), more patient-months with transfusion independence (8.328 vs 6.224), and a greater proportion of patients avoiding progression to AML (50.9% vs 28.5%). Total per-patient costs over 2 years for azacitidine were lower than for decitabine ($150,322 vs $166, 212).

LIMITATIONS

To inform and update the model over time, it will be important that randomized or observational clinical studies be conducted to directly compare azacitidine and decitabine, provide new information on how these medicines are used, and on their relative clinical effectiveness.

CONCLUSION

Results demonstrate that azacitidine provides greater clinical benefit and costs less than decitabine across all key outcomes. These results accentuate the positive role of azacitidine in providing cost-effective care for MDS.

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.

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.

Azacitidine prolongs overall survival compared with conventional care regimens in elderly patients with low bone marrow blast count acute myeloid leukemia

PURPOSE

In a phase III randomized trial, azacitidine significantly prolonged overall survival (OS) compared with conventional care regimens (CCRs) in patients with intermediate-2- and high-risk myelodysplastic syndromes. Approximately one third of these patients were classified as having acute myeloid leukemia (AML) under current WHO criteria. This analysis compared the effects of azacitidine versus CCR on OS in this subgroup.

PATIENTS AND METHODS

Patients were randomly assigned to receive subcutaneous azacitidine 75 mg/m(2)/d or CCR (best supportive care [BSC] only, low-dose cytarabine (LDAC), or intensive chemotherapy [IC]).

RESULTS

Of the 113 elderly patients (median age, 70 years) randomly assigned to receive azacitidine (n = 55) or CCR (n = 58; 47% BSC, 34% LDAC, 19% IC), 86% were considered unfit for IC. At a median follow-up of 20.1 months, median OS for azacitidine-treated patients was 24.5 months compared with 16.0 months for CCR-treated patients (hazard ratio = 0.47; 95% CI, 0.28 to 0.79; P = .005), and 2-year OS rates were 50% and 16%, respectively (P = .001). Two-year OS rates were higher with azacitidine versus CCR in patients considered unfit for IC (P = .0003). Azacitidine was associated with fewer total days in hospital (P < .0001) than CCR.

CONCLUSION

In older adult patients with low marrow blast count (20% to 30%) WHO-defined AML, azacitidine significantly prolongs OS and significantly improves several patient morbidity measures compared with CCR.

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.

Azacitidine prolongs overall survival and reduces infections and hospitalizations in patients with WHO-defined acute myeloid leukaemia compared with conventional care regimens: an update

Azacitidine (AZA), as demonstrated in the phase III trial (AZA-001), is the first MDS treatment to significantly prolong overall survival (OS) in higher risk MDS pts ((2007) Blood110 817). Approximately, one-third of the patients (pts) enrolled in AZA-001 were FAB RAEB-T (≥20–30% blasts) and now meet the WHO criteria for acute myeloid leukaemia (AML) ((1999) Blood17 3835). Considering the poor prognosis (median survival <1 year) and the poor response to chemotherapy in these pts, this sub-group analysis evaluated the effects of AZA versus conventional care regimens (CCR) on OS and on response rates in pts with WHO AML.

The effects of continued azacitidine treatment cycles on response in higher risk patients with myelodysplastic syndromes: an update

The international, phase III, multi-centre AZA-001 trial demonstrated azacitidine (AZA) is the first treatment to significantly extend overall survival (OS) in higher risk myelodysplastic syndromes (MDS) patients (Fenaux (2007) Blood110 817). The current treatment paradigm, which is based on a relationship between complete remission (CR) and survival, is increasingly being questioned (Cheson (2006) Blood108 419). Results of AZA-001 show CR is sufficient but not necessary to prolong OS (List (2008) Clin Oncol26 7006). Indeed, the AZA CR rate in AZA-001 was modest (17%), while partial remission (PR, 12%) and haematological improvement (HI, 49%) were also predictive of prolonged survival. This analysis was conducted to assess the median number of AZA treatment cycles associated with achievement of first response, as measured by IWG 2000-defined CR, PR or HI (major + minor). The number of treatment cycles from first response to best response was also measured.

Tolerability and hematologic improvement assessed using three alternative dosing schedules of azacitidine in patients with myelodysplastic syndromes

7083

Background: At a dosing schedule of 75 mg/m2/day SC for 7 days every 4 weeks, azacitidine is an effective and safe treatment (Tx) for patients (pts) with myelodysplastic syndromes (MDS) (JCO 2002; 20:2429). An alternative dosing schedule that eliminates the need for weekend dosing would be more convenient to pts and clinicians. Methods: In this phase II, multicenter, open-label trial, pts with MDS were randomized to 1 of 3 regimens that were repeated every 4 weeks: AZA 5–2-2 (75 mg/m2/day × 5 days, followed by 2 days no Tx, followed by 75 mg/m2/day × 2 days), AZA 5–2-5 (50 mg/m2/day × 5 days, followed by 2 days no Tx, followed by 50 mg/m2/day × 5 days) or AZA 5 (75 mg/m2/day × 5 days). To determine if response/improvement according to International Working Group criteria (Blood 2000; 96:3671) can be maintained after 6 cycles, the study was amended to include a 12-month maintenance comparing AZA 5 every 4 weeks with AZA 5 every 6 weeks. Results: As of Nov. 30, 2006, 138 pts have been randomized to AZA 5–2-2 (n=46), AZA 5–2-5 (n=47) and AZA 5 (n=45). Most pts are RA (43%) or RAEB (30%), based on FAB classification. Of 104 pts who have received =2 cycles of Tx, hematologic improvement (major or minor in at least 1 cell line) occurred in 63% (65) of the patients ( Table ). Of these pts, 14% had a bi-lineage (AZA 5–2-2: 11%, AZA 5–2-5: 10%, AZA 5: 22%) and 6% had a tri-lineage AZA 5–2-2: 6%, AZA 5–2-5: 7%, AZA 5: 5%) response (based on any improvement). Ongoing pts in the study include AZA 5–2-2: 41% (19/46), AZA 5–2-5: 47% (22/47), and AZA 5: 58% (26/45). No treatment-related mortality has been reported. Most Tx-related grade 3 or 4 events were hematological (AZA 5–2-2: 39%, AZA 5–2-5: 24%, AZA 5: 16%). Updated data, including several pts who have completed at least 6 cycles maintenance, will be available at the time of the meeting. Conclusions: These data indicate that the 3 alternative azacitidine dosing schedules are safe, effective, and similar in efficacy with the FDA-approved regimen.

[Table: see text] [Table: see text]

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.

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/m(2) SC dose, or treatment B, consisting of azacitidine administered as a single 75-mg/m(2) 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/m(2), was generally well tolerated.

Feasibility of using recipients of health promotional newsletters for post-marketing surveillance

Achieving an adequate sample size is one of the major difficulties in performing post-marketing observational studies of health outcomes in persons taking specific drug preparations. We assessed the feasibility of recruiting participants for such a study of Cardizem CD from approximately 400,000 U.S. recipients of a health promotion newsletter. A three-page questionnaire was sent to a 2.5% random sample (n = 10,000) of recipients, stratified by geographic region. After two mailings, 2779 (28%) returned the questionnaire. Of the 2779 respondents, 2132 (77%) reported having high blood pressure. Eighty-seven percent indicated a willingness to participate in a long-term prospective study. In a multivariate model, calcium channel blocker (CCB) use was associated with a history of coronary heart disease, duration of hypertension medication use greater than 1 year, a rating of good or excellent hypertension care, higher systolic blood pressure, higher education level, family history of cardiovascular disease, and history of smoking. These results indicate that self-reported CCB users may be at greater risk of cardiovascular heart disease and that it is feasible to use health promotion newsletters as a source of participants in prospective studies of cardiovascular disease.

Long-acting diltiazem CD is safe and effective in a hypertensive Mexican-American population

STUDY OBJECTIVE

To evaluate the safety and effectiveness of diltiazem CD for reducing blood pressure in Mexican-American patients with mild to moderate hypertension.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

Twelve clinical sites in the United States.

PATIENTS

Patients with baseline diastolic blood pressures between 95 and 115 mm Hg.

INTERVENTIONS

Patients were treated with an average daily dose of diltiazem CD 246 mg (60 patients) or placebo (58 patients) to achieve a trough diastolic blood pressure below 90 mm Hg.

MEASUREMENTS AND MAIN RESULTS

Diltiazem CD significantly reduced mean diastolic blood pressure compared with placebo, -8.2 versus -4.1 mm Hg, respectively (p=0.0025). Diastolic blood pressure below 90 mm Hg or a reduction of 10 mm Hg or more was achieved by 57% of diltiazem CD versus 28% of placebo recipients. Systolic blood pressure and heart rate were also reduced with diltiazem CD. Adverse events were mild, with similar frequency for diltiazem CD (15%) and placebo (19%).

CONCLUSION

Diltiazem CD is safe and effective in hypertensive Mexican-Americans, and diastolic blood pressure reductions compare with those in non-Hispanic white patients.

Antianginal response to once-daily diltiazem CD in patients receiving concomitant beta-blockers, long-acting nitrates, or both. Diltiazem CD Study Group

STUDY OBJECTIVE

To determine the safety and efficacy of diltiazem CD 180 mg administered once/day in patients with chronic stable angina inadequately controlled with P-blockers, long-acting nitrates, or both.

DESIGN

Multicenter, randomized, double-blind, placebo-controlled, parallel-group trial.

SETTING

Medical clinics in the private and academic sectors.

PATIENTS

Of 172 patients, 170 completed the 2-week double-blind treatment period.

INTERVENTION

. Patients received either diltiazem CD 180 mg or placebo once/day in combination with existing antianginal therapy.

MEASUREMENTS AND MAIN RESULTS

The time to termination of exercise tolerance testing, 24 hours after the dose increased significantly in the diltiazem CD group (37.2 sec) compared with the placebo group (21.3 sec, p=0.0438). Time to onset of angina during exercise testing also increased (57.6 vs 35.0 sec, respectively, p=0.0324), as did time to moderate angina (37.5 vs 20.6 sec, respectively, p=0.0354). The rates of total angina attacks and of angina attacks on exertion were significantly reduced in the diltiazem CD group versus placebo (p<0.05). Significant reductions in systolic and diastolic blood pressures and heart rate-blood pressure product measured at rest, submaximum exercise, and exercise termination were observed in diltiazem CD-treated patients compared with placebo (p<0.05). The frequency of treatment-related adverse events was identical in the two groups, 15.1%.

CONCLUSION

Diltiazem CD 180 mg once/day is an effective, safe, and beneficial initial dosage when added to existing antianginal therapy.

Control of heart rate during transition from intravenous to oral diltiazem in atrial fibrillation or flutter

We tested whether patients presenting with atrial fibrillation (AF) or flutter (AFl) with a rapid ventricular response could maintain control of heart rate while transferring from a bolus and continuous infusion of intravenous diltiazem to oral diltiazem. Forty patients with AF or AFI and sustained ventricular rate > or = 120 beats/min received intravenous diltiazem "bolus" (20 to 25 mg for 2 minutes) and "infusion" (5 to 15 mg/hour for 6 to 20 hours). Oral long-acting diltiazem (diltiazem CD 180, 300, or 360 mg/24 hours) was administered in patients in whom stable heart rate control was attained during constant infusion. Intravenous diltiazem infusion was discontinued 4 hours after the first oral dose, and patients were monitored during 48 subsequent hours of "transition" to oral therapy. Response to diltiazem was defined as heart rate <100 beats/min, > or = 20% decrease in heart rate from baseline, or conversion to sinus rhythm. Other rate control or antiarrhythmic medications were not allowed during the study period. Thirty-seven of 40 patients maintained heart rate control during the bolus, and 35 of the remaining 37 maintained control during the infusion of intravenous diltiazem. Of the 35 patients achieving heart rate control with intravenous diltiazem who entered the transition to oral therapy, 27 maintained heart rate control (response rate of 77%/, 95% confidence interval 63% to 91%). The median infusion rate of intravenous diltiazem was 10 mg/hour, and the median dose of oral diltiazem CD was 300 mg/day. Oral long-acting diltiazem was 77% effective in controlling ventricular response over 48 hours in patients with AF or AFl in whom ventricular response was initially controlled with intravenous diltiazem.

Dose-response evaluation of once-daily therapy with a new formulation of diltiazem for stable angina pectoris. Diltiazem CD Study Group

Diltiazem hydrochloride in a once-daily capsule formulation (DCD) has recently been approved in the United States for the treatment of mild to moderate hypertension and chronic stable angina pectoris. This trial evaluated the dose response of DCD in patients with chronic stable angina pectoris. In a multicenter, randomized, double-blind, parallel-design trial, the effects and tolerability of once-daily therapy with placebo or DCD (60, 120, 240, 360, or 480 mg) were evaluated 24 hours after dosing, following 3 weeks of therapy in 227 patients with reproducible stable exertional angina pectoris. A significant linear dose trend (p = 0.004) was present across the 6 treatment groups for the primary end point--time to exercise termination at 24 hours after dosing--using a standard Bruce treadmill exercise test. A significant linear dose trend was also seen for time to 1 mm ST-segment depression at 24 hours after dosing. Similar effects on exercise parameters were also seen at 4 hours after dosing. A linear dose trend (p = 0.04) was noted relative to the overall anginal attacks during daily activities and for anginal attacks during exercise (p = 0.02). Overall frequency of treatment-related adverse effects was dose-related and occurred in 24.4% and 17.5% of patients treated with DCD and placebo, respectively. At a dose up to 240 mg/day, improvement in exercise tolerance was achieved without an associated increase in the rate of treatment-related adverse events compared with placebo.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of betaxolol in the treatment of stable exertional angina pectoris: a dose-ranging study

To assess the efficacy of oral betaxolol in the treatment of stable exertional angina pectoris and to determine the relationship between betaxolol doses/serum concentrations and clinical/hemodynamic responses the authors studied 24 patients prior to and following stepwise administration of 5, 10, 20, 40, and 80 mg doses. The major endpoint for the study was the achievement of clinical beta blockade (heart rate 50-60 beats/min and less than or equal to 20% rise in treadmill stage I heart rate). Betaxolol produced a decrease in mean angina pectoris frequency from 6.6 +/- 1.9 episodes/week with placebo to 0.2 +/- 0.5 episode/week during clinical beta blockade (p less than 0.00005). Mean treadmill exercise time increased from 3.1 +/- 1.7 min with placebo to 7.3 +/- 2.3 min with doses sufficient to reduce angina pectoris frequency greater than or equal to 75% (p less than 0.00005) and to 8.0 +/- 2.3 min during clinical beta blockade (p less than 0.00005). The mean doses of betaxolol required to produce a greater than or equal to 75% decrease in angina pectoris frequency and clinical beta blockade were 12 +/- 5 mg (range 5-40 mg) and 28 +/- 29 mg (range 5-80 mg) respectively. Mean serum concentrations associated with these clinical endpoints were 23.8 +/- 9.7 ng/mL and 59.7 +/- 54.0 ng/mL respectively. The results indicate that betaxolol, in widely ranging doses, is highly effective in reducing angina pectoris frequency and improving exercise capacity in patients with stable exertional angina pectoris.