ALBERT

Description: Background: Erythropoiesis-stimulating agents (ESAs) reduce anemia in cancer patients; however, there are concerns that ESAs increase mortality in some patients. Within the framework of an international collaboration we thus conducted a patient-level meta-analysis to assess the effects of ESAs on mortality in cancer patients. Methods: We performed a meta-analysis, based on the intention-to-treat principle, of cancer patients enrolled in randomized controlled trials comparing epoetin alfa, epoetin beta or darbepoetin alfa plus red blood cell transfusions as needed versus transfusion alone, for prophylaxis or treatment of anemia while or after receiving anticancer therapy. Patient-level data were obtained and analyzed by independent statisticians at two academic departments. Primary endpoints were on-study mortality and overall survival in patients receiving chemotherapy, defined as all patients from studies in which =/〉 70% of study population received chemotherapy, and in all cancer patients regardless of anticancer therapy. On-study mortality was defined as death from any cause between date of randomization and 28 days after end of active study phase. Overall survival was defined as death from any cause between date of randomization and longest follow up available. Hazard ratios (HR) and 95% confidence intervals (CIs) were calculated per study and meta-analyzed with fixed-effects and random-effects models. Stratified multivariable Cox-regression analyses were conducted to assess the impact of baseline imbalances. Tests for interactions were used to identify differences in effect across pre-specified subgroups. All analyses were pre-specified in a peer-reviewed protocol (Bohlius et al. 2008). An independent steering committee consisting of clinicians and methodologists agreed on all analyses and interpretations. Independent investigators and representatives from manufacturers contributing data offered advice, but had no decision-making authority. Results: Data from 13,933 cancer patients enrolled in 53 studies were included in the analysis; 38 trials including 10,441 patients used mainly chemotherapy. Including all cancer patients ESAs increased on-study mortality by 17% (HR 1.17; 95% CI 1.06–1.30), with little evidence for a difference between chemotherapy and other trials (p for interaction=0.42), and worsened overall survival by 6% (HR 1.06; 95% CI 1.00–1.12). In the chemotherapy population on-study mortality was increased by 10% (HR 1.10, 95% CI 0.98–1.24) and overall survival was worsened by 4% (HR 1.04; 95% CI 0.97–1.11). Adjusting for known prognostic factors had little effect on the overall estimates. There was no conclusive evidence for effect modification by patient level characteristics such as age, sex, Hb and Hct at baseline, Hb ceiling, type and stage of tumor or study level characteristics (anticancer treatment, ESA treatment schedules, study design and quality) for the outcomes tested. Conclusion: ESA treatment in cancer patients increased on-study mortality by 17% and worsened overall survival by 6%. For patients undergoing chemotherapy the increase was less pronounced, but could not be excluded. In clinical practice, risks of ESAs must be balanced against benefits of ESAs depending on the clinical circumstances of the individual patient.

Description: Background: Erythropoiesis stimulating agents (ESAs) consistently have been shown to decrease transfusions in anemic oncology patients. However, whether they increase mortality in cancer patients is under debate. Results from individual studies conflict, and results from literature based meta-analyses are inconclusive. We conducted a meta-analysis based on individual patient data (IPD) from all available randomized controlled trials (RCTs). Meta-analyses with individual patient data offer several advantages over study-level analysis, including the ability to gain statistical power and increase validity using time-to-event analyses, to adjust for prognostic variables that may have confounded the original treatment comparisons and to investigate subgroups in which treatment may be either more or less effective or harmful. Methods: An international collaboration conducted an individual patent data meta-analysis of ESA effects on mortality in cancer patients. With guidance from an independent steering committee of international experts in hematology, oncology, radiotherapy, epidemiology, medical statistics and a consumer representative, we developed a detailed protocol and statistical analysis plan. Independent RCT investigators and representatives from pharmaceutical companies who submitted data provided additional input through the project’s advisory board. IPD from RCTs of ESA plus red blood cell transfusion (RBCT) (as needed) versus placebo or no ESA plus RBCT (as needed), for prophylaxis or treatment of anemia in cancer patients with or without concurrent antineoplastic therapy, were included. Hazard ratios and 95% confidence intervals (CIs) were calculated per study and meta-analyzed with fixed-effects and random-effects models. Primary endpoints were overall survival (during active study phase and for the longest follow-up available) for patients receiving chemotherapy, and for all cancer patients regardless of anticancer treatment. Stratified multivariable Cox-regression analyses were conducted to assess the impact of baseline imbalances and to identify potential effect modifiers. Duplicate main statistical analyses were conducted independently at two academic statistical departments. Results: Data on 13933 patients enrolled in 53 studies were included in the analysis. Data were provided by the companies Amgen Inc., Johnson & Johnson Pharmaceutical Research & Development, L.L.C., and F. Hoffmann-La Roche Ltd.; and by five independent investigators. Results are currently undergoing internal verification and final evaluation and will be presented at the meeting. Conclusion: Final conclusions will be presented at the meeting. Future analyses using IPD will be conducted to estimate the risks (clots, tumor progression) and potential benefits (transfusion needs and quality of life/fatigue) from other outcomes.