Modeling of treatment response to erythropoiesis-stimulating agents in older (age≥70years) and younger (age<70years) patients with cancer and anemia: findings from the Anemia Cancer Treatment study

INTRODUCTION

The Anemia Cancer Treatment study assessed hemoglobin (Hb) outcomes following treatment with erythropoiesis-stimulating agents (ESA) in anemic (Hb≤11g/dL) patients in Europe. We replicated the original analyses stratifying by age, namely patients aged ≥70 (n=637) versus those aged<70 (n=1555).

MATERIALS AND METHODS

A secondary analysis of Hb outcomes was assessed over 8-10weeks. Treatment response criteria included increases of Hb≥1g/dL, Hb≥1g/dL over 8weeks, and Hb≥2g/dL over the course of the study period.

RESULTS

Mean Hb increased from similar levels of 9.5g/dL [p=not significant (ns)] at visit one to 10.9g/dL (p=ns) at visit three (both p<0.001). Patients aged≥70 had higher mean Hb at visit two (10.6g/dL vs. 10.3g/dL, p<0.001). Cohorts did not differ in treatment response rates (all p=ns). Mean performance status differed between cohorts at each visit (all p≤0.011); both groups showed significant improvements (both p<0.001). Immediacy of response was a consistent determinant but was more pronounced among patients aged≥70. Less consistent determinants included performance status in the age≥70 group, as well as hematological malignancy and Hb at ESA start in the age<70 group. The proportion of variance in Hb outcomes attributable to treatment center ranged from 0.090 to 0.289 in the age≥70 cohort and 0.126 to 0.361 in the age<70 cohort.

CONCLUSIONS

Both groups achieved similar Hb levels with the age≥70 cohort showing a higher initial evolution rate and potentially a different Hb response trajectory. Patients age≥70 were more likely to benefit from ESAs if showing an early erythropoietic response and exhibiting no or little impairment in performance status. Differential attribution of variability in older vs. younger adults suggests that individualization of ESA therapy may facilitate Hb response in geriatric patients with cancer.

Chemotherapy-induced anemia: the story of darbepoetin alfa

BACKGROUND

Prior to the approval of the first erythropoiesis-stimulating agent (ESA) in the early 1990s, red blood cell transfusions were the primary means of treating severe chemotherapy-induced anemia (CIA), with little recourse for those with more mild forms of the condition. The introduction of the ESAs allowed treatment of mild-to-moderate CIA in patients with cancer. It has been a decade since darbepoetin alfa (DA), a second-generation ESA with a longer half-life, became available to patients with CIA.

OBJECTIVE AND METHODS

We present a review of studies on DA in CIA, from its development through to the present day. Medline was searched for randomized clinical trials on DA. Additional trials and meta-analyses on ESAs were incorporated into this review when relevant.

RESULTS

The first publications on DA generally focused on optimal dosing, efficacy and tolerability. In these, it was shown that DA is an effective and well tolerated treatment option to achieve hematopoietic response, regardless of dosing interval. Subsequently, the focus shifted towards meta-analyses on survival data of all ESAs. These reported conflicting results regarding mortality and/or disease progression. However, guidelines for ESA use were updated and, when followed, these make ESAs a well tolerated and effective tool for managing CIA.

CONCLUSIONS

As the past decade has broadened our knowledge on the benefits and risks of CIA management, continued high-quality studies will help to optimize treatment with ESAs in order to maximize quality of life for these patients. The limitation of a literature review of this nature is the complete reliance on previously published research and the availability of these studies using the methodology outlined above.

Intravenous iron supplementation for the treatment of chemotherapy-induced anaemia - systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Current guidelines are inconclusive regarding intravenous (IV) iron for treatment of chemotherapy-induced anaemia (CIA).

MATERIAL AND METHODS

Systematic review and meta-analysis of randomised controlled trials comparing IV iron with no iron or oral iron for treatment of chemotherapy induced anaemia (CIA).

PRIMARY OUTCOMES

haematopoietic response and red blood cell (RBC) transfusion requirements. For dichotomous data, relative risks (RR) with 95% confidence intervals (CIs) were estimated and pooled. For continuous data, weighted mean differences were calculated.

RESULTS

Eleven trials included 1681 patients, the majority examining the addition of IV iron to erythropoiesis stimulating agents (ESA) (1562 patients, 92.9%). IV iron significantly increased haematopoietic response rate [RR 1.28 (95% CI 1.125-1.45), seven trials with ESA] and decreased the rate of blood transfusions both in trials with ESA [RR 0.76 (95% CI 0.61-0.95), seven trials] and without ESA [RR 0.52 (95% CI 0.34-0.80)]. The increase in haematopoietic response rate correlated with total IV iron dose, regardless of baseline iron status. Mortality and safety profile was comparable between groups.

CONCLUSIONS

IV iron added to ESA results in an increase in haematopoietic response and reduction in the need for RBC transfusions, with no difference in mortality or adverse events.

Darbepoetin alfa in the treatment of anemia in cancer patients undergoing chemotherapy

For years, the treatment of chemotherapy-induced anemia (CIA) consisted of red blood cell transfusions. Major disadvantages of transfusions are their temporary effect and limitation to treatment of severe anemia. In an extensive clinical trial program in patients with CIA, darbepoetin alfa (DA) - a long-acting recombinant human erythropoietin - was proven to be very effective in reducing transfusion needs in patients developing CIA. The administration is suitable with most chemotherapy schemes. Caution is needed in patients with a history of thrombo-embolic events, as a slightly higher incidence of these events is noted in patients treated with darbepoetin alfa or erythropoietin substitution agents (ESAs) in general. In recent years, concerns have been raised about a potential negative influence of these agents on survival. In this respect, it is important to make the distinction between studies on the treatment of existing CIA versus treatment with ESAs outside this indication. On the other hand, it has always been assumed that transfusions were a completely safe treatment, but concerns about a potential negative effect on survival have been raised for transfusions as well. The safety concerns with DA and ESAs in general led to a pharmacovigilance program and an adaptation of the guidelines for treatment of CIA, focusing on treatment of moderate CIA but no longer on mild CIA. Now that the most recent safety data of the pharmacovigilance program of ESAs is almost completed, the clinical impact of the shift to the treatment of only moderate anemia is discussed in this review, which provides a critical view on the indications of DA and the benefit-risk assessment, in order to provide good supportive care without harm to the patient.