Darbepoetin alfa for treating chemotherapy-induced anemia in patients with a baseline hemoglobin level < 10 g/dL versus ≥10 g/dL: an exploratory analysis from a randomized, double-blind, active-controlled trial

<p>Abstract</p> <p>Background</p> <p>Several studies have shown that darbepoetin alfa, an erythropoiesis-stimulating agent (ESA), can reduce transfusions and increase hemoglobin (Hb) levels in patients with chemotherapy-induced anemia (CIA). Recent safety concerns, however, have prompted changes to ESA product information. In the European Union and United States, ESA therapy initiation for CIA is now recommended at a Hb level ≤10 g/dL. The present exploratory analysis examined how ESA initiation at this Hb level may impact patient care.</p> <p>Methods</p> <p>Data from a phase 3 randomized trial were retrospectively reanalyzed. CIA patients with nonmyeloid malignancies were randomized 1:1 to 500 mcg darbepoetin alfa every three weeks (Q3W) or 2.25 mcg/kg darbepoetin alfa weekly (QW) for 15 weeks. A previously published report from this trial showed Q3W dosing was non-inferior to QW dosing for reducing transfusions from week 5 to end-of-the-treatment period (EOTP). In the present analysis, outcomes were reanalyzed by baseline Hb <10 g/dL and ≥10 g/dL. Endpoints included transfusion rates, Hb outcomes, and safety profiles.</p> <p>Results</p> <p>This study reanalyzed 351 and 354 patients who initiated ESA therapy at a baseline Hb of <10 g/dL or ≥10 g/dL, respectively. From week 5 to EOTP, the estimated Kaplan-Meier transfusion incidence (Q3W vs QW) was lower in the ≥10 g/dL baseline-Hb group (14% vs 21%) compared with the <10 g/dL baseline-Hb group (36% vs 41%). By week 5, the ≥10 g/dL baseline-Hb group, but not the <10 g/dL baseline-Hb group, achieved a mean Hb ≥11 g/dL. The Kaplan-Meier estimate of percentage of patients (Q3W vs QW) who achieved Hb ≥11 g/dL from week 1 to EOTP was 90% vs 85% in the ≥10 g/dL baseline-Hb group and 54% vs 57% in the <10 g/dL baseline-Hb group. Both baseline-Hb groups maintained mean Hb levels <12 g/dL and had similar safety profiles, though more patients in the ≥10 g/dL baseline-Hb group reached the threshold Hb of ≥13 g/dL.</p> <p>Conclusion</p> <p>In this exploratory analysis, darbepoetin alfa Q3W and QW raised Hb levels and maintained mean Hb at <12 g/dL in both baseline-Hb groups. The ≥10 g/dL baseline-Hb group had fewer transfusions and faster anemia correction. Additional studies should prospectively evaluate the relationship between Hb levels at ESA initiation and outcomes.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov Identifier NCT00118638.</p

Clinical impact of epoetins in the treatment of anemia with special emphasis on patients with lymphoid malignancies. : dosing, iron supplementation and safety

The aim of this thesis was to determine the relevant dose of arbepoetin-alfa (DA) in patients with lymphoproliferative diseases (LPD) and chemotherapy induced anemia (CIA), to study the clinical impact of intravenous (IV) iron supplementation combined with epoetin beta treatment, to identify factors that might predict hemoglobin (Hb) response to treatment with epoetins and to investigate safety of DA. A dose-finding phase II study was able to assess a reasonable DA dose of 2.25 μg/kg once weekly for the treatment of CIA in patients with LPD. Dose-response trends were observed for the different dose cohorts although not statistically significant for any of the endpoints. However a significantly higher proportion of patients achieved Hb response (increase ≥2 g/dL) in the combined DA groups than in placebo (P<0.001). A larger pivotal phase II trial was performed in a similar setting o confirm that the dose 2.25μg/kg once weekly was appropriate and safe. The proportion of patients achieving Hb response was significantly higher in the DA group (60%) than in the placebo group (18%) (P<0,001) and resulted in higher mean changes in Hb than placebo from baseline, 2.66 g/dl versus 0.69 /dl. Also a significantly lower proportion of patients in the DA group (31%) received RBC tranfusions than in the placebo group (48%). The short-term safety of DA with the tested dose was confirmed. The efficacy of DA was consistent for all end points independent of malignancy type or baseline endogenous erythropoietin serum levels. The correction of moderate anemia in truly iron repleted patients with clinically stable LPD not receiving hemotherapy or RBC transfusions with epoetin beta treatment, with or without IV iron treatment was studied in an open label randomized trial. Also the impact on iron kinetics was assessed. The mean change in Hb concentration from baseline to end of treatment (EOT ) was 2.91 versus 1.50 g/dL respectively (P<0.0001). There was a significant (P<0.0001) difference in mean Hb at EOT between the iron and no-iron groups (13.0 g/dL versus 11.8 g/dL). Hb response was achieved by significantly more patients in the iron group (P=0.0012)than in the no-iron group (93% versus 53%) and the median time to achieve a Hb response was 6 weeks in the iron group compared with 12 weeks in the no-iron group. The mean weekly epoetin dose per patient was statistically significant lower in the iron group at week 13 (P =0.029) and at least 25% lower at EOT. To investigate the long-term safety of DA in cancer patients with CIA four previously published double blind, randomized placebo-controlled phase II -III studies were analysed (n = 1.129). Median durations of progression-free survival and overall survival was comparable between DA and placebo for lung cancer (median follow up 15.8 months), for LPD (median follow up 32.6 months) and in the pooled population (follow up 4 months)