IV iron for chemo-induced anaemia: Ready for primetime?

Intravenous (IV) iron reduces the need for red blood cell (RBC) transfusions in patients with chemotherapy-induced anaemia (CIA), without any difference in adverse events (AEs), compared with oral iron or placebo in a new study.

“IV iron for CIA should then be considered in clinical practice,” commented study author Dr Shira Buchrits from Beilinson Hospital in Israel.  

To assess the impact of IV iron as a monotherapy, Buchrit’s group conducted a meta-analysis of randomized controlled trials (RCTs) that compared IV iron with oral iron or placebo for the treatment of CIA. Excluded were trials that used erythropoiesis-stimulating agents. [J Clin Med 2022;11:4156]

8 RCTs: IV iron, oral iron, or placebo  

Included in the analysis were eight RCTs published between January 1990 and July 2021. Of 1,015 patients, 553 had received IV iron, 271 had taken oral iron, and 191 had not received iron.

The primary outcome was the percentage of patients requiring an RBC transfusion. Secondary outcomes included haematopoietic response (an increase in haemoglobin [Hb] level by >1 g/dL or an increase of >11 g/dL), an absolute Hb concentration or a change from the baseline in the Hb concentration at the end of the trial, the absolute ferritin level and transferrin saturation (TSAT) level at the end of the trial, and adverse events (AEs).

IV administration of iron reduced the risk of an RBC transfusion by 28 percent (95 percent confidence interval [CI], 0.55–0.95) in patients with CIA.

IV iron ups haematopoietic response

For the secondary endpoints, IV iron increased the chance of a haematopoietic response (risk ratio [RR], 1.23, 95 percent CI, 1.01–1.5) and the absolute Hb level or the change from the baseline in Hb at the end of the study (mean difference [MD], 0.23, 95 percent CI, 0.01–0.44).

IV iron was associated with an increase in the ferritin level (MD, 260.65, 95 percent CI 105.79–415.51) but not the low transferrin saturation (TSAT) level (MD, -0.4, 95 percent CI -5.96–5.17). There was no difference in the risk of AEs (RR, 0.97, 95 percent CI, 0.88–1.07) or severe AEs (RR, 1.09, 95 percent CI, 0.76–1.57).  

“The reduction in the need for RBC transfusions is in accordance with current guidelines that recommend a restrictive transfusion strategy, which can minimize risks and may potentially reduce hospital visits,” said Buchrit and team. They added that the increase in haematopoietic response is relevant, as anaemia may be a negative prognostic factor in cancer. 

Not for all, only for FID

“Our meta-analysis supports the use of IV iron for the treatment of CIA,” the authors said. However, the findings mainly apply to patients with functional iron deficiency (FID), defined as a defect in supplying iron to the erythroid marrow despite sufficient iron stores, they added.

Erythroid-stimulating agents (ESAs) are one therapeutic option for the treatment of CIA. However, only 40–70 percent of patients with cancer obtain a haematological response with ESAs.

FID is one of the causes of the absence of an ESA response. To prevent FID, ESAs should be administered with iron support. [Exp Hematol 2007;35(Suppl S1):167-172; J Clin Oncol 2010;28:4996-5010]