Ferric carboxymaltose fends off anaemia in kids with CKD

Intravenous administration of ferric carboxymaltose (FCM) helps improve haemoglobin and iron levels in children suffering from chronic kidney disease (CKD), according to a recent study.

Seventy-nine paediatric CKD patients (median age 9 years, 40.5 percent girls) participated in the study, in whom laboratory parameters were evaluated 15–45 days after FCM infusion. Fifty-eight participants had available haemoglobin data, of whom 70.7 percent (n=41) were deemed to have anaemia at baseline. [Front Pediatr 2022;doi:10.3389/fped.2022.967233]

The remaining patients had adequate haemoglobin concentrations, but their serum iron deposits were low, with transferrin saturation (TS) value ≤20 percent and/or ferritin ≤100 ng/mL.

Most patients demonstrated positive responses to FCM infusion. Median haemoglobin increased from 10.4 g/dL at baseline to 11.8 g/dL after infusion. Though the median improvement was only 1.4 g/dL, this could be due to the short follow-up duration of 1 month.

“We cannot exclude that a longer examination time of the study could have demonstrated a better response,” the researchers said.

Similar improvements were seen when participants were categorized into those who were (10.4 to 11.4 g/dL) and were not (11.4 to 12.6 g/dL) taking erythropoiesis-stimulating factors.

Aside from haemoglobin, FCM infusion led to a large increase in ferritin levels, jumping from a median of 32.0 ng/mL at baseline to 285 ng/mL at the 30-day follow-up. TS likewise saw great improvements, increasing from 11 percent to 31 percent 1 month after infusion. The same was true for serum iron levels (28 to 66 µg/dL).

FCM infusion was also well-tolerated. No serious hypersensitivity reactions were detected, and no anaphylactic effects emerged. Median serum phosphate was 4.9 mg/dL at baseline, which dropped by a median of 0.5 mg/dL post-transfusion in 22 patients. Blood phosphate remained in normal range.

One adverse event was reported, arising in a 16-year-old patient. Extravasation occurred at the end of infusion and was treated with Burow’s solution combined with local cold application and limb elevation. The affected site at the anterior forearm showed painless discoloration, which improved partially.

A more stable complex

“Although oral iron is considered the treatment of choice in paediatric patients due to its noninvasiveness and lower cost, it is often poorly tolerated,” the researchers said.

Common side effects include nausea, constipation, and abdominal pain, all of which negatively impact the adherence to oral iron medication. Children on haemodialysis are also ineligible for this treatment.

Moreover, oral iron is often poorly absorbed by patients and can sometime take weeks to have demonstrable impacts on haemoglobin levels. [Kidney Int 2012;Supp 2:279-335]

“Because the FCM is a stable complex, this allows a maximum cumulative weekly dose of 1,000 mg of iron to be administered, and fewer infusions are needed to administer the total iron dosage needed for each patient, compared with other formulations such as iron sucrose,” the researchers said, adding that the intravenous route of administration also helps avoid gastrointestinal side effects.

While the present analysis suggests that FCM is a promising alternative to oral iron therapy in children with CKD, it is limited by its observational and retrospective nature. Future studies are needed to verify these findings.