Single-dose IV ferric derisomaltose improves hematologic and patient-reported outcomes in pregnant individuals with iron deficiency anemia

Abstract Background: Iron deficiency anemia (IDA) affects over 40% of pregnancies worldwide and is associated with fatigue, reduced quality of life, and increased risk of postpartum hemorrhage. Oral iron is the standard treatment for IDA but is often associated with side effects leading to poor adherence. Intravenous (IV) iron is more effective but is only used after the first trimester and its impact on hematologic outcomes in pregnancy are not well studied. Ferric derisomaltose (FDI) is a newer single-dose IV preparation but has limited data in pregnancy. We conducted the first trial in the United States of FDI in pregnancy to evaluate the safety and efficacy of a 1,000 mg dose of IV FDI in pregnant individuals with IDA. The primary outcomes were efficacy and infusion-related safety. Secondary outcomes included hematologic response, patient-reported fatigue and mood, and maternal and neonatal clinical outcomes. Methods: This is a prospective, single-arm clinical trial conducted from January 2024 to July 2025 (NCT05763043). Pregnant individuals with IDA and either intolerance to oral iron or >28 weeks' gestation received a single 1,000 mg dose of IV FDI over ~20 minutes without premedication. Eligible participants were ≥18 years old, in the second or third trimester (14–42 weeks), and with hemoglobin (Hb) <11 g/dL and ferritin <50 μg/L. Key exclusion criteria included prior IV iron hypersensitivity, active infection, systemic inflammatory conditions, or malignancy. Hematologic outcomes were assessed at baseline, delivery, and at 6 weeks postpartum, with the primary efficacy outcome defined as mean Hb increase at 6 weeks postpartum. Patient-reported outcomes (PROMIS Fatigue, FACIT-Fatigue, and EPDS) and maternal and neonatal clinical outcomes (e.g., transfusion, delivery mode, birthweight, Apgar scores, neonatal intensive care unit [NICU] admission, and cord blood iron indices) were evaluated prospectively. Results: A total of 75 pregnant individuals received a single 1,000 mg dose of IV FDI. The average age of participants was 32 years with a mean estimated gestational age at infusion of 32 weeks. The primary efficacy outcome 6 weeks Hb mean increased from 10.3 ± 0.6 g/dL at baseline to 12.9 ± 0.9 g/dL at 6 weeks postpartum (p < 0.001) and 64.3% of participants achieved a ≥1 g/dL Hb increase prior to delivery. Secondary efficacy markers also improved significantly at 6 weeks postpartum—ferritin increased from baseline 11.9 ± 6.7 to 106.8 ± 51.7 µg/L (p < 0.001), and transferrin saturation rose from baseline 12.2 ± 9.7% to 28.5 ± 11.5% (p < 0.001). We observed significant improvement in patient-reported outcomes (n=67): PROMIS Fatigue T-scores decreased from 61.8 ± 7.5 to 51.7 ± 8.1 (p < 0.001) and Edinburgh Postnatal Depression Scale (EPDS) scores improved from 9.2 ± 5.8 to 6.8 ± 5.7 (p = 0.003), reflecting reduced maternal fatigue and depressive symptoms. IV FDI was well-tolerated, with an average infusion time of <24 minutes. No grade 3–4 infusion reactions or serious adverse events requiring medical intervention or hospitalization were reported. Conclusion: In pregnant individuals with IDA, a single 1,000 mg dose of IV FDI was well-tolerated and significantly improved maternal Hb, iron stores, and fatigue. These results demonstrate improved hematologic parameters and patient-reported outcomes, supporting the safety and efficacy of FDI in pregnancy. FDI represents a viable alternative to oral iron supplementation, particularly for patients with intolerance or more severe anemia. Future studies are needed to further the impact of IV iron therapy on maternal and neonatal clinical outcomes, including postpartum hemorrhage and transfusion requirements.