What dose of Monoferric (ferric derisomaltose) is required for an 84-year-old male with severe iron deficiency anemia?

Monoferric (Ferric Derisomaltose) Dosing for Severe Iron Deficiency Anemia

For an 84-year-old male with severe iron deficiency anemia (iron 3, ferritin 22, Hb 85 g/L), a single 1000 mg dose of Monoferric (ferric derisomaltose) is required for complete iron repletion.

Rationale for Single Dose Approach

The patient presents with clear laboratory evidence of severe iron deficiency anemia:

• Hemoglobin: 85 g/L (severe anemia)
• Ferritin: 22 ng/mL (significantly below 30 ng/mL threshold)
• Iron: 3 (severely depleted)

These values indicate absolute iron deficiency requiring prompt correction. Based on current guidelines:

• The European Society for Clinical Nutrition and Metabolism recommends a single IV dose of whole-body iron replacement using 1 g of iron provided as a large single dose over 15 minutes using one of the recent carbohydrate products for iron deficiency correction 1
• Monoferric (ferric derisomaltose) is specifically designed for single-dose administration of 1000 mg, which is sufficient for most adults weighing >50kg 2

Administration Details

• Monoferric should be administered as a single 1000 mg intravenous infusion over 15 minutes 2
• No test dose is required as the risk of severe hypersensitivity reactions is very low with this formulation 3
• The single-dose approach eliminates the need for multiple clinic visits and ensures complete iron repletion 4

Advantages of Ferric Derisomaltose for This Patient

1. Age-appropriate: At 84 years old, the patient will benefit from fewer clinic visits required with single-dose therapy
2. Efficacy: Ferric derisomaltose has demonstrated faster hematological response compared to multiple-dose iron sucrose regimens 5
3. Safety profile: The FERWON-NEPHRO trial showed that ferric derisomaltose has a favorable cardiovascular safety profile, which is important in elderly patients 5

Expected Response

• Hemoglobin should increase by approximately 2 g/dL within 4 weeks of treatment 6
• Complete normalization of hemoglobin may take up to 8 weeks 1
• Ferritin levels should be normalized within 8-10 weeks 1

Monitoring Recommendations

• Check complete blood count and iron studies (ferritin, transferrin saturation) at 8-10 weeks post-infusion 6
• Do not check ferritin levels earlier than 8 weeks after iron infusion as they will be falsely elevated 1
• After normalization, monitor every 3 months for one year, then annually 6

Potential Pitfalls to Avoid

1. Underdosing: Using multiple smaller doses (like iron sucrose 200 mg) would require multiple visits and may delay hemoglobin recovery
2. Delayed follow-up: Failing to monitor response could miss persistent anemia
3. Missing underlying cause: Ensure investigation of the cause of iron deficiency anemia in this elderly patient, as gastrointestinal malignancy must be ruled out 6

In summary, a single 1000 mg dose of Monoferric is the optimal approach for this elderly patient with severe iron deficiency anemia, providing complete iron repletion with minimal clinic visits and a favorable safety profile.