New Research Appears to Confirm Injectafer Side Effects Concerns

Published on February 10, 2020 by Sandy Liebhard

Results of two new clinical trials appear to confirm concerns surrounding Injectafer side effects, especially a link to dangerously low phosphorous levels.

Injectafer: Background

Injectafer is an intravenous medication used to treat people suffering from iron-deficiency anemia who can’t tolerate or who haven’t responded well to oral iron supplements.

The U.S. Food & Drug Administration (FDA) approved Injectafer (ferric carboxymaltose) in 2013, after previously rejecting the medication because of a potential association with “excess mortality and severe hypophosphatemia.”

Since then, however, several studies have suggested Injectafer is more likely to cause dangerously low phosphorous levels compared to alternative IV iron treatments. A growing number of Injectafer lawsuits also claim the drug’s manufacturers had long been aware of this risk, but wrongly represented the medication as a safe and effective treatment for iron-deficiency anemia without providing adequate warnings to patients and doctors.

What the Injectafer Study Found

The results of these latest trials were published in the February issue of the Journal of the American Medical Association (JAMA). Together, the studies involved 245 patients with iron-deficiency anemia, all of whom received either 750 mg of Injectafer on day 0 or 1000 mg of Monofer (iron isomaltoside) on days 0 and 7. The patients were followed for 45 days.

• In Trial A (123 patients), hypophosphatemia occurred in just 7.9% of Monofer patients compared to 75% of the Injectafer patients; 
• In Trial B (122 patients), the incidence of hypophosphatemia with use of Monofer was only 8.1%, compared with 7% in Injectafer patients
• In both trials, the prevalence of hypophosphatemia peaked on Day 14 in Injectafer patients and remained significantly higher at Day 35 than in Monofer patients;
• Severe hypophosphatemia (serum phosphorous below 1.0 mg/dL) was not observed in Monofer patients but occurred in 11.3% of Injectafer patients.

Data from the trials also suggested even a single dose of ferric carboxymaltose could adversely impact an individual’s entire skeleton, providing a possible explanation for other potential Injectafer side effects, including osteomalacia and bone fractures.

Injectafer Side Effects: What is Hypophosphatemia?

Severe hypophosphatemia occurs when the amount of phosphorous in the blood falls below 1mg/dL). Symptoms typically include:

• Muscle weakness
• Fatigue
• Bone pain
• Bone fractures
• Loss of appetite
• Irritability
• Numbness, tingling, or tremors
• Confusion

If hypophosphatemia goes untreated, victims may experience respiratory failure, muscle weakness, cardiac arrest, seizures, coma, and even death.