Dosing Patterns of Patients with Paroxysmal Nocturnal Hemoglobinuria Treated with Ravulizumab in the United States: A Retrospective Claims-Based Analysis

Paroxysmal nocturnal hemoglobinuria (PNH) is a rare blood disease. Complement factor 5 (C5) inhibitors can help treat PNH symptoms; health care providers administer C5 inhibitors to patients during clinic or office visits. Eculizumab was the first C5 inhibitor approved for PNH. Some patients still experience symptoms with approved eculizumab doses and may need to receive larger or more frequent doses than recommended. The new C5 inhibitor ravulizumab offers reduced dosing frequency and is dosed on the basis of patients’ body weights. This study assessed ravulizumab doses administered to patients with PNH in the USA using insurance claim records. Studied patients were 12 years or older and received two or more ravulizumab doses between June 21, 2019 and May 6, 2021. Researchers assessed ravulizumab doses administered to patients on the basis of body weight distribution of the US general population. The average first (loading) ravulizumab dose administered to 433 patients was 3316 mg. This was above the largest recommended loading dose of 3300 mg for patients weighing 100 kg (220 pounds) or more. Over nearly 12 months on average, the average maintenance dose administered was 3403 mg. Researchers estimated that larger loading doses than recommended were administered to almost 6 out of 10 patients and larger maintenance doses than recommended were administered to almost 3 out of 10 patients. This study found that larger than recommended ravulizumab doses may have been administered to some patients with PNH. More studies are needed to evaluate treatment response to complement inhibitors in patients with PNH.