Study of the Safety and Effects of ALN-CFB, an Experimental RNA Drug, in Adults with Paroxysmal Nocturnal Hemoglobinuria and Ongoing Anemia While on C5 Inhibitor Treatment

What this Trial Is About

Researchers are studying an experimental drug called ALN-CFB for adults with Paroxysmal Nocturnal Hemoglobinuria PNH who continue to have anemia despite treatment with a complement component C5 inhibitor. This study aims to evaluate the safety, tolerability, and initial effectiveness of ALN-CFB compared to a placebo. The study also examines how ALN-CFB affects levels of Complement Factor B protein in the blood and how the drug is processed in the body. Participants will receive either ALN-CFB or a placebo in a randomized, double-blind manner. The study includes a single-ascending dose escalation design to find the appropriate dosing. The protocol will be updated after initial data analysis to describe further parts of the study. Treatment duration and dosing schedules are defined by the study protocol. During the study, participants will undergo regular evaluations including blood tests to measure drug levels and Complement Factor B concentrations, and will be monitored for side effects for up to 365 days. Researchers will assess the occurrence and severity of treatment-emergent adverse events. The study spans several years, with the primary completion expected in late 2029 and final completion by mid-2031.

A First-in-Human Safety and Efficacy Study of ALN-CFB, a Small Interfering RNA (siRNA) Targeting Complement Factor B, in Adult Participants With Paroxysmal Nocturnal Hemoglobinuria With Persistent Anemia on a C5 Inhibitor