Placebo-controlled study in neuromyelitis optica-Ethical and design considerations

Background: To date, no treatment for neuromyelitis optica (NMO) has been granted regulatory approval, and no controlled clinical studies have been reported.

Objective: To design a placebo-controlled study in NMO that appropriately balances patient safety and clinical-scientific integrity.

Methods: We assessed the "standard of care" for NMO to establish the ethical framework for a placebo-controlled trial. We implemented measures that balance the need for scientific robustness while mitigating the risks associated with a placebo-controlled study. The medical or scientific community, patient organizations, and regulatory authorities were engaged early in discussions on this placebo-controlled study, and their input contributed to the final study design.

Results: The N-MOmentum study (NCT02200770) is a clinical trial that randomizes NMO patients to receive MEDI-551, a monoclonal antibody that depletes CD19+ B-cells, or placebo. The study design has received regulatory, ethical, clinical, and patient approval in over 100 clinical sites in more than 20 countries worldwide.

Conclusion: The approach we took in the design of the N-MOmentum trial might serve as a roadmap for other rare severe diseases when there is no proven therapy and no established clinical development path.