J&J Halts Imaavy Combination Therapy for Rheumatoid Arthritis After Trial Setback

Johnson & Johnson's Imaavy (nipocalimab) has encountered a significant obstacle in its development program, as the company announced the discontinuation of its clinical development for rheumatoid arthritis (RA) in combination with anti-TNFα therapy. This decision follows disappointing results from the phase 2a Daisy proof-of-concept study, which showed no added benefit after 12 weeks of treatment in patients with refractory RA.

Imaavy's Mixed Fortunes

Imaavy, an FcRn-blocking monoclonal antibody, received FDA approval just four months ago for the treatment of generalized myasthenia gravis (gMG). This approval had positioned the drug as a potential blockbuster, with J&J projecting peak sales of over $5 billion. Despite the setback in RA, the company maintains confidence in Imaavy's potential across other immunology indications.

The drug's mechanism of action involves blocking the FcRn protein, which is responsible for circulating immunoglobulin G (IgG) antibodies implicated in various autoimmune diseases. Clinical data has demonstrated Imaavy's ability to significantly reduce IgG levels, including autoantibodies, while preserving other immune functions.

Ongoing Development and Competition

J&J continues to investigate Imaavy in several other immunology disorders, including Sjogren's disease (SjD). The company presented promising phase 2 data last year, marking the first demonstration of an FcRn blocker's effectiveness in SjD. This success contributed to Imaavy securing its fourth FDA fast-track designation, adding to those already obtained for gMG and two maternal-fetal diseases.

In the gMG market, Imaavy faces competition from established FcRn inhibitors. Argenx's Vyvgart, approved in 2021, and UCB's Rystiggo, which received FDA approval in 2023, are already on the market. However, J&J believes Imaavy could become the top-selling treatment in this indication due to its broader label.

Strategic Implications

The decision to halt Imaavy's development for RA in combination with anti-TNFα therapy represents a strategic pivot for J&J. The company acquired Imaavy through its $6.5 billion purchase of Momenta Pharmaceuticals in 2020, highlighting the significant investment and expectations placed on the drug.

While this setback may impact near-term prospects in the RA space, J&J's continued confidence in Imaavy's potential across other indications suggests a recalibration of its development strategy rather than a wholesale reevaluation of the drug's promise.