BASEL, Switzerland — September 23, 2026
Roche announced positive prespecified interim results from the ongoing Phase 3 IMAgINATION study of investigational sefaxersen in adults with primary IgA nephropathy (IgAN). Sefaxersen achieved the study’s primary endpoint, demonstrating statistically significant and clinically meaningful reductions in proteinuria versus placebo at Week 37, measured using the 24-hour urine protein-to-creatinine ratio (UPCR). The once-monthly subcutaneous therapy is designed to inhibit complement factor B production in the liver, targeting a key component of the alternative complement pathway implicated in IgAN-related kidney damage. No new safety signals were identified.
Sefaxersen Reduces Proteinuria in Phase 3 IMAgINATION
The IMAgINATION study enrolled 459 patients with primary IgAN at high risk of disease progression, who were randomized 1:1 to receive sefaxersen or placebo for 105 weeks. The primary endpoint is the change from baseline in UPCR at Week 37, while the study will continue to assess longer-term kidney function through estimated glomerular filtration rate (eGFR) at Week 105. Proteinuria is an important marker of kidney damage, and reductions in UPCR are associated with preservation of long-term kidney function. Roche plans to present the interim findings at an upcoming medical congress and share the data with health authorities.
Sefaxersen Targets Complement Factor B in the Liver
Sefaxersen is an investigational liver-directed antisense oligonucleotide designed to inhibit production of complement factor B, which plays a role in the alternative complement pathway involved in IgAN. By reducing circulating factor B, the therapy is intended to decrease complement pathway activity and downstream kidney damage. Sefaxersen is designed for once-monthly subcutaneous administration and potential self-administration, providing a targeted approach to chronic treatment. Earlier Phase 1 and Phase 2 studies reported reductions in proteinuria and plasma complement factor B, with a generally favorable tolerability profile.
Advertisement
Roche Advances Sefaxersen Toward Potential IgAN Treatment
The positive interim results mark an important clinical development milestone for Roche’s immunology portfolio, while the IMAgINATION trial continues to its longer-term kidney function assessment. IgAN is a chronic autoimmune kidney disease that can progress to kidney failure, with up to 50% of patients potentially developing end-stage kidney disease within 20 years of diagnosis. Roche licensed sefaxersen from Ionis for the treatment of complement-mediated diseases. The company said the ongoing study and planned regulatory interactions are intended to support development of the therapy for patients at high risk of disease progression.
Source :Roche press release
