AnaptysBio’s Phase IIb trial of its rheumatoid arthritis (RA) treatment, rosinilimab, has seen some patients achieve the ‘highest ever’ responses at week 14, with 69% of patients achieving low disease activity.
The US-based company has announced results from its randomised RENOIR trial examining the safety and tolerability of rosnilimab (NCT06041269) in patients with moderate-to-severe RA who have until now been on conventional disease-modifying drugs.
Go deeper with GlobalData
The study achieved its primary endpoint in eliciting a mean change from baseline using the 28-Joint Disease Activity Score (DAS28-CRP) as a system of measurement, seeing statistical significance over placebo.
While the primary endpoint sought to establish safety and efficacy, secondary endpoints tracked disease progression via the mean baseline clinical disease activity index (CDAI) scale to achieve low disease activity (LDA).
Patients were split into four arms, receiving 100mg, 400mg and 600mg of rosnilimab or a placebo. Results saw not only statistical significance but also numerical significance across all dose ranges. By the end of week 14, the company stated that 69% of patients achieved LDA, the next best result besides full remission.
Anaptys president Daniel Faga said: “We are excited about these trial results and the impact they could have on patients living with RA. Rosnilimab is safe and well tolerated with the highest ever reported CDAI low disease activity at three months that, to date, is sustained and potentially deepening over six months.
“These findings are further supported by objective translational data and surpass our target product profile in the $20bn US RA market.”
Faga added that in Q2 2025, the company intends to report full six-month data and additional translational data it anticipates will further substantiate rosnilimab’s impact on restoring healthy immune homeostasis in RA and additional diseases such as ulcerative colitis (UC).
Research by GlobalData estimates that the RA market brought in $42.3bn in global sales in 2024, with the US market accounting for more than half of all sales at $25.3bn across the year. However, the US demand for RA treatments is expected to wane, with the figure estimated to drop to $22bn by the end of 2030. If approved, rosnilimab is expected to bring in an estimated $106m in the same period.
GlobalData is the parent company of Clinical Trials Arena.
Elsewhere in the market of RA treatment, X Biotech’s stock price has taken a hit after it announced a complete halt to its clinical programme in rheumatological diseases while it “seeks to understand the outcome” from a Phase II study. Meanwhile, IGM Biosciences has put a halt to the development of two of its autoimmune disease therapies, imvotamab and IGM-2644, after Phase I trials saw disappointing results.
