EXTON, PA, June 02, 2025 (GLOBE NEWSWIRE) -- Just over six months into its dual launch across Psoriatic Arthritis (PsA) and Axial Spondyloarthritis (axSpA), UCB’s Bimzelx (bimekizumab) is demonstrating meaningful promise, though prescriber momentum remains tempered by access hurdles and payer-imposed constraints, according to new findings from Spherix Global Insights' Launch Dynamix™ services.
Physicians across both PsA (n=76) and axSpA (n=73) have expressed strong clinical enthusiasm for Bimzelx, particularly citing its unique dual inhibition of IL-17A and IL-17F as a differentiator from existing IL-17 agents. In PsA, rheumatologists report confidence in the drug’s performance across both skin and joint domains and consider it a therapeutic advance over competitors like Novartis’ Cosentyx and Eli Lilly’s Taltz. In axSpA, particularly among more severe or refractory patients, Bimzelx is increasingly viewed as a preferred IL-17, with some physicians already positioning it ahead of established options in terms of anticipated efficacy and breadth of benefit.
Despite its favorable clinical profile, Bimzelx’s adoption is constrained by a consistently challenging reimbursement environment. In PsA, nearly all prescriptions require prior authorization, with step therapy requirements and payer preferences for legacy agents continuing to block earlier use. These access challenges are echoed in AS and nr-axSpA, where physicians cite not only high out-of-pocket costs and Medicare limitations but also a general lack of formulary inclusion across plans. While some rheumatologists note success in early line use, many describe regular denials and delays that often force them to default to more accessible agents despite clinical preference for Bimzelx. As one rheumatologist summarizes, “I like Bimzelx. The big headwind I'm facing now, it just gets denied by insurers. So commercial insurance coverage, which seems to always plague UCB products, is horrible. I'm hoping that will improve.”
To address these access barriers, some physicians are turning to samples and bridge programs. However, in PsA, just 13% of patients initiated on Bimzelx started with a sample or free drug, with a pattern similarly observed in axSpA. While sampling and bridge programs are providing a critical means to initiate Bimzelx, physician sentiments support that these are often used to navigate around access hurdles, with uncertainty remaining around consistent conversion to insurance coverage and sustainability of this approach.
While access barriers are a common thread, and also are common across many recently launched biologics in immunology, notable differences are emerging in how Bimzelx is being adopted and perceived across PsA versus axSpA. In PsA, two-thirds of rheumatologists have already prescribed Bimzelx, typically for patients with severe or flaring disease after failing multiple advanced therapies. Many express interest in moving the therapy earlier in the treatment algorithm but, again, remain limited by payer mandates. By contrast, adoption in axSpA is still ramping up, particularly in nr-axSpA, where just a minority of rheumatologists have used the product to date. Though uptake is slower, satisfaction levels remain high among those with prescribing experience, and many physicians expect to expand use as coverage improves.
In addition to ramped trial and utilization, promotional efforts from UCB are beginning to resonate. The majority of rheumatologists report contact with Bimzelx sales representatives, who are largely praised for their professionalism and ability to communicate key efficacy and safety differentiators. However, a notable subset of physicians in both PsA and axSpA have yet to be detailed, and limited awareness of support services—such as the Bimzelx Navigate program—suggests more work is needed to fully activate the prescriber base. Those who have engaged with Navigate report a positive experience, citing timely support and ease of use, though these accounts remain limited.
As the launches progress, the key question is whether UCB can convert strong clinical perceptions into real-world usage at earlier points in care. While Bimzelx is well-positioned from an efficacy standpoint, its long-term success will hinge on overcoming payer resistance and improving patient access.
Spherix Global Insights will continue to track Bimzelx’s PsA, AS and nr-AxSpA U.S. launch trajectory through its Launch Dynamix™ service through the first eighteen months of commercial availability.
Launch Dynamix™ is an independent service providing monthly benchmarking of newly launched products for the first eighteen months of commercial availability, augmented by a quarterly deep dive into promotional activity, barriers to uptake, and patient types gravitating to the launch brand.
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NOTICE: All company, brand or product names in this press release are trademarks of their respective holders. The findings and opinions expressed within are based on Spherix Global Insight’s analysis and do not imply a relationship with or endorsement of the companies or brands mentioned in this press release.
Lynn Price, Rheumatology Franchise Head Spherix Global Insights 4848794284 lynn.price@spherixglobalinsights.com
