UCB’s growth driver squares up against the competition

UCB's bimekizumab has already beaten Humira and Stelara in psoriasis, and now needs to perform against Novartis’s Cosentyx. The head-to-head Be Radiant study will read out shortly.

The trial is an important validation, since Cosentyx, an anti-IL-17A MAb, is forecast to be the 2026 market leader, according to EvaluatePharma sellside consensus. However, Abbvie’s anti-IL-23 MAb Skyrizi is viewed as the most effective. Targeting IL-23 has significantly improved treatment outcomes in the skin disease, leaving bimekizumab's task of taking market share a tough one.

Be Radiant enrolled 743 patients with moderate to severe plaque psoriasis, and measures week-16 PASI100 scores as primary endpoint. In bimekizumab's phase IIb Be Able trial the best 12-week PASI100 responses were 56% on 320mg, and 60% on 160mg, with a 320mg loading dose.

Cosentyx itself has shown peak effects at week 16, with a 300mg dose yielding 37-42% PASI100 responses in its Erasure and Fixture phase III studies. Jefferies analysts expect bimekizumab to be numerically better than, but not superior to, Cosentyx – but it could still have a place in the market given its superiority over Humira and Stelara.

Detailed data from the Be Ready and Be Vivid studies, against placebo and Stelara respectively, will be released at the virtual AAD meeting that starts on Friday. The co-primary endpoints of these studies were PASI90 and IGA response, defined as clear or almost clear, at week 16.

Bimekizumab, an IL-17A and IL-17F inhibitor, is forecast by the sellside to become UCB’s biggest growth driver, with 2026 sales seen reaching $947m. A filing is expected soon.

However, psoriasis is an incredibly crowded space, with Cosentyx and Skyrizi vying for top spot. In a head-to -head trial run by Abbvie Skyrizi showed a 74% PASI 90 response at week 16, compared with 66% for Cosentyx. At one year the PASI 90 numbers were 87% for Skyrizi and 57% for Cosentyx.

Jefferies analysts note that bimekizumab could have greater potential in psoriatic arthritis and ankylosing spondylitis, where phase III data are due by the end of next year. Studies in hidradenitis suppurativa also recently started.