UCB's Bimzelx (bimekizumab-bkzx) is proving to be a key player in psoriasis and hidradenitis suppurativa (HS), with new longer-term data presented at the American Academy of Dermatology (AAD) conference Friday likely to give its commercial momentum a bit more spark.The dual IL-17A/F inhibitor's success has been driving major sales growth for the Belgian drugmaker, skyrocketing from $154 million in 2023 to $632 million last year, blowing past consensus (see – Spotlight On: UCB's Bimzelx delivers strong growth on back of US approvals). In a recent note, Morningstar analysts said Bimzelx was on track to hit blockbuster status and generate over €1 billion ($1.1 billion) in sales in 2025.'New standard' for successIn a new analysis from the second extension of the Phase III BE BRIGHT study, UCB said 67.7% of patients with moderate-to-severe plaque psoriasis maintained complete skin clearance (PASI 100) at the five-year mark. The analysis, which looked at 153 patients who completed the extension period, also showed that 84.9% achieved near-complete clearance (PASI 90) over that five-year span.Additionally, roughly 70% of patients at risk for developing psoriatic arthritis saw their skin completely clear up with Bimzelx treatment at three years, close to the 72% rate seen in the overall treated group. The drug's long-term safety profile also remained consistent with previous findings, with nasopharyngitis, oral candidiasis, and upper respiratory tract infections being the most common adverse events.Fiona du Monceau, head of patient evidence at UCB, said the company is aiming to set "a new standard for treatment success."Bimzelx was first approved in the US in 2023 for plaque psoriasis, and racked up three more indications — psoriatic arthritis, non-radiographic axial spondyloarthritis and ankylosing spondylitis — last September.It scored its fifth and most recent approval two months later, when the FDA greenlit the drug for HS based on results from the Phase III BE HEARD I and II studies. Two-year data from the extension trial presented at AAD showed sustained disease control with Bimzelx, as well as the potential to help prevent long-term structural damage caused by draining tunnels (DTs), which are painful "passageways" that can form under the skin that drain pus and blood.UCB said 55.7% of patients with baseline DTs were tunnel-free at two years of treatment. Even in patients with five or more DTs at baseline, 41.1% had none after two years of therapy. Treatment also provided meaningful relief from disease-associated skin pain, with 63.6% of patients reporting no or mild skin pain at two years compared to just 10% at baseline.According to Jefferies analysts, Bimzelx revenues could accelerate further in 2025 given the drug's differentiated profile versus competitors in psoriatic arthritis and HS. Following its approval in HS late last year, a FirstWord poll of 29 dermatologists found that over a third expected Bimzelx to become a frequently used treatment option that is used preferentially over other therapies (see – Physician Views Results: Many dermatologists keen to embrace Bimzelx for HS).Rival readoutsHowever, competition in the HS space is intensifying. In a recent note, Morgan Stanley analysts said "competitive developments could become increasingly in focus" with several late-stage candidates expected to report data. These include MoonLake's Immunotherapeutics' IL-17A/IL-17F nanobody sonelokimab, Incyte's oral JAK inhibitor povorcitinib, and AbbVie's IL-1A/ IL-1B antibody lutikizumab.Phase III data for sonelokimab and povorcitinib are due this half, while a readout for lutikizumab is expected in 2026. Meanwhile, Eli Lilly plans to reveal further Phase IIb results for a subcutaneous formulation of its CXCR1/2 monoclonal antibody eltrekibart this year. For more, see – Spotlight On: How emerging agents could reshape the HS treatment landscape.