UCB's BIMZELX is carrying the company, and net cash has turned to net debt after two deals

The technology

UCB is a Brussels company that sells medicines for diseases of the immune system and the central nervous system. It generated revenue of €7.7 billion in 2025. Its growth now rests on five products: BIMZELX, RYSTIGGO, ZILBRYSQ, FINTEPLA and EVENITY, with CIMZIA and BRIVIACT as older earners.

UCB describes BIMZELX (bimekizumab) as the first and only approved medicine that selectively inhibits both IL-17A and IL-17F. Its first-half net sales were €1,528 million, up 91%. RYSTIGGO and ZILBRYSQ treat generalized myasthenia gravis through different mechanisms, FcRn and complement C5. EVENITY is a bone-building antibody sold with Amgen and Astellas.

The pipeline has been widened by purchases. Cizutamig, a BCMA by CD3 T-cell engager, came from Candid Therapeutics, and rezanecel, a cell therapy for epilepsy, from Neurona Therapeutics. UCB also develops dapirolizumab pegol for lupus with Biogen and the anti-tau antibody bepranemab.

The odds

BIMZELX is established, with four head-to-head superiority results in psoriatic disease, the latest BE BOLD against risankizumab in psoriatic arthritis. Newer programs carry the usual risk. Dapirolizumab pegol met its phase 3 primary endpoint, with a BICLA response of 50% against 35% on placebo, but the first ranked secondary endpoint was missed and a confirmatory trial is recruiting. Bepranemab missed the primary endpoint of its proof-of-concept study.

Industry data put the chance that a phase 3 program reaches a filing at 57.8%, and filing to approval at 90.6%. Programs starting in phase 1 reach approval about 7.9% of the time, which is the relevant figure for cizutamig and rezanecel. The nearest readout is the first phase 3 topline for STACCATO alprazolam, expected between the fourth quarter of 2026 and the first half of 2027.

The money

First-half revenue was €4,270 million, adjusted EBITDA €1,736 million and profit €1,111 million. On October 22 UCB raised guidance to revenue growth in the low twenties percent at constant rates and adjusted EBITDA growth in the low- to mid-forties.

The balance sheet moved the other way. Net financial debt was €2,821 million at June 30 against net cash of €7 million at year-end, after Neurona (up to $1.15 billion, $650 million upfront) and Candid (up to $2.2 billion, $2 billion upfront). Operating cash flow was €369 million against €711 million a year earlier. The 2025 dividend was a gross €1.45 per share.

The risks

Concentration is the first. BIMZELX was about 37% of first-half net sales by our division, and the October upgrade leaned on favorable net pricing dynamics as well as volume. Pricing depends on payer mix and U.S. policy. UCB's August 31 agreement with the U.S. government commits it to a more balanced pricing approach for future launches, with confidential terms.

Loss of exclusivity is the second. BRIVIACT lost U.S. exclusivity in February 2026 and fell 13% in the half, and CIMZIA lost U.S. patent protection in 2024 and sees Japanese protection expire in 2026. The company says there is no biosimilar competition today and none expected near term.

Execution is the third. The recent acquisitions add early-stage assets, and the first-half report notes that the prior-year comparison was helped by a channel mix true-up and the current half by a favorable accrual adjustment.

Our read

One fast-growing product is lifting the whole company, and management raised its outlook on July 30 and again on October 22. The balance sheet swung from net cash to net debt of about €2.8 billion in a half that included two acquisitions, and the pipeline now includes unproven modalities. The next tests are the February 25 results, the STACCATO alprazolam topline, and pediatric hidradenitis suppurativa data for BIMZELX in the first half of 2027.