Significant Crossover Investment and Background

Windward Bio, a Swiss-based clinical-stage biotech company headquartered in Basel, has successfully completed a $165 million crossover financing round, led by OrbiMed. This investment brings the company's total funding to over $365 million since its establishment in January 2025. The round saw participation from prominent global venture capital firms, including Novo Holdings, RA Capital, and Sanofi Ventures. This demonstrates strong investor confidence in the long-term potential of therapies for chronic respiratory diseases, even within the currently challenging global biotech investment landscape. The secured funds will be primarily used to accelerate clinical trials for key pipeline assets and expand the company's platform.

Clinical Strategy for Lead Pipeline Candidate 'WIN378'

Windward Bio's core asset, 'WIN378' (HBM9378/SKB378), is a fully human anti-TSLP (Thymic Stromal Lymphopoietin) monoclonal antibody acquired through a deal with Kelun-Biotech and Harbour BioMed, valued at up to $970 million. The company is currently conducting a global Phase 2/3 clinical trial, known as the POLARIS study, in patients with severe asthma. Phase 2 data is expected in the second half of 2026, with plans to initiate a Phase 3 trial in the fourth quarter. Additionally, the company recently initiated patient enrollment in the Phase 2 SIRIUS trial for chronic obstructive pulmonary disease (COPD), rapidly expanding its respiratory portfolio. WIN378 is being developed as a long-acting, twice-yearly administered therapy, aiming to significantly improve patient convenience and treatment adherence, positioning it as a potential game-changer.

Differentiation of Follow-up Pipeline Candidate 'WIN027'

In addition to its lead asset, the company is also advancing the clinical development of 'WIN027' (QX027N), acquired from Qyuns Therapeutics in a deal valued at up to $700 million. WIN027 is a long-acting bispecific antibody that simultaneously targets TSLP and interleukin-13 (IL-13). It is currently in Phase 1 clinical trials, with data expected in late 2026. The company plans to initiate a proof-of-concept (PoC) study in the fourth quarter of 2026, targeting a broad range of immune and skin diseases, including asthma and atopic dermatitis. By blocking multiple pathways, WIN027 aims to provide a new therapeutic option for severe patients who do not respond to existing single-target therapies.

Competitive Landscape in the TSLP Therapeutic Market

The global respiratory biologics market is currently led by 'Tezspire' (tezepelumab-ekko), co-developed by AstraZeneca and Amgen. Tezspire, the first anti-TSLP therapy, received FDA approval in December 2021 and generated $1.936 billion in revenue in 2025, representing a 50% year-over-year growth. However, Tezspire requires administration every four weeks, while Windward Bio's WIN378 aims for a twice-yearly administration schedule, offering a significant advantage in terms of convenience. In the global asthma biologics market, which is estimated at $7.4 billion to $9 billion in 2025, this convenience could be a key factor in enabling WIN378 to rapidly gain market share, despite being a later entrant.