# Windward Bio prices $175M IPO to advance two TSLP-targeting immune drugs, lead in Phase 2/3

- Published: 2026-11-13 13:27 UTC
- Section: Industry & People › Start-ups
- Tags: Windward Bio IPO, WIN378, TSLP inhibitor, Tezspire competitor, severe asthma, COPD, bispecific antibody, WIN027, biotech IPO 2026, Sanofi investment
- URL: https://realtech.media/news/rt-0605c0600c69e2f5f64fefb1_windward_bio_prices/

**Swiss biotech Windward Bio sold 10.3 million shares at $17, and Sanofi added $50 million. Its lead drug WIN378, in Phase 2/3 for asthma, is designed for dosing as rarely as twice a year.**

![Windward Bio prices $175M IPO to advance two TSLP-targeting immune drugs, lead in Phase 2/3](https://realtech.media/media/2026/11/239790f1813e9544.jpg)
*NIAID, Wikimedia Commons, CC BY 2.0*

Swiss immune drug developer Windward Bio raised $175 million in its initial public offering on Thursday, according to biopharmadive.com. [1] The company, formed two years ago, sold about 10.3 million shares at $17 apiece, in line with the projections it set earlier in the week. Trading starts Friday under the ticker "WWB". [1]

Sanofi, an earlier investor, bought another $50 million of shares in a concurrent private sale. Before the IPO, Windward had raised $365 million in venture funding. The offering is the 30th biotech IPO of the year. [1]

## WIN378 and the TSLP target

The lead program, WIN378, is an "ultra-long-acting" injectable drug that targets the inflammatory protein TSLP, as does Tezspire from AstraZeneca and Amgen, which generated nearly $2 billion combined last year. Tezspire is taken monthly. Windward said in a regulatory filing that WIN378 could be dosed as little as twice a year, and the company believes its design may yield improved potency. [1]

WIN378 is being studied in severe, uncontrolled asthma and in moderate-to-severe chronic obstructive pulmonary disease (COPD). Interim data from the mid-stage portion of a Phase 2/3 asthma trial showed the drug was well tolerated. Participants exhaled more air, a key measure of lung function, while a marker of airway inflammation and eosinophil counts decreased. [1]

The Phase 3 part of the asthma trial began in September, with results expected next year. A mid-stage COPD study started in June and should also produce data in 2027. [1]

## Second program and licensing

Windward is also developing WIN027, a bispecific antibody that targets TSLP and IL-13. The company expects Phase 1 results from healthy participants in the first half of 2027. It recently launched two Phase 2b studies of WIN027 in people with COPD, and a third trial in atopic dermatitis could begin next year. [1]

TSLP is a crowded field: Windward competes with AbbVie, Pfizer, Upstream Bio and Generate Biomedicines, and some of them are working on multifaceted antibodies similar to WIN027. [1]

Both programs were licensed from Chinese drugmakers. WIN378 came from Kelun Biotech, which co-developed it with Harbour BioMed, and WIN027 came from a deal with Qyuns Therapeutics. Windward paid $70 million up front in cash and equity and may owe another $1.6 billion contingent on R&D and sales milestones. [1]

This year is the busiest for drugmaker IPOs since 2021, with more than $8 billion raised, according to BioPharma Dive data. Windward is the ninth immune drug developer to price an IPO in 2026, a pace above every year since 2018. [1]

## Sources

1. [biopharmadive.com](https://www.biopharmadive.com/news/windward-ipo-pricing-immune-drugs-china-deals-tezspire/874533)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-0605c0600c69e2f5f64fefb1_windward_bio_prices/