Aiolos Bio launches with $245M to race a phase-2-ready asthma antibody

Biotech developing antibody therapies for asthma and other respiratory conditions.

A phase-2-ready TSLP antibody in-licensed from China can be raced through asthma trials and expanded toward COPD fast enough to justify a $245 million day-one bet.

$245 million Series A raised at launch, one of the largest deals in a cohort of 22 asthma and respiratory startups that collectively raised close to $1.8 billion.

San Francisco- and London-based Aiolos Bio launched with AIO-001, having secured global rights to develop and commercialize the TSLP antibody outside China from Jiangsu Hengrui Pharmaceuticals.

The Series A funds phase 2 clinical trials of AIO-001 in moderate-to-severe asthma patients, with potential applications of the antibody in chronic obstructive pulmonary disorder and other conditions to follow. The launch joined a heavily funded cohort: Upstream Bio had raised over $400 million and posted positive interim data the same week; Areteia Therapeutics launched in mid-2022 with $350 million — against a market where asthma costs the US health system over $50 billion a year.

In-licensing a phase-2-ready molecule deletes the riskiest years of a biotech's life — discovery and preclinical — before day one.

China-originated assets out-licensed for global rights became a repeatable sourcing channel for Western biotech launches.

$245 million at launch funds phase 2 outright, so the company's first act is a trial, not a fundraise.

The timing leans on a proven cohort — Areteia's $350M launch and Upstream's $400M-plus — showing investors already pay for respiratory pipelines.

When discovery takes too long, buy the molecule: in-licensing a phase-ready asset turns a startup's first years from research risk into pure execution.

As of October 2023 Aiolos was preparing phase 2 trials of AIO-001 in moderate-to-severe asthma, with COPD and other indications in view, backed by Atlas Venture, Bain Capital Life Sciences, Forbion, Sofinnova and RA Capital.