Priced at $16, Kailera Raises $625M in Largest Biotech IPO Since 2018

Kailera Therapeutics priced its IPO at $16 a share Friday, raising $625 million, the largest biotech public offering in recent memory, topping Moderna’s $604 million listing from 2018.

The Waltham, Massachusetts company sold 39 million shares, over-shooting the 33.3 million it had guided last week. It priced at the top of its $14-$16 range, and underwriters hold a 30-day option to buy another 5.8 million shares at the same price — which would bring total proceeds to $717.8 million.

The closest obesity IPO comp is Metsera, which raised $289 million in January 2025 and was bought by Pfizer eleven months later for $10 billion after a bidding war with Novo Nordisk. Kailera isn’t a takeout target yet, but the Metsera comp will be on every investor’s mind from here.

What does the buyer actually get? The lead asset is injectable ribupatide, a GLP-1 licensed from Jiangsu Hengrui Pharmaceuticals, currently in three global phase 3 trials. In a Chinese late-stage study, it showed mean weight loss of nearly 18% at 48 weeks. Kailera has positioned it as a potential best-in-class option against Eli Lilly’s Zepbound, without a head-to-head trial to support the claim.

Kailera has budgeted $150 million for an oral ribupatide, which showed mean weight loss of up to 12.1% over 26 weeks in early data, with phase 3 planned for Q2 2028. Another $50 million goes to KAI-7535, a once-daily injectable small-molecule GLP-1 in phase 2. A fourth asset, KAI-4729, is in phase 1 in China.

The company’s original IPO plan projected $458.7 million in net proceeds. Kailera didn’t just meet guidance. It blew past it.

Diana Kowalski