Kailera Therapeutics has secured $600 million in Series B financing led by Bain Capital Private Equity to advance its pipeline of next-generation obesity treatments, with the lead candidate KAI-9531 poised to enter global Phase 3 trials by year-end. The clinical-stage biopharmaceutical company, which emerged from stealth just one year ago with $400 million in Series A funding, represents one of the industry's most closely watched private biotechs in the lucrative cardiometabolic space.
Lead Candidate Shows Superior Efficacy
KAI-9531, an injectable dual GLP-1/GIP receptor agonist, recently demonstrated compelling efficacy data in Phase 2 trials conducted with Chinese partner Jiangsu Hengrui Pharmaceuticals. The drug achieved a 22.8% mean weight loss in overweight or obese patients after 36 weeks of treatment, surpassing the 20.9% weight loss demonstrated by Eli Lilly's Zepbound (tirzepatide) across the same treatment duration.
Notably, KAI-9531 showed no plateau in its treatment window, suggesting the injectable could have a high efficacy ceiling and potentially best-in-category weight loss profile. This performance positions the drug as a strong competitor in the rapidly expanding obesity therapeutics market.
Comprehensive Phase 3 Program Planned
Following successful end-of-Phase 2 meetings with the U.S. Food and Drug Administration, Kailera plans to initiate its global Phase 3 program by the end of 2025. The comprehensive program will include three trials targeting different patient populations: adults living with obesity or overweight with comorbidities, with and without type 2 diabetes, and an additional trial in adults living with a BMI of 35 or higher.
"With this funding, we will accelerate the advancement of our pipeline, including our lead program KAI-9531 that has the potential to deliver substantial weight loss for people living with obesity," said Ron Renaud, President and Chief Executive Officer of Kailera. "We look forward to starting our global Phase 3 trials of KAI-9531 by the end of this year—marking a pivotal step in our mission to deliver therapies that empower people with obesity to transform their health and live fuller, healthier lives."
Diversified Pipeline and Strategic Partnerships
Beyond KAI-9531, the Series B financing will advance KAI-7535, an oral small molecule GLP-1 receptor agonist that demonstrated competitive weight loss in a Phase 2 clinical trial in China, to global clinical trials. The company's broader pipeline includes KAI-4729, an injectable GLP-1/GIP/glucagon receptor tri-agonist, and KAI-9531 formulated as a once-daily oral tablet, both in preclinical development.
Kailera maintains strategic rights to new formulations of licensed products and rights of first refusal over selected assets in Hengrui's metabolic disease portfolio, providing potential for pipeline expansion. KAI-9531 itself was originally discovered and developed by Hengrui, which licensed it to Kailera upon the biotech's launch in October 2024.
Strong Investor Confidence
The Series B round attracted a prestigious investor syndicate including new participants Adage Capital Management LP, Canada Pension Plan Investment Board, Invus, Janus Henderson Investors, Perseverance Capital, Qatar Investment Authority, Royalty Pharma, Surveyor Capital (a Citadel company), and accounts advised by T. Rowe Price Associates. Existing investors Atlas Venture, Bain Capital Life Sciences, RTW Investments, and Sirona Capital also participated.
"Kailera is uniquely positioned to make an impact beyond the current market leaders with a lead asset poised to set the bar for the next generation of obesity treatments," said Chris Gordon, Partner and Global Co-Head of Bain Capital Private Equity. "The company's broader portfolio – spanning diverse mechanisms of action and routes of administration – further supports its potential to be a leader in obesity care."
Andrew Kaplan, Partner at Bain Capital Private Equity, will join Kailera's Board of Directors in conjunction with the financing. The transaction is subject to customary closing conditions and will be fully funded at closing.
