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Aiolos Bio Launches with $245 Million Series A Investment to Advance Development of Novel, Phase 2-Ready TSLP Antibody

October 25, 2023

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  • Developing a potentially best-in-class TSLP antibody (AIO-001) that is dosed every 6-months for patients with respiratory and inflammatory conditions
  • Khurem Farooq, Co-Founder and Chief Executive Officer, will lead an experienced team. Co-Founder Dr. Tony Adamis joins him on Board of Directors
  • John F. Milligan, industry veteran and former CEO of Gilead Sciences, named Chairman of the Board
  • Series A funded by Atlas Venture, Bain Capital Life Sciences, Forbion, Sofinnova Investments, and RA Capital Management

SAN FRANCISCO AND LONDON – October 24, 2023 – Aiolos Bio, Inc. (“Aiolos” or “the Company”) today announced its launch as a clinical-stage biopharmaceutical company focused on addressing the unmet treatment needs of patients with respiratory and inflammatory conditions. Aiolos launches with an oversubscribed $245 million Series A investment co-led by Atlas Venture, Bain Capital Life Sciences, Forbion, and Sofinnova Investments with additional investment from RA Capital Management (collectively the “Investor Group”).  The Company will advance its lead drug candidate, AIO-001, into a Phase 2 clinical trial in moderate-to-severe asthma patients and is actively evaluating additional development opportunities.

AIO-001 is an anti-thymic stromal lymphopoietin (TSLP) monoclonal antibody that has the potential to be administered only twice per year due to its differentiated potency and long half-life. TSLP inhibition has a proven role in addressing symptoms of severe asthma and is currently under investigation for additional immune conditions like Chronic Obstructive Pulmonary Disorder (COPD) and Chronic Spontaneous Urticaria (CSU). 

Aiolos Bio acquired exclusive rights for global development and commercialization of the drug from Jiangsu Hengrui Pharmaceuticals Co., Ltd (“Hengrui”) in August 2023. In multiple clinical studies, AIO-001 has demonstrated encouraging safety, tolerability, pharmacokinetics, and biological activity in healthy volunteers and asthma patients, with low immunogenicity.

Khurem Farooq, Co-founder and Chief Executive Officer, is a seasoned biopharmaceutical executive with more than 25 years of drug development and operational leadership experience.  Mr. Farooq has been appointed a member of the Board of Directors.  Prior to joining Aiolos, he was Chief Executive Officer of Gyroscope Therapeutics and previously served as Senior Vice President and Head of the Immunology and Ophthalmology business unit at Genentech, a member of the Roche Group.

“Aiolos has a unique opportunity to positively impact patients’ asthma outcomes.  I’m excited for the opportunity to lead this innovative Company and the wealth of experience our talented team brings to bear, from operating large-scale clinical trials in asthma, to overseeing more than 30 FDA approvals, to leading successful product launches in immune conditions like asthma, rheumatoid arthritis, and IPF,” said Mr. Farooq.  “We’re fortunate to have such an esteemed group of investors supporting our mission of helping patients and their caregivers breathe easier. We look forward to leveraging their experience and resources as we pursue the next phase of development for AIO-001.”

“AIO-001 has significant potential, demonstrating both high potency and long half-life in pre-clinical studies and initial clinical trials,” said Dr. Anthony (Tony) Adamis, Co-Founder and Board member.  “We believe it has the potential to help patients achieve better disease control with fewer injections, so their asthma doesn’t have to play such a central role in their lives. We are working to begin our Phase 2 trial as soon as possible.”

In conjunction with the Company’s launch, Aiolos announced that John F. Milligan, Ph.D., has joined the Board of Directors as Chairman.  Dr. Milligan was formerly the President and Chief Executive Officer at Gilead Sciences, where during a three-decade tenure with the company, he helped grow Gilead into a multi-billion-dollar business with global operations in over 40 countries and oversaw the successful development and commercialization of over 25 new therapies.

“I am excited to collaborate with a talented founding team that brings deep scientific and drug development expertise in respiratory therapies,” said Mr. Milligan.  “While the field of asthma treatment has made advancements in recent years, there remains a significant unmet need in treating patients suffering from severe asthma.  I look forward to an impactful partnership with Khurem and his team and supporting the advancement of Aiolos’ innovative lead therapy and the continued build-out of its operations.”


About AIO-001

AIO-001 is a monoclonal antibody that binds and blocks TSLP. TSLP has a validated, central role in driving inflammation, including in asthma. TSLP inhibition is the only biological approach that has demonstrated clinical benefit for moderate-to-severe asthma patients regardless of endotype. AIO-001’s unique properties allow for investigation in clinical trials as a therapy that only needs to be administered every six months.

AIO-001 was originally developed through early clinical stages by Jiangsu Hengrui Pharmaceuticals Co., Ltd, who retains commercialization rights to the greater China market. Hengrui has been developing and commercializing drugs for over 50 years and has one of the largest pharmaceutical market capitalizations in Asia.

About Aiolos Bio

Aiolos Bio is committed to helping patients breathe easier as we look to reimagine treatment for patients with respiratory and inflammatory diseases. Our lead drug candidate is AIO-001, a humanized, anti-TSLP mAb in development for moderate-to-severe asthma.  Our team has a long history of successful drug development in respiratory and immunological diseases – collectively amassing more than 30 FDA approvals – and seeks to leverage this expertise to meet the considerable unmet need that still exists for patients living with asthma around the world.  For more information, please visit