Catalio-Backed Rhapsogen Names Renato Skerlj, Ph.D., Chief Executive Officer

Dr. Skerlj brings significant drug development experience to lead biotech startup in its mission to develop next-gen autoimmune treatments

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Rhapsogen, an immunology company redefining the treatment paradigm for autoimmune diseases, today announced the appointment of Renato Skerlj, Ph.D., as the company’s new Chief Executive Officer, effective immediately.

Rhapsogen was launched by Catalio Capital Management’s venture strategy earlier this year. The company was co-founded by Prof. Jeffrey Ravetch, M.D., Ph.D., of Rockefeller University, and Prof. Eric Sundberg, Ph.D. of Emory University, both of whom are leaders in the immunology field and have made fundamental contributions to the understanding of how the immune system interacts directly with antibodies to protect against infection or cause autoimmune disease. In addition to his primary appointment, Dr. Jeffery Ravetch is a Catalio Venture Partner.

Dr. Skerlj is a seasoned biotechnology executive with more than 30 years of experience in drug discovery and development. He has authored over 70 scientific publications, is an inventor on more than 60 patents, and has played key leadership roles in advancing multiple therapeutics from discovery through clinical development and regulatory approval. Most recently, Dr. Skerlj served as President and Chief Executive Officer of Expansion Therapeutics, where he led the advancement of a proprietary RNA-targeting platform and overseeing company growth and financing. Previously, he was Co-Founder and Chief Scientific Officer of X4 Pharmaceuticals and a co-inventor of mavorixafor, which received FDA approval in 2024 for the treatment of WHIM syndrome. Across his career, Dr. Skerlj has built and led high-performing R&D organizations, contributed to successful financings and strategic transactions, and helped translate scientific innovation into impactful medicines.

“I am very excited by what we are building at Rhapsogen and look forward to working with our world-class team of immunology experts to deliver the solutions that autoimmune patients need and deserve,” said Dr. Skerlj.

“Dr. Skerlj’s leadership experience coupled with his deep drug development expertise make him well suited to maximize the potential of Rhapsogen’s first-in-class approach in autoimmune disease. We are thrilled to continue supporting the company’s growth under Dr. Skerlj’s leadership," said Matthew Hobson, Ph.D., Principal at Catalio Capital Management, who will be also joining Rhapsogen’s Board of Directors.

About Rhapsogen

Rhapsogen is a Cambridge, MA-based immunology company focused on redefining the autoimmune treatment paradigm by developing next generation therapies that rapidly neutralize pathogenic autoantibodies and prevent autoimmune inflammation and tissue damage while preserving the immune system’s ability to fight infection. The company was founded in 2025 by Dr. Jeffrey Ravetch (Rockefeller University) and Dr. Eric Sundberg (Emory University).

To learn more, please visit www.rhapsogen.com.

About Catalio Capital Management, LP:

Catalio Capital Management, LP, is a New York-based investment firm focused on the full lifecycle of innovative healthcare investing across private, public and credit markets. Catalio has exclusive partnerships with world-renowned serial scientist-entrepreneurs from around the globe who each have extensive academic and scientific achievements and who have also started multiple well-established companies based on their research. Catalio has offices in New York, London, and Washington, D.C. Learn more about Catalio Capital Management by visiting www.cataliocapital.com.