Rarity PBC, a Public Benefit Corporation dedicated to expanding access to transformative gene therapies for rare diseases, announced it has closed a $4.6 million seed financing round led by biotech investor Steve Oliveira, Head of Nemean Asset Management. The new funding will accelerate the development of Rarity’s lead program, a one-time autologous hematopoietic stem cell gene therapy for adenosine deaminase severe combined immunodeficiency (ADA-SCID).
The funding builds on Rarity’s exclusive licensing agreement with the UCLA Technology Development Group (TDG), which granted the company rights to the ADA-SCID gene therapy invented and developed by Dr. Donald B. Kohn at UCLA in collaboration with researchers at University College London. Clinical trials and long-term studies have demonstrated durable immune reconstitution in 59 of 62 children treated, and more than 70 children have now benefited from the therapy.
Proceeds from the round will be used to strengthen manufacturing capacity, prepare regulatory submissions for FDA approval, and establish the infrastructure needed for commercial readiness. Rarity’s leadership team, which includes Co-Founders Paul Ayoub, PhD, MBA (CEO), Roger Hollis, PhD (UCLA), and Katelyn Masiuk, MD, PhD (CSO), aims to ensure that every child affected by ADA-SCID can benefit from the therapy once approved.
Ayoub, who previously worked with Dr. Kohn at UCLA, emphasized that the company’s mission extends beyond development to sustainable patient access. Oliveira, who led the investment through Nemean Asset Management, said the firm was drawn to Rarity’s combination of a clinically validated therapy and its public benefit mandate.
The ADA-SCID gene therapy works by correcting the underlying genetic mutation that causes the disease. The treatment harvests a child’s own blood-forming stem cells, inserts a functional ADA gene using a viral vector, and reinfuses the corrected cells, allowing them to generate immune cells capable of fighting infections. Children born with ADA-SCID face life-threatening infections and rarely survive beyond early childhood without adequate treatment.
Rarity operates as a Public Benefit Corporation, balancing commercial execution with a legal commitment to public impact. The company focuses on developing sustainable models for the long-term availability of therapies for rare diseases.
The development of this program has also been supported by funding from the California Institute for Regenerative Medicine (CIRM), which provided grants (CLIN2-09339 and CLIN2-17078) to advance regenerative medicine research in California. CIRM’s collaboration with UCLA and Rarity is part of a broader effort to accelerate the translation of scientific discoveries into approved treatments.
KEY QUOTES:
“This investment is about turning proven science into sustainable patient reach.”
“With support from Nemean Asset Management, we’re moving faster to establish commercial-grade manufacturing, complete the work needed for FDA approval, and ensure that every child with ADA-SCID can benefit from this therapy, not just those in clinical studies.”
Paul Ayoub, PhD, MBA, Co-Founder and Chief Executive Officer, Rarity PBC
“We back mission-driven teams building therapies that truly change the standard of care. Rarity’s model, pairing a clinically validated, curative therapy with a public benefit mandate, has the potential to redefine how rare disease treatments reach patients.”
Steve Oliveira, Head of Nemean Asset Management
“This additional support builds directly upon the critical funding we’ve received from the California Institute for Regenerative Medicine (CIRM). The partnership between CIRM, UCLA, and Rarity exemplifies how collaborative models can accelerate the translation of science into approved treatments.”
Donald B. Kohn, MD, Co-Founder of Rarity PBC and Distinguished Professor, UCLA
