- Preclinical data demonstrate robust in vivo engineering of CD8+ CAR T cells, profound B cell depletion in blood and tissues, and repopulation with predominantly naïve B cells in non-human primates
- Results obtained without the need for lymphodepletion chemotherapy
- Data supports Capstan’s plans to advance CPTX2309 into the clinic in mid-2025
SAN DIEGO--(BUSINESS WIRE)--Capstan Therapeutics, Inc. (“Capstan”), a biotechnology company dedicated to advancing in vivo reprogramming of cells through RNA delivery using targeted lipid nanoparticles (tLNP), today announced preclinical data on CPTX2309, Capstan’s lead in vivo CAR-T candidate, at the American College of Rheumatology (ACR) Convergence 2024 in Washington, D.C.
“The preclinical data presented at ACR highlight the potential of our in vivo CAR-T technology, which combines the unprecedented potency of a living drug with the convenience, scalability, and predictability of a biologic,” said Ramin Farzaneh-Far, M.D., Chief Medical Officer at Capstan. “These data provide strong support to advance CPTX2309 into clinical trials in mid-2025.”
CPTX2309, a product of Capstan’s proprietary CellSeeker™ platform, delivers an mRNA payload encoding an anti-CD19 CAR to preferentially reprogram CD8-expressing cytotoxic T cells. The therapeutic goal of this next-generation approach is to achieve a reset of the immune system through rapid and deep B cell depletion in both blood and lymphoid tissues, without the need for lymphodepletion chemotherapy and avoiding limitations and drawbacks of conventional ex vivo CAR-T therapy.
ACR Presentation Data Highlights
- Treatment with CPTX2309 resulted in robust and preferential engineering of functional CD8+ CAR T cells in vitro and in small and large animal models, with up to 80% of CD8+ T cells reprogrammed to express CAR in non-human primate (NHP) models. Minimal CAR engineering was observed in CD4+ T cells and B cells.
- Deep depletion of B cells was observed in NHP blood and tissues, with repopulation of predominantly naïve B cells suggestive of an immune reset, consistent with what has been observed in autoimmune patients receiving conventional ex vivo engineered CD19 CAR T therapy.
- CPTX2309 effectively engineers CD8+ T cells obtained from patients with myositis, systemic lupus erythematosus, rheumatoid arthritis, scleroderma, Sjogren’s syndrome, and multiple sclerosis comparably with healthy donor cells, and irrespective of prior therapies including broadly utilized immune suppressive agents. The resultant CD19-CAR-T cells demonstrated killing of B cells from these autoimmune patients.
A copy of the posters and presentation will be added to the “Publications and News” section of Capstan’s website at www.capstantx.com.
About Capstan Therapeutics, Inc. (www.capstantx.com)
Capstan is a biotechnology company with a mission to multiply the therapeutic possibilities for patients by developing targeted in vivo RNA technologies. Our proprietary CellSeeker™ tLNP platform technology is composed of novel LNPs conjugated with a recombinant protein binder, such as a monoclonal antibody. tLNPs are designed to deliver payloads, including mRNA or gene editing tools, capable of reprogramming specific cell types in vivo. Capstan’s CellSeeker™ technology has the potential to generate transformative therapies with possible applications across a broad range of disease areas, including autoimmune disorders, oncology, fibrosis, and monogenic blood disorders. For more information, please visit www.capstantx.com and follow us on LinkedIn and X (Twitter).
Contacts
Investors:
Miguel Arcinas
Senior Vice President of Corporate Development
Capstan Therapeutics, Inc.
ir@capstantx.com
Media:
Rhiannon Jeselonis
Ten Bridge Communications
rhiannon@tenbridgecommunications.com
