A company developing T cell-based therapies for autoimmune diseases has raised its latest round of venture capital financing. Cabaletta Bio said Thursday that it closed a $50 million Series B funding round. New investors include Deerfield Management, Boxer Capital of Tavistock Group, Redmile Group and Cormorant Capital. Existing investors include Adage Capital Management, 5AM Ventures and an undisclosed public equity healthcare investor. The company said it will use the money to fund manufacturing capabilities and translational research to complement its relationship with the Center for Cellular Immunotherapies at the University of Pennsylvania Abramson Center. Penn, an early seed investor in Cabaletta, sold some of its shares to investors, which enabled more to participate in the Series B financing. Radnor, Pennsylvania-based Cabaletta previously closed a $38 million Series A funding round in May. The company said at the time that it planned to file an Investigational New Drug application for its lead product candidate in the second half of this year. The company is developing what it calls chimeric autoantibody receptor T-cell, or CAAR-T therapies, which are similar to chimeric antigen receptor T-cell – CAR-T – therapies, except they’re designed to be used in autoimmune diseases instead of cancers. Cabaletta was spun out from research at Penn, which also developed what later became Novartis’s CAR-T therapy, Kymriah (tisagenlecleucel), which has Food and Drug Administration approval for treating acute lymphoblastic leukemia in pediatric patients and diffuse large B-cell lymphoma in adults. The CAAR-T is designed to selectively eradicate B cells that express a protein called DSG3 in patients with an autoimmune disease called mucosal pemphigus vulgaris. The use of adoptive T-cell therapy in autoimmune disorders remains unexplored relative to hematology-oncology. A search for CAR-T studies in autoimmune diseases on ClinicalTrials.gov turned up two entries. Both originated in China: one sponsored by Shanghai GeneChem in systemic lupus erythematosus that has not been updated in nearly a year, but mentions without elaborating further CAR-Ts being used in multiple sclerosis; and another study, not yet recruiting, in AQP4-IgG seropositive neuromyelitis optica spectrum disorders, sponsored by the Chinese People’s Liberation Army Hospital in Beijing. Cabaletta’s CAAR-Ts are structurally similar to certain CAR-Ts – particularly Kymriah and also Celgene’s JCAR017 (lisocabtagene maraleucel) – in the sense that they use a costimulatory domain called 4-1BB to enhance production of cytokines and a CD3-zeta signaling domain to mediate downstream signaling during T-cell activation. The other FDA-approved CAR-T, Gilead Sciences’ Yescarta (axicabtagene ciloleucel), uses a different costimulatory domain called CD28. Photo: aurielaki, Getty Images
Autoimmune disease therapy firm Cabaletta Bio has raised $$38mm in a series B funding round. The extra capital, which follows a 50 series A, will be put to use funding the manufacture of the Pennsylvania-based company's chimeric autoantibody receptor T cell (CAAR-T) therapies. This system borrows the techniques used in chimeric antigen receptor T-cell methods for cancer treatments, and instead applies them to autoimmune diseases. The CAAR-T selectively rids mucosal pemphigus vulgaris patients of DSG3 protein-expressing B cells by using the 4-1BB costimulatory domain to boost cytokine production and a CD3-zeta signalling domain to control signalling during T-cell activation.