Capstan Therapeutics, a biotechnology startup developing medicines that reprogram cells inside the body, has raised another $175 million to bring its first prospect into clinical testing.The high-profile startup, formed by a group of pioneering cell therapy and messenger RNA researchers, secured the financing from a wide range of investors led by RA Capital and including five pharmaceutical companies, it said Wednesday. Johnson & Johnson is one of Capstans new backers, joining existing investors Pfizer, Bristol Myers Squibb, Eli Lilly and Bayer, among others. The startup has now raised $340 million since 2021. Capstan will use the funds to advance its work developing cell therapies designed to be administered through a single infusion, rather than via a laborious process that involves genetically manipulating cells in a lab. If successful, these in vivo cell therapies could help broaden the reach of so-called CAR-T therapy, and be more convenient and accessible to patients.The startup is one of a handful of young drugmakers to emerge in the last three years to pursue in vivo cell therapy research and attract funding. Multiple pharmaceutical companies have shown interest, investing in Capstan as well as others like Asgard Therapeutics and Ensoma. Another well-funded in vivo cell therapy startup, Umoja Biopharma, signed a collaboration deal with AbbVie in January.Capstans goal is to use messenger RNA technology to coax the body into making its own CAR-T cells. Early research published in Scienceand Natureshowed the feasibility of the approach in animals, but its nonetheless a daunting task thats never been attempted in humans.Our immune system is primed to attack anything thats delivering RNA. So the main challenge is, how do you make it stealth and get it into cells without causing a lot of immune activation? said CAR-T innovator and University of Pennsylvania scientist Carl June, one of Capstans co-founders, in an interview with BioPharma Dive in 2022.Since then, the company has progressed to the point that it now has a lead program. Called CPTX2309, it is being developed for autoimmune diseases and delivers an mRNA payload that redirects T cells to cells with the protein CD19.That particular protein is found on the antibody-making B cells that malfunction in a variety of autoimmune diseases. Its also the target of a number of cell therapies in clinical testing for lupus and other inflammatory conditions, all of which aim to induce a reset of a patients disease. Many of those programs involve ex vivo approaches, however.Capstan said the funds will get its lead program to early proof-of-concept studies and help advance the rest of its pipeline.We are grateful for the support of both new and existing investors as we enter a critical phase of execution, with the ultimate goal of bringing new therapeutic modalities to patients, said CEO Laura Shawver, in a statement. '