Dec 1 (Reuters) - Biotech firm Roivant Sciences (ROIV.O) on Thursday launched a company with Pfizer Inc (PFE.N) focused on an experimental bowel disease treatment, as the drugmakers seek to tap into a multibillion dollar market. The drug, RVT-3101, was originally developed by Pfizer, which will hold a 25% stake in the new business, with Roivant holding the majority interest. SVB Securities analyst David Risinger says the deal shows how Pfizer is prioritizing research spending for its oral ulcerative colitis drug, etrasimod, which holds a near-term blockbuster opportunity. RVT-3101 could represent a nearly $15 billion commercial opportunity in the United States for Roivant as a treatment for both ulcerative colitis and Crohn’s disease, said Risinger. Pfizer has also licensed its inflammatory autoimmune disease drug brepocitinib to Roivant in exchange for a 25% stake in another jointly held company called Priovant.

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