Pfizer’s new FDA-approved ulcerative colitis drug Velsipity comes from its $6.7 billion Arena Pharmaceuticals acquisition. The small molecule will compete against blockbuster Bristol Myers Squibb drug Zeposia, which addresses the same target.

Merck is acquiring Prometheus Biosciences and a lead drug candidate in development for inflammatory bowel disorders. The deal comes as Merck looks for drug prospects that could make up for revenue declines facing blockbuster seller Keytruda, which faces patent expirations in coming years.

Single-cell analysis biotech Celsius Therapeutics has raised $83 million to advance its pipeline of drugs for autoimmune disorders and cancer. The startup’s lead autoimmune program, a TREM1-blocking antibody for inflammatory bowel disease, is expected to begin human testing in early 2023.

Sales of blockbuster Pfizer drug Xeljanz are under pressure from a stronger safety warning placed across that drug’s entire class. In acquiring Arena Pharmaceuticals for $6.7 billion, Pfizer gets a lead compound with a different and potentially safer approach to treating inflammatory conditions.

Prometheus Biosciences is taking a precision medicine approach to developing drugs and diagnostics for inflammatory bowel disease. The IPO cash will fund support its pipeline of IBD drug candidates for specific patient subpopulations.