Principia Biopharma Inc., a South San Francisco-based developer of small molecule drugs within the fields of autoimmune disease and oncology, has raised $50 million in Series B funding. Sofinnova Ventures led the round, and was joined by return backers Morgenthaler Ventures, New Leaf Venture Partners, OrbiMed, SR One and Mission Bay Capital. The company previously raised $40 million.www.principiabio.com