Acceleron Pharma (Cambridge, MA) is a clinical-stage biopharmaceutical company focused on protein therapeutics for anemia, cancer, Duchenne Muscular Dystrophy and bone loss diseases, closed a $30.4M Series D financing. Participants have included Advanced Technology Ventures, Avalon Ventures, Bessemer Venture Partners, Celgene, Flagship Ventures, MPM Capital, Orbimed, Polaris Ventures, QVT Financial, Sutter Hill Ventures and Venrock.