 Acceleron Pharma NASDAQ:XLRN and Organovo NASDAQ:ONVO are both medical companies, but which is the better stock? We will compare the two companies based on the strength of their profitability, institutional ownership, risk, valuation, dividends, earnings and analyst recommendations. Institutional Insider Ownership 90.0 of Acceleron Pharma shares are owned by institutional investors. Comparatively, 48.6 of ... 