In a bid to build out its pipeline beyond Soliris® (eculizumab), Alexion Pharmaceuticals has agreed to acquire Achillion Pharmaceuticals for US$930 M. The deal gives Alexon access to two clinical-stage complement Factor D inhibitors in development, including danicopan which is in Phase II and ACH-5228 which is in Phase I clinical trials. With the Achillion acquisition announced just days after UCB’s US$2.1 B acquisition of complement disease company Ra Pharmaceuticals, the deal is likely to invite scrutiny by the US FTC.