Other than LLY and MRK, BACE programs I know of include the ones from BI (#msg-38745008) and Astellas (#msg-28785891). I may be missing some others.
LGND has a BACE inhibitor partnered with MRK through their prior acquisition of Pharmacopeia ( http://www.ligand.com/pipeline ). I am assuming the MRK BACE inhibitor referenced is different from the LGND/Pharmacopeia BACE inhibitor.