Eli Lilly ($LLY) is buying big into the idea that the latest and greatest cancer therapies can work even better in combination, inking agreements to study its drugs alongside immunotherapies from Merck ($MRK) and Bristol-Myers Squibb ($BMY). Under one agreement, Lilly will pitch in on a serious of trials involving Merck's Keytruda, a PD-1-blocking antibody approved last year. The pair will study how well Merck's treatment works in tandem with Lilly's pemetrexed, approved as Alimta; ramucirumab, marketed as Cyramza; and necitumimab, an investigational drug that targets EGFR. Separately, Lilly has agreed to study its in-development galunisertib alongside Bristol-Myers' recently approved Opdivo, another immunotherapy, in a Phase I/II trial targeting glioblastoma, hepatocellular carcinoma and non-small cell lung cancer. Merck's release | Bristol-Myers' release