The study was comprised of 2 parts : in part 1 , patients were randomized to either intravenous ( IV ) dinaciclib ( 50 mg/m2 ) or oral erlotinib ( 150 mg ) using an adaptive Bayesian design that adjusted the randomization ratio in favor of the more active arm , and in part 2 , patients who had progressed on erlotinib were permitted to cross over to receive dinaciclib at the same dosage as in part 1 .