The suspension of a Phase IIb trial of Bristol-Myers Squibb's BMS-986094 nucleotide polymerase inhibitor resulted in a $1.8 billion write-off. Other expensive failures include a joint Pfizer-Johnson & Johnson candidate for Alzheimer's disease, an AstraZeneca and Targacept adjunct to antidepressant treatment, and an Eli Lilly & Co. schizophrenia drug.