Figure 1. Top: Industry average attrition curve, showing that for every 10 drug candidates entering the pipeline, 1 emerges as an NDA. Bottom: Common attrition scenarios. Yellow, hypothetical attrition curve of a company that has trouble killing failing projects; purple, curve of a company that kills bad projects quickly; dark blue, industry average attrition curve. The dashed line shows an improved input-to-output ratio of 5:1 instead of 10:1, which is achieved if a company can increase the number of NDAs by 1 more in 10.