Traditional medicine is often based on trial and error in patient care. We know from decades of experience that any given drug will work miracles in some patients and poorly or not at all in others. Variances in the disease also affect drug efficacy. For example, certain cancer tumors respond well to chemotherapy, while others build up a resistance over time. What we haven’t known is how to predict drug outcomes in advance of putting the patient through the regimen. But thanks to new developments, including and most especially big data analytics, that’s about to change.