Evidence base for drug approvals varies widely

Drawing on publicly available US Food and Drug Administration (FDA) documents, researchers looked at approvals for 188 new agents between 2005 and 2012.

Among their findings, 45% of drugs were approved following trials using surrogate end points as their primary outcome and comparative effectiveness information was available for less than half of indications.

The authors found the majority of trials evaluating drugs indicated for chronic treatment lasted less than one year “raising questions about the