A new drug may be designated as a breakthrough therapy by the Food and Drug Administration (FDA) if it is intended to treat a serious or life-threatening disease and preliminary clinical evidence suggests it provides a substantial improvement over existing therapies.
If a drug is designated as breakthrough therapy, FDA will expedite the development and review of such drug. All requests for breakthrough therapy designation will be reviewed within 60 days of receipt, and FDA will either grant or deny the request.
Breakthrough Therapy designation is a United States Food and Drug Administration expedited drug development tool, which allows the FDA under Section 902 of the July 9, 2012 Food and Drug Administration Safety and Innovation Act, to grant priority review to drug candidates if preliminary clinical trials indicate that the therapy may offer substantial treatment advantages over existing options for patients with serious or life-threatening diseases.
A breakthrough therapy designation can be assigned to a drug if "it as a drug which is intended alone or in combination with one or more other drugs to treat a serious or life threatening disease or condition" and if the preliminary clinical evidence indicates that the drug may demonstrate substantial improvement over existing therapies on one or more clinically significant endpoints, such as substantial treatment effects observed early in clinical development."
Critics complain that most of these drugs are not actually “breakthroughs,” because they are based on preliminary evidence, including changes in surrogate markers such as laboratory measurements, that often don't reflect "meaningful clinical benefit." Even when they do, many of these benefits are not eventually confirmed in large clinical trials. And calling a drug a "breakthrough" drug gives the drug a marketing advantage which makes people believe that it is more effective than it actually is.
According to the FDA, in 2013 breakthrough therapy designations were assigned to Obinutuzumab(tradename Gazyva) by Hoffmann-La Roche for treatment of chronic lymphocytic leukemia,Ibrutinib and Sofosbuvir. In 2014 Ivacaftor, Ofatumumab, Ceritinib, Idelalisib, Ibrutinib (2nd approval), Eltrombopag, Pembrolizumab, Ledipasvir/Sofosbuvir, Nintedanib, Pirfenidone, Blinatumomab, Viekira Pak ombitasvir, paritaprevir, ritonavir and Nivolumab received the breakthrough therapy designation in 2014. In 2015 Ibrutinib (3rd approval) and Palbociclib received FDA breakthrough therapy designation.