For over 50 years, all new medications have been tested in patients using a similar approach, consisting of three consecutive phases of clinical trials. Each phase of testing produces data that helps to establish the new medication’s effectiveness and safety.
Subsequently, these data are used by regulatory agencies—such as Health Canada and the Food and Drug Administration (FDA) in the US—to decide whether the new medication should be made available to all patients diagnosed with a particular disease.
In the past 15 years, the FDA and Health Canada have accelerated their approval process in an attempt to make new drugs to treat serious illnesses available faster. As a result, some anticancer drugs have been approved without being tested in phase III randomized controlled trials (RCT).
The repercussions of approving drugs without supporting RCTs have not been examined thoroughly.
“Many researchers are concerned by the rapid approval process. They are not convinced that a drug’s benefit and potential toxicities in routine clinical practice can be predicted accurately without RCTs,” said Dr. Eitan Amir, a Clinical Researcher at the Princess Margaret Cancer Centre.
To address this, Dr. Amir led a study evaluating the effect of RCTs on changes to drug labels. Because drug labels contain important safety information—such as dosage, side effects and other warnings—changes made to labels can act as an indicator of potential problems with the approval process. He examined 59 anticancer drugs that were approved by the FDA between 2006 and 2016 and found that common side effects listed on drug labels were more likely to change for drugs that had not been tested in RCTs.
“Our findings suggest that rapid approval of drugs without supporting RCTs help patients receive new drugs faster at the expense of complete safety data. Health care professionals should be aware of this and should practice increased vigilance when prescribing such drugs.” says Dr. Amir.
This work was supported by The Princess Margaret Cancer Foundation.
Shepshelovich D, Tibau A, Goldvaser H, Molto C, Ocana A, Seruga B, Amir E. Postmarketing Modifications of Drug Labels for Cancer Drugs Approved by the US Food and Drug Administration Between 2006 and 2016 With and Without Supporting Randomized Controlled Trials. J Clin Oncol. 2018 Apr 11. doi: 10.1200/JCO.2017.77.5593.