The standards used by the U.S. Food and Drug Administration to approve new cancer drugs have been called into question for the lack of evidence supporting the fact that they can lengthen life or maintain quality of life, according to a study cited in the Milwaukee Journal Sentinel.
The paper, published in the Mayo Clinic Proceedings, concludes that the FDA approves cancer drugs that are not scientifically proven to extend life or maintain quality of life for cancer patients, according to the report. Instead, the FDA uses standards that rely on surrogate measures of effectiveness.
In cancer, surrogates are measures that show whether a tumor is growing or not, such as a CT scan. They do not assess quality of life or chances of survival.
When the FDA approves new cancer drugs, it can use accelerated approval or traditional approval. Accelerated approvals are based on a surrogate measure that is "reasonably likely to predict" the drug will increase overall survival, and traditional approvals are granted when a drug can produce "a favorable effect on an established surrogate for a longer or better life." However, the Mayo Clinic study argues many surrogates, such as CT scans, often do neither of these, according to the report.
Of the 25 drugs approved under the accelerated approval program between 2009 and 2014, 56 percent did not have supporting evidence that they extended life or maintained quality of life. Among the 30 drugs approved under traditional approval, 37 percent lacked similar evidence.
"I think that is indefensible," senior author Vinay Prasad, MD, an oncologist and assistant professor of medicine at Portland-based Oregon Health and ScienceUniversity, told the Milwaukee Journal Sentinel. "The FDA sets its own rules for when to use a surrogate. In a large percent of these approvals, the surrogate has never been studied. They just take it for granted."