It’s hard to find anyone who hasn’t been touched by cancer. People who haven’t had cancer themselves will likely have a close friend or family member who has been diagnosed with the disease.
If the cancer has already spread, the diagnosis may feel like a death sentence. News that a new drug is available can be a big relief.
But imagine a cancer patient asks their doctor: “Can this drug help me stay alive longer?” And in all honesty, the doctor answers: “I don’t know. There’s one study that says the drug works, but it didn’t show whether patients lived longer, or even if they felt any better.”
A Look at the Research
A study published Sept. 18 in the British Medical Journal reviewed 39 clinical trials supporting the approval of all new cancer drugs in Europe from 2014 to 2016.The researchers found more than half of these trials had serious flaws likely to exaggerate treatment benefits. Only one-quarter measured survival as a key outcome, and fewer than half reported on patients’ quality of life.
Of 32 new cancer drugs examined in the study, only nine had at least one study without seriously flawed methods.
The researchers evaluated methods in two ways. First, they used a standard “risk of bias” scale that measures shortcomings shown to lead to biased results, such as if doctors knew which drug patients were taking, or if too many people dropped out of the trial early.
From Clinical Trials to Treatment—Faster Isn’t Always Better
Before a medicine is approved for marketing, the manufacturer must carry out studies to show it’s effective. Regulators such as the EMA, the US Food and Drug Administration (FDA), or Australia’s Therapeutic Goods Administration (TGA) then judge whether to allow it to be marketed to doctors.National regulators mainly examine the same clinical trials, so the findings from this research are relevant internationally, including in Australia.
How Is Effectiveness Measured Currently?
Approval of new cancer drugs is often based on short-term health outcomes, referred to as “surrogate outcomes,” such as shrinking or slower growth of tumors. The hope is these surrogate outcomes predict longer-term benefits. For many cancers, however, they have been found to do a poor job of predicting improved survival.Approving Drugs Without Enough Evidence Can Cause Harm
In an editorial accompanying this study, we argue that exaggeration and uncertainty about treatment benefits cause direct harm to patients if they risk severe or life-threatening harm without likely benefit, or if they forgo more effective and safer treatments.Inaccurate information can also encourage false hope and create a distraction from needed palliative care.
And importantly, the ideal of shared informed decision-making based on patients’ values and preferences falls apart if neither the doctor nor the patient has accurate evidence to inform decisions.
New cancer drugs are often very expensive. On average in the United States, a course of treatment with a new cancer drug costs more than $100,000.
Cancer patients need treatments that help them to live longer, or at the very least to have a better quality of life during the time that they have left. In this light, we need stronger evidence standards, to be sure there are real health benefits when new cancer drugs are approved for use.