Of 48 cancer drugs approved between 2009-2013, 57% of uses showed no benefits and some benefits were ‘clinically meaningless’, says BMJ study
Most cancer drugs that have recently arrived on the market have come with little evidence that they boost the survival or wellbeing of patients, research reveals.
Forty-eight cancer drugs were approved by the European Medicines Agency between 2009 and 2013 for use as treatments in 68 different situations.
But the study, which looked at the clinical trials associated with the drugs, reveals that at the time the therapies became available there was no conclusive evidence that they improved survival in almost two-thirds of the situations for which they were approved.
In only 10% of the uses did the drugs improve quality of life. Overall 57% of uses showed no benefits for either survival or quality of life.
Huseyin Naci, assistant professor of health policy at the London School of Economics, and a co-author of the study, published in the British Medical Journal, said: “We wanted to see once [the drugs] were already on the market did they actually generate some evidence to show that they improved or extended life?”
The team found that after a follow-up period of between three to eight years, 49% of approved uses were linked to no clear sign of improvement in survival or quality of life. Where survival benefits were shown, the team said these were clinically meaningless in almost half of the cases.
“What we find very surprising is that not very many studies are looking at overall survival or quality of life as their [primary] objective,” said Naci. He said that instead most of the studies examined indirect measures, such as x-rays or laboratory tests that were assumed to offer clues as to a drug’s survival benefits.
He added: “Unfortunately the expectation is that once the drugs are on the market then companies will be investing in [longer term] trials to then demonstrate overall survival benefits. But unfortunately these trials are not necessarily taken up and conducted.”
Naci said the findings did not mean patients should worry. “I think it is very important that no one is alarmed,” he said.
Carl Heneghan, professor of evidence-based medicine at University of Oxford, described the lack of drug improvement with regard to survival as disappointing, and called for a more rigorous approach to evaluating cancer drugs. “It is hard to understand why half the drugs were approved in the first place if they provide no clinically meaningful benefit,” he said.
But Winette van der Graaf, professor of personalised oncology at the Institute of Cancer Research, said that making decisions based on smaller studies looking at benefits other than overall survival, were important in making sure new treatments were swiftly made available to patients.
“In my area of research [on] rare cancers the level of evidence called for here is very hard to obtain, meaning that these patients would find it extremely difficult to gain access to new treatments,” she said, adding that large trials looking directly at survival could be expensive and lengthy.
“Ideally, studies should try also measuring early markers of treatment failure, so that health authorities can make well-balanced decisions.”
Emma Greenwood, Cancer Research UK’s director of policy, warned that the study did not necessarily reflect the situation in the UK where Nice (the National Institute for Health and Care Excellence) played an important role in deciding which drugs were available to patients.
“The study does highlight the importance of using real-world evidence from patients, on top of data from clinical trials, to build our understanding of how drugs work in a real-life setting. We’re already starting to see this happen through the cancer drugs fund in England, where patients can access promising new drugs while more data is collected on their effectiveness.”