Most approved oncology drugs do not offer better survival rate or quality of life, say researchers
A retrospective cohort study, published in the British Medical Journal, has found no conclusive evidence that most oncology treatments approved for use by the European Medicines Agency (EMA) offered survival or quality of life benefits to patients, giving rise to calls for an increase in the evidence bar.
The study, performed by researchers from the UK and Latvia, evaluated the availability of evidence on survival and quality of life benefits of drugs that had been approved by the EMA between 2009 and 2013.
In this timeframe, the EMA approved 48 cancer drugs for 68 indications and of these, eight indications were approved based on single-arm studies. At the time of market approval, the researchers found that an improvement in quality of life was demonstrated in only 7 of the 68 indications. Additionally, when approved, 44 of the indications did not offer a better survival rate, although when performing a post-market evaluation on these an increase in life expectancy was found in three indications and a better quality of life in five.
During the follow up of the approved therapies and their indications — median of 5.4 years — the researchers found that 35 indications demonstrated a significant improvement in survival or quality of life. Out of these, 23 were associated with a survival benefit that
could be scored with a survival benefit tool (ESMO-MCBS) and within these less than half (48%) were judged to have a ‘clinically meaningful’ benefit.
Speaking to The Guardian, co-author of the study Huseyin Naci, assistant professor of health policy at the London School of Economics, 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?
“What we find very surprising is that not very many studies are looking at overall survival or quality of life as their [primary] objective,” 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.”
Lead author of the study Dr Courtney Davis, a medical and political sociologist in the Department of Global Health and Social Medicine at King’s College London, explained: “We evaluated the evidence base for all new drugs entering the market over a 5 year period and found that the majority came onto the market without clear evidence that they improved patients’ survival or quality of life. A large number of people are undergoing treatment for cancer and little new information is available to guide patients and their treating clinicians regarding drug effectiveness. When expensive drugs that lack robust evidence of clinical benefit are approved and reimbursed within publicly funded healthcare systems, individual patients may be harmed and public funds wasted.”
As a result of their work, the researchers have asked for the evidence bar to be raised by the EMA before it grants market authorisation for new drugs.
