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Cancer drugs that neither improve nor extend lives

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randomised clinical trials

More than 50% of cancer drugs available in the UK do nothing to extend or improve the lives of patients
The efficacy of drugs was not considered by authorities as a factor in the UK’s higher cancer mortality rates compared with other European nations
Recent scientific and technological advances have significantly changed our understanding of cancer biology and impacted cancer diagnoses and treatments
Increasingly traditional randomized controlled trials (RCT) are viewed as too long, too expensive and too inefficient

Cancer drugs that neither improve nor extend lives

A retrospective cohort study of drug approvals published in the October 2017 edition of the British Medical Journal, (BMJ) found that 57% of cancer drugs approved by the European Medicines Agency (EMA) between 2009 and 2013 and prescribed to UK patients do nothing to extend or improve their lives.

Recurring explanations for Britain’s cancer mortality rates lagging those of other European nations make no mention of the quality of cancer medicines. Although cancer drugs approved by the EMA might be expected to affect all European nations equally, drug efficacy is a significant factor in cancer care, and merits consideration. Not least because the ‘revolution’ in molecular science is responsible for the shift from the medicine for crowds to the medicine of molecules; from treating diseases to treating individuals. Traditional regulatory protocols support crowd-science medicine and struggle to find ways to adjust to molecular science.

In this Commentary

Before describing the findings of the BMJ study, we briefly provide descriptions of 4 of the 48 drugs scrutinized in the BMJ paper and approved by the EMA. Within this context we describe the role of the UK’s Cancer Drugs Fund (CDF) and its relation to the EMA. We then describe the findings of the BMJ study and mention a cautionary note about the research suggested by BMJ editors. It is not altogether clear that criticism of cancer drugs coming to market without showing any sign that they extend life will put pressure on regulatory bodies to change their protocols before recommending drugs for use in clinics. There is evidence to suggest an opposite position: that randomized controlled trials, the “gold standard” for drug delivery over the past 70 years, are increasingly challenged by molecular science and are changing as a result.

4 cancer drugs scrutinized

Four of the 48 drugs scrutinized by the study reported in the October 2017 edition of the BMJ were: 1. Everolimus, which is a type of targeted therapy for breast cancer, (also indicated for kidney cancer and brain tumours). It is taken as a tablet once a day for an average of 5.5 months at a cost of about £18,000 per patient per course. Each year, some 1,500 breast cancer patients are eligible for the drug. Evertlomus is manufactured by Novartis, and sold under the trade name Afinitor. The drug stops some of the growth of cancer cells and slows their spread. Side effects include diarrhoea, constipation, mild nausea or vomiting and weight loss. Evertlomus was approved by the EMA in 2012 without either survival rate or quality of life data. In 2016 it was moved on to routine provision through the National Institute for Health and Care Excellence (NICE), the UK government’s watchdog. 2. Bosutinib, which is a drug taken either as a tablet or a capsule and used by adult patients to treat chronic myeloid leukaemia (CML), which has an abnormal chromosome called the ‘Philadelphia chromosome’. 95% of people with CML have the Philadelphia chromosome. Bosutinib is manufactured by Pfizer, marketed under the trade name Bosulif and is used when other CML treatments no longer work or cause severe side effects. In 2013 bosutinib was approved by the EMA with no evidence that it extended life. Each year about 80 NHS England patients receive the drug at an annual cost per patient of about £45,000. Patients have blood tests before starting and during treatment to monitor the effect of the drug. Up to 85% of patients see white blood cells return to normal levels. The most common adverse reactions, which affect more than 20% of patients, include diarrhoea, nausea, abdominal pain, rash, anaemia, and fatigue. Serious adverse reactions reported include anaphylactic shock. 3.Panitumumab, which is a targeted biological therapy belonging to a group of drugs called monoclonal antibodies. These are drugs that stimulate the body's immune system to act against cancer cells. Panitumumab is used for the treatment of advanced bowel cancer, which has progressed after treatment with other drugs. It is administered via a small cannula into a vein and works by attaching itself to growth factor specific proteins found on the surface of cells and stopping them from attaching themselves to the cancer and triggering the cancer to divide and grow. Panitumumab is manufactured by Amgen and sold under the trade name Vectibix. The drug was approved by the EMA in 2011 without evidence that it extended life. However, more recent data suggest panitumumab boosts survival by 10 months more than other treatments. Common side effects include skin reactions, diarrhoea, nausea, tiredness and constipation. Each year about 84 NHS England patients are given the drug. In 2017 NICE made panitumumab routinely available at a cost of about £54,000 per year per patient. 4. Bevacizumab, which is a drug that blocks a cancer cell protein that helps cancers to grow by providing them with blood. It belongs to a class of cancer treatments, which interfere with the development of blood supply to cancers called ‘anti-angiogenesis therapies’. Bevacizumab is manufactured by Roche, marketed as Avastin and costs £42,000 per patient per year. It is administered intravenously, and side effects include mild headache, back pain, diarrhoea, loss of appetite, cold symptoms and dry or watery eyes. Bevacizumab was approved by the EMA in 2009 with no evidence that it extended life and is not available on the NHS. Initially the drug was available in the UK on the Cancer Drugs Fund but was stopped in 2015. Clinical studies show that bevacizumab stops the progression of the disease for an average of 3 months.

The UK’s Cancer Drugs Fund

These and the other drugs examined in the BMJ paper were all approved by the European Medicines Agency. This approval permits pharmaceutical companies to market their medicines across Europe. NHS England, however, will not use medicines unless NICE assesses them as showing value for money. The UK’s Cancer Drugs Fund (CDF) was specifically introduced in England in 2011 to provide a means by which NHS England patients could obtain cancer drugs rejected by NICE because they were too expensive. Some of the drugs deemed by the researchers to have shown no benefit are now available to UK patients, but only after pharmaceutical companies reduced their prices.

Findings

The BMJ study is significant because it is one of the only recent studies that has systematically examined evidence associated with the extent of the benefits of cancer drugs approved by the European Medicines Agency. Researchers, from Kings College London and the London School of Economics, who conducted the study assessed 48 cancer drugs for 68 indications approved during the 5 year study period and concluded that, at the time of market approval, there was an improvement in the quality of life for only 7 of 68 indications and no evidence of a survival gain for 44 indications. However, subsequent evidence showed that life was extended in 3 indications and quality of life was enhanced in 5.

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When drugs did show survival gains over existing treatments the benefits were marginal, the report says. Treatments that improved life expectancy gave patients a median of an extra 2.7 months of life often at significant cost. Notwithstanding, researchers stressed that when someone is dying of cancer even a few extra months of life with loved ones are priceless, and they also understood that it takes time to prove a drug will improve life expectancy. Notwithstanding, researchers suggested that drug firms could be needlessly raising the hopes of cancer patients and exposing them to unnecessary side effects. “At a minimum of 3.3 years after market entry, there was still no conclusive evidence that these drugs either extended or improved life for most cancer indications,” researchers said. Of the 68 cancer indications with EMA approval, and with a median of 5.4 years’ follow-up, 35 had shown a significant improvement in survival or quality of life, while 33 remained uncertain.

“It is remarkable that cancer drugs enter the European market without any clear data on outcomes that matter to patients and their doctors: longer survival and better quality of life,” said Huseyin Naci, a co-author. “There is a clear need to raise the bar for approving new cancer drugs. 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,” say the researchers. “There is growing concern that the benefits offered by many new treatments for cancer, which are often discussed and promoted as ‘breakthroughs’, are marginal and might not be clinically meaningful to patients, despite rapidly escalating costs,” says Courtney Davis of Kings College London (KCL) and the lead author of the study.
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Editors’ note of caution

Editors of the BMJ noted that the study was limited by the EMA’s“incomplete and variable” reporting of clinical studies, which contributed to the “possible overestimation of the proportion of drugs that offer survival or quality of life benefits”. They further suggested that the researchers did not consider the “appropriateness of clinical trial design”, which affects patient outcomes, and they also failed to take into account the “negative studies” for the indications they were studying.

Randomized controlled trials

Paradigm shifts in science, rapidly changing technologies, the increasing influence of patient advocacy groups and economic pressures on pharmaceutical companies are conspiring to drive change in randomized controlled trials (RCT), which were introduced 70 years ago to reduce bias when testing for a new treatment. RCTs have reshaped medical knowledge and practice and have become the “gold standard” means to assess the clinical efficacy of new or improved cancer therapies. In such procedures participants are randomly assigned to receive either the treatment under investigation or, as a control, a placebo or the current standard treatment. The randomization process helps ensure that the various groups in the study are identical across a number of relevant variables such as age, gender and socioeconomic status. This minimizes the potential for bias. Despite their strengths, only a modest percentage of therapies successfully navigate the regulatory minefield of RCTs from early stage to final approval. It takes between 10 to 15 years for a drug to pass through all the development stages and become approved for prescription. Only 5 in 5,000 drugs that enter preclinical testing progress to human testing, and only 1 in 5 of these is approved for prescription in clinics. The cost of developing a drug that gains market approval is estimated to be about US$2.6bn.

Enhanced understanding of cancer biology

One of the main limitations of cancer care has been our understanding of the biology of the disease, but this is beginning to change. Over the past 2 decades, oncologists have witnessed significant advances in our understanding of cancer biology and major breakthroughs in a number of therapeutic areas, which impact on drug targets and drug development. For example, next generation genome sequencing has increased the application of more robust models for different types of cancers. Cancer immunotherapy has captured the attention of scientists and has become a significant focus for drug delivery, and the development of genome editing technologies such as CRISPR Cas-9 have significantly impacted the direction and progress of nonclinical anticancer drug development.

Personalized medicine approaches have led to significant changes in the way oncology is practiced. Clinical and translational research is adapting to a rapidly changing environment with the intention to effectively translate novel concepts into sustainable and accessible therapeutic options for cancer patients, but not without significant challenges. Some of which are described by Axel Walther a medical oncologist and Director for Research in Oncology at University Hospitals Bristol, see video below. “If we combine patients in clinical trials with the concept of personalized medicine we start to add a lot of variables. This is because we want to target a novel treatment to the individual cancer of a specific patient. The challenge is to find that patient for whom the specific treatment is appropriate. If you have a treatment that addresses a specific abnormality you need to find all the patients with that abnormality. This is relatively easy if it’s a common abnormality but significantly more difficult if the abnormality isn’t common,” says Walther.

Pressures to change RCTs

Such scientific advances have shifted the emphasis of cancer treatment from histopathologically based methods (the microscopic examination of tissue in order to study the manifestations of disease) to molecular and genetically based treatments, which has significantly improved our understanding of disease processes and advanced drug development. Technologies, which use high-throughput screening of a number of potential target molecules are significant additions to our investigational medicinal product portfolio. Further, enhanced big data assets benefit from enhanced high volume, high velocity, high variety processing and interpretation and increasingly provide new and significant opportunities to conduct large-scale studies with many of the benefits of RCTs but without the expense. Big data techniques also allow for the study of rare cancers effecting small populations, which are often excluded from RCTs because of cost and other constraints. Such scientific and technological advances, together with the rapid expansion of the portfolio of therapeutic modalities, which can be used in various combinations to improve clinical outcomes, challenge traditional RCTs. Further, the costs and increasing complexity of RCTs means that promising drug candidates are sometimes abandoned for economic or logistical reasons rather than for their efficacy. For these reasons regulatory bodies, including the EMA, support changes in RCTs and are encouraging ‘adaptive clinical trials”.

Adaptive clinical trials

Adaptive clinical trials can be used in every phase of drug development. Rather than wait until the end of the trial to analyse data, adaptive trials accumulate and analyse data during the trial period and use results to change the actual direction of the trial. Adapting trials in this way is expected to reduce risks for both patients and pharmaceutical companies, particularly at challenging decision-points, such as dose selection. Significantly, adaptive trials can reduce the total number of patients required to obtain results. This, cuts cost and alleviates time constraints on sponsors, researchers, monitors, and trial sites and increases the capacity of the entire clinical development system. Notwithstanding, a concern is that data from such studies tend to be challenging to provide definitive answers.

Takeaways

Researchers drew attention to the fact that a significant number of cancer drugs become available in the UK without evidence that they significantly extend life. The slow pace and the eye-watering costs of traditional RCTs are increasingly being challenged by pharmaceutical companies, governments, scientists, patient advocacy groups and regulators. Fuelling such challenges is the unprecedented pace of change in our understanding of cancer biology, which has significantly influenced drug development and the modalities of treatments. New science is positioned to transform medicine beyond our recognition. But the science itself and the process by which it is transformed into useful medicine collide with RCTs.

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