The field of cancer treatment has seen many exciting breakthroughs in recent years, most notably immunotherapy, which has emerged as the new treatment of choice for advanced metastatic melanoma, the most dangerous form of skin cancer. In particular, some patients who received immunotherapy drugs such as ipilimumab through clinical trials are still in remission more than a decade later. In addition, a number of targeted drugs such as olaparib, which has been shown to extend life in advanced ovarian cancer patients with a particular genetic mutation, have become newly available.
As a result, many cancer patients are understandably perplexed when their doctor says they cannot prescribe these new medicines for them – but there are a few reasons for this.
Many of these medicines are specific to particular characteristics of individual tumours. As an example, immunotherapy tends only to work against so called immunologically “hot” tumours, when a patient’s immune system is already actively trying to fight the cancer, even if it’s failing. If your immune system is completely blind to your cancer, immunotherapy is not likely to have an effect.
In addition, the cancer disease spectrum varies hugely, with solid tumours such as lung cancer requiring completely different treatment regimes to cancers such as leukaemia and lymphoma that don’t form tumours. “Different types of cancer behave very differently to one another, so you would use different ranges of treatments to treat each of those diseases,” says Martin Ledwick, head information nurse at Cancer Research UK (CRUK). “The type of treatment all depends on the type of cancer someone’s got, the stage it’s at, and how big it is.”
Right now, immunotherapy is making a big difference for some people with advanced melanoma under the NHS, and it can also be useful for treating lung cancer as a second line treatment following chemotherapy. However, it won’t be clear if it’s suitable for other cancers until scientists have accumulated evidence through large clinical trials that suggests it can make a difference.
This is because for many cancers immunotherapy may not help. It may still be that tried and tested approaches offer the best hope of a cure or of prolonging life for a great number of patients.
“We get a lot of calls to our helpline from patients describing their situation and asking for immunotherapy, and you look at their particular case and say: ‘To be honest, we know what works for you,’” Ledwick says. “We don’t know whether immunotherapy will work at all for your cancer yet, so you’d be better off going down the tried and tested route of surgery, radiotherapy and chemotherapy. Nonetheless, it is worth having an open and honest conversation with your consultant about your treatment options so that you are as informed as possible.”
In addition, cancer specialists point out that while reports in the media may describe the promise of new experimental treatments, there are reasons why they are not yet available. If the research described is entirely based on animal models, then scientists still have little idea as to whether it will work safely and effectively in humans, and it may be many years before funding can be raised for a phase one clinical trial.
Even if a new treatment has been through clinical trials, it still has to pass through two further stages of approval before oncologists can prescribe it for patients on the NHS: licensing via the European Medicines Agency (EMA) and a National Institute for Health and Clinical Excellence (NICE) recommendation.
Because the recommendation from NICE takes time, oncologists can still legally prescribe a drug with EMA licensing alone, but the question is whether they can obtain NHS funding for it so that it’s free for the patient. If a case is particularly unusual, then there are special means by which oncologists can apply for funding for a drug awaiting NICE approval. “This is in very unusual circumstances,” says Ledwick. “The key thing for people to understand is that you usually get what you need on the NHS. The rationing that people think is taking place isn’t nearly as widespread as they believe.”
The need for the various layers of approval before a treatment becomes available on the NHS is typically due to the risks associated with new medicines, and the need to assess how safely and effectively their side effects can be managed. “With immunotherapy for example, the drugs work by overactivating your immune system, and so their side effects can be serious for some people,” says Prof Alan Melcher, a CRUK-funded scientist who researches immunotherapy at the Institute of Cancer Research. “People can develop liver or lung inflammation, and even symptoms of auto-immune type diseases. Some people can get quite severe skin reactions to some of the new immunotherapies.”
Because many new medicines are often described as “targeted”, some patients assume this means the treatment will only go to the cancer, and will be without side effects or much risk. In reality, it means that the treatment is designed to recognise certain proteins that the cancer is producing, but these proteins are usually still produced by healthy cells, just to a lesser extent. “You’re still going to experience some side effects, just not the same side effects as you’d get with chemotherapy for example,” says Ledwick. “Quantifying the risk involved is why approval can take time.”
One way for patients to get access to treatments awaiting approval is by joining a clinical trial. “On a trial you’ll be closely monitored by a team of specialists and nurses,” says Melcher. “There are a number of trials taking place looking at combination therapies, particularly those that could enhance the effectiveness of immunotherapy – combining it with virus treatment, for example – which appears to be a promising way of making some tumours more susceptible to immunotherapy. But these treatments are still some way off from being available on the NHS.”
CRUK offers a cancer helpline where expert information nurses such as Martin Ledwick answer questions about cancer in confidence, 9am to 5pm Monday to Friday, on 0808 800 4040; plus an interactive community discussion forum, Cancer Chat; a dedicated About Cancer section of their website, providing clear information about cancer, its treatment and implications; and a cancer clinical trial database – so no question you have about cancer goes unanswered
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