Cancer treatments are increasingly successful in managing the disease on a long-term basis. However, funding these drugs is becoming ever more expensive, writes Dr Gary Bolger
There is a sea change underway in the treatment of cancer, and the key to this has been the arrival of new types of drugs - drugs that work in different ways from traditional cancer chemotherapy. These new treatments use our increasing knowledge of the molecular biology of how cells work and how they communicate with one another.
Some of these drugs, such as the monoclonal antibodies Avastin and Herceptin, are already here and licensed for use in specific circumstances. Many others are in the pipeline and are expected to enter the market over the next few years.
An important feature of treatment with these new drugs is that, much like treatment of chronic conditions such as hypertension and diabetes, an increasing number of forms of cancer are becoming chronic, but manageable, long-term conditions.
In addition to cost, this development in therapeutics raises some challenging issues for medical insurers. In Britain, healthcare cover has traditionally paid for the treatment of medical conditions that respond quickly to treatment - socalled acute conditions. However, with some of the newer treatments, it is not yet clear just how long they will need to be used for maximum effect. With others, it is already clear that treatment is lifelong.
Health matters
When we are well and one of our cells dies, which they do naturally and as a matter of course, a neighbouring cell divides to replace it with a healthy new 'daughter' cell that should function normally.
However, in cancer, this process goes awry and the abnormal cells that are generated not only fail to function normally but they also carry on growing and dividing and, in turn, crowd out normal healthy cells. Some of the cancer cells may also break off from the initial mass (or neoplasm or tumour) and spread to other parts of the body - a process known as metastasis. Traditional cancer treatment, which generally involves surgery, radiotherapy and chemotherapy, has tended to be a gruelling experience for patients. This is particularly true for chemotherapy, in which the body is flooded with high doses of poison that kill not only cancer cells but also normal healthy cells, causing serious and unpleasant side effects including loss of white blood cells (which fight infections) and cells that make our hair.
An important development in cancer treatment has been the arrival of monoclonal antibodies. These are based on naturally occurring proteins that are a part of our immune system and which scientists have cleverly adapted to home in on and block the functioning of critical components of cancer cells or their blood supply.
Herceptin, for example, has been licensed for five years to treat metastatic breast cancer and recently had its licence extended for use in the early (or primary) stage of the disease. Herceptin works by stopping growth-triggering protein messengers from reaching certain cancer cells. It does this by attaching to receptors on the cancer cell wall and blocking the messenger that would normally bind to this receptor. By analogy, receptors are like small locks and the messenger proteins like small keys that fit into them. Herceptin sits on the lock - similar to putting Sellotape over the keyhole so that the key cannot fit.
However, this blockage is only temporary, so Herceptin needs to be given on a regular basis (every one to three weeks) to keep up its beneficial effect. This is why, in metastatic cancer, Herceptin is given for as long as it continues to control the cancer, which can be for many years.
Big hope
In primary cancer, clinical trials have reported promising results after use for one year, but the trials are continuing in order to see if patients benefit further from use over longer periods.
Furthermore, clinicians hope that, alongside the growth blocking effect seen in metastatic disease, Herceptin may aid the body's own defences in primary cancer so that they can deal decisively with the disease without the need for continuing use.
Not all monoclonal antibodies act directly on the cancer cells, however. In order to grow beyond a very small size, cancers need a blood supply to give them oxygen and nourishment. To obtain this they send out a signal or messenger to neighbouring blood vessels to stimulate them to generate a more extensive blood supply. Avastin, which is currently licensed for treatment of metastatic bowel cancer, attaches to this messenger and stops it reaching the blood vessels. Again, this effect is temporary and so Avastin needs to be given on a regular, continuing basis.
Cost of living
The cost of monoclonal antibody treatment ranges from £20,000 to over £80,000 per patient per year. These costs are usually over and above current therapy costs, and as more of these drugs become available we are likely to see them used in combination with one another. Clearly, paying for them is a big issue for healthcare providers throughout the world, regardless of how they are funded.
There are a number of reasons for the high cost. Drug companies invest vast amounts on research and development that, naturally, they wish to recoup, with the cost of bringing a new drug to market being around US$1bn.
There are also many hurdles to be crossed before manufacturers convince the regulatory authorities that a new treatment is safe and effective - a process that takes many years, involving laboratory tests and, for promising agents, clinical trials on volunteers. Unfortunately, many initially promising drugs fall by the wayside - in some cases because they cause harmful side effects.
Drug companies also want to maximise profits for the relatively short time that their patents last. Furthermore, monoclonal antibodies tend to be expensive to manufacture, and because of the highly technical nature of the production process there are unlikely to be significant efficiency gains in the short- to mid-term.
In addition to the costs of the drugs themselves, monoclonal antibodies need to be given intravenously under medical supervision and may need special investigations to look for side effects of treatment, like for example, heart failure in patients taking Herceptin.
It will not be easy to pay for these new drugs. For example, around 40,000 women in the UK are diagnosed each year with breast cancer, the great majority of whom have the early form of the disease. Around 8,000 of these women will have the aggressive so-called HER2+ form of the illness and will be suitable candidates for treatment with Herceptin.
However, the cost for treating those patients would amount to over £160m, which represents a sizeable proportion of total NHS expenditure on cancer drugs in 2005. And now that the European Medicine Agency has granted a licence for use of Herceptin in these circumstances - a view that the National Institute for Health and Clinical Excellence has endorsed - this massive expenditure is becoming a reality.
Herceptin costs around £25,000 a year per patient and, for early breast cancer, a year's treatment is currently being recommended. But this could be extended if further clinical trials demonstrate that even longer periods of treatment produce better outcomes. Similarly, Avastin, which costs around £70,000 a year and is currently licensed for treatment of metastatic bowel cancer, is expected to have its licence extended to include treatment of other forms of cancer in the near future.
NHS problem
It remains to be seen how the NHS will secure funding not only for these but also for other cancer treatments that look likely to gain their licences in the coming years. From a medical insurer's perspective there will inevitably be a long-term impact on pricing, and insurers are thinking carefully about how to manage these.
In the future, not every customer is going to be able to afford an all singing, all dancing policy and, to be successful, insurers will need to offer a clear range of cover that enables customers to choose plans that meet their needs - and budgets - for cancer care cover.
Dr Gary Bolger is head of medical policy at Axa PPP Healthcare
