CANCER OLD DRUGS EXPENDITURE
Why should older drugs have seen such a big increase in expenditure? The answer lies in how drugs are licensed and then subsequently used. If we look at figure 13 to illustrate the breakdown of cancer therapy, we can see that around 40% of patients develop advanced cancer at some stage, and most of whom will ultimately die from the disease. New drugs are generally tested initially in this group of ultimately incurable patients with limited options. In breast cancer, for example, only a minority of patients dies from the disease and hence expenditure on a newly licensed, the end-stage drug will be relatively limited. However, if a drug works well in this group, it will often work better in earlier patients with potentially curable disease at high risk of relapse after their initial therapy. This group makes up around half of the patients who end up with advanced disease. Trials of successful end-stage drugs will thus take place in these patients and if successful the drug will ‘migrate’ into the earlier disease group.
This process is well illustrated by the Herceptin (trastuzumab) story. The drug was shown to prolong survival in advanced breast cancer in 2002. From the beginning, Herceptin has attracted huge publicity. The novel nature of the treatment rapidly became known amongst breast cancer patients leading to a clamour to enter the trials. So great was the demand that a lottery for trial entry had to be set up for interested eligible patients. After the drug obtained a licence, its high price (around £30,000 per year) led to restricted access in the UK and a different sort of lottery – the post-code lottery of UK cancer funding – began for a different group of women. The subsequent highly vocal campaign by women successfully overturned the restrictions but also set a precedent for other groups seeking access to expensive therapies that still bedevils purchasing authorities in the UK in particular.
Subsequent trials in earlier disease showed in 2006 that if given to women with the early high-risk disease after surgery, Herceptin reduced the chances of a disease recurrence by about half compared to previous therapies. The licence for Herceptin was thus extended to this earlier disease group the same year. Unfortunately, we cannot currently identify those who will relapse after surgery and radiotherapy. As most women in the early, high-risk group were already cured by standard therapy, the numbers eligible to receive the drug increased hugely (about four-fold in the UK) – all patients at risk have to be treated, not just those destined to relapse. Following a vocal campaign by women with the disease, the drug was made available on the NHS to all eligible patients.