In the light of the headlines over the past few weeks, the public could be forgiven for thinking that a cure for cancer is here.
The latest developments in immunotherapy are great news, of course, and offer hope to some where before there was none. But although they may offer a way of countering one of the major weapons of cancer cells – the ability to defend themselves by turning off the body’s immune system – they are not the universal panacea that everyone would like to believe.
Certainly the results of recent clinical trials have shown the potential for these drugs to extend the life expectancy of some patients with advanced lung cancers and melanoma – but only in some patients. Admittedly more than half showed a response to the combination of ipilimumab and nivolumab, but more than 40% did not, and the researchers have no idea why.
One of the most important factors in the developing field of precision medicine is the ability to predict who will benefit and who will not, so there is still a long way to go in that respect.
The treatment also induced some severe side-effects, including meningitis and hepatitis, and it is far too soon to say what the long-term effects of these drugs may be on the immune system.
And then there is the cost. Ipilimumab costs around £75,000 per patient; nivolumab, not yet licensed in Europe, is available in Japan at a reported cost of nearly £100,000 a patient.
At the same time as the breakthrough in immunotherapy was announced, the recently licensed ovarian cancer drug olaparib was rejected by the UK’s drug regulator NICE on grounds of cost and because it had not yet shown it extended life expectancy beyond existing drugs even though it was better tolerated. Any new palliative cancer treatment will be subject to similar scrutiny and the decision may not always go the way of the drug company and the patients.
Immunotherapy is certainly a milestone on the way to defeating cancer. But while we may have turned a corner, there is still a long and winding road ahead.
