Tuesday, 6 December 2016

Aspirin as an anti-metastatic drug - in 1977

Working on drug repurposing often involves an element of historical research. Drugs like cimetidine, nitroglycerin and propranolol have been around for decades and there’s a lot of good data that we can extract from old articles, clinical trials and retrospective studies. One of the best known examples of old drugs is aspirin - which is attracting a huge amount of attention from clinical researchers in oncology. There is a huge literature on aspirin, with much more on the way as clinical trials are designed, run and reported.

One of the most intriguing things about aspirin is the data that suggests that it might work as an anti-metastatic agent. There is data that shows that aspirin may be effective in reducing the risk of metastatic spread in breast, prostate and colon cancer (for example this recent meta-analysis reported a relative risk of metastasis of 0.77 with aspirin).

That we’ve known about the anti-cancer potential of aspirin for a long time isn’t a surprise – but I have to admit to being surprised to come across a paper from 1977 arguing the case that aspirin might be an effective anti-metastatic drug. The paper is Aspirin for reducing cancer metastases? by Henschke, Luande and Choppala (J Natl Med Assoc. 1977 Aug;69(8):581-4). The paper is available open access (here), and while the data is old, the arguments it makes are still vital and relevant. It really begs the question, how is that things haven’t moved forward more quickly? And, more crucially, how can we make sure that things move forward more quickly in the future. Not just for aspirin but for so many of the other old drugs that have good data in their favour.