PD MED is one of those big multicentre clinical trials that seems to have been around forever. In case you thought the study had long since been forgotten, PD MED reared its head again recently with the publication of the full trial results [1].

PD MED, for those of you not familiar with these acronyms was a long-term comparison of L-dopa, dopamine agonists and monoamine oxidase B inhibitors as first-line treatment for Parkinson's. Over the course of nine years, the study recruited 1,620 patients and randomised these to one or other therapy. Motor function was assessed using PDQ 39 and quality of life usingthe EuroQol EQ-5D generic quality-of-life measure. The study started recruiting in 2000 and finished in 2009. It is a measure of the scale and longevity of the study that it involved what seemed like every hospital in the country. And the number of listed investigators is in the hundreds. Some are dead. With a study of this length, there is significant attrition of investigators as well as subjects.

So, when you conduct a study on the scale of Normandy landings, you would hope that the results would be pretty ground shaking. The principal finding of the study was simple: Despite 50 years of research, neither of the two main alternative classes of drug (dopamine agonists or monoamine oxidase B inhibitors) match L-dopa in terms of symptom control and quality of life.

That's it. After 50 years, L-dopa is still the champ.

Worth the wait? Well, probably not if I'm honest. Not that there was much of a wait anyway since the results have been more or less public knowledge for a while. And in any case the principal conclusion is not entirely unexpected.

So where does that leave us? To my mind there are essentially two ways in this. On the one hand, and taking a rather negative stance, one could easily espouse the view that the results amount to very pretty strong indictment of the pharmaceutical industry collectively. Despite all the fancy technology and brilliant minds applied to the task, they have been unable to beat a drug that is half a century old. Or even match it. You wonder what they've been doing with the time.

On the other hand, look at it this way. L-dopa, despite its unquestionable efficacy, especially in the early stages, is a drug beset with long-term issues. Often dyskinesias can limit its clinical usefulness, especially in later stages of the illness. So L-dopa may still be the champ, but he is ageing fast and none of the young pretenders is ready to jump the fence.

For a drug company, that's not a bleak landscape. It's the field of opportunity.

Read the abstract from The Lancet here

Jon Stamford