Glaxo Does a Deuterium Deal

| About: GlaxoSmithKline (GSK)

Well, there's someone who certainly believes in the deuterated-drug idea! GlaxoSmithKline (NYSE:GSK) has announced today that they've signed a deal with Concert Pharmaceuticals to develop these. There's a $35 million payment upfront, which I'm sure will be welcome in this climate, and various milestone and royalty arrangements from there on out. I know that the press story says that it's a "potential billion dollar deal", but you have to make a useless number of assumptions to arrive at that figure. Let's just say that the amount will be somewhere between that billion-dollar figure and... well, the $35 million that Glaxo's just put up.

Where things will eventually land inside that rather wide range is impossible to say. No one's taken such a compound all the way through development, and every one of them is going to be different. (Deuterium might be a good idea, but it ain't magic.) It looks like the first compound up for evaluation will be an HIV protease inhibitor, CTP-518, which is a deuterated version of someone's existing compound - Concert has filed paten applications on deuterated versions of both darunavir (WO2009055006) and atazanavir (WO2008156632). The hope is that CTP-518 will have an improved enough metabolic profile to eliminate the need to add ritonavir into the drug cocktail.

The company is also providing deuterated versions of three of GSK's own pipeline compounds for evaluation, which is interesting, since that's the sort of thing that Glaxo could do itself. In fact, that's one of the key points to the whole deuterated-compound idea: the window of opportunity. Deuteration isn't difficult chemistry, and the applications for it in improving PK and tox profiles are pretty obvious (see below). It's a good bet that drug company patent applications will hencrforth include claims (and exemplified compounds) to make sure that deuterated versions of drug candidates can't be poached away by someone else. This strategy has a limited shelf life, but it's long enough to be potentially very profitable indeed.

One more note about that word "obvious". Now that people are raising all kinds of money and interest with the idea, sure, it looks obvious. And I'm sure that it's a thought that many people have had before - and then said "Nah, that's too funny-sounding. Might not work. And besides, you might not be able to patent it.

And besides, if it were that good an idea

, someone else would have already done it. There must be a good reason why no one's done it, you know". Getting up the nerve to try these things, that's the hard part. Roger Tung and Concert (and the other players in this field) deserve congratulations for not being afraid of the obvious.