Friday 17 October 2014

Coldzyme: a result of real science being left out in the cold

There’s no getting away from it, folks. Its sniffle season. For the next 6 months or so, the sounds of sneezes, coughs, and millions of noses being blown will echo throughout the nation.

We all know by now that the common cold is a virus. We all know that there is no cure. We also all know that, although you feel like crawling into a small dark warm cave and dying at the time, its usually much better after a few days, and it goes away of its own accord. Cold and flu remedies do nothing to actually get rid of your cold- they are there to make you feel better during it, although many of them are actually irrational combinations of products in shiny boxes with a redonkulously high price.

It is often said that if someone did come up with a cure for the common cold, they would be millionaires. I was, therefore, surprised to read this week in Chemist + Druggist magazine that indeed, the first ever product to not only treat the symptoms but to act on the virus itself was winging its way to pharmacy shelves as we speak. Really? Because blimey charlie, if that's the case, then this product should be Big News. 

Image source: http://www.sourcewire.com/news/84612/by-cod-now-your-plate-of-fish-chips-could-stop

The product is ColdZyme, a mouth spray that costs £8.99 for 20mLs. Seems a pretty fair price to pay for a product which claims to cure the most prominent infectious disease in the western hemisphere. It seems odd, though, that instead of this marvellous scientific breakthrough being plastered all over the media and medical literature, the article announcing it is tucked away quietly in a barely read corner of a trade journal.

What is this breakthrough, miracle product that will powerfully break down viruses? Well, an enzyme called trypsin. An enzyme that already merrily and plentifully kicks about in your digestive system, breaking down proteins. An enzyme which, for the purposes of this product, is inexplicable being derived from cod (which has meant that I have had to resist the urge to refer to it as somewhat fishy.) An enzyme which should be stored at temperatures of between -20 and -80 degrees Celsius, to prevent autolysis. Now, I've seen some fancy medicine packaging in my time, but never a simple mouth spray bottle that can manage such cold chain storage feats. So, if trypsin really is present in this product, then it seems fairly likely that its going to be inactive, unless the manufacturers have found a way of warping room temperature. Or you happen to be in Winnipeg in the middle of winter.

Medicine vs. Medical Device
The manufacturers make some really very extraordinary claims on their website, including one textbook example of special pleading. Their product, they state, isn’t a medicine. It’s a medical device, because it has no systemic effect. They then of course go on to helpfully tell us about the systemic effect it has:

“The medicines currently on the market only treat the various symptoms of a cold. ColdZyme treats the cause of the symptoms – the virus itself – and thus works both preventively against the common cold and shortens the duration of illness if you have already been infected.”

Right. So in the same breath, they are claiming that the product only forms a barrier, no more. But then they are also claiming that this barrier affects the ability of the virus to produce illness if you are already infected- viruses which are already through that barrier and inside your body. Come on, Enzymatica, you can’t have it both ways.

The Evidence
All these claims are backed up by evidence, right? Well, there is a tiny trial performed on only 46 people, which isn’t published anywhere. I can’t say whether or not it is a well designed trial, because I can’t see it in full, so to be honest, we pretty much have to just discount it. What we can do, however, if have a look to see if there is any other decent published information looking at the effect of trypsin on the cold virus. So I turned to the medical databases Medline and Embase, to trawl through the published medical literature. 

I did find one experiment which looked at the trypsin sensitivity of several human rhinovirus serotypes(1). And this appears to have found that viruses are only really susceptible to trypsin when there have been exposed to low pH, followed by neutralization- something which wont have happened to your common or garden cold viruses. I couldn’t find much else suggestive of a clinically significant antivirus action of trypsin.

The practicalities
This isn’t a simple, one-off- couple of sprays and away flies your cold sort of product. You have to use it every two hours, as well as after you brush your teeth and before you go to bed, and you have to continue this “until your symptoms are relieved”. That’s one hell of a regime. I have difficulty remembering to use medicines twice daily, never mind every two hours. I’ve never used this product, but I’d imagine that if it really does leave a “barrier” coating in your mouth, its a pretty unpleasant sensation. I can’t imagine many people sticking closely to these dosage instructions, and if the mechanism of action is as the manufacturer’s claim, skipping doses would cause the product to fail (if, indeed, it works in the first place)

We are also directed to “Start using ColdZyme® as soon as possible when you detect symptoms of a cold.”. Now, those of use who suffer with cold sores who have ever used aciclovir cream will know that this is often easier said than done- you probably haven’t got the stuff in the house, or at work, and by the time you’ve managed to get your hands on some, its already too late- your cold sore is out loud and proud, and using the drug will be pointless. Its likely that the very same thing will apply here. And remember that the incubation period for a cold is about 2 days- so the virus will already be cosily settled into your body before you even know about it. Its therefore completely ludicrous that this product claims to be able to reduce the length of a cold simply by forming a barrier.  

I know it can be used as a cold preventative, but how many people who feel completely fine are going to remember to use the product every two hours, every day, for the entirely of the cold season?

To Summarise
So, do I think there is scientific evidence to back up the extraordinary claims being made by ColdZyme? I might do when hell freezes over. Or at least when some decent trials are published, which might take just as long.  Do I think that this product should be sold through pharmacies? Absolutely not- this isn’t, if you ask me, real medicine. This is pure pseudoscience, trying its best to fool you into buying real medicine. Do I think lots of people will buy this, use it once or twice, then leave it to languish in their bathroom cabinet? Absolutely.

Here’s the problem though: this stuff will appear on the shelves of pharmacies all over. The pharmacists wont have a clue what this stuff is, and because they are really busy and probably quite tired at the end of each day, they wont be able to do the sort of evidence review I have managed to squeeze into a quiet moment. So they’ll get asked about it, and they’ll sell it. Some people will buy it and will feel better after a few days, and will think that the spray has made them better, forgetting that colds are self-limiting anyway. A customer might come back in the pharmacy one day, and say something like “hey, that new-fangled spray got rid of my cold!”, and the pharmacy staff will end up making recommendations on the basis of customer feedback and anecdotes, rather than on the basis of rational, scientific evidence. In my eyes, this really is a shame, and by selling this sort of nonsense, we really are cheapening our profession, and we're causing our customers to waste their money. 

If patients ask me about it, when I’m working behind the counter, I’ll tell them something along the lines of: “there’s no evidence or logical way that it works. It seems to be a bit of an expensive gimmick, with no decent basis to it. You’ll feel horrible with your cold, but it will start to go away of its own accord, I promise. In the meantime, you’d be much better off looking after yourself, having plenty of fluids and rest, and taking paracetamol according to the packet.”

Hxxx