7

I was using this spray meant to hasten recovery from the common cold. This study, sponsored by the pharmaceutical company that produces the spray, stated it reduced virus by 92%, and so shortens the duration of the common cold.

Meanwhile a doctor told me that these kinds of things don't work.

Does someone have some perspective on this? Is this a believable study? Was it well designed, and has it been duplicated?

If so, why wouldn't the pharmaceutical produced a certified and expensive drug instead of a no-prescription drug?

3

Looking at this from the perspective of an infectious disease epidemiologist, the kind of person who often reads (and occasionally runs) studies of this type, I'm skeptical. A number of reasons why:

  • The only results are a synopsis. More details and data are apparently available, but there is no manuscript, and their "Transparency Policy" has a lot of caveats in it.
  • It's not a peer reviewed study.
  • Their treatment protocol is oddly variable - 4 mandatory days plus a possible additional six days based on...?
  • Again, since they're not providing tables, this gets a little frustrating to try to consider, but their treatment arm is fairly heavily skewed toward women - they claim it's similar in the control arm, but they won't show you how similar.
  • They fail at their primary endpoint, being the mean number of symptoms reported between the treatment and control. The mean number of symptoms are about half-a-symptom less between the treatment and control arms, but the result isn't statistically significant, they do some statistical adjustment I'm a little skeptical of - because they don't describe it - and they end up using somewhat...loose...language like "was a strong trend in favour of Bisolviral®."
  • This is all based on patient self-report of symptoms, and interestingly, there's absolutely not an effect for self-reported assessment of efficacy between the treatment and control arms. Further, looking at viral load assays, there's also no biological evidence that anything is happening.

I can't find the specific language about the 92% claim you cite in your question, but my assessment of the overall evidence that this compound works would be "Faint and preliminary, at best".

  • Since the link said "Full text" I thought it had the full text, and not a synopsis of the result. The 92% claim is in the promotional material from the spray. Meanwhile I found some other "similar studies" (I think), and asked a more broad question. It's here, if want to have a look. Thanks! – Fernando César May 3 '15 at 6:48

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.