Posted by ed_uk on December 16, 2004, at 15:15:54
In reply to Re: Eszopiclone » ed_uk, posted by jrbecker on December 16, 2004, at 14:09:24
Hi JR!! :-)
Thank you very much for providing the link to the articles.
>The company postulates that due to Eszoplicone being a stereoselective (S) isomer of the zopliclone molecule, it is associated with greater efficacy and less side effects.
Zopiclone (Zimovane in UK) is a racemate, as a result it consists of 50% eszopiclone and 50% R-Zopiclone. Since R-Zopiclone is thought to be virtually inert, there doesn't seem to be any theory to support the manufacturer's claim that eszopiclone would cause any less side effects or be any more effective than zopiclone (which, I must add, I available as a nice cheap generic!!)
>eszopiclone IS more potent
It certainly is, but potency is not synonymous with efficacy. The fact that it is more potent simply means that a smaller dose will be needed to obtain the same effect.... this tells us nothing about the efficacy or toxicity of the drug. Paroxetine is a much more potent SSRI that sertraline yet it is no more effective, nor is it better tolerated. Hydromorphone is more potent mu-agonist than morphine but its efficacy and toxicity are virtually the same.
Sepracor, of course, are desperate for us to believe that a drug that can be given at a lower dose must be better... they are trying to fool the world!! Only if R-Zopiclone was proven to be toxic or detrimental to the therapeutic efficacy of eszopiclone would Lunesta have any advantage over the racemate RS-zopiclone (Zimovane).
As far as I know zopiclone is not available in the US. As a result, eszopiclone will be a potentially useful addition to your pharmacopoeia. Unfortunately, if it is at some point introduced into the UK, it won't be so useful to us :-(
Generic zopiclone in the UK...
Tablets, zopiclone 3.75 mg, net price 28-tab pack = £3.07; 7.5 mg, 28-tab pack = £4.34.
So, zopiclone 3.75 mg contain 1.875 mg eszopiclone.... and zopiclone 7.5 mg tablets contain 3.75 mg eszopiclone. I bet the new Lunesta tablets are more expensive!!
Kind Regards,
Ed.
poster:ed_uk
thread:428339
URL: http://www.dr-bob.org/babble/20041211/msgs/430362.html