In any case, the letter then goes on to make some astounding claims, including [bold font in original letter]
The clinical profile of Lexapro and citalopram are distinct, as illustrated by the following:
- Lexapro is effective in the treatment of major depressive disorder (MD) and generalized anxiety disorder (GAD). In contrast, citalopram is not indicated for GAD, or for any other anxiety disorder. [citations were to the respective drug labels.]
- There is clinical evidence for the greater efficacy of Lexapro vs. Celexa
...among others. For a very nice analysis of why these claims are misleading, please read the full post at Health Care Renewal. My two cents on why the claims are misleading is as follows:
- Since its patent was running out, Forest opted to not seek FDA approval for any anxiety disorders. No study has ever compared the two compounds in treating anxiety. While true that citalopram is not FDA-indicated, this should not be taken as a sign that it would perform worse than escitalopram in anxiety. Indeed, across the class, SSRIs are efficacious (in the short-term, and not a lot better than placebo) for anxiety.
- The evidence cited to support the greater efficacy of escitalopram over citalopram is very weak. It comes from looking only at the few instances where escitalopram showed a very small advantage over citalopram and ignoring the great majority of the evidence that suggests equivalent efficacy of the two compounds. An excellent article by Svensson and Mansfield laid this issue to rest years ago. Here's what they said regarding Forest's prior advertising claims that Lexapro is more effective than Celexa:
"The advertising claims are not justified because they are based on secondary outcomes, non-intention-to-treat analyses and arbitrarily defined subgroups. The subgroup results are inconsistent. Methodological flaws in the trials could account for the differences found. Even if the differences claimed were real they appear too small to justify higher prices."
My thought is that the letter may have something to do with managed care policies, but it is also a stealth advertisement for Lexapro as being the most efficacious SSRI. After all, if it is "better" than Celexa, then maybe it is "better" than other SSRIs. Of course, this would not be the first time that something Lexapro-related was looking at the scientific evidence through rose colored glasses.