Pfizer got an approvable letter for SelzentryTM (maraviroc) in June, 2007. Yesterday, the FDA announced approval for the drug. The EMEA gave approval in July.
SelzentryTM is a first-in-class oral compound – a CCR5 antagonist – the first such development in a decade. According to the Pfizer release SelzentryTM "blocks viral entry into white blood cells, significantly reducing viral load and increasing T-cell counts in treatment-experienced patients infected with a specific type of HIV."
Interestingly, there was not a word in the press release about the resolution of issues with respect to the approvable letter that led to the eventual approval of the drug. Therefore one is left to speculate as to the reasoning behind the FDA action.
In looking back over the summer of releases, one would notice that this is the first time that the drug was named as SelzentryTM, rather the press release announcing European approval referred to the name Celsentri® which is the name that will be used for the product outside of the U.S.
While the company press release regarding the approvable letter did not state the reasons for the approval letter specifically, there was this sentence – "We continue our discussions with the FDA to address outstanding questions and finalize the product labeling as soon as possible. " (emphasis my own). The release used only the generic name – maraviroc.
One might speculate therefore that the hangup with the FDA that the issuance of an approvable letter for a product that had received an accelerated approval designation was based on the name. Perhaps they did not like Celsentri® and so now we have instead SelzentryTM –
Ah – asks Shakespeare – what’s in a name?
Interesting how the FDA might hold up an approval over a naming issue. My sense is that the agency is frequently concerned about a name that might confuse consumers (or doctors) — for instance, if it’s too similar to that of another prescription drug. I was told that’s why Genentech had to rename its psoriasis drug, which was originally called Xanelim, to Raptiva.
As for Selzentry, I was most intrigued by the fact that it’s just become one of a small number of drugs that can be considered “personalized medicine” by virtue of the fact that it’s paired with a diagnostic. I wrote more about that at the link below:
http://venturebeat.com/2007/08/08/personalized-medicine-takes-a-tiny-step-forward/