UPDATED: Pfizer's Penis-Straightening Drug Gets an FDA Approval

• UPDATE: Auxilium responds to this article, and denies there is any current intent to use the drug for penis curvature. See below.

BNET readers will remember that Pfizer entered a $75 million pact with Auxilium for the development of Xiaflex in December 2008. And while the pair are developing the compound for use to combat Dupuytren's contracture (where patients' hands contract into claws), everyone knows that the other potential use Xiaflex has is for Peyronie's disease, or curvature of the penis from a buildup of fibrous tissue in the shaft. You can see Auxilium has a trial ongoing here, and the drug in question, "AA4500," is the same as that used in the Xiaflex trials here.

With the drug now heading to market, the question now is how much of the drug's sales will be for the off-label Peyronie's indication? I'm betting not much: Even though the drug works in straightening rats' tails it must still be administered by injection at the site of the organ, and that can cause bruising.

An Auxilium representative denied that the drug would be used off-label for Peyronies, and added that there were "multiple errors" in this item:

First, XIAFLEX is not Pfizer's drug â€" it's Auxilium's. Pfizer is our marketing partner only for Europe. Second, and most importantly, XIAFLEX just received FDA approval as the first nonsurgical treatment for Dupuytren's contracture and that's the drug's only approved indication. Although being studied in Peyronie's disease, we only announced Phase IIb data in December and are nowhere near a point to grant that indication. To suggest the possibility of off-label use for Peyronie's is reckless and potentially damaging.

• Related:
• Pfizer's Penis-Straightening Drug May Cause "Swelling, Redness and Bruising"
• FDA Gives Pfizer's Penis-Straightening Drug Priority Review
• Pfizer to Sell Penis-Straightening Drug