Second Potassium Chloride Oral Solution Approved by FDA – Will Enforcement Action follow?


On August 19, 2015, the FDA approved a second 505(b)(2) drug application for potassium chloride oral solution, a potassium replacement therapy typically for patients taking potassium-depleting diuretics.  Previous to this approval, FDA approved another 505(b)(2) application for the drug on December 22, 2014.

Prior to that date, there were a number of marketed unapproved prescription drug products for potassium chloride oral solution on the market as “grandfathered” drugs or “DESI similar and related” drugs.  The market for potassium replacement therapy is rather large and, while there are numerous approved solid oral dosage forms available in the marketplace, many patients cannot take those products for various reasons.

The FDA’s Compliance Policy Guide on Marketed Unapproved Prescription Drug Products (here) outlines FDA’s enforcement priorities and notes that FDA will typically not take action against unapproved versions of prescription drug products after approval of an NDA for the same product, unless the firm receiving NDA approval can supply the entire market for the product.  In addition, FDA has indicated that enforcement action may be delayed until such time as healthcare professional can switch their patients to the approved version of the product.

The listing of enforcement actions FDA has taken since its 2006 push to removed unapproved prescription drugs from the market does not list potassium chloride oral solution products (here). We wonder if this latest approval will spur the Agency to commence enforcement action against the unapproved versions of this specific drug product?

FDA has been marching along in its effort to remove unapproved marketed prescription drugs from the market since 2006 and has been very successful in reducing the number of unapproved drugs available to the public. The latest enforcement action was against unapproved ear drops on July of this year (here).  Prior to that action, it has been a while since FDA has taken action on a class of unapproved marketed prescription drug products.   Only time will tell, but one might think that this second potassium chloride oral solution approval may signal another enforcement action in the near future.