Published a few days ago, the FDA draft guidance titled Quantitative Labeling of Sodium, Potassium, and Phosphorus for Human Over-the-Counter and Prescription Drug Products (here) discusses the FDA’s thinking on the standardization, proper format, and necessary information for the contents of these elements in OTC and prescription drug labeling.  Right now, labeling for OTC products is required to include information on sodium and potassium content (see regulations at 21 CFR 201.64 and 201.72).  This guidance includes recommendations for the inclusion of phosphorous content in OTC labeling as well as the content of all three elements in labeling for prescription drugs.  Recommended labeling would include the accurate milligram contents of all constituents, including active and inactive ingredients, in product formulations.

The reasoning, says the FDA, is that “[H]ealth care providers generally recommend that patients with certain clinical conditions—such as heart failure, hypertension, or chronic kidney disease—restrict dietary intake of sodium, potassium, and/or phosphorus.  Quantifying these constituents in drug product labeling would provide health care providers and patients with information that will help them account for the amounts of these constituents present in a patient’s daily drug regimen when determining an individual’s total daily intake.  Quantifying these constituents in drug product labeling as recommended in this guidance may also allow health care providers and patients to select drug products with lower amounts of these constituents when such alternatives are available.”

The draft guidance describes how to revise labeling and provides an appendix with examples of how OTC and Rx labeling should look.  The Agency notes that a product containing less than 5 mg of any of these elements in the maximum single dose need not include this information on the label.  There are suggestions for rounding up the content of all three elements, and the Agency makes it clear that if firms elect to include the information for approved drugs, sponsors can make the changes at any time and provide the revised labeling in their next annual reports.  However, this filing strategy is predicated on there being no change in product formulation or other aspect of the filing that might require a supplement.

The FDA recommends that “[A]n applicant submitting a new drug application (NDA), an ANDA, or a biologics license application (BLA) that elects to include quantitative information on sodium, potassium, or phosphorus in product labeling must ensure that the labeling statement is accurate and is supported by information related to the drug product’s ingredients.”

The interesting part of this guidance, which, by the way, represents the Agency’s current thinking and does not establish legally enforceable responsibilities, is that once the FDA makes a recommendation to include additional information to support the safety of a drug product’s use outside of regulatory requirements, then it may be difficult for a company’s general counsel not to demand that the firm acts on the FDA’s recommendation, lest a suit arise because of patient injury if the information is not included.  This may be particularly true if any of these elements is at a higher level in a generic than the RLD upon which it relies or at differing levels in generic products referring to the same RLD.  Just a message of caution that firms may want to heed, especially in this litigious society.