During a conference call the FDA expressed a concern relating to the potential for immunogenicity that might result from a possible interaction between calcitonin-salmon, the drug’s active ingredient, and chlorobutanol, the preservative that the company used in its formulation of the drug.
In response to the FDA rebuff the company said that no allergic reactions were observed in any of the clinical trials that it conducted on its formulation of the drug. The company now intends to engage in further discussions with the FDA to determine which, if any, additional data it can submit in order to gain approval for the product.