What the term “off-label” can mean there is that, again, when you studied it, you may not have combined those particular drugs. “Cocktail” means you're putting several drugs together in a treatment course; you may not have done a pre-market study or a clinical study on that, but they may be used in conjunction with each other, and that would be called off-label as well.
On May 1st, 2008. See this statement in context.