You are the Regulatory Affairs Manager at a small biotech company that only has one drug approved. That drug, however, is believed to also treat another indication based on recent clinical study data. Senior Management wants to promote this drug for this new off $-$ label use but your boss is aware that there are requirements around off $-$ label promotion and has asked you to draft a memorandum explaining what those requirements are.

Please draft a memorandum to your boss regarding the requirements around off $-$ label promotion and use case law to support your answer.