Section 316.23 - Timing of requests for orphan-drug designation; designation of already approved drugs(a) A sponsor may request orphan-drug designation at any time in its drug development process prior to the time that sponsor submits a marketing application for the drug for the same rare disease or condition.(b) A sponsor may request orphan-drug designation of an already approved drug for an unapproved use without regard to whether the prior marketing approval was for a rare disease or condition. 78 FR 35133 , June 12, 2013