United Therapeutics (UTHR 1.93%) has once again received a rejection from the FDA for its oral Remodulin for pulmonary arterial hypertension. In this video, Motley Fool health-care analyst David Williamson tells investors why this resubmission may have been too soon, what the company would need to do before the next resubmission to have a chance at approval, and who the hidden losers are in this rejection.