Short of breath

United Therapeutics Corp. (NASDAQ:UTHR) fell $8.85 (18%) to $39.91 on Wednesday after its oral treprostinil again failed to beat placebo in a Phase III trial as an add-on therapy for pulmonary arterial hypertension (PAH). Undaunted, the company still plans to submit an NDA in 1H12 for the compound as monotherapy based on a separate Phase III study.

The stock finished the week off $8.70 to $40.07...