United Therapeutics Corporation ( UTHR - Analyst Report ) recently announced that the US Food and Drug Administration (FDA) has accepted its new drug application (NDA) for oral Remodulin (treprostinil) that was re-submitted by the company following the receipt of a complete response letter (CRL) from the FDA in Oct 2012. United Therapeutics is looking to get oral Remodulin approved for the treatment of pulmonary arterial hypertension.

The FDA is treating the resubmitted NDA as a complete, class 1 response and will respond to the application by Mar 31, 2013.

We note that United Therapeutics is facing a patent challenge for Remodulin (treprostinil) injection. Sandoz is seeking approval for its generic version of Remodulin (10 mg/mL). United Therapeutics has filed a patent infringement lawsuit against Sandoz. Remodulin, the key revenue generator at United Therapeutics, accounts for almost 50% of sales.

United Therapeutics currently carries a Zacks Rank #1 (Strong Buy). The company is well-positioned to gain share in the pulmonary arterial hypertension market. Remodulin continues to look very strong in both the intravenous (IV) and subcutaneous (SC) forms.

With the approval of Adcirca and Tyvaso, United Therapeutics has a varied range of therapies available for the treatment of pulmonary arterial hypertension. We believe the company’s pulmonary arterial hypertension product portfolio will drive strong top-and bottom-line growth.

Other players in the pulmonary arterial hypertension market include companies like Gilead ( GILD - Analyst Report ) and Pfizer ( PFE - Analyst Report ) among others. We believe competition will continue to increase with several companies working on bringing additional therapies to the market.

Another company that currently looks well-positioned is Valeant Pharmaceuticals ( VRX - Snapshot Report ) . Valeant is also a Zacks Rank #1 stock.