UPDATE 1-FDA rejects United Therapeutics' oral hypertension drug again

* Rejects resubmission filed in February

* Co likely to conduct fresh late-stage trial - analyst

* Shares down about 6 pct in early trade

(Adds analyst comment) By Vrinda Manocha

March 25 (Reuters) - Biotechnology company United Therapeutics Corp said its oral drug to treat hypertension was rejected for the second time by U.S. health regulators, sending its shares down about 6 percent in early trade on the Nasdaq.

The drugmaker did not say it would quit pursuing a marketing approval for the tablet.

"We remain confident that oral treprostinil will play an important role in treating pulmonary arterial hypertension," Chief Executive Martine Rothblatt said.

The drug, treprostinil diolamine, was first rejected by the U.S. Food and Drug Administration (FDA) in October after it had failed to show statistically significant results in patients taking a six-minute walk test during clinical studies.

The company would probably conduct another late-stage trial for the drug as it had originally planned, Wedbush analyst Liana Moussatos told Reuters.

"After the first rejection,the company thought they'd have to do another late-stage trial and it would take four years before they could resubmit the marketing approval application," she said.

"They did some additional analysis and brought in some historical data and thought they would give it another shot."

The drug will not be approved before 2017 if the trial and the review takes four years.

United Therapeutics already has a treprostinil injection named Remodulin and an orally inhaled version Tyvaso on the market to treat pulmonary arterial hypertension, a disease characterized by abnormally high blood pressure in the pulmonary artery that carries blood from the heart to the lungs.

Moussatos said United Therapeutics did not need oral treprostinil to maintain its growth. She had earlier projected $399 million in peak annual sales for the drug, but had not included the oral variant in her model.

Remodulin, the company's lead product, accounted for $458 million in revenue last year, about half of United Therapeutics's net revenue. The company also sells Adcirca, an oral tablet to treat PAH.

Oral versions of drugs are usually preferred over other forms due to their ease of administration.

(Reporting By Vrinda Manocha in Bangalore; Editing by Sreejiraj Eluvangal)

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Keywords: UNITEDTHERAPEUTICS FDA/HYPERTENSIONDRUG

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