Salix Pharmaceuticals CEO Carolyn Logan said on a conference call with analysts Thursday that a federal investigation into the Raleigh's company's sales practices could "go on for quite some time."

"It's usually not a short process, as we've been told," she said.

Salix announced last month that it has received a subpoena from the U.S. Attorney's Office for the Southern District of New York requesting documents related to the company's sales and promotional practices for three of its drugs.

The company received the subpoena on Feb. 1, according to its regulatory filing.

The drugs involved are Salix's best-selling Xifaxan, as well as Relistor and Apriso.

Salix said in its filing that it is in the process of responding to the subpoena and intends to cooperate fully with the investigation.

Salix Pharmaceuticals reported late Thursday that revenue increased 28 percent in the fourth quarter and was up 36 percent for the full year.

The Raleigh company had revenue of $198.2 million for the quarter, which equaled the consensus among Wall Street analysts who cover the company.

Excluding the loss of extinguished debt and non-cash adjustments, net income for the quarter was $51 million, or 81 cents per share. That beat the 78 cents that Wall Street analysts forecast.

Salix, which sells drugs to treat gastrointestinal ailments, had revenue of $735.4 million last year. The company forecasts revenue of $920 million in 2013, a 25 percent increase.

Analysts with RBC Capital Markets have rated Salix Pharmaceuticals outperform in their first research note on the Raleigh company.

RBC initiated coverage with a target price of $53 for Salix shares. The stock is currently trading around $46 per share.

"While the company experienced some pipeline setbacks over the past two years, we believe these are already well reflected in the stock price," the analysts wrote.

Salix sells drugs to treat gastrointestinal ailments. Much of the RBC analysts optimism about the stock relates to their belief that revenue from Xifaxan, Salix's best selling drug, will grow significantly in the future.

Salix Pharmaceuticals reported late Wednesday that revenue increased 27 percent in the third quarter.

The Raleigh company had revenue of $185.1 million for the quarter, which was below Wall Street estimates of $187.6 million.

Excluding the loss of extinguished debt and non-cash adjustments, net income for the quarter was $59.7 million, or 95 cents per share. That handily beat the 70 cents that was the consensus among Wall Street analysts who cover the company.

Salix sells drugs to treat gastrointestinal ailments.

Salix Pharmaceuticals announced Wednesday that federal regulators have extended the review period for Crofelemer, the Raleigh company's drug to treat diarrhea in patients with HIV or AIDS.

The Food and Drug Administration was scheduled to make a decision on Salix's new drug application for Crofelemer on Wednesday, but the company now expects a decision by the end of the first quarter.

Salix submitted the drug to the FDA for review in December and it was later granted priority review. The FDA grants priority reviews to drugs that offer major advances in treatment or which provide treatment where no adequate therapy exists.

Crofelemer's 125 mg tablets would treat diarrhea in patients with HIV or AIDS who are on anti-retroviral therapy. Salix estimates that some 150,000 patients on the therapy experience chronic diarrhea, which can cause weight loss and complicate treatment.

Salix Pharmaceuticals reported late Wednesday second-quarter earnings that handily beat Wall Street estimates.

The Raleigh company had revenue of $181 million for the quarter, up 36 percent from the same period in 2011. Excluding the loss of extinguished debt and non-cash adjustments, net income for the quarter was $50.9 million, or 79 cents per share.

That easily beat the 54 cents that was the consensus among Wall Street analysts who cover the company.

Revenue from Salix’s best-selling drug Xifaxan, which is approved to treat travelers’ diarrhea and a rare liver condition, increased 34 percent in the quarter to $116.7 million. Salix now forecasts total revenue for 2012 to be $735 million, which would be a 36 percent increase over 2011.

Salix sells drugs to treat gastrointestinal ailments. The company’s stock dropped 13 percent in a single day late last month after Salix announced that federal regulators have requested additional clinical data for its application for Relistor, a drug that treats constipation in patients taking pain medicines.

Irina Rivkind, an analyst with Cantor Fitzgerald, upgraded Salix’s stock to a buy rating after the company’s earnings release on Wednesday. In raising her price target for the stock to $60 she said the stock fell more than expected after the Relistor announcement.

Salix shares closed up 75 cents at $45.74 on Thursday. The stock is down 4 percent this year.

Salix Pharmaceuticals stock dropped 13 percent on Monday after the company announced that federal regulators have requested additional clinical data for its application for Relistor, a drug that treats constipation in patients taking pain medicines.

Salix and its partner, Progenics Pharmaceuticals, seek to have Relistor approved to treat patients with chronic pain. The injected drug is currently approved only to treat patients with advanced illnesses who are taking opioid painkillers, which often cause severe constipation.

Salix said in a news release that it has requested a meeting with Federal Drug Administration officials to better understand the Complete Response Letter it received from the agency.

The letter is what the agency issues when its review process is complete and a drug application is not ready for approval.

Raleigh-based Salix bought the rights to Relistor in February 2011. The drug had just $16 million in worldwide sales in 2010, but Salix thinks the drug has the potential for peak annual sales of a billion dollars.

Salix shares closed down $6.94 at $46.25. The stock is down 3 percent this year.

Salix Pharmaceuticals reported late Monday that revenues increased 62 percent in the first quarter.

The Raleigh company had revenue of $171.1 million for the quarter, up from $105.9 percent in the first quarter of 2011. That beat the $168 million that was the consensus among Wall Street analysts who cover the company. Net income for the quarter was $10 million, or 15 cents per share.

Salix sells drugs to treat gastrointestinal ailments. Revenues from its best-selling drug, Xifaxan, which is approved to treat travelers' diarrhea and a rare liver condition, increased 40 percent in the first quarter to $112.9 million.

The company said in a statement that it plans to increase the size of its sales force from 160 to 195 over the next several months. The sales force focuses on building up relationships with gastroenterologists, colorectal surgeons and hepatologists. 

“Our core business is strong and growing,” CEO Carolyn Logan said. “In the near term we believe we can generate $1 billion in revenue in 2013.”

That belief, she said, is based on Salix winning regulatory approval in July to expand the allowed uses for Relistor, a drug that treats constipation in patients taking pain medicines.

It doesn’t include potential revenues from Salix winning approval to market Xifaxan for treatment of irritable bowel syndrome. At the FDA's request, Salix has begun a trial to test how patients would respond to repeated use of the treatment.

Salix shares closed Monday up $1.11 at $49.60. The stock is up 4 percent this year.

Salix Pharmaceuticals announced Monday that federal regulators have extended the date by which they expect to complete a review of Crofelemer, a potential drug treatment for HIV-associated diarrhea.

The Raleigh company said the review date has been extended from June 5 to Sept. 5. The Federal Drug Administration did not request additional studies.

The FDA granted Crofelemer priority review status in February. Such reviews are granted to drugs that offer major advances in treatment or which provide treatment where no adequate therapy exists.

Crofelemer's 125 mg tablets would treat diarrhea in patients with HIV or AIDS who are on anti-retroviral therapy. Salix estimates that some 150,000 patients on the therapy experience chronic diarrhea, which can cause weight loss and complicate treatment.

A second Salix drug, Relistor, also had its FDA review date pushed back last week. Relistor treats constipation in patients taking pain medicines.

Salix Pharmaceuticals reported fourth quarter earnings late today that beat Wall Street estimates thanks to robust sales of its best-selling drug Xifaxan.

The Raleigh company reported revenue of $155.2 million for the quarter, up 31 percent from the same period in 2010. Net income, excluding certain charges, for the quarter was $76 million, or $1.18 per share.

That beat the 93 cents per share that was the consensus among Wall Street analysts who cover the company.

For the year, Salix reported revenue of $540.5 million, up 60 percent from 2010.

Salix sells drugs to treat gastrointestinal ailments. Xifaxan is approved to treat travelers' diarrhea and hepatic encephalopathy, a rare liver condition.

Xifaxan revenue for the quarter was $107.2 million, up 29 percent from the same period in 2010. Xifaxan revenue for the year was $371.7 million, up 48 percent.

In a statement, Salix's chief financial officer, Adam Derbyshire, said the company expects revenues in 2012 to increase 36 percent to about $735 million.

Salix shares closed today up 3 cents at $46.14. The stock is up 38 percent over the past year.