UPDATE 1-Retrophin shares soar after kidney drug deal

Fri May 30, 2014 3:18pm EDT

(Adds detail, updates shares)

May 30 (Reuters) - Shares of Retrophin Inc jumped as much as 31 percent on Friday, a day after the drugmaker raised its full-year revenue forecast following a deal to market a lucrative drug for treating a rare kidney disease.

The drug, Thiola, is one of the two FDA-approved treatments for an inherited condition that leads to the formation of stones in the kidney, ureter and bladder.

Retrophin acquired the U.S. marketing rights to the drug from privately held Mission Pharmacal Co for an undisclosed sum on Thursday.

The company said it planned to raise the price of Thiola, increase the number of available doses and eventually develop an extended release version.

Thiola, currently sold for $4,000 a year per patient, will be priced closer to rival drug penicillamine, which costs $80,000 to $140,000, Chief Executive Martin Shkreli said on a conference call on Friday.

Such a sudden jump in price could attract regulatory scrutiny especially given recent insurer concern over the rising cost of medicines.

Thiola is the preferred therapy for cystinuria as it poses a lower risk of toxicity, Shkreli said.

While penicillamine is also used in the treatment of Wilson's disease and rheumatoid arthritis, Thiola is only approved for use in cystinuria.

Thiola is currently available in a 100 mg dose, which Retrophin plans to discontinue. The company intends to launch 250 mg and 500 mg doses.

Retrophin raised its full-year revenue forecast on Thursday to $30 million-$35 million from $20 million-$22 million.

"I believe the guidance is conservative, and I look forward to updating it," Shkreli said.

The company also lifted its 2015 revenue forecast to $60 million-$70 million from $36 million-$41 million.

Thiola was approved in 1988 by the U.S. Food and Drug Administration for the treatment of cystinuria, which affects about 1 in 10,000 people, according to the National Institutes of Health.

Retrophin, which has hypertension drug Vecamyl and metabolism treatment Chenodal in the U.S. market, is developing a number of drugs for rare diseases including rage disorders, Duchenne muscular dystrophy and infantile spasms.

The New York-based company's shares were up 16 percent at $15.00. The stock was one of the top percentage gainers on the Nasdaq. (Reporting by Natalie Grover in Bangalore; Editing by Kirti Pandey)