GSK seeks to expand low-platelet drug Promacta to hepatitis C patients...

Posted on 5/30/12 via MedCityNews.com. GSK seeking to expand drug level to include thrombocytopenia, both pre initiation of therapy for patients with low baseline platelets and  thrombocytopenia as a result of HCV therapy. 

GlaxoSmithKline (NYSE:GSK) wants now wants approval to use its low platelet drug Promacta to treat hepatitis C patients.

GSK has filed regulatory applications in Europe and the United States to add the new indication to the drug. The drug eltrombopag, which is marketed under the brand name Promacta in the United States and Revolade globally, is approved in 88 countires to treat immune thrombocytopenia, a condition in which a patients has low blood counts because the platelets are destroyed by the patient’s own immune system. The condition puts patients at the risk of bleeding. Promacta was co-discovered by GSK predecessor SmithKline Beecham and partner Ligand Pharmaceuticals.

The British pharmaceutical giant, which has its U.S. headquarters in Research Triangle Park, North Carolina, is now seeking to expand approval of the drug to increase platelet counts in patients who have chronic hepatitis C virus infection. The drug would allow them to start interferon-based therapy and could also be used to optimize interferon-based therapy, according to to GSK’s supplemental new drug application.

GSK last year completed a phase 3 study of Promacta in hepatitis C patients whose low platelet levels make them unable to start interferon therapy to treat the virus. The trial met the primary endpoint of improving the sustained virological response.

Promacta does come with some safety risks. Until late last year, the U.S. Food and Drug Administration required doctors and patients to follow a strict regimen in order to watch for adverse effects including liver damage, blood clots and bleeding risks after discontinuing the drug. But the FDA eased those requirements concluding that it was unlikely the safety data collected could determine whether adverse effects were caused by the drug or by the immune thrombocytopenia. While mandatory collection of safety data is no longer required, the agency continues to ask that any adverse events be reported.

UBS analysts see bright future in GSK's Promacta for HCV treatment-associated thrombocytopenia...

Article from Bloomberg.com. UBS analysts see potential 'blockbuster' status from GSK's Eltrombopag in the treatment of HCV treatment-associated thrombocytopenia.

Glaxo’s Promacta May Turn Into Blockbuster Medicine, UBS Says

By Makiko Kitamura

Nov. 7 (Bloomberg) -- GlaxoSmithKline Plc’s Promacta blood disorder medicine may generate as much as $2 billion in annual sales if the U.K.’s largest drugmaker can expand its use to the treatment of a condition associated with hepatitis C, according to UBS AG.

The medicine, already approved for sale in the U.S. to raise platelet counts in patients with a rare blood disorder, is being studied to extend use to patients with thrombocytopenia, a blood complication stemming from hepatitis C treatments. Glaxo will present results from the last of three stages of clinical testing required for regulatory approval on the new use at a medical meeting in San Francisco today.

As many as 170 million people worldwide are chronically infected with the hepatitis C virus, which can lead to cirrhosis of the liver and liver cancer, according to the World Health Organization. Glaxo’s Promacta would enable hepatitis C patients to be treated with antiviral medicines for longer periods of time, turning the drug into a “potential blockbuster,” said Gbola Amusa, a health-care analyst at UBS in London.

“Depending on how positive the data are, this could generate an additional $2 billion in annual sales,” Amusa said. Promacta had sales of 51 million pounds ($82 million) through the end of September, compared with 31 million pounds in 2010.

The study results are slated to be presented at the American Association for the Study of Liver Diseases’ annual Liver Meeting at 3:15 p.m. San Francisco time.

Sales Estimate

If the data are positive, an approval by regulators may come as early as the end of next year, Amusa said. The sales estimate assumes that antiviral medicines including interferon will continue to dominate hepatitis C treatments, Amusa said. Abbott Laboratories last month presented interim study results for a new alternative therapy that does not use interferon.

“Undoubtedly, this would be a big potential opportunity for the drug if it demonstrates strong results,” said Gustav Ando, a health-care analyst at consulting company IHS Global Insight in London. “We remain somewhat cautious until we see some of the side-effects data.”

Any potential damage to the liver in terms of toxicity along with blood clotting are of concern, Amusa and Ando said.

Glaxo said on Oct. 26 it plans to file as many as 10 drugs for approval next year. The compounds in late-stage development include Relovair, which Glaxo is developing as a successor to the Advair asthma inhaler. Advair, Glaxo’s best-selling product, generated 19 percent of total revenue in the first half of the year.

Three Glaxo products have been cleared for sale this year, including Benlysta, a therapy for the auto-immune disease lupus that was approved by U.S. regulators in March. The company’s global sales in the quarter ended Sept. 30 rose 4.3 percent to 7.1 billion pounds from a year earlier.

--Editors: Bruce Rule, Kristen Hallam

To contact the reporter responsible for this story: Makiko Kitamura in London at mkitamura1@bloomberg.net

To contact the editor responsible for this story: Phil Serafino at pserafino@bloomberg.net