Glaxo's platelet booster shows long-term efficacy

LONDON (Reuters) - GlaxoSmithKline's GSK.L experimental platelet-boosting drug eltrombopag has proved effective at increasing platelet levels during long-term treatment, researchers said on Monday.

Preliminary results from the so-called EXTEND clinical study, involving some 90 patients, showed that of those with a baseline platelet count of less than 30,000, 73 percent achieved a platelet count of 50,000 after an average 5 months’ treatment.

Eltrombopag -- which will be sold under the brand names Promacta and Revolade, if approved -- is designed to treat idiopathic thrombocytopenia purpura, an autoimmune disease which results in low blood platelet counts.

Because platelets contribute to blood clotting, patients with low counts bleed more easily than others, heal more slowly and bruise more often.

Eltrombopag, which is given as a pill, is one of several novel drugs in Glaxo’s pipeline which the group believes have blockbuster potential.

It was discovered as a result of a research collaboration between Glaxo and Ligand Pharmaceuticals Inc LGND.O.

Results from the EXTEND study were presented at the annual meeting of the American Society of Hematology in Atlanta.


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