US FDA approves GSK's drug for liver disease-related itching

March 19 (Reuters) - The U.S. Food and Drug Administration approved GSK's GSK.L drug for severe itching caused by a type of liver disease, the company said on Thursday.

The drug, branded Lynavoy, was approved for patients with primary biliary cholangitis, or PBC. Existing therapies do not directly address severe itch or cholestatic pruritus.

"The approval of Lynavoy in the US gives patients a much needed treatment option that offers rapid, significant and sustained improvement in the debilitating effects of itch caused by PBC," said GSK executive Kaivan Khavandi.

Earlier this month, GSK said Alfasigma will acquire worldwide exclusive rights to develop, manufacture and commercialize the pill.

The companies did not immediately respond to Reuters' requests for comment on pricing and availability details.

PBC is a chronic disease where the body's immune system mistakenly attacks and destroys the small bile ducts in the liver. It affects more than 100,000 adults in the United States, according to National Institues of Health data.

The drug works by blocking a protein in the intestine that normally reabsorbs bile acids that cause severe itches.

In a late-stage trial, the twice-daily oral pill showed a statistically significant reduction in itch severity and itch related sleep disruption in PBC patients when compared with placebo over 24 weeks.

Currently, PBC-related pruritus are treated with off-label drugs. Gilead's Livdelzi and Ipsen's Iqirvo are given for PBC itself but does not directly target the symptom.

Mirum Pharmaceuticals MIRM.O is also developing its drug, volixibat, for pruritus in PBC.