Thalidomide drug may fight blood vessel disorder

* Potential new use of drug adds to its revival

* Study found treatment reduced severity of nosebleeds

LONDON, April 4 (Reuters) - Thalidomide, a drug that caused birth defects when it was launched as a morning sickness pill half a century ago, may be useful for treating a hereditary condition that affects blood vessels, scientists said on Sunday.

In a study in the journal Nature Medicine, French researchers found giving thalidomide to patients with a disorder called hereditary hemorrhagic telangiectasia (HHT) reduced the severity and frequency of nosebleeds, one of the main symptoms.

Franck Lebrin, who led the study with colleagues from the National Institute for Health and Medical Research (INSERM) in Paris, said experiments on mice with HHT showed thalidomide treatment was able to repair blood vessel wall defects through a mechanism involving proteins involved in cell growth.

"Biopsies of the nasal surface tissue from patients with HHT showed that similar mechanisms may explain the effects of thalidomide treatment in humans," he wrote in the study.

HHT affects about one in 5,000 people. Many patients develop recurrent, difficult-to-treat nosebleeds which can significantly harm their quality of life.

Thalidomide was used to treat nausea during pregnancy in the 1960s. The drug was taken off the market after severe congenital defects appeared in the newborns of mothers who had taken it.

More recently, thalidomide -- which has powerful anti-cancer properties -- experienced a revival and is now being used to treat certain forms of cancer such as multiple myeloma.

U.S. drugmaker Celgene (CELG.O) has developed a successor drug to thalidomide, called Revlimid, which is also approved to treat multiple myeloma. (Reporting by Kate Kelland, editing by Janet Lawrence)