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Potential ViroPharma drug receives orphan status

EXTON, Pa. (AP) -- European regulators have granted orphan drug status to a potential ViroPharma Inc. treatment for a virus that can lead to serious disease or death in people with compromised immune systems.

The Exton, Pa., company said Tuesday that the European Commission's designation for maribavir could provide 10 years of market exclusivity if the drug is approved. The designation also may lead to a European Union-funded research grant, reduced regulatory fees and help with clinical development.

Maribavir aims to treat cytomegaloviral disease, which is a member of the herpes virus group that also includes cold sores and chicken pox. It can remain dormant in the body for long periods of time and causes little to no apparent illness in healthy adults. However, it can cause problems for children born with a cytomegaloviral infection as well as for cancer, HIV or transplant patients.

ViroPharma said current treatments are effective, but toxicities limit their use. It has maribavir in mid-stage testing. The potential treatment also has received an orphan-drug designation in the United States.

Shares of Viropharma climbed 32 cents to $28.11 in morning trading Tuesday. Its shares have traded in a 52-week range of $19.58 to $31.36.