By Jessica Toonkel
NEW YORK (Reuters) - ViroPharma Inc, a drug maker specializing in rare diseases, is attracting preliminary acquisition interest from several pharmaceutical companies, according to three people familiar with the matter.
No deal is imminent for the "orphan" drugmaker, which has a market capitalization of $1.8 billion, said two of the sources, who requested anonymity because they are not permitted to speak to the media.
While ViroPharma is not pursuing a sale, potential buyers are looking at the 19-year-old company because of its pipeline of drugs for rare diseases, the sources said.
A ViroPharma spokeswoman declined to comment.
ViroPharma makes drugs designed to treat unusual diseases that affect small patient populations. For example, one of its drugs, Cinryze, aims to prevent bodily swelling or painful attacks in teenagers and adults with Hereditary Angioedema, a genetic immune disorder.
Pharmaceutical companies are increasingly interested in developing or buying orphan drugs, as their more conventional products have lost market share to generic competitors.
The trend began, in 2011 French drugmaker Sanofi SA bought Genzyme Corp, the first company to show that it could make money from treatments for rare diseases, for $20.1 billion, one of the sources said.
ViroPharma is one of a handful of orphan drug makers that pharmaceutical companies see as potential acquisition targets, said the people familiar with the matter.
Another orphan drug maker, BioMarin Pharmaceuticals, has also been viewed as an attractive target. Its shares have surged almost 60 percent over the past 12 months to a market value of more than $8 billion, making it too expensive for most potential buyers, sources said.
BioMarin is "not actively looking to be acquired," and is focused on long-term growth, a company spokeswoman said.
ViroPharma would not be a cheap acquisition either. The company's stock is up more than 20 percent over the past 12 months, trading around $27.00 per share. It was not clear what price ViroPharma would want.
Last week, ViroPharma said its maribavir drug, which is designed to treat patients who develop a type of herpes virus and also have a condition called impaired cell mediated immunity, received orphan drug designation in Europe.
With the orphan drug designation, ViroPharma has gained 10 years of potential market exclusivity if the product is approved for marketing in the European Union and the orphan designation is maintained. The drug already has orphan designation status in the United States.
ViroPharma's shares were up almost 9 percent in early afternoon trading, at around $29.50 per share.
(Reporting by Jessica Toonkel; Additional reporting by Soyoung Kim; Editing by Lisa Von Ahn)