Dry eye drug from Inspire gets patent extension in Japan

Two dry eye therapy patents owned by Inspire Pharmaceuticals (NASDAQ:ISPH) have received extensions in Japan, which gives the drug Diquas patent protection until February 2023.

Raleigh, North Carolina-based Inspire disclosed in a securities filing that the extension gives one Diquas patent an additional five years of exclusivity; another patent received approximately 4.5 years of exclusivity. The patents cover the drug, its formulation and the method of making the product.

Diquafosol tetrasodium, marketed as Diquas, was launched in December by Japan-based drug partner Santen Pharmaceutical Co. Inspire and Santen entered into an agreement in 1998 that gave Santen an exclusive license to develop and market Diquas in Japan and nine other Asian countries. Inspire is entitled to receive royalties on Diquas sales in Japan based on a tiered rate of net sales.

Inspire dry eye treatment Restasis is sold in the United States through partner Allergan (NYSE:AGN). The company also has products for treating bacterial conjunctivitis as well as eye itchiness associated with allergies. Inspire has refocused its business on eye care products following the failure of cystic fibrosis drug candidate denufosol in late-stage clinical trials. The company had planned to diversify by developing pulmonary therapeutics. But shortly after denufosol’s failed clinical trial, the company instead announced a restructuring that would get the company out of pulmonary therapeutics. The company’s $106.3 million in 2010 revenue came entirely from the company’s eye business.