Drug news: Japan approves Prolacria sibling from Inspire

Japan approves dry-eye drug from Inspire, Santen

A stronger version of a dry eye drug stymied by regulatory roadblocks in the United States has won approval for sale in Japan, Durham-based Inspire Pharmaceuticals announced Friday.

Inspire (Nasdaq: ISPH) and its partner on the drug, Japan-based Santen Pharmaceutical Co., Ltd., said in a joint news release that the Japanese Ministry of Health, Labour and Welfare gave the companies the green light Thursday to begin sales of Diquas Ophthalmic Solution 3%.

Diquas has the same active ingredient, diquafosol tetrasodium, as the Inspire drug Prolacria, which twice has failed to perform better than placebo in phase III clinical trials in the United States.

Clinical studies in Japan found that Diquas eased dry-eye symptoms by promoting the secretion of mucin and water. The drug also was found to be well tolerated in patients.

The drug that passed muster in Japan is different from Prolacria in two major ways, said Inspire spokeswoman Cara Amoroso. No. 1, Prolacria was a 2 percent diquafosol solution; Diquas is 3 percent. No. 2: Patients in the last Prolacria trial received four doses a day; patients in the Japanese tests used the eye drops six times a day.

Inspire is unlikely to pursue Food and Drug Administration approval of Diquas, with its higher concentration and dosaging, Amoroso said.