Prolacria (diquafosol tetrasodium ophthalmic solution) 2% has entered a Phase III trial for the treatment of dry eye disease, according to an announcement from the solution's developer, Inspire Pharmaceuticals, Inc. The design of the trial was agreed between Inspire and the FDA under a Special Protocol Assessment (SPA).

The randomized, placebo-controlled, multicentre environmental trial, which will assess safety and efficacy, has now begun enrolling the first of a planned 450 study subjects. Subjects will receive either Prolacria, a P2Y2 receptor agonist, or placebo eye drops four times daily for six weeks. A criterion for inclusion in the trial is a fluorescein staining score of three in the central cornea, and the primary efficacy endpoint is a score of zero at six weeks.

In 2005, the FDA had requested further information on Prolacria, following a statement regarding a possible recommendation by the US Securities and Exchange Commission (SEC) that a lawsuit — relating to possible fraudulent violations involving the use of manipulative and deceptive devices in late stage trial data — be brought against Inspire CEO Christy L. Shaffer and Mary B. Bennett, Inspire's executive vice president of operations and communications. Therefore, under the current SPA, any positive results in terms of efficacy in this trial will be considered in conjunction with previous Prolacria trial results, and the overall risk/benefit ratio.