Inspire (Nasdaq: ISPH) is the subject of a “formal, nonpublic investigation” by the US Securities and Exchange Commission, the company said in a statement issued Wednesday morning before the markets opened.

“The Company believes relates to trading in the Company’s securities surrounding its February 9, 2005 announcement of the results of its Phase 3 clinical trial of diquafosol tetrasodium for treatment of dry eye (Study 109), as well as the Company’s disclosures regarding this Phase 3 clinical trial,” Inspire said in a statement. “The Company and one of its directors have each received a subpoena in connection with this investigation.”

The director was not identified.

The company’s stock price was not affected by the news. Its price actually climbed 6 cents to close at $9.64.

On Feb. 9, Inspire disclosed that the diquafosol “failed to demonstrate statistically significant improvement as compared to placebo for the primary endpoint of the incidence of corneal clearing.”

Inspire stock had been trading at more than $15 a share before the announcement. It immediately lost some $6. Inspire’s 52-week high is $19.19. Its 52-week low is $6.24.