Washington Editor

Inspire Pharmaceuticals Inc.’s stock gained back a little ground when the company started enrollment of a third Phase III trial of INS365 Ophthalmic for dry eye.

Inspire’s stock (NASDAQ:ISPH) closed Wednesday at $2.25, up 13 cents on a rough day for biotech stocks.

The need for a third Phase III became apparent in January when Inspire, of Durham, N.C., released poor preliminary data from its first Phase III, known as Study 104. Another Phase III, called Study 105, is ongoing and results are expected this summer. (See BioWorld Today, Jan. 17, 2002.)

Negative news surrounding Study 104 sent the company’s stock tumbling 73 percent, or $11.36, to close at $4.15.

But now, the company said results from this third trial likely would be used to support a new drug application for INS365 Ophthalmic.

The product is an eye drop designed to activate the P2Y receptor, a specific receptor on the surface of the eye believed to be a physiological regulator of a number of processes in the eye, including natural cleansing and protective mechanisms as well as hydration on the surface. Dry eye is a painful, burning and irritating condition involving abnormalities and deficiencies in the tear film due to a variety of causes, the company said.

Unlike the previous Phase III trials, Study 108 will be conducted in a “controlled adverse environment.”

“This is essentially a chamber where we can control things like humidity,” Mary Bennett, Inspire’s vice president for operations and communications, told BioWorld Today. “For example, if it is very humid, people who don’t have severe dry eye may not have as big a problem, so individuals who are running this trial are very experienced in using these controlled adverse environments and they believe that the use of these environments will help to minimize the placebo effect.”

A strong placebo effect caused Study 104 to fail, Bennett said. And even though 104 and 105 are identical (both enrolled 500 patients), the company believes 105 will be successful.

“We potentially have a better chance of positive results with 105 because now that we have done a full analysis of 104, we see where we did have some positive signs or signals, and we can go back to the FDA and ask to analyze 105 differently,” Bennett said. “In 104 we saw a good drug effect; it was comparable to what we saw in Phase II. The reason we didn’t show a significant difference between the drug and placebo was not because the drug didn’t work as well, but because the placebo effect was very large.”

In Phase II trials, INS365 Ophthalmic was shown to be very well tolerated and demonstrated a statistically significant improvement over placebo on the efficacy endpoint, the company said.

Meanwhile, Study 108 is a placebo-controlled, double-masked comparison of the safety and efficacy of 2 percent INS365 Ophthalmic eye drops to placebo in 200 patients.

Bennett said publishable results from 108 are expected in the first half of 2003.

Completion of Study 104 and submission of its data triggered a milestone payment for Inspire from its partner, Allergan Inc., of Irvine, Calif. The companies entered a deal valued at upwards of $39 million to develop INS365 Ophthalmic and Allergan’s dry-eye product, Restastis. (See BioWorld Today, June 28, 2001.)

While Inspire recently successfully completed a Phase I trial of INS37217 Intranasal for upper respiratory disorders, in order to cut back on operating expenses, the company temporarily stopped studies on products for chronic bronchitis and atrophic vaginitis.