Amylin Pharmaceuticals Inc. saw its shares rise 27.7 percent following the release of positive early data from an ongoing Phase II study of its long-acting release (LAR) formulation of Byetta in Type II diabetes patients.

Those results "are what we hoped for," said Dan Bradbury, chief operating officer of San Diego-based Amylin, which is developing the LAR version with partners Eli Lilly and Co., of Indianapolis, and Alkermes Inc., of Cambridge, Mass. "We've completed the active dosing portion of the study, and we felt that the results were of such importance that we should make them available as quickly as possible."

Shares of Amylin (NASDAQ:AMLN) gained $6.07 Tuesday to close at $28.

The randomized, placebo-controlled study involved 45 Type II diabetes patients who were not able to manage their glucose levels through diet and exercise, with or without the help of metformin. After 15 weeks of treatment, both doses of the once-weekly injection of Byetta were found to be well tolerated, and the higher dose of the LAR formulation demonstrated a 2 percent improvement in glucose control as measured by hemoglobin A1C.

Patients will continue to be evaluated during a 12-week follow-up period. The trial is expected to conclude around the end of the fourth quarter, Bradbury said, adding that the company has not yet provided a timeline for regulatory filing.

"The important next step will be to have discussions with the FDA as to what [the agency's] requirements will be for the approval of this long-acting version," he told BioWorld Today.

At the start of the trial, the average A1C of participants was 8.5 percent. Within the treatment period, 12 of the 14 high-dose subjects achieved an A1C level of 7 percent or less, which is the glucose threshold recommended by the American Diabetes Association. None of the 14 patients receiving placebo achieved that target. Patients receiving Byetta also reported an average weight loss of nine pounds, compared to placebo.

"The glucose control improvement was significantly greater than we have seen in the Byetta program to date," Bradbury said. "We always thought that having a less frequent dosing regimen would be more convenient to patients, but these preliminary results suggest that the product may also have a better overall profile."

About 18 million people in the U.S. have Type II diabetes. Of those, roughly 3 million to 3.5 million use insulin to control their blood sugar levels. The remaining population relies on medication or on diet and exercise, but in many cases, that might not be enough to maintain healthy glucose levels. That's where Byetta comes in.

Byetta (exenatide), in a class of drugs known as incretin mimetics, is designed to stimulate the body's ability to produce insulin to combat elevated blood sugar levels.

A twice-daily injection of Byetta was approved in April as an adjunct treatment for Type II diabetes patients who failed to achieve adequate blood sugar control using metformin or sulfonylurea, or a combination of the two. That approval followed three successful Phase III studies involving nearly 1,500 patients that showed statistically significant reductions in glucose levels. Amylin and development and co-promotion partner Lilly launched Byetta in June, and Amylin recorded sales revenue of $7.5 million through June 30. (See BioWorld Today, May 2, 2005.)

The companies also received an approvable letter for a monotherapy indication of Byetta, though, at this time, no additional data have been submitted.

Alkermes joined the collaboration to develop the long-acting Byetta formulation. Under the agreement, it contributes its Medisorb injectable long-acting-release delivery technology.

Shares of Alkermes also received a boost following the release of the Phase II data. Its stock (NASDAQ:ALKS) closed at $17.67 Tuesday, up $1.84, or 11.6 percent.

While it partners its delivery technology, Alkermes also develops its own product pipeline. The company is awaiting FDA approval for Vivitrex, its once-monthly injection to treat alcohol dependence. The review deadline is Sept. 30.

Beyond Byetta and a second approved diabetes drug, Symlin (pramlintide acetate) for Type I and II diabetes patients whose insulin is not working, Amylin has four other products in its development pipeline: an obesity drug and a product for congestive heart failure, both in Phase II, and a second obesity drug and a product for atherosclerosis related to cardiovascular disease, both in Phase I.