Phase 3 trial halted for proposed Alzheimer's treatment

Baxter International Inc. announced Tuesday that its phase 3 clinical trial of intravenous immunoglobulin failed to reduce cognitive decline and preserve functional abilities in patients with mild to moderate Alzheimer’s disease.

The Gammaglobulin Alzheimer’s Partnership (GAP) clinical trial treated 390 patients with mild to moderate Alzheimer’s disease across 45 locations in the United States and Canada. They were randomly assigned to either 400 mg/kg or 200 mg/kg intravenous immunoglobulin (IVIG) treatment every 2 weeks for 18 months.

“… A detailed analysis of the results from the GAP study continues, and we look forward to a greater understanding of the full data set,” Ludwig Hantson, PhD, president of Baxter’s BioScience business, said in a press release.

Based on these results, Baxter will “reconsider its current approach for its Alzheimer’s program.”

According to the press release, patients in the randomized, double blind, placebo-controlled trial did not demonstrate statistically significant difference in the rate of cognitive decline compared with placebo (mean 7.4 in the 400-mg/kg group; 8.9 in the 200-mg/kg group; and 8.4 in the placebo group). In addition, results indicated no significant change in functional ability compared with placebo (mean –11.4 in the 400-mg/kg group; –12.4 in the 200-mg/kg group; and –11.4 in the placebo group).

“Unfortunately, observations of [immunoglobulin] seen in earlier phases of Alzheimer’s patients did not translate into a positive outcome in the GAP study,” said Norman Relkin, MD, PhD, a neurologist from the Weill Cornell Medical College.