IV Ig a Bust in Alzheimer’s
Possibly the last immunotherapy hope in established Alzheimer disease, intravenous gamma globulin (aka IV Ig) failed to slow cognitive decline in a large, closely watched phase 3 trial. According to today’s press release from Baxter, the trial sponsor, IV Ig* did not significantly alter cognitive decline or preserve functional abilities over 18 months, when compared with placebo, in patients with mild-moderate AD (total N = 390). Baxter provides a very handy data table here of the topline results.
Like other commercial investigators of AD, however, Baxter remains interested in assessing outcomes of subgroups. Notably there was a numerically greater difference in cognitive decline between some patients** who received high-dose IV Ig and placebo-treated enrollees. But the phase 3 study was not statistically powered to validate these post-hoc analyses.
Generally IV Ig was well tolerated in the study with no new adverse-event signals. The most common side effects (in at least 5% of subjects) were rash and falls in hemoglobin levels. A total of 12 IV Ig-treated patients and 5 placebo-treated patients reportedly experienced serious adverse events.
According to Baxter, its studies of IV Ig in mild-moderate AD will be discontinued. The full study results will be presented at the AAIC in July.
* At doses of either 200 or 400 mg/kg every 2 weeks.
** Specifically those with moderate disease or ApoE4 carriers.