Background

Affitope AD02 is a synthetic peptide of six amino acids that mimics the N-terminus of Aβ. AFFiRiS hypothesizes that this fragment enables exclusive recognition of Aβ without cross-reacting with APP, and hence may have a favorable safety profile. This immunogen is short and non-self. Lacking the most common T cell epitope (within amino acids 15–42 of Aβ) but including the B cell epitope (within the first 11–15 amino acids of Aβ), it may allow for the production of anti-Aβ antibodies while minimizing a pro-inflammatory TH1 response.

Findings

A Phase 1 study conducted in Austria tested subcutaneous AD02 alone and with aluminium hydroxide adjuvant in 24 patients with mild to moderate Alzheimer's disease. It showed a favorable safety and tolerability profile at one year. No meningoencephalitis was reported. Phase 1b extensions tested booster doses, immunogenicity, and tolerability at two years.

Between September 2010 and December 2013, a 332-patient, multicenter Phase 2 trial of AD02 in patients with early AD as diagnosed by episodic memory deficit and hippocampal atrophy was conducted in Europe. At a press briefing in June 2014, AFFiRiS showed limited trial data suggesting that AD02 had not reached either primary or secondary outcome measures. A follow-up study is still listed as enrolling. 

Data presented at the press briefing discussed two different placebo groups, in contrast to the one listed on the trial's clinicaltrials.gov entry. At the press briefing, Affiris claimed that one of two different placebo formulations had a greater benefit on the primary outcome than the other placebo formulation or any of the three AD02 treatment groups. AFFiRiS then renamed this placebo formulation AD04 (see Jun 2014 News Story). 

See all AD02 trials listed in clinicaltrials.gov.

Clinical Trial Timeline