We demonstrated in a phase 1 trial that an immunotherapy (AGS-004) consisting of a monocyte-derived dendritic cells (DC) and RNA encoding autologous HIV antigens (Gag, Nef, Rev, Vpr) derived from the patient's own pre-ART plasma induced immunogenicity in most patients. Based on these results a multicenter phase 2 trial was implemented to assess the safety and proportion of patients demonstrating viral load (VL) < 1000, < 5000 and < 10,000 copies/ml during the 12 week ART structured treatment interruption (STI).

Subjects on their initial ART regimen with VL < 50 copies/ml, CD4 > 450 cells/μl, CD4 nadir > 200 cells/μl and a pre-ART VL > 10,000 to 500,000 copies/ml were eligible. The treatment consists of 4 intradermal AGS-004 doses administered monthly in combination with ART followed by two more doses during the 12 week STI. Subjects who participated in the phase 1 study were included and received a second cycle of AGS-004. Subjects may continue AGS-004 booster administration if VL remains < 10,000 copies/ml.

33 subjects were enrolled from 11 Canadian sites, and AGS-004 successfully manufactured and administered to 21 subjects. 9 subjects have successfully completed 12 weeks of STI. The immunotherapy related AEs were Grade 1 or 2 flu-like, GI symptoms, fatigue, and injection site reactions. During the STI, no reports of autoimmunity or AIDS defining events were observed. After an initial viral rebound, 4 out of 9 subjects had > 2 instances of VL measures < 1000 copies/mL when assessed every 2 weeks during the STI. At week 12 of STI 5 subjects had viral loads < 10,000 copies/ml with CD4 > 350 cells/μl including 4 subjects with viral loads < 5000 copies/ml.

Results from this phase 2 autologous immunotherapy trial demonstrated that this therapy is safe and induced partial control of VL when compared to pre-ART VL during the 12-week STI.