Methods Based on in-vitro neutralizing activity in serum, patients (n=6, subtype A and B infected) were selected and Env sequences of early HIV-1 variants, still sensitive to autologous neutralization, were used to generate soluble Env as immunogens. Gp140 trimeric proteins were expressed (293T cells) and purified. Rabbits (4/group) were immunized s.c. at weeks 0, 2, 4, 8 with 100μg trimer adjuvanted with cationic CAF01. Control groups received 20μg and 100μg trimer plus/minus CAF01 respectively. Sera collected at weeks 0, 2, 4, 8, 12 and 14 were screened in gp120-IIIB ELISA and IgG was analyzed in the TZMbl neutralization assay.