• To demonstrate the safety and tolerability of the PepTcell HIV vaccine by analysis of safety data including changes in HIV load and CD4 T cell count. [ Time Frame: Pre-vaccination, days 1, 2, 7, 14, 21 and 28 after vaccination and weeks 8, 12, 16, 20 and 24 after vaccination ] [ Designated as safety issue: No ]
  

The study will consist of a screening period of 3 to 21 days before vaccination on Day 0 and a double-blind treatment period of 28 days with a follow up period of 5 months. Prior to conducting any study-related procedures, subjects will provide written informed consent. During screening, eligibility will be assessed, a medical history will be taken, a complete physical examination will be performed and vital signs will be measured. Blood samples will be taken for the assessment of HCV and HBV status. Further samples will be taken for CD4 and HIV load, haematology, biochemistry, urinalysis and a 12-lead electrocardiographic (ECG) assessment will be carried out. A self-assessment diary card will be used by subjects between Day 0 and Day 28 to record any AEs.

On Days 7, 14, 21 and 28 an AE interview will be conducted, concomitant medications and vital signs will be recorded and a physical examination will be performed. Samples will be collected for haematology, clinical chemistry and urinalysis. In addition, samples will be collected for CD4 T cell count and HIV viral load at days 14 and 28 after vaccination. A sample will be collected for immunogenicity on Day 28.

All patients will attend follow-up visits at Weeks 8, 12, 16, 20 and 24 at which a physical examination and examination of the injection site will be performed and vital signs measured. Samples will be collected for haematology, biochemistry, urinalysis CD4 T-cell count and HIV viral load. Blood samples for immunogenicity testing will be collected at Weeks 12 and 24.

Stage I: Sequential, non-randomised, single blind, parallel group. Five male HIV-1 positive volunteers will be vaccinated in a sequential, non-randomised single blind fashion. They will each receive one of the five possible active study treatments (WFI only, adjuvant only, low dose + WFI, low dose + adjuvant, high dose + WFI and high dose + adjuvant). Each of these five patients will be observed as in-patients for 24 hours after vaccination and vaccinations will be performed in a sequential manner with at least 48 hours observation of each patient before vaccination of the next patient is commenced.

Following completion of the '28 day treatment follow up' by the five Stage I subjects a Safety Committee will review the safety and tolerability data for these subjects and will make a recommendation for continuing or discontinuing recruitment and any changes that may be required in the conduct of the study. Subject to a positive decision from the Safety Committee the remaining subjects will be recruited into Stage II of the study.

Stage II: randomised, double-blind group 50 male HIV-1 positive volunteers will be randomised to one of five possible treatment groups. Following completion of the Day 1 Visit by the first five subjects in Stage II the Safety Committee will review the blinded safety and tolerability data for these subjects. Subject to acceptable safety and tolerability, the centres will be allowed to continue recruitment for the rest of the planned cohort.

After 25 Stage II subjects have completed the Day 1 Visit a Safety Committee will review the blinded data generated and will make a recommendation for continuing or discontinuing recruitment and any changes that may be required in the conduct of the study.