Inclusion Criteria:

All subjects must satisfy ALL the following criteria at study entry:

• Subjects who the investigator believes can and will comply with the requirements of the protocol.
• Written informed consent obtained from the subject prior to any study procedure.
• A male or female between and including 18-55 years at the time of first vaccination.
• Known to be HIV-1 infected and under the care of an HIV physician for a minimum of 6 months. However, subjects who initially presented with a clinical diagnosis of primary HIV infection need to have been diagnosed and under care for at least 12 months.
• ART-naïve. Individuals must never have received ART after HIV diagnosis, including lamivudine used for chronic hepatitis B infection, with the exception of short-term ART for prevention of mother-to-child transmission (PMTCT) at least 12 months prior to enrolment.
• Commencement of ART is not expected, based on current assessment, within the next 12 months.
• Viral load level of 2,000-80,000 copies/mL at screening.
• CD4 count >= 500 cells per mm3 at screening.

• If the subject is female, she must be of non-childbearing potential, i.e. have a current tubal ligation, hysterectomy, ovariectomy or be post-menopausal. Female subjects of childbearing potential may be enrolled in the study, if the subject:

  • has practiced adequate contraception for 30 days prior to vaccination, and
  • has a negative pregnancy test at screening, and
  • has agreed to continue adequate contraception during the entire study period.

Exclusion Criteria:

The following criteria should be checked at the time of screening and before vaccination. If ANY exclusion criterion applies, the subject must not be included in the study:

• Infection with HIV-2. This includes patients with dual infection with HIV-1/HIV-2.
• Had an Acquired Immune Deficiency Syndrome (AIDS) defining clinical illness.
• Use of any investigational or non-registered product within 4 weeks preceding the first dose of study vaccine/placebo, or planned use of any investigational or non-registered product other than the study vaccine during the study period.
• Drug therapy with immunomodulators or steroids within the 12 weeks preceding the first dose of study vaccine/placebo or planned administration during the study period. Acute use of steroids up to 4 weeks preceding the first dose for treatment of hypersensitivity reactions is not an exclusion criterion. Inhaled and topical steroids are allowed.
• Administration of immunoglobulins and/ or any blood products within the 12 weeks preceding the first dose of study vaccine/placebo or planned administration during the study period.

• Planned administration of a vaccine not foreseen by the study protocol during

  • the period starting 2 weeks before the first dose of study vaccine/placebo and ending at Visit 3 (Week 6) (after blood sampling),
  • the period starting from 2 weeks prior to Visit 5 (Week 28) and ending at Visit 6 (Week 30) (after blood sampling)
  • the period starting from 2 weeks prior to Visit 8 (Week 48) and ending at Visit 8 (Week 48) (after blood sampling), with the exception of non-adjuvanted influenza vaccine.
• Concurrently participating in another clinical study, at any time during the study period, in which the subject has been or will be exposed to an investigational or a non-investigational product.
• Any previous vaccination or immunotherapy against HIV.
• A family history of hereditary immunodeficiency.
• History of allergic disease or reactions likely to be exacerbated by any component of the vaccine.
• Acute or chronic infective hepatitis.
• Acute or chronic, clinically relevant pulmonary, cardiovascular, hepatic or renal functional abnormality, as determined by physical examination and/or medical history at screening.
• Grade 3 or grade 4 laboratory abnormality, as defined by Division od AIDS (DAIDS) grading table, at screening
• Pregnant or lactating female.
• Any condition which, in the opinion of the investigator, could compromise the subject's safety or adherence to the study protocol.
• History of medically confirmed autoimmune disease.
• History of malignancy, other than squamous cell or basal cell skin cancer, unless there has been surgical excision that is considered to have achieved cure.
• Unstable asthma
• Food or wine induced asthma.
• Known sensitivity to sulfites or aspirin.
• Known sensitivity to aminoglycoside antibiotics.
• Contraindication to intramuscular injection