Antibody Responses to Pneumococcal Vaccines Among HIV-infected Adults.

Streptococcus pneumoniae (SP) is the major cause of bacterial infection in HIV-infected patients. The 23-valent pneumococcal polysaccharide (PPV) is poorly immunogenic in patients with CD4 below 500 cells/mm3. The purpose of this multicentric national study is to evaluate whether a prime with a 7-valent pneumococcal conjugate vaccine (PCV), able to induce immunological memory, would improve immunogenicity against SP polysaccharides. 212 HIV-1 infected patients, with a CD4 count between 200 and 500/mm3, will be randomly assigned to one of two vaccine groups: PCV at Week 0 followed by PPV at Week 4 or PPV alone at Week 4. Evaluation will be done at week 8. The primary endpoint is the proportion of patients who had antibody responses against 7 pneumococcal polysaccharides at Week 8. Secondary endpoints include the persistence of antibody responses at Weeks 24 and 96, vaccines safety and occurrence of pneumococcal disease over time.

Inclusion criteria

• Adult patients with proven HIV-1 infection
• Naïve or antiretroviral experienced
• CD4 cell count between 200 and 500/mm3
• Plasma HIV RNA load lower than 4 log10 copies/mL
• Signed written informed consent

Exclusion criteria

• Immunotherapy
• Immunization with the PPV within the past 5 years
• Splenectomy
• Use of intravenous immunoglobulin within the past 2 months
• Chemotherapy or radiation
• Any other vaccination within the past 2 months
• Severe renal failure
• End-stage liver disease
• Pregnancy