Backgrounds:

There is a need to assess the immunogenicity and duration of immune response to SARS-CoV-2 mRNA vaccination in HIV-infected patients. Scarce data exist on HIV-infected adolescents.

Methods

A prospective ongoing observational study is being conducted in HIV-infected patients > 12 years of age after the introduction of mRNA vaccination in Spain. Blood samples were drawn 3-10weeks after the first or second dose (according to prior SARS-CoV2 infection) of BNT162b2 (Pfizer/BioNTech) and CoV-2-mRNA-1273 (Moderna) vaccines in 20 HIV-infected adolescents and compared to 20 matched healthy-control subjets. Humoral response was assesed by detection of SARS-CoV-2 antibodies by chemiluminescent-microparticle-immunoassay (CMIA) (Alinity® Quant assay-Abbott) to detect IgG against S1-region of the spike-protein of SARS-CoV-2 (≥50U/mL considered reactive). T-Cell response to SARS-CoV-2 was measured by an interferon-gamma-released-assay (IGRA,Euroimmun) of S1 peptide-stimulated T-cells in whole blood (≥200mlU/ml considered reactive).

Results:

Blood samples from 20 HIV-infected adolescents were drawn after vaccination (15 Pfizer/BioNTech, 5 Moderna), see figure one. Mean age was 16.7±3.9 and 14.3±3.9 years in patients and controls, respectively (p:0.06). Mean intervals since last vaccine dose in HIV-infected and controls were 44.0±15.1 and 38.5±12.6 days,(p>0.05). Two HIV-infected patients and 6 controls had documented past SARS-CoV-2 infection.

All patients and controls had reactive humoral and celular responses. HIV-infected subjects had lower anti-Spike antibodies titers (mean 14251±8270 U/mL) than controls (mean 27716±15768 U/mL)(p:0.013). Likewise, cellular immune responses were lower in HIV-infected adolescents (mean 1609±418 mlU/ml) than in controls (mean 1777±356 mlU/ml),(p:0.024).

Conclusions/Learning Points:

Perinatally HIV-infected adolescents with good immunologic and virological status elicit appropriate specific antispike-antibody levels and cellular immune responses against SARS-CoV-2 shortly after mRNA vaccination, but of lower amount than healthy control subjects. More prolonged studies are underway to determine the evolution of humoral and cellular immune responses after vaccination.