Intradermal COVID-19 vaccination studies are emerging in a global effort to multiply available doses by harnessing skin immunity to reduce dosage required for effective vaccination.

In a hallmark study published recently by scientists at the Institute of Medical Biology (IMB) in China, subjects were immunized twice with IMB's inactivated SARS-CoV-2 vaccine intramuscularly. About six months later, 20 participants randomly received 1/15 (<7%) of the vaccine dose intradermally (into the skin) using NanoPass's MicronJet™600 device.

Significant increases in antibody levels were demonstrated one week and 2 months after the injection (X8-10 and X12.5-97 than baseline, respectively). Six months later, antibody levels were reduced but remained significantly higher than baseline (X8.5-12).

These results have shown that the intradermal 3rd boost allowed for robust and sustained (>6mo) immunogenicity with a favorable safety (no fever and only mild injection site redness and swelling).