Semi-automatic COVID-19 vaccine preparation for upscaling of vaccination: a descriptive study

Abstract Objectives Vaccines are used on a large scale for prevention of disease. Preparing vaccines for administration can be a time consuming process. To increase efficacy of vaccine administration, the Vaxtractor was designed in January 2021. With the Vaxtractor, the desired volume of vaccine is drawn up automatically in syringes from two vials of vaccine simultaneously. We examined the quality of COVID-19 vaccines prepared with the Vaxtractor. Methods Sterility tests and uniformity of dosage units tests were performed. For the sterility test, 22 syringes were filled with 0.5 mL Tryptic Soy Broth and these were incubated at 25 °C for seven days followed by seven days at 30 °C. For the dosage unit test, the difference between the filled and empty syringe was used to compute the volume of the injectable volume. A time analysis was performed on manually and semi-automatically prepared vaccines. Results The sterility tests showed no signs of growth of micro-organisms. After optimizing the Vaxtractor, none of the Comirnaty® vaccines deviated more than 10 % and none of the Spikevax® vaccines deviated more than 5 % compared to the mean mass of the injectable volume. The acceptance value for uniformity of dosage units of both vaccines was below 4 (requirement <15). Preparing vaccines with the Vaxtractor was faster compared to manually prepared vaccines. Conclusions The Vaxtractor can be used to safely prepare Spikevax® and Comirnaty® vaccines. Further studies should explore the applicability of the Vaxtractor for the preparation of other vaccines. If applicable, this will contribute to effective upscaling of vaccination programs.