Special Investigation of Pfizer's COVID-19 Vaccine in Participants Aged 12 Years and Older with Comorbidities Considered to Have a High Risk of Aggravating COVID-19

<p>A special survey on drug use outcomes was conducted to assess the clinical safety of Comirnaty intramuscular injection (Monovalent: Original) during the period between the time of administration of the first dose and 28 days after administration of the second dose among recipients with comorbidities considered to increase the risk of developing severe COVID-19.</p><p>A total of 1,075 participants were recruited from 17 sites between May and August 2021. The safety analysis cohort included 1,038 participants, which included 58.29% males and 41.71% females. The median age of the participants was 63.0 years.</p><p>The overall incidence of adverse reactions (ARs) was 5.68%. Among males and females, the incidences were 3.80% and 8.31%, respectively. The incidences were 7.57% and 3.21% among participants in the 15-64 years and ≥65 years age groups, respectively. After administration of the first and second doses, 2.89% and 3.78% of participants, respectively, reported ARs. Therefore, the incidences of ARs among participants who were females, young, and second dose recipients were higher than those among males, elderly, and first dose recipients, respectively. The incidences of Grade 1 or higher local reactions and systemic reactions according to the medical records of participants were 80.77% and 62.61% for the first dose and 84.41% and 69.79% for the second dose, respectively.</p><p>A risk ratio adjusted for sex and age was confirmed from further subgroup analyses, and no baseline characteristics were found to affect the incidence of ARs.</p><p>These findings were similar to those obtained from clinical trials conducted in and outside Japan and those obtained from the Japanese-focused survey in the early stages of administration of the new COVID-19 vaccine. No new concerns regarding the safety of Comirnaty were found. (ClinicalTrials.gov ID: NCT04880447)</p>