email article A graded dosing protocol allowed two patients with hypersensitivity reactions to the first dose of Moderna's COVID-19 vaccine to receive their second doses safely, researchers said. The patients -- one with an immediate hypersensitivity reaction managed on site and one needing emergency department transport -- got divided second doses, reported S. Shahzad Mustafa, MD, of Rochester Regional Health in Rochester, New York, and colleagues . Three to four weeks after receiving the second dose, both patients had IgG antibodies against the spike protein of COVID-19, "suggesting vaccination was efficacious despite the graded dosing protocol," they wrote in Annals of Internal Medicine. One had no reaction to the second dose while the other experience some non-serious allergic symptoms.