ACUTE HYPOXEMIC RESPIRATORY FAILURE; RIGHT HIP INTERTROCHANTERIC PROXIMAL FEMUR FRACTURE; CLOSED FRACTURE OF LEFT PROXIMAL HUMERUS; CLOSED FRACTURE OF MULTIPLE RIBS OF RIGHT SIDE; This 73 -year-old, male subject was participating in Study and experienced right hip intertrochanteric proximal femur fracture, closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, and acute hypoxemic respiratory failure.   The subject's medical history, as provided by the investigator, included focused seizures, hypertension, stroke, moderate lower back pain, and chronic obstructive pulmonary disease. Concomitant medications included lamotrigine, metoprolol, acetylsalicylic acid, multivitamin NOS, and terbinafine 1%.   The subject was randomized to receive intramuscular (dosed on 17 Sep 2020 and 19 Oct 2020) and was unblinded on 26 Jan 2021. The subject consented to receive mRNA-1273 for SARS-CoV-2 vaccination after being unblinded and, prior to event onset, the subject received mRNA-1273 (Dose 3, booster) SARS-CoV-2 vaccination on 03 Dec 2021, approximately 4 months 26 days before onset of the event.  On 28 Apr 2022, the subject experienced right hip intertrochanteric proximal femur fracture. The subject's girlfriends notified the site that the subject had been hospitalized due to a broken hip. Open reduction and internal fixation was performed.  On 29 Apr 2022, the subject experienced acute hypoxemic respiratory failure likely due to chronic obstructive pulmonary disease (COPD) and fluid overload from intravenous fluids. Treatment medications included furosemide, antibiotics, and a nebulizer. He improved after three days.   On 06 May 2022, the subject was discharged from the hospital to a skilled nursing facility. He was discharged on 4 liter home oxygen.  On 11 May 2022, the subject experienced closed fracture of multiple ribs of right side and closed fracture of left proximal humerus. It was reported the subject missed a step which caused him to fall. The subject spent two days in the intensive care unit. He underwent intermedullary nailing of his left humerus and rib pain was controlled with oral pain medications.   On 16 May 2022, the subject was discharged from the hospital.  The subject received all scheduled doses of study drug prior to the event; therefore, action taken with study drug in response to the event was not applicable.  The event, closed fracture of multiple ribs of right side, was reported as resolving.  The event, right hip intertrochanteric proximal femur fracture, was reported as resolved on 29 Apr 2022.  The event, acute hypoxemic respiratory failure, was reported as resolved on 02 May 2022.  The event, closed fracture of left proximal humerus, was reported as resolved on 13 May 2022.  The investigator assessed the event, right intertrochanteric proximal femur fracture, closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, and acute hypoxemic respiratory failure as not related to study drug and not related to study procedure.  Follow-up received on 06 Jul 2022 and 11 Jul 2022 included event end date and outcome (right hip intertrochanteric proximal femur fracture), investigator causality to study drug and procedure (closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, acute hypoxemic respiratory failure), event severity grade (closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, acute hypoxemic respiratory failure), and medical history.   Company comment: This case concerns a 73 -year-old, White, male subject with a medical history of focused seizures, hypertension, stroke, moderate lower back pain and chronic obstructive pulmonary disease, who experienced the unlisted events of right hip intertrochanteric proximal femur fracture, closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, and acute hypoxemic respiratory failure. The event right hip intertrochanteric proximal femur fracture occurred 1 year 3 months 1 day after the first dose of mRNA-1273 administration and 4 months 26 days after the third and booster dose; the event acute hypoxemic respiratory failure occurred 1 year 3 months 2 days after the first dose of mRNA-1273 administration and 4 months 27 days after the third and booster dose, and the events closed fracture of multiple ribs of right side and closed fracture of left proximal humerus occurred 1 year 3 months 14 days after the first dose of mRNA-1273 administration, and 5 months 9 days after the third and booster dose. The event of closed fracture of multiple ribs of right side was reported as resolving, and the events acute hypoxemic respiratory failure, closed fracture of left proximal humerus and right hip intertrochanteric proximal femur fracture were reported as resolved. The sponsor considers the events closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, and acute hypoxemic respiratory failure as not related to IP in agreement with the investigator.  The events of closed fracture of multiple ribs of right side and closed fracture of left proximal humerus were accidental in nature as these were secondary to a fall and the event acute hypoxemic respiratory failure might be explained by fluid overload from intravenous fluids in the context of a subject with chronic obstructive pulmonary disease (as reported).; Reporter's Comments: This case concerns a 73 -year-old, White, male subject with a medical history of focused seizures, hypertension, stroke, moderate lower back pain and chronic obstructive pulmonary disease, who experienced the unlisted events of right hip intertrochanteric proximal femur fracture, closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, and acute hypoxemic respiratory failure. The event right hip intertrochanteric proximal femur fracture occurred 1 year 3 months 1 day after the first dose of mRNA-1273 administration and 4 months 26 days after the third and booster dose; the event acute hypoxemic respiratory failure occurred 1 year 3 months 2 days after the first dose of mRNA-1273 administration and 4 months 27 days after the third and booster dose, and the events closed fracture of multiple ribs of right side and closed fracture of left proximal humerus occurred 1 year 3 months 14 days after the first dose of mRNA-1273 administration, and 5 months 9 days after the third and booster dose. The event of closed fracture of multiple ribs of right side was reported as resolving, and the events acute hypoxemic respiratory failure, closed fracture of left proximal humerus and right hip intertrochanteric proximal femur fracture were reported as resolved. The sponsor considers the events closed fracture of multiple ribs of right side, closed fracture of left proximal humerus, and acute hypoxemic respiratory failure as not related.  The events of closed fracture of multiple ribs of right side and closed fracture of left proximal humerus were accidental in nature as these were secondary to a fall and the event acute hypoxemic respiratory failure might be explained by fluid overload from intravenous fluids in the context of a subject with chronic obstructive pulmonary disease (as reported).