DEATH; RESPIRATORY FAILURE; THROMBOSIS; COVID-19; GENERAL PHYSICAL HEALTH DETERIORATION; INTENSIVE CARE; POSITIVE AIRWAY PRESSURE THERAPY; SUSPECTED CLINICAL VACCINATION FAILURE; This spontaneous report received from a health care professional by a Regulatory Authority Vaccine Adverse Event Reporting System (VAERS) (VAERS ID 1923992) concerned an 82 year old male of unspecified race and ethnic origin. The patient's height, and weight were not reported. No past medical history or concurrent conditions were reported. The patient received covid-19 vaccine ad26.cov2.s (suspension for injection, route of administration was not reported, batch number: 1805025 expiry: Unknown) dose was not reported, 01 total administered in left arm on 12-MAR-2021 for an unspecified (unknown) indication. No concomitant medications were reported.  On 22-NOV-2021 the patient was admitted from nursing home with respiratory failure secondary to covid-19 infection (suspected clinical vaccination failure). He was admitted to the Intensive Care Unit (ICU) and placed on non-invasive ventilation (NIV). Patient continued to require more oxygen and was unable to come off bilevel positive airway pressure (BIPAP). He did expressed that he did not want to be placed on ventilator and did not want any intervention in regards to his own blood clot (thrombosis). The patient made a do-not-resuscitate (DNR) do not intubate (DNI) order. His family was contacted. Patient continued to decline over the next couple of days. Family was called in he was transitioned to comfort measures. The patient was hospitalized for 7 days discharge information was not reported. On 29-NOV-2021 at 18:46 the patient died from unknown cause of death. It was unknown if an autopsy was performed or not. The action taken with covid-19 vaccine ad26.cov2.s was not applicable. The outcome of respiratory failure, thrombosis, covid-19, general physical health deterioration, intensive care and positive airway pressure therapy were fatal, and the outcome of suspected clinical vaccination failure was unknown. This report was serious (Death, and Hospitalization Caused / Prolonged). This report was associated with product quality complaint: 90000208135. The suspected product quality complaint has been confirmed to be the reported allegation could not be determined. A manufacturing related root cause could not be identified based on the PQC evaluation/investigation performed.  Additional information was received from Central Complaint Vigilance on 25-JAN-2022. The following information was updated and incorporated into the case narrative: product quality complaint investigation result was added.; Sender's Comments: V1: Follow up information in this version updated Product quality complaint investigation result. The follow up information does not change the company causality of the previously reported events. 20211240520-COVID-19 VACCINE AD26.COV2.S-Death,  respiratory failure, thrombosis, covid-19, general physical health deterioration, intensive care and positive airway pressure therapy. This event(s) is considered unassessable. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There is no information on any other factors potentially associated with the event(s). 20211240520-COVID-19 VACCINE AD26.COV2.S-suspected clinical vaccination failure. This event(s) is considered not related. The event(s) has a compatible/suggestive temporal relationship, is unlabeled, and has unknown scientific plausibility. There are other factors more likely to be associated with the event(s) than the drug. Specifically: SPECIAL SITUATIONS.; Reported Cause(s) of Death: UNKNOWN CAUSE OF DEATH