COVID-19 pneumonia; Antibody test for the spike protein, a marker of vaccine responsiveness, was undetectable; This literature-non-study case was reported in a literature article and describes the occurrence of COVID-19 PNEUMONIA (COVID-19 pneumonia) in a 68-year-old male patient who received mRNA-1273 (Spikevax) for COVID-19 vaccination. The occurrence of additional non-serious events is detailed below.   LITERATURE REFERENCE: Severe COVID pneumonia and undetectable B cells after vaccination in patients previously treated with rituximab: a case series. Postgrad. Med.. 2022;134(2):239-43     Concurrent medical conditions included Interstitial lung disease. Concomitant products included RITUXIMAB, PREDNISONE, MYCOPHENOLATE SODIUM and NINTEDANIB for Interstitial lung disease.   On an unknown date, the patient received second dose of mRNA-1273 (Spikevax) (unknown route) 1 dosage form. On an unknown date, received first dose of mRNA-1273 (Spikevax) (unknown route) dosage was changed to 1 dosage form. On an unknown date, the patient experienced COVID-19 PNEUMONIA (COVID-19 pneumonia) (seriousness criteria hospitalization and medically significant) and VACCINE INDUCED ANTIBODY ABSENT (Antibody test for the spike protein, a marker of vaccine responsiveness, was undetectable). The patient was treated with DEXAMETHASONE for COVID-19 pneumonia, at an unspecified dose and frequency and REMDESIVIR for COVID-19 pneumonia, at an unspecified dose and frequency. At the time of the report, COVID-19 PNEUMONIA (COVID-19 pneumonia) was resolving and VACCINE INDUCED ANTIBODY ABSENT (Antibody test for the spike protein, a marker of vaccine responsiveness, was undetectable) outcome was unknown. Related    DIAGNOSTIC RESULTS (normal ranges are provided in parenthesis if available): On an unknown date, Antibody test: vaccine responsiveness was undetectable Antibody test for spike protein, a marker of vaccine responsiveness was undetectable.. On an unknown date, Flow cytometry: undetectable levels of cd19+/20+ showed undetectable levels of CD19+/20+ cells in his blood.     For mRNA-1273 (Spikevax) (Unknown), the reporter considered COVID-19 PNEUMONIA (COVID-19 pneumonia) and VACCINE INDUCED ANTIBODY ABSENT (Antibody test for the spike protein, a marker of vaccine responsiveness, was undetectable) to be related.    It was reported that the patient received his first of two doses of the vaccine four months after rituximab treatment and completed his second vaccine dose three and a half weeks later.   Nearly 8 weeks after being fully vaccinated and following 7 days of symptoms, patient tested positive for COVID-19 and required ICU admission. An ICU length of stay was 12 day. The patient received 15 day course of Dexamethasone and 10 day course of remdesivir and 3 doses of convalescent plasma. After 7 days on NC, he was admitted to the ICU for an escalating oxygen requirement necessitating HFNC. The patient remained on HFNC for 14 days before successfully wearing back to NC. On day 29 patient was discharged to a rehabilitation center on NC at 6 liters.  Company comment: This case concerns a 68-year-old male patient, on Rituximab, Prednisone, Mycophenolate Sodium and Nintedanib for Interstitial lung disease, who experienced unexpected, serious (Hospitalized, Medically significant) AESI of COVID-19 Pneumonia, approximately 8 weeks after completing two doses of mRNA-1273 vaccine.  The patient reportedly received Dose 1 of mRNA-1273 on unknown date and received Dose 2 three and a half weeks later.   Upon admission, antibody test for spike protein was undetectable.   The patient was reported to have been tested positive for COVID-19.  The patient was started with unknown doses and frequency of 15-day course of dexamethasone, prednisone, 10-day course of remdesivir, 3 doses of convalescent plasma.  He was started with Oxygen supplementation via nasal cannula and was eventually hooked to High flow Nasal cannula due to escalating oxygen requirement. At the time of the report, the event is resolving.  The patient's concurrent intake of Rituximab, Prednisone, Mycophenolate Sodium and Nintedanib, remain to be a confounder for the event.  The benefit-risk relationship of mRNA-1273 is not affected by this report.   Reporter did not allow further contact; Sender's Comments: This case concerns a 68-year-old male patient, on Rituximab, Prednisone, Mycophenolate Sodium and Nintedanib for Interstitial lung disease, who experienced unexpected, serious (Hospitalized, Medically significant) AESI of COVID-19 Pneumonia, approximately 8 weeks after completing two doses of mRNA-1273 vaccine.  The patient reportedly received Dose 1 of mRNA-1273 on unknown date and received Dose 2 three and a half weeks later.   Upon admission, antibody test for spike protein was undetectable.   The patient was reported to have been tested positive for COVID-19.  The patient was started with unknown doses and frequency of 15-day course of dexamethasone, prednisone, 10-day course of remdesivir, 3 doses of convalescent plasma.  He was started with Oxygen supplementation via nasal cannula and was eventually hooked to High flow Nasal cannula due to escalating oxygen requirement. At the time of the report, the event is resolving.  The patient's concurrent intake of Rituximab, Prednisone, Mycophenolate Sodium and Nintedanib, remain to be a confounder for the event.  The benefit-risk relationship of mRNA-1273 is not affected by this report