COVID-19 Update #92 for 7/28/2021

​COVID-19 Vaccines
 
A 19,109 patient, British observational study described the effectiveness of COVID-19 vaccines against the Delta variant. The effectives of the Pfizer-BioNTech COVID-19 vaccine was estimated to be 88% after two doses and 67% with two doses of the AstraZeneca vaccine.
 
An analysis of data by Israeli researchers found the effectiveness of the Pfizer-BioNTech COVID-19 vaccine to be 91% to prevent severe disease and 88% to prevent hospitalizations. The vaccine had an estimated effectiveness of 41% to protect against symptomatic disease and 39% to prevent infection due to the Delta variant compared to an estimated 64% effectiveness at the beginning of July. 
 
COVID-19 Anti-Inflammatories
 
Mesoblast announced that in a 60-day, 222 patient, Phase III trial (NCT04371393), treatment with remestemcel-L added to standard of care (SOC) did not reduce all-cause mortality compared to SOC in ventilator-dependent patients with moderate to severe acute respiratory distress syndrome (ARDS) due to COVID-19. In a pre-specified analysis of 123 patients under age 65, remestemcel-L reduced mortality by 46% by day 60, but not in 94 patients 65 or older. The Data Safety Monitoring Board (DSMB) recommended the trial be stopped when an interim analysis of 30-day data for 180 patients found it unlikely the trial would achieve a 43% reduction in mortality at the target enrollment of 300 patients. The DSMB recommended the trial be completed with the 222 patients already enrolled.