COVID-19 Update #104 for 10/14/2021

COVID-19 Booster Vaccines
 
In September, the FDA amended the EUA for the Pfizer-BioNTech COVID-19 Vaccine to allow a booster dose, given at least six months after completion of the second dose to patients 65 years and older or who are at high risk for severe COVID-19, which includes healthcare professionals, frontline workers and people that live in group settings. The CDC agreed and also recommended a booster dose for these groups.
 
Today, Thursday, October 14, 2021, the FDA’s Vaccines and Related Biological Products Advisory Committee will discuss a booster dose for the Moderna COVID-19 vaccine. The next day the Advisory Committee will discuss J&J vaccine booster doses.
 
FDA reviews of booster doses of Moderna’s and Johnson & Johnson’s COVID-19 vaccines, suggested that while some evidence suggest a decrease in efficacy over time for symptomatic and Delta variant infections, the vaccines still provide protection against severe COVID-19 disease and death. The J&J review did note that higher efficacy with the mRNA vaccines. The FDA did not find any safety issues or increased reactogenicity with booster doses for either vaccine.

• Moderna is requesting an amendment to their EUA allowing the use of a half-dose (50mcg vs 100 mcg) as a booster, given at least 6-months after the primary series is completed in patients 65 or older or those 18 and older at high risk of severe COVID-19.
• Johnson & Johnson is requesting an amendment to their EUA allowing a booster given 2 to 6 months after initial immunization to patients 65 or older or those 18 and older at high risk of severe COVID-19. J&J recommends a booster at 2 months for high-risk patients or a 6-month booster to increase durability of protection.​

COVID-19 Vaccines
 
Sanofi announced interim results from a trial where Sanofi’s Fluzone High-Dose Quadrivalent vaccine and Moderna’s COVID-19 mRNA investigational booster were co-administered. Immunogenicity and safety for both vaccines were similar to what is seen with either vaccine administered alone.
 
COVID-19 Antibodies
 
AstraZeneca announced that in the 29-day, 903 patient, Phase III, TACKLE trial (NCT04723394), 4.4% of patients treated with AZD7442, a monoclonal antibody combination of tixagevimab and cilgavimab, progressed to severe COVID-19 or died compared to 8.9% with placebo in COVID-19 patients at high risk of progression to severe disease.
 
COVID-19 Antivirals
 
Azithromycin: In vitro evidence suggested potential activity of azithromycin against SARS-CoV-2, but clinical trials have not found a benefit. NIH recommends against the use of azithromycin with or without chloroquine or hydroxychloroquine in the treatment COVID-19.

• The 14-day, 263 patient, Phase III, ACTION trial (NCT04332107) was terminated early after an interim analysis failed to find an increase in symptom free days or hospitalizations at 21 days with azithromycin compared to placebo in outpatients with COVID-19
• In the 28-day, 292 patient, Phase III, ATOMIC2 trial (NCT04381962), treatment with azithromycin did not decrease hospitalization or mortality compared to placebo (10% vs 12%) in outpatients with COVID-19.
• In the 28-day, 1,323 patient, Phase III, PRINCIPLE trial, treatment with azithromycin did not decrease the percentage of patients recovered (80% vs 77%), hospitalized (3% each) or who died (0% each) compared to placebo in outpatients with COVID-19 at high risk to progress to more severe disease.