The FDA gave emergency use authorization (EUA) to the COVID-19 vaccine developed by Janssen (Johnson & Johnson) on Feb. 27, and the next day, its use was recommended by the CDC's Advisory Committee on Immunization Practices. The vaccine, a replication-incompetent adenovirus type 26 vectored vaccine, is provided in a single intramuscular injection. According to briefing documents released by the FDA, the vaccine has been shown to be 66.9% effective at preventing laboratory-confirmed moderate to severe/critical COVID-19 at 14 days after vaccination. The vaccine trial reported seven COVID-19 related deaths in the placebo group and none in the vaccine group. The most common solicited adverse reactions were injection-site pain (48.6%), headache (38.9%), fatigue (38.2%), and myalgia (33.2%), and they were predominantly mild or moderate. The vaccine group had more cases of thromboembolic events (15 vs. 10) and tinnitus (6 vs. 0), but data were insufficient to determine a causal relationship. Nonfatal serious adverse events were similar between groups. One hypersensitivity reaction, which was not classified as anaphylaxis, began two days after vaccination and was likely related to the vaccine.
New data on the effectiveness of the Pfizer-BioNTech vaccine was published by the New England Journal of Medicine on Feb. 24. A comparison of more than 500,000 people vaccinated in Israel to matched unvaccinated controls found effectiveness after the first (14 to 20 days after) and second (7 days after) shots, respectively, of 57% and 94% for symptomatic COVID-19 and 62% and 92% for severe disease. The estimated effectiveness at preventing death from COVID-19 was 72% at 14 to 20 days after the first shot. The effect was generally consistent across subpopulations and age groups, although there was potentially slightly lower effectiveness in those with multiple comorbidities.
An outpatient antibody treatment for COVID-19 has gained the recommendation of the NIH's guideline panel. On Feb. 23, the panel recommended bamlanivimab, 700 mg, plus etesevimab, 1,400 mg, for the treatment of outpatients with mild to moderate COVID-19 who are at high risk of clinical progression. Treatment should be started as soon as possible after a patient tests positive and within 10 days of symptom onset, the guidance said. The panel recommends against using the treatment in patients who are hospitalized because of COVID-19, except in a clinical trial, but it should be considered for persons with mild to moderate COVID-19 who are hospitalized for a reason other than COVID-19, the statement said. The FDA issued an EUA for bamlanivimab plus etesevimab on Feb. 9.
The NIH also announced plans to study prolonged symptoms in patients who have had COVID-19 and gave this phenomenon an official name. “Often referred to as Long COVID, these symptoms, which can include fatigue, shortness of breath, brain fog, sleep disorders, fevers, gastrointestinal symptoms, anxiety, and depression, can persist for months and can range from mild to incapacitating,” said a Feb. 23 statement from NIH director Francis S. Collins, MD, PhD. “While still being defined, these effects can be collectively referred to as Post-Acute Sequelae of SARS-CoV-2 infection (PASC).” The NIH's new PASC Initiative will fund and collect research to try to better understand the long-term effects of COVID-19.