New COVID-19 treatment, monitoring, isolation guidance

The Infectious Diseases Society of America newly suggested tocilizumab for some patients, while the CDC offered guidance on isolation duration for immunocompromised patients and pulse oximetry accuracy and published safety data on the currently available vaccines. Recent studies looked at vitamin D and anticoagulation in COVID-19.

The Infectious Diseases Society of America (IDSA) reversed its guidance on use of tocilizumab in patients hospitalized with COVID-19. As of Feb. 22, the IDSA conditionally suggests use of tocilizumab in addition to standard of care (i.e., steroids) rather than standard care alone in patients with progressive severe or critical COVID-19 and elevated markers of systemic inflammation. (Severe is defined as an oxygen saturation of 94% or below on room air, including patients on supplemental oxygen. Critical includes patients on mechanical ventilation or extracorporeal mechanical oxygenation.) The recommendation notes that in the largest trial of tocilizumab, the criterion for systemic inflammation was a C-reactive protein level of 75 mg/L or above. Previously the IDSA conditionally suggested against use of tocilizumab in hospitalized patients with COVID-19.

The CDC made multiple small updates to its guidance on COVID-19. On Feb. 18, it alerted clinicians that some severely immunocompromised persons with COVID-19 may remain infectious beyond 20 days after their symptoms began and require additional testing and expert consultation before they leave isolation. On Feb. 12, the agency encouraged clinicians to be aware that pulse oximeters may exhibit suboptimal accuracy in certain populations. The guidance cites a study that found occult hypoxemia went undetected by pulse oximetry nearly three times more frequently in hospitalized Black patients than White patients. The FDA issued a safety communication on the same topic on Feb. 19, urging clinicians to be aware of the many factors that can affect accuracy (including poor circulation, skin pigmentation, skin thickness, skin temperature, current tobacco use, and use of fingernail polish) and make decisions based on trends rather than absolute thresholds.

The first month of COVID-19 vaccine safety monitoring found relatively few adverse events, according to a CDC report published Feb. 19 in MMWR. From Dec. 14, 2020, to Jan. 13, 2021, more than 13 million doses were administered. During that time, 6,994 adverse events were reported to the national database, of which, 90.8% were classified as nonserious. The most frequent adverse events were headache (22.4%), fatigue (16.5%), and dizziness (16.5%). More reactions were reported after the second dose of Pfizer-BioNTech than the first (data on the second dose of the Moderna vaccine were not available). There were 62 confirmed reports of anaphylaxis, 46 after receipt of the Pfizer-BioNTech vaccine and 16 after receipt of the Moderna vaccine. A total of 113 deaths were reported after vaccination, and information from death certificates, autopsy reports, medical records, and clinical descriptions did not suggest a causal relationship. “These initial findings should provide reassurance to health care providers and to vaccine recipients and promote confidence in the safety of COVID-19 vaccines,” the CDC said.

In the latest research on COVID-19 therapeutics, Vitamin D3 did not improve outcomes in hospitalized patients with COVID-19, according to a study published by JAMA on Feb. 17. It included 240 Brazilian patients, half of whom were randomized to a single oral dose of 200,000 IU of vitamin D3 and half who were randomized to placebo. There were no significant differences between groups in median length of stay, in-hospital mortality, ICU admission, or need for mechanical ventilation. Mean serum levels of 25-hydroxyvitamin D were higher in the active treatment group (44.4 ng/mL vs. 19.8 ng/mL), suggesting that higher levels do not help. “The findings do not support the use of a high dose of vitamin D3 for treatment of moderate to severe COVID-19,” the authors concluded, although they cautioned that the results cannot necessarily be extrapolated to other geographic regions, which could have more vitamin D deficiencies.

However, prophylactic anticoagulation for inpatients with COVID-19 gained additional evidence support from a study published by The BMJ on Feb. 11. It included 4,297 patients admitted to Veterans Health Administration hospitals. Prophylactic anticoagulation was provided within 24 hours of admission to 84.4% of the patients (almost entirely subcutaneous heparin or enoxaparin). Mortality at 30 days was 14.3% in those who received prophylactic anticoagulation versus 18.7% in those who did not (hazard ratio, 0.73; 95% CI, 0.66 to 0.81). Patients who received prophylaxis also had lower rates of inpatient mortality and therapeutic anticoagulation and no increase in bleeding requiring transfusion. The authors noted that the benefit seemed to be greater among patients who weren't admitted to the ICU within 24 hours of hospital admission. “Our results provide strong real world evidence to support guidelines recommending the use of prophylactic anticoagulation as initial treatment for patients with covid-19 on hospital admission,” they said.