Review details
Inclusion criteria were modified to focus on the Omicron variant by limiting eligible studies to only those enrolling patients on or after Nov. 26, 2021. The investigators included two randomized controlled trials and six retrospective cohort studies and ranked quality of evidence for the effectiveness of the following treatments, compared with usual care or no treatment: azithromycin, camostat mesylate, chloroquine-hydroxychloroquine, chlorpheniramine, colchicine, convalescent plasma, corticosteroids, ensitrelvir, favipiravir, fluvoxamine, ivermectin, lopinavir-ritonavir, molnupiravir, neutralizing monoclonal antibodies, metformin, niclosamide, nitazoxanide, nirmatrelvir-ritonavir, and remdesivir.
It compared results for all-cause and COVID-specific mortality, recovery, time to recovery, COVID hospitalization, and adverse and serious adverse events.
Nirmatrelvir-ritonavir was associated with a reduction in hospitalization caused by COVID-19 of 0.7% versus 1.2% (moderate certainty of evidence [COE]) and a reduction in all-cause mortality of less than 0.1% versus 0.2% (moderate COE).
Molnupiravir led to a higher recovery rate of 31.8% versus 22.6% (moderate COE) and a reduced time to recovery of 9 versus 15 median days (moderate COE). It had no effect, however, on all-cause mortality: 0.02% versus 0.04% (moderate COE). Nor did it affect the incidence of serious adverse events: 0.4% versus 0.3% (moderate COE).
“There have been no head-to-head comparative studies of these two treatments, but nirmatrelvir-ritonavir appears to be the preferred treatment,” Dr. Salvatore said. She noted that molnupiravir cannot be used in pregnant women or young persons under age 18, while nirmatrelvir-ritonavir carries the risk of drug interactions. Viral rebound and recurrence of symptoms have been reported in some patients receiving nirmatrelvir-ritonavir.
In other review findings, ivermectin had no effect on time to recovery (moderate COE) and adverse events versus placebo (low COE). Sotrovimab resulted in no difference in all-cause mortality, compared with no treatment (low COE). There were no eligible studies for all of the other treatments of interest nor were there any that specifically evaluated the benefits and harms of treatments for the Omicron variant.
The panel pointed to the need for more evaluation of the efficacy, effectiveness, and comparative effectiveness, as well as harms of pharmacologic and biologic treatments of COVID-19 in the outpatient setting, particularly in the context of changing dominant SARS-CoV-2 variants and subvariants.
Another area requiring further research is the effectiveness of retreatment in patients with previous COVID-19 infection. Subgroup analyses are also needed to assess whether the efficacy and effectiveness of outpatient treatments vary by age, sex, socioeconomic status, and comorbid conditions – or by SARS-CoV-2 variant, immunity status (prior SARS-CoV-2 infection, vaccination status, or time since infection or vaccination), symptom duration, or disease severity.
Dr. Salvatore agreed that more research is needed in special convalescent groups. “For instance, those with cancer who are immunocompromised may need longer treatment and adjunctive treatment with convalescent plasma. But is difficult to find a large enough study with 5,000 immunocompromised patients.”
Financial support for the development of the practice points came exclusively from the ACP operating budget. The evidence review was funded by the ACP. The authors disclosed no relevant high-level competing interests with regard to this guidance, although several authors reported intellectual interests in various areas of research. Dr. Salvatore disclosed no conflicts of interest relevant to her comments but is engaged in influenza research for Genentech.