Updated: October 30, 2024
Epidemiology
Transmission
Symptoms: range from asymptomatic to life-threatening. Most symptomatic illness begins with URTIs. Severe infection is seen chiefly in the elderly, those with multiple comorbidities and the immunocompromised.
Laboratory and imaging findings (severe disease)
Differential diagnosis
COVID-19 testing: Though testing remains encouraged for all patients, the FDA removed from their EUAs (2/3/23) the requirement for nirmatrelvir/ritonavir or molnupiravir to have a confirmed SARS-CoV-2 infection. Though it is still recommended to test by antigen or molecular assays, there may be circumstances, such as known confirmed household exposure, that clinicians may diagnose COVID without a test in hand.
Other candidate antiviral therapies: only widely discussed drugs are listed below (see Table for a more complete list and references)
Respiratory Support at Randomization | Dexamethasone | Usual Care |
*Statistically significant | ||
No oxygen received | 17.0% | 13.2% |
Oxygen only* | 21.5% | 25.0% |
Invasive mechanical ventilation* | 29.0% | 40.7% |
Other corticosteroids were potentially beneficial in other trials, and meta-analyses had a summary OR 0.66 on 28d all-cause mortality[21].
Convalescent plasma (CP) serum-containing neutralizing antibodies against SARS-CoV-2, preferably using high-titer plasma (defined as a ≥250 titer in the Broad Institute’s neutralizing antibody assay or an S/C cutoff of ≥12 in the Ortho VITROS IgG assay)
Monoclonal antibodies (mAbs) specific to SARS-CoV-2
Drug | Recommendation |
Monoclonal inhibitor of IL-1 granted EUA status for treating severe COVID-19 pneumonia with a risk of progressing in hospitalized patients. The SAVE-MORE RCT showed sufficient efficacy (reduction by 11-pt WHO clinical progression at d28, 0.36 (95% confidence interval 0.26–0.50 compared to placebo) and safety, but enrollment was dependent on elevations of soluble urokinase plasminogen activator receptor levels (uPAR ≥6 ng ml−1), a test not routinely available in the US. It can be considered in use similar to the employment of tocilizumab in treating progressive COVID-19 pneumonia in hospitalized patients. It is not currently a recommended treatment for COVID-19, but it is available if shortages of other drugs, such as tocilizumab or JAK inhibitors, exist. | |
The second fully FDA-approved treatment for severe COVID-19 (after remdesivir) is a selective inhibitor of Janus kinase (JAK) 1 and 2, FDA-approved for rheumatoid arthritis, studied for COVID-19 in ACTT-2 studying RDV v. RDV + baricitinib. The drug offered a one-day improvement in symptom resolution, which has led to FDA EUA. Upon subgroup analysis, the drug worked based on the ordinal 6 group (high-flow oxygen or non-invasive ventilation). These patients had a time to recovery of 10 days with combination treatment and 18 days with control (rate ratio for recovery, 1.51; 95% CI, 1.10 to 2.08). The drug might be considered for use in patients who cannot receive dexamethasone but who require high-flow oxygen or non-invasive ventilation. COV-BARRIER RCT with baricitinib vs. standard of care (19% received RDV, 79.3% on corticosteroids, which differs from ACTT-2 trial). The composite primary endpoint (death, progression to high flow O2, NIMV, MV or ECMO) was insignificant. The secondary endpoint 28d all-cause mortality 8.1% v 13.1%, a 38% reduction (HR 0.57 (95% CI 0.41-0.78) was not otherwise explained by the findings specifically, i.e., since the primary endpoint was not reached, no difference in groups regarding clots, MIs, CVA, etc.). Impressive mortality reduction; however, the study was more international than the US, and only a minority received RDV. Recent studies (COV-Barrier subset analysis and Recovery) on dexamethasone showed mortality reduction benefits in critically ill patients. | |
We are still waiting for a large RCT to be published to confirm hospital use; however, it is now the only antibody product available to use in people with COVID-19 and high-risk immunosuppressed, especially if vaccine non-responders/pts with B cell disorders. However, many trials used the agent too late (e.g., RECOVERY, others) in hospitalized patients for there to be a chance of helping patients in later phases of infection. Convalescent plasma works best as an antiviral. The current FDA EUA for outpatients and hospitalized patients now enforces high-titer plasma, which is only available for immunosuppressed populations. It is best used within three days of illness onset or the first three days of hospitalization. Now indicated only for immunosuppressed populations. High titer units from people who have recovered from COVID-19 and have been immunized appear to generate the best titers and activity against known circulating variants, including Omicron. An outpatient study of early plasma administration showed a 54% reduction in hospitalization, demonstrating that high-titer units have a role if used early rather than late (in hospital) for average, high-risk patients[8]. NIH guidance has softened slightly with the lack of RCTs and acknowledges use in certain populations. | |
Dexamethasone | The RECOVERY trial provides the first evidence of therapy that provides a mortality benefit to those mechanically ventilated (or who require oxygen, severe COVID-19). In this trial, there was a trend toward increased mortality in those who do not require oxygen, so it was not recommended in this group, usually with early infection. By the numbers, the rate ratio of mortality at 28d was 0.65 (p=0.0003) for those mechanically ventilated, 0.8 (p=0.0021) for severe COVID-19 patients who needed non-invasive supplemental oxygen, but 1.22 (p=0.14; so higher mortality trend) for patients who did not require supplemental oxygen. Some aspects of the RECOVERY trial deserve comment: the UK trial mortality was unusually high if the same benefit would be witnessed in North America is unclear. Also, patients with less than 7d of symptoms appeared not to benefit, suggesting no impact or potential harm during the early phase of viral illness (similar to influenza). Still, the benefit is seen in the later hyperinflammatory phase. This trial was open-label, but the mortality endpoint would tend to discount bias to a substantial degree. Women appeared to benefit less from dexamethasone than men. |
High hopes for this nucleoside analog; however, the MOVe-OUT trial had only ~ 30% reduction in hospitalization or death within the first month when used in outpatients with fewer than 5 days of symptoms. Some have voiced concerns about mutagenesis and driving new viral variants with high use levels, although with only a five-day course, the mutagenesis concern seems lower. Regardless, this drug is clearly in a lower tier than Paxlovid. The drug should not be used in children, adolescents, pregnant and breastfeeding women. It has few drug interaction issues or side effects from the treatment. | |
A combination drug is an oral protease inhibitor that has activity against SARS-CoV-2. Results from the outpatient COVID-19 EPIC trial are impressive for treatment of early COVID-19; if given within the first 3 to 5 days of symptoms, reduced hospitalization or death by 88-89%. The ease of oral administration will make this the preferred route for many compared to injectable monoclonal antibodies. Problems of limited supply in early 2022 have diminished. The use of ritonavir means that prescribers should carefully assess drug-drug interactions. NIH Guidance has suggested this drug is safe to use for pregnant women. | |
Similar to Evusheld, it has a long life, thereby requiring 3-month infusions for moderately to severely immunosuppressed people who are unlikely to respond well to immunization. Changing Omicron variants may mean a short lifespan for this monoclonal agent. It is very expensive and poses issues with administration due to the risk of anaphylaxis, prompting prolonged observation times. | |
The ACTT1 results showed improved LOS by 4 days in patients receiving RDV. The average duration of symptoms before enrollment was 9d median with a wide range. The key observation from data is that benefit was derived in patients who were started before mechanical ventilation, suggesting that using the drug earlier in the disease course has efficacy--consistent with its mechanism of action as an antiviral. Some argue that SOLIDARITY and DisCoVeRy trials show no mortality benefit, although the latter trial did have a similar benefit for patients on oxygen as ACTT-1. Many US and NIH guidelines favor continued use for patients with severe COVID-19 requiring oxygen but not admitted to the ICU due to improvement in LOS noted by prospective and several retrospective, matched control studies. PINETREE data suggested that early administration (< 5d after symptom onset) in patients at high risk for COVID-19 prevents hospitalization and death. Three-day infusion poses logistical challenges compared to single-dose mAb for outpatients. Still, maybe the treatment of choice for those patients ineligible for Paxlovid and if effective mAb is unavailable. RDV is the first to receive full FDA approval for COVID-19, and use in the outpatient arena often requires financial clearance before receiving since it is now paid by patient insurance; this may slow the time to the first infusion. It has been increasingly used for outpatient treatment since the removal of bebtelovimab. | |
This anti-IL6R mAb has had an up-and-down and now up history for COVID-19. The drug appears to not work as monotherapy; however, when combined with dexamethasone, it reduces the severity and duration of illness and mortality in three studies: EMPACTA, REMAP-CAP, and RECOVERY. Endorsed for use by NIH and IDSA for patients on high-flow 02 or first 24h of ICU care--baricitinib is an alternative. Either should be combined with dexamethasone or another corticosteroid. Baricitinib is an alternative employed by some institutions in the second half of 2021 due to supply shortfalls of tocilizumab. | |
The drug is a chimeric human/mouse immunoglobulin G4 (IgG4) antibody consisting of mouse anti-human complement factor 5a (C5a) monoclonal binding sites (variable regions of heavy and light chain regions) and human gamma 4 heavy chain and kappa light chain constant regions. In the FDA prescribing information, the drug is positioned as an alternative to baricitinib, remdesivir and tocilizumab. Given EUA approval based on Phase 3 RCT severe COVID-19 requiring IMV or ECMO showing reduced mortality with high rates of nonfatal SAEs including pneumonia (18.9% v. 12.8%), sepsis (14.9% v. 7.4%) and septic shock (9.1% v. 7.4%). Place in COVID-19 care is uncertain, and no national guideline (e.g., NIH or IDSA) has yet weighed in. |
Comment: Regularly updated and now the lead guideline since the retirement of the NIH panel. One central area where our JH guide differs is in convalescent plasma use, which we at JH believe has a role in early illness in hospitalized patients (< 3d) or in some severely immunosuppressed patients who cannot generate meaningful antibody responses and now has a more significant role that monoclonal antibodies are no longer available. The availability of high-titer convalescent plasma remains limited for many.
Comment: Unfortunately, this large cohort examined did not find any useful combination of commercially available lab tests that could sufficiently identify people with long COVID.
Comment: Antigen testing is now in the sensitivity range similar to influenza RIDTs. The overall sensitivity of daily antigen testing was only 47% but rose to 77% on days of fever. If people were asymptomatic, it was only 18%.
Comment: This cohort study suggests that those with at least one risk factor for COVID-19 had a reduced risk of ~ 25% for long COVID if they took the antiviral protease inhibitor.
Comment: An elegant study including viral cultures, done first early in the pandemic and then later on, but not in a well-immunized population, found that while 61% remained with culturable virus ≥ 6 days after symptom onset, household transmission mainly occurred < 6d. This is to keep in mind that high viral load is a factor in viral transmission, often when people are asymptotic.
Comment: One of many articles written on this subject. Without surprise now 4 years (2024) from the pandemic onset, it is doubtful we’ll know for sure without more disclosure from the Chinese government.
Comment: Many academic centers employ CP +/—other agents such as RDV for their immunodeficient, hospitalized COVID patients. This population has not been as well studied, and CP has been unfairly maligned due to negative trials in other populations that probably would not benefit from late administration. This meta-analysis shows a mortality benefit, suggesting that some populations benefit from antibodies against the virus.
Comment: Though convalescent plasma is now limited by the FDA to immunosuppressed patients, this RCT of early administration of high-titer convalescent plasma showed a 54% reduction in hospitalization within 28d of symptom onset.
Comment: A trial in unimmunized patients with mild-moderate COVID-19 found an 87-88% reduction in hospitalization or death compared to placebo. The drug is relatively well-tolerated. Its Achilles heel is co-packaging with ritonavir to boost nirmtrelavir levels, the SARS-CoV-2 specific protease inhibitor. Ritonavir, with its suicide inhibitor impact on CYP3A4, knocks out many patients who are on medications such as tacrolimus. We need to check for drug interactions. Patients on statins can have the drug held for the 5-day course.
Comment: It was disappointing that the efficacy fell to 30% from the preliminary 50% impact at reducing hospitalization or death in this study of mild-moderate COVID-19 in unimmunized patients. The drug has a clean slide effect profile. Much has been made of genotoxicity concerns, but the impact is not clear from a 5d course. Check for pregnancy in women of childbearing age. Notably, fewer deaths in the molnupiravir arm, but not statistically significant. Probably worthwhile in patients at high risk for disease progression, and at least in early 2022 is the easiest to procure and take compared to other outpatient medications for COVID-19.
Comment: Experience from early in the pandemic (2020) found some false positives, usually either procurement error or low viral levels, often at later stages of the illness.
Comment: Pragmatic trial, and it is also essential to note the extraordinarily high background mortality in the U.K. at the time (~40%). 28-day mortality in the usual care group was highest in those patients receiving IMV (40.7%), intermediate in those receiving oxygen only (25.0%), and lowest among those who were not receiving respiratory support at randomization (13.2%). The most significant absolute reductions in 28-day mortality were seen in the sickest patients, and subgroup analysis suggests in those > 7d of symptoms that would correlate with the inflammatory phase. Dexamethasone improves 28d mortality compared to placebo in patients requiring IMV (NNT = 8.5) and those requiring oxygen therapy (NNT = 29). There was no benefit to patients not requiring oxygenation support and even a signal for harm.
Comment: High-titer convalescent plasma was not helpful in this trial of 511 patients who received it < 7d from the onset of symptoms. The average duration of symptoms in the active arm was 4 days (median IQR).
Comment: A subset of patients in the expanded access use of COVID-19 convalescent plasma found that high titer recipients who received units before critical illness had a lower risk of death than those with low titer plasma.
Comment: Small but well-done double-blind RCT of patients > 65 yrs with mild COVID-18 and less than three days of symptoms. A total of 160 patients found that severe respiratory disease developed in 13 of 80 patients (16%) who received convalescent plasma and 25 of 80 patients (31%) who received placebo (relative risk, 0.52; 95% confidence interval [CI], 0.29 to 0.94; P = 0.03), with a relative risk reduction of 48%. A modified intention-to-treat analysis that excluded six patients with a primary end-point event before infusion of convalescent plasma or placebo showed a larger effect size (relative risk, 0.40; 95% CI, 0.20 to 0.81). No solicited adverse events were observed. The study is the best evidence that you need high titer units and early administration to have an effect.
Comment: Helpful data synthesis of major tocilizumab trials. Data overall is mixed; there may be efficacy but nothing like that suggested from observational trials--at least for immunomodulatory monotherapy tocilizumab. The author suggests waiting for more RCT data to determine if the drug is helpful for COVID-19 patients. This paper included EMPACTA; however, not RECOVERY or REMAP-CAP, which has defined a difference between dexamethasone + tocilizumab vs. tocilizumab monotherapy.
Comment: Called a positive trial for tocilizumab, essential points are that 1) statistical significance only when the rate of progressing to mechanical ventilation is included (not just mechanical ventilation and death as hard endpoints) and 2) > 80% of patients also received dexamethasone, suggesting that the two drugs need to work together to help patients.
Comment: The ACTT1 results that showed improved LOS by 4 days in patients receiving RDV. The average duration of symptoms prior to enrollment was 9d median with a wide range. The key observation from data is that benefit was derived in patients who were started prior to mechanical ventilation, suggesting that the use of the drug earlier in the disease course has efficacy--consistent with its mechanism of action as an antiviral. Final results are now available.
Comment: A series of 1217 specimens analyzed for respiratory viruses found 116/1217 specimens (9.5%) were positive for SARS-CoV-2, and 318 (26.1%) were positive for one or more non–SARS-CoV-2 pathogens. Within the SARS-CoV-2 positive specimens, 24 (20.7%) were positive for one or more additional pathogens. The most commonly detected co-infections were rhinovirus/enterovirus (6.9%), respiratory syncytial virus (5.2%), and non–SARS-CoV-2 Coronaviridae (4.3%). This report yielded higher viral co-pathogen rates than earlier COVID-19 studies but similar to the co-infection rates of many standard respiratory viral illnesses. Finding a virus other than SARS-CoV-2 should not be grounds for concluding that COVID-19 is not present.
Comment: Notes that false negatives were very common in the early phases of the pandemic (reports of 27% early Chinese experience) and ranged from 2-29% in five other studies.
Comment: Seven randomized trials included 1703 patients, of whom 647 died. 28-day all-cause mortality was lower among patients who received corticosteroids than those who received usual care or placebo (summary odds ratio, 0.66). Dexamethasone and hydrocortisone had similar impacts, while the single methylprednisolone trial had less effect on mortality.
Comment: Though the open-label trial was cited as a reason to use 5-day instead of 10-d RDV for severe COVID-19, the fact that the 10-d course did worse without notably more side effects is concerning that the 5d data are perhaps not as solid. Also, the FDA cites this trial as a reason (along with ACTT-1) to expand RDV use to those hospitalized but not needing oxygen; however, NNT =~100, and limited patients not requiring oxygen at randomization are included.
Comment: Chest CT shows early ground-glass infiltrates, which may offer a speedier "diagnosis" than PCR studies in an epidemic setting as a first finding if molecular assays were not readily available.
Comment: Authors report on patients in earlier phases of COVID-19 infection; 20 (33.9%) reported at least one taste or olfactory disorder and 11 (18.6%) both. This is not unique, though, as other viral respiratory infections may also cause these symptoms.
Comment: The paper suggests that some patients presented with GI symptoms as part of COVID-19, 11.4% of 651 in this study from Zhejiang University in Hangzhou. A caveat is their definition of GI included nausea only in addition to diarrhea and vomiting, as they only needed one of the three to qualify for GI symptoms. They also suggested that patients who had GI had more severe COVID infection.
Comment: A small but well-conducted study looks at 9 cases, with most patients on day 1 having mild or prodromal symptoms. Key findings include finding the virus in upper respiratory tissues with no difference between nasopharyngeal and oropharyngeal speeding, which was very high during the first week of illness but not in the stool. Viral RNA remained in the sputum beyond the resolution of symptoms. Seroconversion occurred by day 7 in 50% of patients but by day 14 in 100%. Despite the knowledge gained about viral kinetics, this paper proves that illness may also present as a routine upper respiratory tract infection without pneumonia or lower tract symptoms.
Comment: One of the initial significant reports of the Wuhan COVID-19 epidemic. In this series, the median age was 56 and slightly more men (54%) were affected. Predominant symptoms include fever, fatigue and dry cough. Leukopenia was seen in ~70%. Thirty-six patients (26.1%) were transferred to the intensive care unit (ICU) because of complications, including acute respiratory distress syndrome (22 [61.1%]), arrhythmia (16 [44.4%]), and shock (11 [30.6%]).
Comment: An early report includes electron microscopy photomicrographs and sequence analysis of what is now termed COVID-19 disease and SARS-2-CoV virus.