Mortality and risk factors of vaccinated and unvaccinated COVID-19 frail patients treated with anti-SARS-CoV-2 monoclonal antibodies. A real-world study

BACKGROUND

There is a scarcity of data on outcomes and predictors of therapeutic failure of mAbs in frail COVID-19 patients.

METHODS

Prospective study including consecutive COVID-19 outpatients referred by primary care physicians for mAbs treatment. Outcomes evaluated were 60-day mortality, time to SARS-CoV-2 clearance, need for hospitalization, and O₂-therapy.

RESULTS

Among 1026 COVID-19 patients enrolled, 60.2% received casirivamab/imdevimab and 39.8% sotrivimab. Median age was 63 years, 52.4% were males and median time from positive nasopharyngeal swab to mAbs administration was 3 days [IQR, 2-5]. 78.1% were vaccinated. Overall, 60-day mortality was 2.14%. No differences in outcomes were observed between the two mAbs used. No difference was observed in mortality between vaccinated and unvaccinated patients (p=0.925), although lower rate of hospitalization (p<0.005), less need for O₂-therapy (p<0.0001) and reduced nasopharyngeal swab negativity time (p<0.0001) were observed in vaccinated. Early administration of mAbs was associated with lower mortality (p<0.007), while corticosteroid use worsened prognosis (p<0.004). Independent predictors associated with higher mortality were older age (p<0.0001), presence of active haematological malignancies (p<0.0001), renal failure (p<0.041) and need for O₂-therapy (p<0.001).

CONCLUSION

This study shows similar effectiveness among mAbs used regardless of vaccination status and identifies COVID-19 patients in whom mAbs have poor activity.

Non-invasive respiratory support in SARS-CoV-2 related acute respiratory distress syndrome: when is it most appropriate to start treatment?

BACKGROUND

Acute respiratory distress syndrome (ARDS) is one of the most severe complications of SARS-CoV-2 infection. Non-Invasive Respiratory Support (NRS) as Continuous Positive Airway Pressure (CPAP) and/or Non-Invasive Ventilation (NIV) has been proven as effective in the management of SARS-CoV-2-related ARDS. However, the most appropriate timing for start NRS is unknown.

METHODS

We conducted a prospective pilot study including all consecutive patients who developed moderate SARS-CoV-2-related ARDS during hospitalization. Patients were randomly divided into two intervention groups according to ARDS severity (assessed by PaO₂/FiO₂-P/F) at NRS beginning: group A started CPAP/NIV when P/F was ≤ 200 and group B started CPAP/NIV when P/F was ≤ 150. Eligible patients who did not give their consent to CPAP/NIV until the severe stage of ARDS and started non-invasive treatment when P/F ≤ 100 (group C) was added. The considered outcomes were in-hospital mortality, oro-tracheal intubation (OTI) and days of hospitalization.

RESULTS

Among 146 eligible patients, 29 underwent CPAP/NIV when P/F was ≤ 200 (Group A), 68 when P/F was ≤ 150 (Group B) and 31 patients agreed to non-invasive treatment only when P/F was ≤ 100 (Group C). Starting NRS at P/F level between 151 and 200 did not results in significant differences in the outcomes as compared to treatment starting with P/F ranging 101-150. Conversely, patients undergone CPAP/NIV in a moderate stage (P/F 101-200) had a significantly lower in-hospital mortality rate (13.4 vs. 29.0%, p = 0.044) and hospitalization length (14 vs. 15 days, p = 0.038) than those in the severe stage (P/F ≤ 100). Age and need for continuous ventilation were independent predictors of CPAP/NIV failure.

CONCLUSIONS

Starting CPAP/NIV in patients with SARS-CoV-2-related ARDS in moderate stage (100 > P/F ≤ 200) is associated to a reduction of both in-hospital mortality and hospitalization length compared to the severe stage (P/F ≤ 100). Starting CPAP/NIV with a P/F > 150 does not appear to be of clinical utility.