Longitudinal importance of the soluble receptor for advanced glycation end-products in nonintubated hospitalized patients with COVID-19 pneumonia

The soluble receptor for advanced glycation end-products (sRAGE) is a marker of alveolar type I cell injury associated with outcomes in COVID-19 pneumonia. How plasma sRAGE changes over time and whether it remains associated with long-term clinical outcomes beyond a single measurement in COVID-19 have not been well studied. We studied two cohorts in randomized clinical trials of monoclonal antibody treatment for COVID-19 (bamlanivimab and tixagevimab/cilgavimab). We first studied the association between baseline plasma sRAGE and 90-day clinical outcomes, which had been previously demonstrated in the bamlanivimab cohort, among hospitalized patients with COVID-19 supported with high-flow nasal oxygen (HFNO) or noninvasive ventilation (NIV) in the tixagevimab/cilgavimab study. Next, we investigated the relationship between day 3 sRAGE and 90-day outcomes and how plasma sRAGE changes over the first 3 days of hospitalization in both clinical trial cohorts. We found that plasma sRAGE in the highest quartile in the HFNO/NIV participants in the tixagevimab/cilgavimab trial was associated with a significantly lower rate of 90-day sustained recovery [recovery rate ratio ¼ 0.31, 95% confidence interval (CI) ¼ 0.14–0.71, P ¼ 0.005] and with a significantly higher rate of 90-day mortality (hazard ratio ¼ 2.49, 95% CI ¼ 1.15–5.43, P ¼ 0.021) compared with the lower three quartiles. Day 3 plasma sRAGE in both clinical trial cohorts remained associated with 90-day clinical outcomes. The trajectory of sRAGE was not influenced by treatment assignment. Our results indicate that plasma sRAGE is a valuable prognostic marker in COVID-19 up to 3 days after initial hospital presentation.