Fostamatinib showed no significant improvement in oxygen-free days for hospitalized adults with COVID-19 infections and hypoxemia, according to a recent study.
In the multicenter, double-blind, randomized phase III clinical trial, published in JAMA Network Open, researchers evaluated the efficacy of fostamatinib, a spleen tyrosine kinase inhibitor, in hospitalized adults with COVID-19 infections and hypoxemia during the Omicron era. The study was conducted from November 2021 to September 2023 across 41 U.S. and 21 international sites. A total of 400 participants were randomly assigned to receive fostamatinib (n = 199) or placebo (n = 201).
Participants, aged 18 years or older, had confirmed SARS-CoV-2 infections with hypoxemia, defined as oxygen saturation less than 92% on room air or requiring supplemental oxygen. The intervention consisted of 150 mg of fostamatinib or a placebo administered orally twice daily for 14 days. The primary outcome was the number of oxygen-free days within 28 days, an ordinal metric considering mortality and oxygen dependency. Secondary outcomes included 28-day all-cause mortality, respiratory failure-free survival, and clinical status using the World Health Organization (WHO) ordinal scale.
The primary outcome revealed no statistically significant difference in oxygen-free days between the fostamatinib group (mean = 13.4 days, standard deviation [SD] = 12.4) and the placebo group (mean = 14.2 days, SD = 12.1; adjusted odds ratio [OR] = 0.82, 95% credible interval [CrI] = 0.58–1.17). Mortality at 28 days occurred in 11.3% of the participants receiving fostamatinib compared with 8.1% in the placebo group (adjusted OR = 1.44, 95% CrI = 0.72–2.90). The secondary outcomes, including respiratory failure-free survival and WHO clinical progression scale, also showed no statistically significant differences between the groups.
Safety analyses identified elevated aspartate aminotransferase levels in 11.6% of the fostamatinib group vs 5.5% in the placebo group (adjusted OR = 2.28, 95% CrI = 1.07–4.84). Other adverse events, including hypertension and neutropenia, were comparable between the groups.
The findings showed that fostamatinib was not associated with a significant improvement in oxygen-free days or a reduction in mortality in hospitalized patients with COVID-19 infections. These results did not support fostamatinib’s effectiveness in improving outcomes in this patient population during the Omicron era. The researchers suggested that further research is needed to explore its potential efficacy in specific subgroups.
Full disclosures can be found in the published study.
