Tailored immune therapy passes safety test for COVID-19, advances to larger efficacy trials

The NIH Clinical Center is shown during the winter while snow blankets the ground.
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As researchers study how to prevent COVID-19, they continue to evaluate ways to support patients with severe illness. Medical researchers recently found – in a phase 2 study looking at safety –  that among 59 hospitalized patients who required breathing assistance, those who received fostamatinib, a tailored immune therapy used to treat adults with chronic immune thrombocytopenia, a rare bleeding disorder, did not have more severe outcomes compared to those receiving a placebo. The findings appear in the journal Clinical Infectious Diseases 

The NHLBI-sponsored, double-blinded, randomized, controlled trial took place at the NIH Clinical Center and at Inova Fairfax Hospital in Virginia. Each patient received fostamatinib or a placebo for 14 days in conjunction with the best standard of care, including the antiviral remdesivir and steroids. The researchers assessed adverse events, including extreme blood clotting and organ failure, among patients in each group for 28 days. They noted other signs of disease progression, such as clinical markers of inflammation, and signs of recovery, including breathing independently or leaving the hospital. “We are encouraged to see that for COVID-19 patients requiring hospitalization, fostamatinib in combination with the best standard of care was shown to be well tolerated,” said Richard Childs, M.D., the clinical director of the NHLBI. “Patients treated with fostamatinib not only had less severe adverse events, but were observed to have improved clinical outcomes compared to those receiving placebo and the best standard of care.”  

Jeffrey Strich, M.D., a principal investigator of the study and a physician at the NIH Clinical Center, agreed, adding: “Additional studies are needed to confirm the efficacy findings and show how fostamatinib may regulate the exuberant COVID-19 immune responses in patients.”  

Two phase 3 trials, including one supported by NHLBI and another by Rigel Pharmaceuticals, Inc., the developer of fostamatinib, will assess how hundreds of patients hospitalized for COVID-19 respond to the treatment.