Rigel Pharmaceuticals has reported that the Phase II clinical trial of its oral spleen tyrosine kinase (SYK) inhibitor fostamatinib in treating hospitalised Covid-19 patients met the primary endpoint of safety.

Being carried out in partnership with the National Institutes of Health (NIH) unit National Heart, Lung, and Blood Institute (NHLBI) and Inova Health System, the double-blind, placebo-controlled, multi-centre trial analysed the safety of fostamatinib in treating hospitalised Covid-19 patients.

The study enrolled 59 subjects who needed supplemental oxygen via nasal canula or non-invasive ventilation, mechanical ventilation, or extracorporeal membrane oxygenation.

They were randomised into a 1:1 ratio to receive an oral twice-daily dose of fostamatinib plus standard of care (SOC) or matching placebo plus SOC for 14 days. They were also followed for 60 days.

Results showed that fostamatinib halved the chances of occurrence of serious adverse events.

No deaths were reported in the fostamatinib cohort versus three deaths observed in the placebo arm.

The trial had a total of four intubated patients on mechanical ventilation. Data showed that the two patients receiving fostamatinib improved in seven days and were off the ventilator, while two others in the placebo group succumbed to death.

Fostamatinib was superior to placebo in expediting improvement in clinical status by day 15 and 29. The number of days in the ICU was three days in the fostamatinib group versus seven in the placebo group.

Rigel Pharmaceuticals president and CEO Raul Rodriguez said: “We are extremely pleased with the outcome of this trial, which provides early indications of the potential positive impact of fostamatinib for patients with Covid-19.

“These results are an important addition to the extensive accumulation of data evaluating fostamatinib in Covid-19, which also include the ongoing Phase II study with Imperial College London and our own Phase III clinical trial being conducted in the US and Latin America.”

The company intends to hold talks with the US Food and Drug Administration on the potential for emergency use authorisation of fostamatinib for treating hospitalised Covid-19 patients.

Separately, PREXA SANTÉ has announced positive top-line results from a human clinical trial of its combination medical device/drug treatment for Covid-19, Product-118.

Preliminary data indicated that Product-118 was highly effective as a Covid-19 treatment after just a few days of once-daily doses. No side effects were reported.