Partner Therapeutics has reported positive top-line results from the investigator-led study of inhaled Leukine (sargramostim) in hospitalised Covid-19 patients.

A yeast-derived recombinant human granulocyte-macrophage colony stimulating factor (rhuGM-CSF), Leukine is approved by the FDA.

Named SARPAC (Sargramostim in Patients with Acute Hypoxic Respiratory Failure and Acute Covid-19), the prospective, randomised, open-label study was led by University Hospital Ghent, Belgium and was carried out at five Belgian hospitals.

It used inhaled sargramostim to target the lungs on 81 Covid-19 patients with acute hypoxic respiratory failure needing supplemental oxygen.

Data showed that five days of inhaled sargramostim plus standard of care (SOC) treatment improved oxygenation in patients, thereby meeting the primary endpoint.

An improvement in oxygenation in at least 33% or more from baseline was observed in 54% of patients receiving sargramostim plus SOC cohort versus 26% in the SOC cohort.
Inhaled sargramostim was also shown to be well tolerated, with similar adverse events across both cohorts.

Sargramostim-treated subjects had a statistically significant increase in CD8-positive anti-viral T-cell activation specifically recognising the Covid-19 virus in translational research.

Partner Therapeutics chief technology officer Dr Debasish Roychowdhury said: “PTx is heartened that this study shows Leukine’s potential to help patients in the midst of this pandemic.

“We are deeply grateful for the work being done by the clinical research teams in Belgium and for the patients who have participated in the SARPAC trial.”

Apart from the SARPAC study, inhaled sargramostim is being analysed in the iLeukPulm study at 11 sites in the US. It enrolled 120 patients randomised in a 2:1 ratio to receive sargramostim plus SOC or SOC alone.

The study is evaluating inhaled sargramostim’s ability to improve oxygenation in hospitalised Covid-19 patients. Enrolment has been completed and the results are anticipated in the second quarter of this year.

Partner Therapeutics is also introducing the SCOPE trial to analyse sargramostim in 400 Covid-19 patients in an outpatient setting.