GlaxoSmithKline (GSK) has decided to amend a Covid-19 study that seeks to determine the effectiveness of a fully human monoclonal antibody, Otilimab, in treating hospitalised adult patients with Covid-19.

The move comes after the Phase II proof of concept Otilimab in Severe COVID-19 Related Disease (OSCAR) study demonstrated significant effectiveness on older patients.

The primary objective of the study is to identify the proportion of Covid-19 patients alive and free of respiratory failure 28 days after administering a single dose of otilimab in addition to standard of care (including anti-viral treatments and corticosteroids), compared to placebo.

It is a multi-centre study and enrolled 806 adults (aged 18 to 79 years) with severe Covid-19 related pulmonary disease, hospitalised at 130 sites around the world.

Analysis of the data shows a statistically insignificant difference of 5.3% when the data from patients of all ages was assessed.

However, a pre-planned efficacy analysis by age in patients aged 70 or more showed that 65.1% of patients were alive without respiratory failure after 28 days of administering otilimab.

Additionally, a mortality analysis up to day 60 for the same age group also favoured otilimab over placebo.

With the data indicating a potential clinical benefit for older high-risk patients, GSK will amend the OSCAR study to expand this cohort to confirm the findings.

In the revised study, GSK plans to enrol around 350 patients aged 70 years and older.

GSK Development senior vice-president Christopher Corsico said: “Patients aged 70 and over account for 70% of Covid-related deaths and nearly 40% of hospitalisations.

“Our scientific understanding of Covid continues to evolve at a rapid pace with recent studies suggesting that GM-CSF is elevated in this group of patients.

“Given the profound impact this pandemic is having on the elderly and the encouraging data we are sharing today, we are hopeful this finding will be replicated in the additional cohort.”

GSK recently commenced the dosing of patients in Phase III clinical programme of its Respiratory Syncytial Virus (RSV) candidate vaccine for older adults.