GSK antibody falls short in hospitalized Covid-19 patients, but may help elderly
An experimental GlaxoSmithKline drug in testing for hospitalized Covid-19 patients failed to distance itself from standard treatment in a mid-stage clinical trial, but the pharmaceutical giant plans to continue testing the drug based on data suggesting the elderly might respond better to the treatment.
The main goal of the Phase 2 study was to show the proportion of Covid-19 patients alive and free of respiratory failure after 28 days of treatment with the drug, otilimab, compared to treatment with the standard of care alone. Patients in the otilimab group received that intravenously infused drug alongside standard of care treatments, which included antiviral drugs and steroids.
GSK said Thursday that the data in patients of all ages showed improvement in the treatment group, but not enough to be statistically significant. Nonetheless, the pharma giant pointed to better results in the group of patients 70 and older. In a pre-planned analysis, GSK reported that 65.1% of the 180 patients in this subgroup who received the study drug were still alive and free of respiratory failure after 28 days, compared to 45.9% of those in the subgroup that received the standard of care alone.
Results for the subgroup also looked better in a mortality analysis. After 60 days, GSK reported that 40.4% of those who received only the standard of care had died compared to 26% of those given the study drug.
In light of those results, GSK has decided to continue the clinical trial by testing a new group of patients 70 and older. The company said this additional group will follow a similar clinical trial design and will enroll about 350 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,” Christopher Corsico, senior vice president of development at GSK, said in a prepared statement.
GSK’s otilimab is an antibody designed to block granulocyte-macrophage colony-stimulating factor (GM-CSF), a protein that plays key role multiple immune-mediated diseases. GSK licensed rights to otilimab from MorphoSys in 2013. The drug is not yet approved in any indication; the pharmaceutical giant had advanced it to Phase 3 testing in rheumatoid arthritis.
The Phase 2 study in Covid-19 enrolled 806 patients, ranging in age from 18 to 79, who were hospitalized with severe pulmonary disease related to Covid-19 infection. The clinical trial spanned 130 sites around the world. Respiratory failure was the most serious adverse event reported in the study, observed in 5% of those given the standard of care and 4% of those in those treated with otilimab.
GSK said that all adverse events and serious problems observed in the study were typical of Covid-19 infection. But the company added that in the 70 and older subgroup, the rates of these serious problems and fatalities were lower in those who received the study drug compared with those who received standard care.
A full analysis of the study results is underway. GSK said results will be released in an upcoming pre-print publication when available.
GSK is approaching Covid-19 on multiple fronts. The company’s adjuvant is included with experimental vaccines in development from Medicago and Sanofi. GSK is also partnered with CureVac on the German company’s messenger RNA vaccine. In addition to those alliances, GSK is partnered with Vir Biotechnology, developing the San Francisco-based biotech’s experimental antibodies for treating and preventing infection from the novel coronavirus. Last week, GSK and Vir expanded that alliance to include influenza and other respiratory viruses.