Benralizumab jabs prevented severe flare-ups of asthma which could no longer be controlled with high dose steroid inhalers and other drugs.
The drug targets and clears away rogue immune cells in the lungs called eosinophils that play a key role in allergies and asthma.
Two trials, Calima and Sirocco, compared the effects of benralizumab and a dummy placebo treatment in more than 2,500 patients with severe asthma.
Both found that the drug significantly reduced rates of ‘exacerbations’ – episodes of progressively-worsening shortness of breath, wheezing, and chest tightness.
In the Calima trial exacerbations were cut by 28-36 per cent. The Sirocco trial saw a 45-51 per cent reduction.
Professor Eugene Bleecker, from the Wake Forest School of Medicine, in Winston-Salem, US, who let the Sirocco trial, said:
Patients with severe, uncontrolled asthma have very few treatment options once they are already taking high-dose inhaled corticosteroids and long-acting beta agonists.
Our studies show that eosinophil counts were nearly completely depleted by week four of treatment.
Calima trial leader Professor Mark FitzGerald from the University of British Columbia, Canada, said: ‘The results from both trials indicate that benralizumab treatment once every four or eight weeks decreased eosinophil counts, reduced asthma exacerbations, and improved lung function for patients with severe, uncontrolled asthma with eosinophilia.’
The findings are published in The Lancet medical journal and were presented at the European Respiratory Society’s annual meeting in London.