Sanofi and Regeneron have put their experimental antibody dupilumab into a Phase III trial assessing its potential in uncontrolled persistent asthma, which the firms hope will serve as one of the pivotal efficacy studies required for a US submission.

The global, placebo-controlled Phase III study is looking to enrol more than 1,600 patients to evaluate two doses of dupilumab - 200 milligrams and 300 mg - subcutaneously administered every other week.

The news came alongside the release of more data from a Phase II trial evaluating the drug’s effect in adult patients with moderate-to-severe uncontrolled asthma, which the companies believe US regulators will accept as the first required pivotal efficacy study necessary for the proposed indication.

As previously reported, this study hit its primary goal of showing an improvement in lung function in asthma patients with high blood eosinophils counts, which are thought to be a marker for those more likely to have atopic or allergic asthma. But new data on secondary endpoints also show positive results for patients with low blood eosinophils, who are thought to be less likely to suffer from allergic asthma and thus less likely to this type of therapy.

In this population, patients given either dose of dupilumab showed an approximate 8% improvement in lung function (as measured by forced expiratory volume over one second) at Week 12 compared to placebo, both in combination with ICS/LABA treatment.  Also, the dupilumab-based regimen showed 68% and 62% reductions, respectively, in adjusted annualised rate of severe exacerbations versus the control arm, the firms said.

Dupilumab, which targets interleukin-4 and interleukin-13, proteins believed to play a part in the inflammatory process, is already being tested in Phase III for eczema.