Does Roche's IL-13 setback in PhIII signal similar trouble ahead for AstraZeneca?

Trouble with Roche's late-stage IL-13 asthma drug lebrikizumab raises questions about just how effective this R&D strategy will be for the crowded field of players in severe asthma. More specifically, Roche's troubles may foreshadow issues ahead for AstraZeneca's tralokinumab, another IL-13 player that's faced setbacks in the clinic.

Yesterday, Roche ($RHHBY) noted that it had recorded a split decision on two Phase III studies for lebrikizumab, with one success and one flop in reducing the rate of severe exacerbations for patients with severe asthma. The studies were identical, with both focused on the same biomarkers that could be used to identify the right patient population.

AstraZeneca's ($AZN) tralokinumab has already failed a Phase IIb study for asthma. Investigators reported last summer that the drug failed to reduce exacerbations in a study that recruited 452 patients in 98 sites. They did track an improvement in lung function, though, with a once-every-two-week dose (though not at four weeks). And that was all being followed up now in Phase III.

A spokesperson for AstraZeneca says that the company decided to get rid of its program for testing tralokinumab in idiopathic pulmonary fibrosis, noting the deletion in its annual pipeline summary in early February. But there's still a strong belief at the pharma giant that tralokinumab will work for asthma.

"Interim analysis of a Phase II study in subjects with mild to moderate IPF showed no safety issues, but a lack of efficacy on clinical end points of IPF progression," noted the spokesperson. "The analysis met pre-specified criteria for futility and dosing of study drug was stopped. The underlying biological drivers of IPF are incompletely understood but this result suggests that IL-13 is not a key mediator of disease progression in this population.

AstraZeneca CEO Pascal Soriot

"It is well accepted that the disease pathophysiology underlying IPF is both complex and very different to that of asthma and AD (atopic dermatitis). IL-13 is a key Th2 cytokine implicated in both asthma and AD and we are committed to the ongoing program of studies."

AstraZeneca CEO Pascal Soriot has been making the case that he has the kind of pipeline that can deliver the dramatic increases in revenue that he's been promising investors since Pfizer ($PFE) came calling with an unwelcome takeover offer. But the quest leaves little margin for error. -- John Carroll (email | Twitter)