AstraZeneca ($AZN) has launched a Phase III test of its targeted IL-13 asthma drug tralokinumab, beefing up its late-stage pipeline for respiratory diseases and squaring off against some major league competition now in the clinic.

The antibody, which targets a cytokine that is believed to play a big role in spurring severe asthma, emerged from AstraZeneca’s U.S. subsidiary MedImmune. It’s also currently in a mid-stage study for idiopathic pulmonary fibrosis.

But AstraZeneca faces some heavyweight competition in the clinic. Back in March Roche ($RHHBY) heralded upbeat Phase IIb data for its IL-13 antibody lebrikizumab, which CEO Severin Schwan picked back in 2011 as one of three big prospective blockbusters in the pipeline. That drug is headed for a 2016 rendezvous with regulators. Receptos ($RCPT), meanwhile, in-licensed an IL-13 drug from AbbVie ($ABBV) after the pharma company decided to de-prioritize its respiratory efforts, including a program for asthma. Receptos is testing RPC4046 for Eosinophilic esophagitis, an orphan disease, and AbbVie has an option to buy it back.