Trius targets key approvals after antibiotic matches Zyvox (again) in Phase III

Trius Therapeutics has trumpeted more success from a pivotal program for a next-gen antibiotic against acute infections such as superbugs. After reporting Monday that its tedizolid phosphate met key objectives in a Phase III trial, the San Diego-based developer ($TSRX) plans to file for approvals of the new antibiotic in the U.S. and the European Union in the second half of 2013.

Tedizolid, or TR-701, is hugely important to Trius, which has no other products in its pipeline that are nearly as close to reaching the market. To the rest of world, the next-gen antibiotic offers a potential antibacterial weapon amid the growing threat of drug-resistant bugs that render old warhorse antibiotics ineffective. Many big drugmakers have fled from antibiotics development because of financial challenges in the field, presenting a potential opportunity to Trius and other small biotechs to answer the call for new drugs.

In the company's Phase III trial called Establish 2, Trius managed to maintain the promising profile of tedizolid as a new alternative to Pfizer's ($PFE) blockbuster antibiotic Zyvox for patients with acute bacterial skin and skin structure infections, following upbeat results from a previous late-stage study called Establish 1. The latest top-line data show that an IV version of tedizolid was noninferior to Zyvox, meeting the primary goal of the Phase III trial. And the study hit all secondary goals as well, the company reported.

Trius has touted the potential economic benefits of once-daily dosing of tedizolid versus twice-daily treatment with Zyvox (linezolid) for 10 days. Zyvox has been a top seller with 2011 revenue of $1.3 billion, but Pfizer's antibiotic is expected to face patent expiration in 2015, according to Leerink Swann analysts in a note to investors in December. If tedizolid is approved, Trius could quickly encounter competition from low-cost generic linezolid.

On today's news of a Phase III win, Trius' shares were down 2.4% to $6.82 as of 11:18 a.m. EST.

"The consistently strong results of the two Phase 3 studies support the promise of tedizolid as a safe and effective new antibiotic, especially in an era of increasing multi-drug resistant Staphylococcus aureus," Dr. Andrew F. Shorr, associate professor of medicine at Washington Hospital Center, stated in Trius's release. "The potential to treat severe MRSA infections with a novel once-daily agent and a shorter course of therapy offers substantial benefits to patients and, potentially, payers and the healthcare system."

Bayer has partnered with Trius on the lead antibiotic for Japan as well as emerging markets in Asia, Africa, South America and the Middle East.

- here's Trius' release