GSK announced Thursday that it has reached a $66 million exclusive license agreement for Spero Therapeutics’ late-stage antibiotic asset, Tebipenem HBr.

As part of the deal, GSK will pay Spero $66 million upfront with the potential for future milestones and tiered royalties. The British pharma giant will also acquire 9% of Spero stock.

GSK will have the exclusive license to commercialize Tebipenem, an oral antibiotic for urinary tract infections, in all territories except Japan and Asia. 

Tebipenem’s track record in 2022 has been a rocky one.

In May, the Food and Drug Administration indicated there were issues with Spero’s Tebipenem application, conducting a separate analysis of the microbiological intent-to-treat population. The company subsequently laid off 75% of its workforce, including two top executives. The next month, the FDA rejected Tebipenem’s application.

Spero said it expects to start a new phase 3 clinical trial for Tebipenem next year, adding that it has received “encouraging US FDA regulatory feedback on the proposed clinical trial design.”

Despite the starts and stops with the embattled drug, GSK is betting on a rebound. 

GSK Chief Commercial Officer Luke Miels said that Tebipenem has a “clear US FDA regulatory path to potential approval” that could help patients with complicated cases of UTIs.

“There is a high unmet medical need for a novel oral antibiotic as an alternative to intravenous hospital therapy for drug-resistant complicated urinary tract infections,” Miels said in a statement. “Tebipenem HBr complements GSK’s infectious disease strategy and is consistent with our commitment to find value-enhancing opportunities to build a strong late-stage portfolio.”