Spero’s late-stage active, tepenem HBr, is being developed as the first oral carbapenem antibiotic to treat urinary tract infections, including pyelonephritis, that are caused by specific bacteria.
Under the deal, GSK will receive an exclusive license to develop and market tepenem pivoxil HBr in all countries. This license will exclude Japan and some Asian countries, which will be retained by Spero’s partner Meiji Seika Pharma.
Since 2009, Meiji has been marketing teppenem HBr in Japan. Known as Orapenem, it is marketed to treat pediatric infections limited to pneumonia, otitis media and sinusitis.
Under the new agreement, Spero will receive an upfront payment of $66 million from GSK for the initial rights to the treatment.
GSK will also make potential milestone payments and differentiated royalty payments in the future.
Spero will handle the implementation and costs associated with the phase III trial of lead HBr.
After receiving encouraging regulatory feedback from the US Food and Drug Administration (FDA) on the proposed trial design, the company intends to initiate the Phase III trial next year.
In addition, GSK will oversee the performance and costs associated with further clinical development, including submissions to regulatory agencies and marketing activities of the antibiotic in applicable countries.
As part of the license agreement, GSK will purchase $9 million worth of shares of Spero common stock under a stock purchase agreement between the companies.
Subject to the necessary closing conditions, the transactions are expected to close in the fourth quarter of the year.
GSK Chief Commercial Officer Luke Miels said: “Tebipenem HBr complements GSK’s infectious diseases strategy and aligns with our commitment to find value-enhancing opportunities to build a strong late-stage portfolio.
“Tebipenem HBr has a clear US FDA regulatory pathway for potential approval that could be of significant benefit to patients with complicated urinary tract infections.”
In July, GSK acquired Sierra Oncology for $1.9 billion in cash.