Spero Therapeutics Shares Take Flight Premarket on GSK Pact

By Colin Kellaher

Shares of Spero Therapeutics Inc. nearly doubled in premarket trading Thursday after the clinical-stage biopharmaceutical company agreed to license tebipenem HBr, its late-stage antibiotic asset, to U.K. pharma major GSK PLC in a deal potentially worth hundreds of millions of dollars to Spero.

Under the agreement, Spero will receive an upfront payment of $66 million from GSK, which also will invest $9 million to buy 7.45 million Spero shares at around $1.21 apiece, a 47% premium to Wednesday's closing price of about 82.2 cents for the Cambridge, Mass., company.

Spero said it is also eligible for up to $525 million in future milestone payments, along with royalties on sales.

Spero shares were recently up 92% to $1.58 in premarket trading Thursday.

Write to Colin Kellaher at [e-mail]

(END) Dow Jones Newswires

09-22-22 0615ET