MALVERN, Pennsylvania (

TheStreet

) -- Shares of

Orthovita

(VITA)

rose more than 40% after agreeing to be acquired by competitor

Stryker

(SYK) - Get Report

for $3.85 a share, or about $318 million.

Orthovita shares rose 40.1%, or $1.10, to $3.83 in early afternoon trading Monday.

Stryker's offer is a 41% premium from Orthovita's closing price Friday.

Orthovita, with annual revenue of about $95 million, makes Vitoss bone grafts and Cortoss bone augmentation material, and also sells Vitagel, a product designed to reduce bleeding.

Stryker shares rose 1.1% to $63.99.

-- Written by Joseph Woelfel

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Joseph Woelfel

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