Agenus Inc. closed an offering of 18,459 convertible preferred shares to certain institutional investors at $2,167 apiece to raise about $40 million in gross proceeds.

Holders can convert each share into 1,000 common stocks at an initial conversion price of $2.167 per common share.

The Lexington, Mass.-based company expects to use the amounts raised for working capital purposes.

Agenus focuses on the development of cancer treatments that engage the body's immune system to fight disease.