Agenus Inc. is a Lexington, Massachusetts-based biotechnology company focused on immunotherapy including immuno-oncology, a field that uses the immune system to control or cure cancer.

In February 2014 the company acquired a European firm, 4-Antibody, along with their portfolio of checkpoint modulators (CPMs) and a platform (Retrocyte Display® technology) to rapidly and efficiently discover new antibodies.

In October 2013, Agenus CEO Garo Armen issued a press release revealing that after an 18-month follow up on the RTS,S Malaria vaccine using QS21-Stimulon®, it was working well enough to support a regulatory filing in 2014.

Under the terms of that deal, Agenus is using its proprietary Retrocyte Display technology to discover antibodies against a pair of undisclosed checkpoint targets for the treatment of cancer.

The deal involves the discovery and development of therapeutic antibodies to two undisclosed Merck checkpoint targets, both thought to be relevant for cancer treatment.

4-Antibody: February 2014, Agenus acquired European biotechnology firm 4-Antibody, along with its Retrocyte Display technology and a portfolio of checkpoint modulator antibody candidates .

The leader of the Ludwig collaborative laboratory at Memorial Sloan Kettering Cancer Center, Jedd Wolchok, is recognized as one of immuno-oncology's leading pioneers.

Agenus is the sole US-manufacturer of a patented and FDA-approved triterpene glycoside extract known as (QS-21, Matrix M), which is a key component in the manufacturing of the Oxford–AstraZeneca COVID-19 as well as the Novavax COVID-19 vaccines.