Merck Biologics

Merck & Co. is pushing deeper into biopharmaceuticals with the purchase of two biotechnology companies that enhance its ability to discover, develop, and manufacture protein-based drugs and vaccines.

Merck will pay $400 million for Lebanon, N.H.-based GlycoFi, which has genetically modified yeast to enable the production of therapeutic proteins with human sugar structures. Currently marketed monoclonal antibodies are grown in mammalian cell culture, a medium in which it is sometimes prohibitively expensive to achieve complex protein glycosylation.

The GlycoFi system has not been proven on a commercial scale, says Tom Ransohoff, a senior consultant with BioProcess Technology Consultants, but it has the potential to address several challenges of mammalian cell culture production. He notes that yeast grows quickly and presents fewer concerns about viral contamination. Most important, yeast generates a homogenous glycoform, a glycoprotein with sugars attached, rather than the heterogenous mixture of glycoforms produced in mammalian cell culture.

GlycoFi's glycoengineering technology complements Merck's in-house yeast expression system. Merck says the technology combination could help accelerate the discovery and development of both vaccines and protein-based oncology drugs. Although Merck has a growing portfolio of vaccines, it has less experience in bringing monoclonal antibodies to market.

Merck will lay out another $80 million for Santa Clara, Calif.-based Abmaxis, which is focused on discovering and optimizing monoclonal antibodies. Abmaxis starts with either an antigen target or an antibody and then designs a structure-based antibody library from which drug candidates are selected.

Merck took both companies' technologies for test drives before making the purchases. The pharmaceutical giant signed up last December to use GlycoFi's platform to develop biologic and vaccine drug candidates, and in late 2004 it enlisted the help of Abmaxis to reengineer one of its human monoclonal antibodies.