News Release

Merus Announces Issuance of Three U.S. Patents Strengthening its Biclonics® Technology Platform for the Discovery and Manufacturing of Human Bispecific Antibodies

March 9, 2016 at 9:00 AM EST

Utrecht, The Netherlands, March 9, 2016 - Merus B.V., a clinical-stage immuno-oncology company developing innovative bispecific antibody therapeutics, announced today that the United States Patent and Trademark Office (USPTO) has issued three patents related to the generation of bispecific antibodies and to high-throughput functional screening methods of large collections of bispecific antibodies.

The patents include claims covering the efficient formation of bispecific antibodies in individual cells, which supports the Company's industry-scale manufacturing using the standard processes that are also used for the production of conventional monoclonal antibodies. Furthermore, the issued patents cover methods used by Merus to identify lead candidates with multiple mechanisms of action that have the potential to effectively kill tumor cells with high potency. This is an important step in the identification of lead bispecific antibody candidates with functionalities that compare favorably against other forms of immunotherapeutics, such as conventional monoclonal antibodies as well as their combinations. The issued patents include U.S. Patent No. 9,145,588, U.S. Patent No. 9,248,181 and U.S. Patent No. 9,248,182 and are expected to expire no earlier than between 2032 and 2033.

"These patents expand and strengthen our intellectual property portfolio and further reinforce our unique position in the bispecific antibody space," said Ton Logtenberg, Ph.D., Chief Executive Officer of Merus. "Our Biclonics® technology platform, which retains the Immunoglobulin G format of conventional monoclonal antibodies, is the discovery engine for our pipeline of bispecific antibody candidates. The patents cover both our methods for the discovery of lead bispecific antibody candidates in cell-based functional assays as well as our clinical and commercial scale production. We continue to methodically and strategically expand our intellectual property estate around this technology platform as well as around our growing portfolio of immuno-oncology therapeutic candidates."

About Merus B.V.
Merus is a clinical-stage immuno-oncology company developing innovative bispecific antibody therapeutics, referred to as Biclonics. Biclonics are based on the full-length IgG format, are manufactured using industry standard processes and have been observed in preclinical studies to have several of the same features of conventional monoclonal antibodies, such as long half-life and low immunogenicity. Merus' lead bispecific antibody candidate, MCLA-128, is being evaluated in a Phase 1/2 clinical trial in Europe as a potential treatment for HER2-expressing solid tumors. Merus' second bispecific antibody candidate, MCLA-117, is being developed as a potential treatment for acute myeloid leukemia. The Company also has a pipeline of proprietary bispecific antibody candidates in preclinical development, including Biclonics designed to bind to various combinations of immunomodulatory molecules, including PD-1 and PD-L1.

Contacts:
Merus B.V.
Shelley Margetson - s.margetson@merus.nl
+31 (0)30 253 8800

Argot Partners
Eliza Schleifstein - eliza@argotpartners.com
1-917-763-8106