Merck to acquire biotech company Prometheus Biosciences for $10.8bn

Merck has agreed to acquire Prometheus Biosciences, a Nasdaq-listed clinical-stage biotechnology company, in an all-cash deal worth around $10.8 billion, in a move to bolster its immunology pipeline.

The California-based Prometheus Biosciences is engaged in the discovery, development, and commercialization of therapeutic and companion diagnostic products for the treatment of immune-mediated diseases by using a precision medicine approach.

As per the terms of the deal, its shareholders will be paid $200 per share by Merck.

Prometheus Biosciences’ lead candidate is PRA023, which is a humanized monoclonal antibody (mAb). PRA023 targets tumor necrosis factor (TNF)-like ligand 1A (TL1A), which is a target related to intestinal inflammation as well as fibrosis.

PRA023 will be developed to aid in the treatment of diseases mediated by the immune system such as ulcerative colitis (UC) as well as Crohn’s Disease (CD) and various immune-mediated conditions.

Robert M. Davis — Merck chairman and CEO said: “At Merck, we are committed to delivering on our purpose to save and improve lives and continue to identify and secure opportunities where compelling science and value creation align.

“The agreement with Prometheus will accelerate our growing presence in immunology where there remains substantial unmet patient need. This transaction adds diversity to our overall portfolio and is an important building block as we strengthen the sustainable innovation engine that will drive our growth well into the next decade.”

Merck to acquire biotech company Prometheus Biosciences for $10.8bn. Photo courtesy of Merck & Co., Inc.

Last December, Prometheus Biosciences announced positive data for PRA023 from the ARTEMIS-UC phase 2 trial. The placebo-controlled study assessed the safety and efficacy of the humanized monoclonal antibody in patients suffering from moderate to extremely active ulcerative colitis.

Prometheus Biosciences also registered positive results from the APOLLO-CD phase 2A open-label study that tested PRA023’s safety and effectiveness in patients suffering from moderate or severe Crohn’s Disease.

Mark McKenna — Prometheus Biosciences chairman and CEO said: “Prometheus was established to revolutionize the treatment of immune-mediated diseases through the application of a powerful precision medicine approach.

“This agreement with Merck, a leader in biopharmaceutical research and development, allows Prometheus to maximize the potential for PRA023, while continuing to apply our technology and expertise to fuel further discoveries to address the needs of patients with immune disorders.”

The deal, which is likely to close in Q3 2023, is subject to Prometheus Biosciences’ shareholder approval and certain other conditions.

In late 2022, Merck signed a deal worth around $1.35 billion to acquire Imago BioSciences with an aim to expand its blood disorder drugs portfolio.