Merck inks $773M Tilos takeout to bag TGFβ cancer programs

Merck has struck a $773 million detail to buy Tilos Therapeutics. The takeover will give Merck control of a pipeline of cancer, fibrosis and autoimmune programs targeting the latent TGFβ complex.

Since setting up shop in 2016, Massachusetts-based Tilos has used money from Boehringer Ingelheim Venture Fund and Partners Innovation Fund to develop anti-LAP antibodies based on advances made by Galina Gabriely and Howard Weiner at Brigham and Women’s Hospital. 

The focus on LAP stems from evidence that the peptide holds TGFβ, a cytokine, in an inactive form. By targeting LAP, Tilos hopes to reduce TGFβ activity. That idea caught the attention of Merck.

“Tilos has developed a compelling portfolio of candidates that employ a novel approach to modulating the potent signaling molecule TGFβ by binding to latency-associated peptide, with potential applications across a range of disease indications,” Merck Senior Vice President Dean Li said in a statement. 

Tilos has focused its attention on the applications of the approach to cancer, although it also has early efforts underway in fibrosis and autoimmune disease. Neither of the companies has shared a good look at their plans for the preclinical programs, but Tilos has posted examples of how anti-LAP antibodies can work to treat disease.

Some of the anti-LAP antibodies created by Tilos are designed to deplete immunosuppressive cells and inhibit the release of TGFβ, without affecting LAB-TGFβ complexes in the extracellular matrix. In doing so, Tilos thinks it can safely inhibit pathological and immuno-regulatory processes.

Another example shared by Tilos discusses anti-LAP antibodies that preferentially bind to LAP+ myeloid-derived suppressor cells (MDSC) over LAP+ regulatory T cells. By depleting inhibitory cells, Tilos thinks it can increase antitumor activity in cancers dominated by MDSC.

Gaining the ability to manipulate the tumor microenvironment in such ways is a priority for Merck and its rivals, which are seeking drugs that make their existing immuno-oncology assets more broadly effective. 

Merck could ultimately pay $773 million to buy Tilos but hasn't disclosed what it is paying upfront.