Merck KGaA pens pact, eyes checkpoint inhibitor combos

Merck KGaA has struck a deal for assets it can pair with immune checkpoint inhibitors. The deal sees Merck commit to €240 million ($258 million) in milestones to bag Domain Therapeutics’ next-generation adenosine receptor program.

Domain will work with Merck to apply its G protein coupled receptor (GPCR) capabilities to the development and testing of drugs targeting adenosine receptors. Merck’s interest in the targets is underpinned by research showing that antagonizing certain adenosine receptors slows tumor growth. Domain thinks this makes the antagonists promising partners for checkpoint inhibitors—and Merck is convinced enough in the potential to open its wallet.

“This new generation of adenosine receptor antagonists is an important addition to our immuno-oncology pipeline,” Laszlo Radvanyi, head of immuno-oncology research at Merck, said in a statement. “We plan to explore the promise of adenosine receptor antagonists and develop novel compounds to potentially use in new combination immunotherapies for cancer.”

Merck will support the research program and pick up the worldwide rights to any assets resulting from the collaboration. In return, the German life science company has committed to paying €240 million or more in milestones and royalties.

The early-stage, back-loaded nature of the deal means Domain may ultimately receive far, far less than that amount. But, whatever the final financial reward, the agreement will enable Domain to apply its GPCR capabilities to new targets and give it a partner with a growing presence in the field of immuno-oncology. Domain, a French biotech, has retained two in-house, early-stage oncology programs.

Work on the Merck program is still in drug discovery. If assets from the program advance, they will join an increasingly well -stocked clinical immuno-oncology pipeline. Earlier this month, Merck paid Vertex Pharmaceuticals $230 million for the rights to four cancer programs. These assets now sit alongside the German drugmaker’s own candidates, such as PD-L1-TGFβ bifunctional immunotherapy M7824.

In turning to Domain for help opening its next front in immuno-oncology R&D, Merck has returned to an old collaborator. Merck and Domain previously teamed up in 2011 to develop metabotropic glutamate receptor 4 positive allosteric modulator drugs targeting diseases including Parkinson’s. That deal fell foul of a reshuffle at Merck, although the program lives on at Serono spinout Prexton Therapeutics.

Novartis has also shown an interest in adenosine receptor antagonists. The Swiss drugmaker picked up the rights to a phase 1 program in 2015 through a deal with Spain’s Palobiofarma.