Merck paid $230m upfront for two clinical-stage DNA damage and repair candidates and two additional preclinical programs, of which the company will take full responsibility in development and commercialization.
US-based Vertex will also receive royalties on future net sales.
The acquired ataxia telangiectasia and Rad3-related (ATR) protein kinase inhibitor program includes two clinical-stage compounds, VX-970 and VX-803.
VX-970 is being assessed in several phase I and phase II studies across a range of tumor types in biomarker-defined patient groups.
VX-803 is an oral ATR inhibitor undergoing phase I dose-escalation studies both as monotherapy and in combination with chemotherapy.
The DNA-dependent protein kinase (DNA-PK) inhibitor program includes VX-984, which is in Phase I dose-escalation trials alone and combined with pegylated liposomal doxorubicin, against advanced solid tumors.
Merck will combine the assets with its existing DNA-PK assets into a single development program.
Merck Healthcare CEO and member of the executive board Belen Garijo said: "With this strategic deal, we significantly strengthen our oncology pipeline in two attractive areas where we have leading competence, DNA damage and repair and immuno-oncology – areas which also have promising therapeutic synergy."
Vertex chairman, president and CEO Jeffrey Leiden said: "The Vertex R&D team has produced a portfolio of first-in-class compounds with the potential to enhance the therapy of multiple cancers.
"We are pleased to partner with Merck, a leader in oncology with exciting complementary assets that will help fully realize the value of these unique compounds and accelerate the programs' potential benefits for patients."