Swiss drugmaker Roche is set to invest $1.3bn to acquire a 56.3% stake in US-based Foundation Medicine (FMI), in a bid to expand treatment options for cancer patients.

Roche will tender 15.6 million shares at $50 per share, with an aggregate value of $780m, and will also invest $250m in the company by acquiring five million newly issued shares at $50 per share.

The deal will enhance FMI's position in molecular information and genomic analysis, which helps Roche to optimise the identification and development of new treatment options for cancer patients.

Roche Pharma chief operating officer Daniel O'Day said: "By combining FMI's pioneering approach to genomics and molecular information with Roche's expertise in the field of oncology, we can bring personalised healthcare in oncology to the next level."

Roche will provide R&D funding of $150m for a minimum of five years, in addition to contributing its expertise in oncology.

FMI will contribute its experience to develop comprehensive genomic profiling tests for oncology.

The R&D collaboration will develop genomic profile tests for cancer immunotherapies and continuous blood-based monitoring.

Foundation Medicine president Michael Pellini said: "We are excited to announce this strategic collaboration with Roche, which will help accelerate our business, and importantly, represents significant potential for individuals with cancer around the world.

"We believe that putting molecular information at the center of cancer care will help transform the delivery of care for patients and speed the pace of drug discovery and development."

Both firms also accepted a commercial collaboration agreement designed to enhance FMI's position across clinical and molecular information markets.

The deal will allow Roche to acquire ex-US rights of existing FMI products, as well as future co-developed products. Roche noted the deal is expected to be completed in the second quarter of 2015.