Forma Therapeutics added Boehringer Ingelheim to its growing list of partners in a deal to discover and develop new cancer drugs against targets that until now have been considered un-druggable. The partnership will use Forma’s technology to discover small molecule drugs against cancer-relevant protein-protein interactions.

The company uses computational and medicinal chemistry, parallel synthesis, X-ray crystallography and relevant biology studies to identify and optimize potentially useful molecules.

As part of their deal, Forma will receive $65 million in upfront payments and research funding to screen for and optimize compounds against multiple cancer targets over the next four years. The Boston-area startup could also get up to another $750 million in pre-commercial milestones for programs resulting from the collaboration.

While further details of the deal were not disclosed, Forma CEO Steven Tregay said in a statement that the agreement offered the company and its shareholders several opportunities to realize an early return through the assets developed under the collaboration.

Since its founding in 2007 by a group of scientists from MIT’s Broad Institute and Harvard, Forma has leveraged an array of partnerships to build a robust pipeline of cancer therapies in areas such as tumor metabolism, protein-protein interactions, and epigenetics. The company counts Novartis, Cubist Pharmaceuticals, Eisai, and, Genentech among its partners.

Forma struck an option deal with Genentech in June 2011, granting the Roche division exclusive worldwide rights to acquire a preclinical small molecule program against a single undisclosed cancer target. The deal includes an upfront payment and research funding, plus potential milestone payments, and a significant buyout payment plus additional milestones should Genentech exercise its option to acquire the program at a defined future phase of development.

The startup has raised only $33 million to date, relying on partnerships to advance its therapeutic pipeline. It is backed by Novartis Option Fund, Bio*One Capital of Singapore, Cubist Pharmaceuticals, and Lilly Ventures. Tregay was a managing director at Novartis Option Fund when he joined Forma’s management team.