Mersana Therapeutics Inc., a privately held oncology company, has entered into a collaboration with Chadds Ford, Penn-based Endo Pharmaceuticals (Nasdaq: ENDP), the company announced today.

The collaboration is designed to create new potential cancer therapies by using Cambridge-based Mersana’s so-called Fleximer technology to bind Endo’s novel antibody candidates to already-approved chemotherapy agents, to create antibody-drug conjugates (ADC).

The deal includes an undisclosed upfront payment and up to $270 million in potential milestones. The deal also could include royalties on any approved drugs that result from the collaboration.

“We look forward to working with Endo to incorporate their antibodies against a very promising oncology target into next-generation Fleximer-ADC candidates. We expect this to be just the first of several important Fleximer-ADC collaborations for Mersana,” CEO Nick Bacopoulos said in a statement.

Mersana is responsible for conducting research and Endo is responsible for product development, manufacturing and commercialization of any resulting products. Mersana and Endo may agree to pursue two additional targets over the next two years.

Mersana, which raised $6 million in funds in April 2011, has two of its own potential cancer therapies in development, one of which is being studied for the treatment of lung cancer in a Phase 1B study. The other is in a Phase 1 study testing it against solid tumors.