Mersana Therapeutics and Merck KGaA’s EMD Serono subsidiary will team up to develop antibody-drug conjugates (ADCs) using Mersana’s Fleximer® technology. The deal could net Mersana up to $792 million in upfront and milestone payments, as well as royalties on worldwide net sales.
The companies will use Fleximer to generate ADCs for multiple undisclosed targets. Mersana and EMD Serono also agreed to test a variety of ADCs through Mersana’s platform technologies and several cytotoxic agents as conjugates.
EMD Serono agreed provide monoclonal antibodies to Mersana, which agreed in return to generate the Fleximer-ADCs, as well as conduct drug discovery and preclinical development activities. EMD Serono will be responsible for clinical development EMD Serono will be responsible for clinical development and commercialization of any products under an exclusive license from Mersana.
Fleximer uses Mersana’s biodegradable Fleximer polymer system, plus a variety of linkers designed to allow attachment of antitumor payloads to Fleximer. Once loaded with one or more drugs, Fleximer is attached through a stable linker that differs from the drug linkers to the antibody or antibody alternative to create a Fleximer-ADC.
Mersana's linker systems are designed to be stable in the blood-stream and to release their payloads once inside the targeted cancer cell. According to Mersana, its Fleximer-ADC technology provides several key advantages over currently available approaches, including: the ability to deliver diverse payloads; the opportunity to significantly increase drug loading per antibody; and the potential use with antibody fragments and alternative targeting moieties in addition to monoclonal antibodies.
Mersana's payload platforms include Dolaflexin™, an auristatin derivative; Vindeflexin™, a vindesine derivative; and Cytoflexin™, a tubulysin derivative.
“This new collaboration provides an exciting opportunity to expand our oncology drug discovery and development portfolio into the evolving ADC space,” Andree Blaukat, Ph.D., head of the Translational Innovation Platform Oncology at EMD Serono, said in a statement.
EMD Serono joins Endo International and Adimab as Mersana partners that have signed agreements to supply their antibodies toward drug development efforts that use Fleximer.