US developer, Mersana Therapeutics, secured its third significant antibody drug conjugate (ADC) alliance of 2022 in December. It is a research collaboration and commercial license agreement with Merck KGaA, based in Darmstadt, Germany.
The partnership involves the development of two novel immunostimulatory ADCs leveraging Mersana’s Immunosynthen platform and antibodies from Merck.
Along with this deal, Mersana also inked agreements with two other pharma giants last year – with GSK in August last year and with Janssen in February. The three alliances have netted US$170m in upfront payments for Mersana, together with over US$3bn in total potential milestones, plus royalties.
Terms of the deal
Under the terms of the Merck deal, Mersana will receive an upfront payment of US$30m and up to US$800m in potential regulatory, development and commercial milestone payments, plus tiered royalties up to the low double-digit percentages on worldwide net sales of any approved ADCs developed under the agreement.
The Cambridge, Massachusetts headquartered firm will be responsible for certain discovery activities, as well as limited preclinical manufacturing and supply obligations, which will be reimbursed by Merck.
Merck will be solely responsible for in vitro and in vivo characterization, other preclinical work, and all clinical development and potential commercialization activities relating to any resulting product candidates.
Targeting the tumor microenvironment
Mersana has three proprietary ADC platforms, two of which carry cytotoxic payloads while a third carries an immunostimulatory payload. That third platform is designed to create ADCs that are systemically administered and locally activate STING signaling in both tumor-resident immune cells and tumor cells, unlocking the anti-tumor potential of innate immune stimulation.
Paul Lyne, head of the oncology research unit, at Merck KGaA, commenting on the tie-up, said: “An approach that can directly target the tumor microenvironment with an immunomodulatory ADC has the potential to bring the benefits of this immunotherapy to a broader group of patients. This collaboration with Mersana to design novel immunostimulatory ADCs that can harness the potential of the STING pathway is an ideal complement to our innovation in this area.”
In other ADC alliances, LegoChem Biosciences (LCB) has entered into a research collaboration and license agreement with Amgen.
The South Korean company has granted Amgen the rights to research, develop, and commercialize ADCs, directed against up to five targets, based on its technology.
The collaboration sees LCB set to receive up to US$1.25bn including upfront, development and commercial milestone payments, with it also eligible to collect tiered royalties as a percentage of worldwide commercial sales by Amgen.
“This licensing agreement demonstrates LCB’s continued recognition as an industry-leading ADC player and further enhances our ability to innovate through global partnership as we build out our pipeline and accelerate our transformation into a fully-integrated oncology company,” noted Yong-Zu Kim, CEO of LCB.
The Asian company said its clinical-stage ConjuAll ADC platform is designed to provide optimized site-specific conjugation, as well as cancer-selectively activating linker and payload technologies for ADCs, thus enabling the development ADCs with a wider therapeutic window and improved manufacturability.