AMSTERDAM, NETHERLANDS – July 23, 2020 – Synaffix B.V., a biotechnology company
focused on enabling antibody-drug conjugates (ADCs) with superior therapeutic index based
on its proprietary ADC technology platform, announces that ADC Therapeutics SA has
expanded its existing collaboration to explore additional applications, including DAR1, of
Synaffix’ site-specific conjugation technologies.

Under the expanded collaboration, ADC Therapeutics has been granted non-exclusive rights
for two additional programs, which brings the total number of programs using Synaffix’ ADC
technologies to five. ADC Therapeutics also gains access to the latest innovative extensions of
Synaffix’ proprietary GlycoConnect™ platform, including DAR1 technology that enables stable
attachment of just a single drug per antibody.

Synaffix is eligible to receive upfront, milestone and royalty payments tied to each program.
Further financial details are not disclosed.

Peter van de Sande, CEO of Synaffix said:
“We are very pleased to see the rapid progression of ADC Therapeutics’ programs that have
been developed using our GlycoConnect ADC technology platform, and the multiple
collaboration expansions that have followed our original agreement.
“We look forward to continuing to work closely with the ADC Therapeutics team as they
translate more product candidates using GlycoConnect into the clinic.”

Synaffix entered into the original commercial license agreement with ADC Therapeutics in
October 2016. ADC Therapeutics is responsible for the research, development, manufacturing
and commercialization of any resulting ADC products, and Synaffix is responsible for the
manufacturing of components specifically related to its proprietary ADC technologies.

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