Molecular Partners to Present Preclinical Data from MP0317, AMG 506 / MP0310 and Peptide-MHC Programs at AACR Annual Meeting

Zurich-Schlieren, Switzerland, May 15, 2020. Molecular Partners AG (SIX: MOLN), a clinical-stage
biotech company that is developing a new class of custom-built protein therapeutics known as
DARPin® therapeutics, today announced the presentation of preclinical data from three of the
company’s programs at the American Academy for Cancer Research (AACR) Virtual Annual
Meeting II, June 22-24, 2020.
Data to be presented on MP0317 (FAP x CD40) include in vitro and in vivo experiments which show
that MP0317 displays significant tumor-localized immune activation without systemic toxicity seen
with anti-CD40 antibody administration. In human B cells and dendritic cells, MP0317 was found to
activate the CD40 pathway solely in the presence of fibroblast activation protein (FAP)-positive cells,
confirming its strict dependence on FAP-mediated crosslinking. In a mouse model, a mouse-specific
FAP x CD40 DARPin® molecule was found to substantially inhibit the progression of FAP-positive
tumors without showing any of the toxicities seen with administration of a mouse CD40 antibody.
FAP is a tumor-associated antigen abundantly expressed in many solid tumors, which Molecular
Partners is leveraging to co-locate MP0317 to its target tissues.
Data to be presented on the peptide-MHC DARPin® program review the creation of bispecific
DARPin® T cell engager proteins that bind with high specificity to a HLA-A2: SLL peptide-MHC
complex. The constructed DARPin® proteins were observed to effectively activate T cells at a range
of concentrations and to carry out highly targeted cell killing exclusively on those cells that were
positive for NY-ESO-1, from which the SLL peptide is derived. This demonstrates proof-of-concept for
the ability of DARPin® therapeutics to effectively drug peptide-MHC complexes.
Thirdly, a poster to be presented on AMG 506 / MP0310 (FAP x 4-1BB) describes pharmacokinetic
and pharmacodynamic research to establish the optimal dose range for this novel tumor-localized
immune agonist. AMG 506 / MP0310 is now in a Phase 1 clinical study.

Media release