Figure S1, Figure S2, Figure S3, Figure S4 from Co-clinical Trial of Novel Bispecific Anti-HER2 Antibody Zanidatamab in Patient-Derived Xenografts

Supplementary Figure 1: HER2 status of patients and corresponding PDX models. HER2 expression was assessed by IHC and ERBB2 amplification status by FISH and NGS. FISH, fluorescence in situ hybridization; HER2, human epidermal growth factor receptor 2; NGS, next-generation sequencing. Alterations represents genomic alterations in available CLIA genomic testing on archival patient samples (matching PDX hosts). CLIA results were not available for patients matching PDX.003.025, PDX.003.263, and PDX.003.230.

Supplementary Figure 2: Actionable gene alterations in patient biopsies compared to the alteration in the resulting PDX as determined by whole exome sequencing on both.

Supplementary Figure 3: Cell viability assay with crizotinib. Cells were treated with crizotinib at serial dilutions for 72 hours. Following SRB staining, IC50 was calculated using CalcuSyn.

Supplementary Figure 4. In vivo assessment of zanidatamab in combination with BET inhibitor JQ1. 50 mg/kg JQ1 had no antitumor effects as single agent and did not add benefit when combined with 16 mg/kg zanidatamab.