Confirmed Clinical Activity of Evorpacept + Zanidatamab
Phase Ib/II exploratory results in heavily pretreated HER2-positive metastatic breast cancer (n=24) showed an overall confirmed objective response rate (ORR) of 33% (24 patients). In the 10 patients with centrally confirmed HER2-positive disease the ORR was 60%.
Strong Efficacy in CD47-High Subset
Using a retrospective cutoff of CD47 >=20%, 5 centrally confirmed HER2-positive patients were CD47-high and all 5 achieved a confirmed response (100% ORR). Median duration of response (DOR) in responders was ~20 months and median progression-free survival (PFS) in the CD47-high group was ~22 months versus 3.4 months for CD47-low.
Consistency Across Independent Studies (Breast and Gastric)
Independent data from ASPEN-06 (HER2-positive gastric randomized Phase II) showed parallel trends: ITT response rate ~41%, higher response in HER2-retained patients (~49%+), and 65% ORR in CD47-overexpressing patients. Duration of response in the gastric CD47-high subset was ~25.5 months and median PFS ~18.4 months with hazard ratio ~0.39 in that subset, reinforcing reproducibility of the CD47 signal.
Durable Responses Observed
Responders across studies exhibited long-lasting benefit with median DORs around 20 months (breast study ~20.2 months; gastric study ~25.5 months), indicating durability consistent with an immuno-oncology mechanism.
Large Evorpacept Safety Database and Differentiated MOA
Clinical safety database exceeds 800 evorpacept-treated patients. Evorpacept is engineered without an active Fc domain to avoid macrophage activation on healthy cells, aiming to mitigate on-target hematologic toxicity associated with earlier CD47 inhibitors.
ALX2004 Progressing on Schedule
ALX2004 (EGFR-targeted ADC) is advancing through dose escalation (reported escalation up to 4 mg/kg) with enrollment progressing and an initial safety readout planned in the second half of 2026.
Corporate Execution and Financing Strength
Q1 accomplishments included completion of key hires (addition of Chief Development/COO), a financing in February anchored by strong investors that strengthened the balance sheet, and enrollment progress on ASPEN-09 (Phase II breast study planned to read out ~80 patients mid-2027).