A Phase 1b Dose Escalation and Expansion Trial to Investigate the Safety, Tolerability, Pharmacokinetics, and Biological Activity of ATRC-101 as Monotherapy and in Combination With Other Anticancer Agents in Adults With Advanced Solid Malignancies

For the monotherapy cohorts, including the efficacy expansion cohorts, enrollment is restricted to adults with inoperable, locally advanced or metastatic breast cancer, NSCLC, CRC, ovarian cancer, and acral melanoma, which are all tumor types that have demonstrated ATRC-101 immunoreactivity on at least 50% of tested commercially procured archival specimens.

For the pembrolizumab combination therapy cohort, enrollment is restricted to adults with inoperable, locally advanced or metastatic NSCLC, CRC (only MSI-H or dMMR), melanoma (with the exception of uveal melanoma), HCC, HNSCC, ESCC, UC or TNBC, that have been treated with anti-PD-1 or anti-PD-L1 therapy and have progressed radiographically or have achieved stable disease for a minimum of two months and who, in the judgment of their treating physicians, could benefit from a combination of ATRC 101 and pembrolizumab.

For the PLD combination therapy cohort, enrollment is restricted to adult females with inoperable, locally advanced or metastatic high-grade serous epithelial ovarian, fallopian tube, or primary peritoneal cancer that is platinum resistant, defined as progression during or within 6 months of the last dose of platinum-based chemotherapy OR breast cancer that is refractory to other standard therapies.

For target-enriched expansion cohorts, enrollment will be limited to participants with pretreatment tumor biopsies demonstrating ATRC-101 target expression above a predefined threshold by IHC at a central laboratory.