Open Actively Recruiting

A Phase 1 Study of AB521 Monotherapy and Combination Therapies in Renal Cell Carcinoma and Other Solid Tumors


Brief Summary

The purpose of this study is to evaluate the safety and tolerability of:

  • AB521 when taken alone in participants with advanced solid tumor malignancies and clear cell renal cell carcinoma (ccRCC) during the dose escalation stage; and
  • AB521 monotherapy and AB521 in combination with cabozantinib in participants with ccRCC in the dose expansion stage
Primary Purpose
Study Type
Phase 1


Healthy Volunteers
Minimum Age
18 Years
Maximum Age

Key Inclusion Criteria:

  • Disease-specific criteria for dose escalation:
  • Participants may have any pathologically confirmed solid tumor type where no other treatment options are available
  • Disease-specific criteria for dose-expansion:
    • Histologically confirmed ccRCC
    • For AB521 monotherapy cohorts: participants must have received prior treatment in the metastatic setting with an anti-PD-1/PD-L1 therapy and a vascular endothelial growth factor receptor-targeting tyrosine kinase inhibitor (VEGFR-targeting TKI), (either individually or in combination)
    • For AB521 + cabozantinib combination therapy: participants must have received prior treatment for locally advanced or metastatic disease with anti-PD-1/PD-L1 therapy in an immediately preceding line of therapy
  • Must have at least one measurable lesion per RECIST guidance
  • Eastern Cooperative Oncology Group (ECOG) performance status score of ≤ 1

Key Exclusion Criteria:

  • Use of any live vaccines against infectious diseases (eg, influenza, varicella) within 4 weeks (28 days) of initiation of investigational product
  • Has any other clinically significant cardiac, respiratory, or other medical or psychiatric condition that might interfere with a participant's participation in the clinical study or make the administration of investigational product hazardous
  • History of trauma or major surgery within 28 days prior to the first dose of investigational product
  • For all expansion cohorts: prior treatment with an hypoxia inducible factor (HIF)-2α inhibitor. For the AB521 + cabozantinib combination cohort, any prior treatment with cabozantinib
  • Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Join this Trial

Contact our clinical trial navigators for opportunities that may be suitable for you
Study Stats
Protocol No.
Kidney Cancer
  • UCLA Santa Monica
  • UCLA Westwood
For Providers
For detailed technical eligibility, visit