This first-in-human study is designed to establish the safety and tolerability of ATR-101 in patients with advanced adrenocortical carcinoma whose tumor has progressed on standard therapy. Information will also be collected to determine how long ATR-101 stays in the blood, and if any effect on tumor progression is seen. Biomarkers (blood and urine tests) will determine if any effects on production of steroid hormones (cortisol, aldosterone, estrogen and testosterone) are seen.

Inclusion Criteria:

18 years;

• Clinical confirmation of adrenocortical carcinoma that is locally advanced or metastatic and not amendable to surgical resection;
• Failed or declined mitotane (adjuvant or therapeutic) therapy or a platinum-based chemotherapy regimen;
• Able to understand and comply with the protocol requirements;
• Willing and able to provide informed consent.

Exclusion Criteria:

• Mitotane level > 5
• Use of contraindicated concomitant medications
• Unstable medical condition that, in the judgment of the investigator, could interfere with study procedures or data interpretation.