A Phase I/IIa, Open-label, Multi-center Study to Assess the Safety, Tolerability, Pharmacokinetics and Preliminary Efficacy of the DNA Polymerase Theta Inhibitor ART6043 Administered Orally as Monotherapy and in Combination to Patients with Advanced or Metastatic Solid Tumors

• ART6043 is a Polθ inhibitor

In this study, the sponsor and investigators want to learn:

• How much of the study can be given alone and in combination with Olaparib or Talazoparib with an acceptable level of side effects
• The effects of the study alone and in combination with Olaparib or Talazoparib (good and bad)
• How much of the study is absorbed into the blood and how fast it is removed
• How the study is acting on your body, on tumors and the substances in your body that can be used to monitor how your disease is doing
• If research tests can be used in the future to predict who will benefit from the study drug when given alone or in combination with Olaparib or Talazoparib

This is a dose escalation/expansion study. Dose Escalation means that the amount of the study given will be increased in each group of research participants, to find the most appropriate dose for further study. In the dose expansion part of the study, a larger number of people receive the study drug dose determined to be appropriate in the dose escalation part of the study.

The study regimen will be given in cycles.  Each cycle is 21 days.

If you are enrolled in Part A1, you will take the study  as a tablet by mouth, once daily with a full glass of water (at least 8 ounces).

If you are enrolled in Part A2, you will be taking the study drug with Olaparib. You will receive 1 single dose of Olaparib 1 day prior to starting the study drug regimen. Following this visit, you will take the Olaparib as a tablet by mouth, twice daily in combination with the study drug.

If you are enrolled in Part A3, you will be taking the study drug with Talazoparib. You will take the Talazoparib as a capsule by mouth, once daily in combination with the study drug.

You will need to take each dose at about the same time each day that you are supposed to take a dose and the whole dose should be taken at once.