Phase 1 Study to Assess Safety, Tolerability, Pharmacokinetics, Immunogenicity, and Antitumor Activity of ARR-002 in Advanced or Metastatic Ovarian or Endometrial Cancer.

This is an open-label, multicenter Phase 1a/1b dose-escalation/expansion, consecutive-cohort, to assess safety, tolerability, pharmacokinetics, immunogenicity, and preliminary antitumor activity of ARR-002 in adults with locally advanced or metastatic ovarian or endometrial cancer. The study will consist of 2 main parts: * Phase 1a will enroll participants with platinum-resistant ovarian cancer (PROC). This dose-escalation portion will assess the safety and tolerability of ARR-002. * Phase 1b will enroll cohorts of participants by cancer type; platinum-resistant ovarian cancer (PROC) and endometrial cancer.