This is a phase 2 study of investigational drug niraparib and TSR-042 in patients with
advanced/recurrent endometrial cancer. The purpose of this study is to determine whether
blocking a protein called poly (ADP-ribose) polymerase (PARP) with niraparib provides
clinical benefit in patients with recurrent endometrial cancer, as well as to explore the
possible impact of phosphatase and tensin homolog (PTEN) loss (loss of function of the PTEN
gene) on blocking PARP with niraparib.