Pilaralisib is a Class 1 phosphatidylinositol 3 kinase (PI3K) family inhibitor. It is an orally bioavailable small molecule, targeting the class I PI3K family of lipid kinases. It is a pyrimidine derivatives compound discovered by Exelixis Inc.

Rapamycin is a mTOR inhibitor immunosuppressant and kinase inhibitor with both antifungal and antineoplastic properties. It selectively inhibits the transcriptional activation of cytokines.

PI3K (Phosphatidylinositol-4,5-bisphosphate 3-kinase) are a family of enzymes involved in cellular functions such as cell growth, proliferation, differentiation, motility, survival and intracellular trafficking, which in turn are involved in cancer.

Elsilimomab (also known as B-E8) is a mouse monoclonal antibody and an immunosuppressive drug. It (OPR-003) targets (and blocks) Interleukin-6. It has undergone a number of early stage clinical trails, e.g. for lymphoma and myeloma.

IDO inhibitors may help to promote an enhanced immune response against the tumor by blocking the IDO enzyme which reduces the depletion of tryptophan.