Idasanutlin (RG-7388) is a second-generation, orally bioavailable, selective p53-MDM2 antagonist. MDM2 is an important negative regulator of the p 53 tumor suppressor and is expressed at high levels in a large proportion of acute myeloid leukemia (AML). Blocking the MDM2-p53 interaction stabilizes p53 and activates p-53 mediated cell death and inhibition cell growth. Idasanutlin is under clinical trial in phase III for treatment AML and in combinations with others drugs in phase I/II for treatment of multiple myeloma.

Sitravatinib (MGCD516) is a receptor tyrosine kinases (RTK) inhibitor that blocks a wide array of RTKs known to be amplified/overexpressed in sarcomas, which are key regulators of signaling pathways that lead to cell growth, survival and tumor progression. It is involved in driving sarcoma cell growth with IC50 of 3980 nM and is superior to other multi-kinase inhibitors in inhibiting cell proliferation, RTK phosphorylation, and phosphorylation of downstream effectors. The efficacy of sitravatinib was tested using a wide panel of sarcoma cell lines, including malignant peripheral nerve sheath tumor (MPNST), Ewing sarcoma (A673), osteosarcoma (Saos2), and liposarcoma (DDLS, LS141). Both in vitro and in vivo efficacy sitravatinib was significantly better that the other two multi-kinase inhibitors, imatinib and crizotinib. Sitravatinib treatment not only inhibits tumor cell proliferation at low nanomolar concentrations in vitro but also results significant tumor growth suppression in vivo in mouse xenograft models. Sitravatinib is being evaluated in a Phase 1b dose expansion cohort in selected patients with specific genetic alterations that are drivers of tumor growth, with an initial focus on Non-Small-Cell Lung carcinoma (NSCLC) and in other solid tumors where sitravatinib may confer a benefit. Its efficacy and safety is also being tested in Phase II clinical trials in patients with advanced liposarcoma as a monotherapy and NSCLC in combination with nivolumab.

MPC-3100 is a fully synthetic, orally bioavailable, Hsp90 inhibitor developed by Myriad Pharmaceuticals, Inc for cancer treatment. MPC-3100 targets the N-terminal ATP-binding site of Hsp90 and blocks the activity of ATPase. MPC-3100 shows a broad spectrum anti-proliferative activity against various cancer cell lines, such as HCT-116, NCI-N87 and DU-145. MPC-3100 also inhibits tumor growth in the NCI-N87 gastric cancer xenograft mode. Moreover, pharmacokinetics studies show that MPC-3100 displays a superior oral pharmacokinetics profile, good overall exposure and a reasonable hepatic clearance rate. Phase I clinical studies demonstrate MPC-3100 is safe and tolerated when administered at doses below 600 mg per day