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.

Taladegib (LY2940680) is an orally bioavailable small molecule antagonist of the Hedgehog (Hh)-ligand cell surface receptor smoothened (Smo) with potential antineoplastic activity. Taladegib inhibits signaling that is mediated by the Hh pathway protein Smo, which may result in a suppression of the Hh signaling pathway and may lead to the inhibition of the proliferation of tumor cells in which this pathway is abnormally activated. The Hh signaling pathway plays an important role in cellular growth, differentiation and repair; constitutive activation of this pathway is associated with uncontrolled cellular proliferation and has been observed in a variety of cancers. Taladegib has excellent pharmacokinetic properties in rodent and non-rodent species. Taladegib administrated orally treats Ptch+/- p53-/- transgenic mice which spontaneously develop medulloblastoma, produces remarkable efficacy and significantly improves their survival. Taladegib reveals rapid kinetics of anti-tumor activity through magnetic resonance imaging of these mice, and Taladegib induces Caspase-3 activity and reduces proliferation by immunohistochemistry analysis of medulloblastoma tumors. Taladegib inhibits Hh regulated gene expression in the subcutaneous xenograft tumor stroma and produces significant anti-tumor activity. Taladegib is currently in phase I clinical trials for ovarian cancer and solid tumours and in phase I/II for esophageal cancer. Ignyta exclusively licensed Taladegib from Eli Lilly and Company in November 2015.

Altiratinib, a novel c-MET/TIE-2/VEGFR inhibitor, was able to effectively reduce tumor burden in vivo and block c-MET signaling, cell growth and migration. Altiratinib inhibits not only mechanisms of tumor initiation and progression, but also drug resistance mechanisms in the tumor and microenvironment. Altiratinib durably inhibits MET, both wild-type and mutated forms, in vitro and in vivo. Altiratinib exhibits properties amenable to oral administration and exhibits substantial blood-brain barrier penetration, an attribute of significance for eventual treatment of brain cancers and brain metastases. It is currently in Phase 1 clinical development for the treatment of solid tumors.

Pexmetinib (ARRY-614) is a potent, orally bioavailable, dual p38 MAPK/Tie-2 inhibitor with potential antineoplastic, anti-inflammatory and antiangiogenic activities. Pexmetinib inhibited leukemic proliferation, prevented activation of downstream effector kinases and abrogated the effects of TNF-alpha on healthy hematopoietic stem cells. In ex vivo stimulated human whole blood, LPS-induced cytokines was inhibited by Pexmetinib with an IC50 value ranging from 50-120 nM. ARRY-614 inhibited the release of IL-6 from SEA- or LPS-challenged mice with an ED50 value less than 10 mg/kg. Combining Pexmetinib with lenalidomide inhibited both pro-inflammatory cytokines and tumor growth in vivo with higher potency, compared with either agent alone. In dose escalation or expansion cohorts, treatment with Pexmetinib either once daily or twice daily was applied to forty-five patients. Pexmetinib reduced the levels of circulating biomarkers and the p38 MAPK activation of bone marrow.

Tirabrutinib (also known as ONO-4059 or GS-4059), a second-generation, enhanced-selectivity Bruton's tyrosine kinase inhibitor that demonstrated antitumor activity in preclinical models. Tirabrutinib participated in phase I clinical trial in patients with relapsed or refractory B-cell malignancies, where it was well tolerated and showed promising efficacy. In addition, tirabrutinib is involved in phase II clinical trials to study safety and efficacy in adults with Active Sjogren's syndrome and in adults with chronic lymphocytic leukemia. Besides the drug was studied for the treatment of Waldenstrom's macroglobulinemia and patients with refractory pemphigus.

Empesertib (previously known as BAY-1161909) was developed as a selective inhibitor of the serine/threonine monopolar spindle 1 (Mps1) kinase for the treatment of cancer. Empesertib participated in phase I clinical trials in combination with paclitaxel in subjects with advanced malignancies. The studies were terminated because another more successful Mps1 inhibitor was being developed in parallel.

PF-06747775 is an irreversible pyrrolopyrimidine inhibitor of epidermal growth factor receptor (EGFR) T790M mutants which provides potent EGFR activity against the four common mutants (exon 19 deletion (Del), L858R, and double mutants T790M/L858R and T790M/Del), selectivity over wild-type EGFR, and desirable ADME properties. The third-generation class of EGFR tyrosine kinase inhibitors PF-06747775 is a clinical candidate drug for treatment of non-small-cell lung cancer (NSCLC) driven by mutant EGFR.

ARN-810 (GDC-0810) is a novel, orally bioavailable, estrogen receptor antagonist that induces proteasomal estrogen receptor degradation in breast cancer cell lines at picomolar concentrations and tumor regression in tamoxifen-sensitive and resistant BC xenograft models. Results from a first-in-human phase I/IIa study of ARN-810 indicate that it is tolerable and may benefit some postmenopausal women with advanced estrogen receptor-positive breast cancer. Development of ARN-810 was discontinued.

PQR-309 is an orally bioavailable pan inhibitor of phosphoinositide-3-kinases (PI3K) and inhibitor of the mammalian target of rapamycin (mTOR), with potential antineoplastic activity. PI3K/mTOR kinase inhibitor PQR-309 inhibits the PI3K kinase isoforms alpha, beta, gamma and delta and, to a lesser extent, mTOR kinase, which may result in tumor cell apoptosis and growth inhibition in cells overexpressing PI3K/mTOR. By inhibiting mTOR to a lesser extent than PI3K, PQR-309 does not interfere with the mTOR-mediated negative feedback loop on PI3K signaling. Blocking the negative feedback loop would potentially increase PI3K signaling and decrease therapeutic efficacy. PQR-309 is in phase II clinical trial for the treatment of glioblastoma, head and neck cancer, lymphoma and breast cancer. Common adverse events included fatigue, hyperglycemia, nausea, diarrhea, constipation, rash, anorexia and vomiting.