Pacritinib (SB1518), discovered in Singapore at the labs of S*BIO Pte Ltd., is an oral tyrosine kinase inhibitor (TKI) with activity against two important activating mutations: Janus Associated Kinase 2 (JAK2) and FMS-like tyrosine kinase 3 (FLT3). The JAK family of enzymes is a central component in signal transduction pathways, which are critical to normal blood cell growth and development as well as inflammatory cytokine expression and immune responses. Activating mutations of JAK2 are implicated in certain blood-related cancers, including myeloproliferative neoplasms (MPNs), leukemia and certain solid tumors. FLT3 is a gene commonly found mutated in patients with acute myeloid leukemia (AML). Pacritinib has demonstrated encouraging results in Phase 1 and 2 studies for patients with myelofibrosis and may offer an advantage over other JAK inhibitors through effective treatment of symptoms while having less treatment-emergent thrombocytopenia and anemia than has been seen in currently approved and in-development JAK inhibitors. Pacritinib is acquired by Cell Therapeutics, Inc. (CTI) and Baxter international and could effectively address an unmet medical need for patients living with myelofibrosis who face treatment-emergent thrombocytopenia on marketed JAK inhibitors. Currently Pacritinib is undergoing preregistration for myelofibrosis.

ABL-001 (asciminib), a potent and selective allosteric tyrosine-protein kinase ABL1 inhibitor that is undergoing clinical development testing in patients with Chronic myeloid leukemia (CML) and Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia. is a tyrosine-protein kinase ABL1 inhibitor. In contrast to catalytic-site ABL1 kinase inhibitors, ABL001 binds to the myristoyl pocket of ABL1 and induces the formation of an inactive kinase conformation. ABL001 and second-generation catalytic inhibitors have similar cellular potencies but distinct patterns of resistance mutations, with genetic barcoding studies revealing pre-existing clonal populations with no shared resistance between ABL001 and the catalytic inhibitor nilotinib. ABL001 was tested on mice with a particularly aggressive type of CML. The combination of ABL001 and nilotinib led to complete disease control and eradicated CML xenograft tumors without recurrence after the cessation of treatment. ABL001 is being tested in clinical trials for treatment of CML and Philadelphia Chromosome-positive Acute Lymphoblastic Leukemia alone and in combination with niotinib, imatinib or dasatinib.

Maribavir (previously known as 1263W94) is a novel benzimidazole riboside compound. This drug was in phase III of clinical trial for the prevention of cytomegalovirus (CMV) infections in transplant patients, sponsored by ViroPharma. However, drug failed to demonstrate a higher efficacy rate than the placebo. Maribavir has activity against cytomegalovirus and Epstein-Barr virus (EBV), but not against other human herpesviruses. Maribavir’s mechanism of action is unique and is complex compared to the currently approved antivirals for CMV. Maribavir inhibits the viral UL97 kinase rather than the viral DNA polymerase. The UL97 kinase is important for viral DNA elongation, DNA packaging, and nuclear egress of encapsidated viral DNA. In addition, maribavir inhibits the EBV DNA polymerase processivity factor (BMRF1), reduces the level of certain EBV glycoproteins, and inhibits viral transcription. However, future work will be designed to address the interaction of MBV and BGLF4 and to evaluate the mechanisms through which maribavir downregulates viral transcripts. BGLF4 belongs to the family of conserved herpesvirus PKs, which includes HCMV UL97, HSV UL13, and HSV US3. Maribavir does need to be phosphorylated for its activity.

Trilaciclib (Cosela™) is a small-molecule, short-acting, inhibitor of cyclin-dependent kinases (CDK) 4 and 6 developed by G1 Therapeutics for its myeloprotection and potential antitumor efficacy and safety benefits in combination with cancer chemotherapy. CDKs govern cell cycle progression, and trilaciclib induces a transient, reversible G1 cell cycle arrest of proliferating haematopoietic stem and progenitor cells in bone marrow, thus protecting them from damage during chemotherapy. In February 2021, trilaciclib received its first approval in the USA to decrease the incidence of chemotherapy-induced myelosuppression in adult patients when administered prior to a platinum/etoposide-containing regimen or topotecan-containing regimen for extensive-stage small cell lung cancer (ES-SCLC). Clinical studies in breast cancer, colorectal cancer and small cell lung cancer are underway in several countries.

Tepotinib is an investigational small molecule inhibitor of the c-Met receptor tyrosine kinase. Alterations of the c-Met signaling pathway are found in various cancer types and correlate with aggressive tumor behavior and poor clinical prognosis. Tepotinib is a potent and selective c-Met inhibitor, >200-fold selective for c-Met than IRAK4, TrkA, Axl, IRAK1, and Mer. Tepotinib is currently in Phase I/II trials in liver cancer and lung cancer.

KD025 is an orally available, selective small molecule inhibitor of ROCK2 (Rho-associated coiled-coil kinase 2), a molecular target in multiple autoimmune, fibrotic and neurodegenerative diseases. KD025 is the only ROCK2-specific inhibitor in the clinical trials. KD025 down-regulates the IL-17 and IL-21 secretion in human PBMCs, and leads to down-regulation of STAT3 phosphorylation, IRF4, and RORγt expression in CD4+ T cells. Kadmon Pharmaceuticals initiated phase II clinical trials of KD025 for the treatment of Graft-versus-host disease; Idiopathic pulmonary fibrosis; Plaque psoriasis.

Capmatinib (INC280, INCB028060), is an orally bioavailable inhibitor of the proto-oncogene c-Met (hepatocyte growth factor receptor [HGFR]) with potential antineoplastic activity. Novartis acquired Incyte's capmatinib, which is in Phase II clinical trial as monotherapy in patients with advanced hepatocellular carcinoma. Capmatinib selectively binds to c-Met, thereby inhibiting c-Met phosphorylation and disrupting c-Met signal transduction pathways. This may induce cell death in tumor cells overexpressing c-Met protein or expressing constitutively activated c-Met protein. c-Met, a receptor tyrosine kinase overexpressed or mutated in many tumor cell types, plays key roles in tumor cell proliferation, survival, invasion, metastasis, and tumor angiogenesis.

Pemigatinib, an oral kinases inhibitor, was approved under the brand name PEMAZYRE for the treatment of adults with previously treated, unresectable locally advanced, or metastatic cholangiocarcinoma with a fibroblast growth factor receptor 2 (FGFR2) fusion. The FDA-approved indication for pemigatinib was granted under accelerated approval based on the overall response rate and duration of response in pre-marketing clinical trials. The drug inhibited FGFR1-3 phosphorylation and signaling and decreased cell viability in cancer cell lines with activating FGFR amplification and fusions that resulted in constitutive activation of FGFR signaling.

TUCATINIB (ONT-380 or ARRY-380) is an orally active, reversible and selective small-molecule HER2 inhibitor invented by Array and licensed to Cascadian Therapeutics (previously named Oncothyreon) for development, manufacturing and commercialization. HER2, a growth factor receptor that is over-expressed in multiple cancers, including breast, ovarian, and stomach cancer. HER2 mediates cell growth, differentiation and survival, and tumors that overexpress HER2 are more aggressive and historically have been associated with poorer overall survival compared with HER2-negative cancers. ONT-380 is highly active as a single agent and in combination with both chemotherapy and Herceptin® (trastuzumab) in xenograft models of HER2+ breast cancer, including models of CNS metastases that were refractory to Tykerb® (lapatinib) or neratinib treatment. In a Phase 1 single agent clinical study, ONT-380 administered orally twice a day was well tolerated and demonstrated anti-tumor activity in heavily pre-treated HER2+ breast cancer patients with metastatic disease. Based on the strength of these preclinical and clinical trials, ONT-380 is advancing in one Phase 2 and three Phase 1b combination trials in patients with metastatic breast cancer. A second study reported the CNS activity of ONT-380 in combination with either T-DM1 or trastuzumab or capecitabine. Patients with brain metastases assessable for response were included in the combined analysis. Responses and clinical benefit in the CNS were reported with the three combinations tested, supporting future development of the drug for this particular indication.

Osilodrostat (INN, USAN) (developmental code name LCI-699) is an orally active, non-steroidal corticosteroid biosynthesis inhibitor which is under development by Novartis for the treatment of Cushing's syndrome and pituitary ACTH hypersecretion (a specific subtype of Cushing's syndrome). Osilodrostat specifically acts as a potent and selective inhibitor of aldosterone synthase (CYP11B2) and at higher dosages of 11β-hydroxylase (CYP11B1). Osilodrostat decreases plasma and urinary aldosterone levels and rapidly corrects hypokalemia, in patients with primary aldosteronism and hypertension. At doses ≥1 mg o.d. Osilodrostat markedly increases 11-deoxycortisol plasma levels and blunts ACTH-stimulated cortisol release in ≈20% of patients, consistent with the inhibition of CYP11B1. In patients with resistant hypertension, Osilodrostat produces a non-significant reduction in blood pressure, possibly due to the increase in 11-deoxycortisol levels and the stimulation of the hypothalamic-pituitary-adrenal feedback axis. Because of the lack of selectivity, poor antihypertensive effect, and short half-life, the development of Osilodrostat as antihypertensive was halted. As of 2017, Osilodrostat is in phase III and phase II clinical trials for the treatment of pituitary ACTH hypersecretion and Cushing's syndrome, respectively.