Emerging Drug Therapies
These are exciting days in the CML Community as more and more options are making their way into the patient's tool chest. Many of the drugs and therapies listed below are either currently in clinical trials or soon to be. This page will be updated regularly as information becomes available.
Novartis - ABL001
ABL001 is a small molecule designed to inhibit BCR-ABL, the same protein targeted by imatinib and nilotinib. The difference is in the mechanism of action. ABL001 doesn't bind to the BCR-ABL protein as the other drugs, it binds to a different region altogther forcing a comformational change that disables the protein's active binding site. In other words, it changes the "shape" of the protein which in turn alters the shape of the binding site. Preclinical models have shown that the end results are the same - BCR-ABL is inhibited.
Stemline Therapeutics - SL-401
SL-401, a novel therapeutic targeting the interleukin-3 receptor (IL-3R) that is overexpressed on the CSCs and tumor bulk of a wide range of hematologic cancers, is entering pivotal clinical trial programs for BPDCN and AML, as well as clinical evaluations in several other hematologic malignancies (including CML). SL-401 has been shown to be well-tolerated and non-toxic to the bone marrow.
At the 2013 meeting of the European Society of Hematology/International CML Foundation, MD Anderson Cancer Center presented studies detailing SL-401's notable activitiy against CML primary blasts and cancer stem cells (CSCs) in animal models and in vitro. SL-401 significantly reduced the growth of CML blasts, as well as CSCs from patients with tyrosine kinase inhibitor (TKI)-resistant CML. Additionally, the combination of SL-401 and the TKI, imatinib, had a significant synergistic effect on inhibiting the growth of primary CML cells from patients. SL-401 also prolonged the survival of mice inoculated with primary cells from a CML patient in blast crisis who was resistant to several TKIs.
CytRx - Bafetinib (formerly INNO-406)
Bafetinib is a potent, orally available, rationally designed, dual Bcr-Abl and Lyn kinase inhibitor, which was developed as a third-line treatment for patients with CML and certain forms of acute myeloid leukemia (AML) that are refractory or intolerant of other approved treatments. In a Phase 1, dose-ranging clinical trial, Bafetinib demonstrated clinical responses in patients with CML and other leukemias that have the Philadelphia Chromosome that have proven intolerant of, or resistant to Gleevec® and, in some cases, second-line therapies.
Bafetinib was granted Orphan Drug Status for the treatment of Ph+ CML in 2010.
Deciphera - Rebastinib (formerly DCC-2036)
Rebastinib is a novel small molecule inhibitor which was designed to bind within an unique region of BCR-ABL kinase known as the ‘switch pocket’. This unique mode of action enables Rebastinib to retain high potency against major clinically resistant mutations (including the gatekeeper T315I mutation) which can lead to drug resistance and disease recurrence. Preclinical data summarizing these properties of Rebastinib have been accepted for publication in the journal Cancer Cell and published online on April 12, 2011. Rebastinib is orally bio-available and has a narrow spectrum of kinase inhibition. A Phase 1 study in 57 patients with Philadelphia positive (Ph+) chronic myelogenous leukemia (CML) and the T315i mutation was completed in January 2013. For more information on trials for this drug, visit http://clinicaltrials.gov/ct2/show/NCT00827138.
Nerviano Medical Sciences - Danusertib
Danusertib is an Aurora Kinase Inhibitor which also shows inhibitory activity against the Bcr-Abl tyrosine kinase, including its multidrug-resistant T315I mutant. This mutation is responsible for up to 25% of all clinically observed resistances in CML patients undergoing Imatinib therapy. The combined kinase inhibition of Danusertib represents a promising new strategy for Bcr-Abl positive leukemias Aurora are a family of serine/threonine kinases acting as key mitotic regulators required for genome stability. Aurora are involved in regulating multiple steps in mitosis, including centrosome duplication, formation of a bipolar mitotic spindle, and chromosome alignment on the mitotic spindle.