Informed by our communications with the FDA, we are recruiting patients in a global
randomized Phase 2 study evaluating the efficacy, safety, and tolerability of
ME-401
in patients with FL after failure of at least two prior systemic therapies including chemotherapy and an anti-CD20
antibody. The study will evaluate both the CS and IS dosing regimens; in one arm,
ME-401
will be administered once daily continuously and in the other arm,
ME-401
will be administered once daily for two cycles (i.e., eight weeks) followed by an intermittent schedule whereby
ME-401
will be administered once daily for the first seven days of a
28-day
cycle followed by 21 days of placebo. Approximately 150 patients will be randomized in the study and the primary efficacy endpoint will be the rate of objective response to therapy.
Voruciclib: CDK Inhibitor with CDK9 Inhibition in Phase 1 Studies
Voruciclib is an orally administered CDK inhibitor differentiated by its potent in vitro inhibition of CDK9 in addition to CDK6, 4 and 1.
Voruciclib is currently being evaluated in a Phase 1b dose ranging study in patients with
B-cell
malignancies.
Voruciclib Scientific Overview: Cell Cycle Signaling
The CDK family of proteins are important cell cycle regulators. CDK9 is a transcriptional regulator of the myeloid leukemia cell
differentiation protein (MCL1), a member of the family of anti-apoptotic proteins which, when elevated, may prevent the cell from undergoing cell death. Inhibition of CDK9 blocks the production of MCL1, which is an established resistance
mechanism to the
B-cell
lymphoma (BCL2) inhibitor venetoclax (marketed as Venclexta).
In
pre-clinical
studies voruciclib shows dose-dependent suppression of MCL1; in December 2017 a study
of voruciclib published in the journal
Nature Scientific Reports
reported that the combination of voruciclib plus the
BCL-2
inhibitor venetoclax was capable of inhibiting two master regulators of cell
survival,
MCL-1
and
BCL-2,
and achieved synergistic antitumor efficacy in an aggressive subset of DLBCL
pre-clinical
models.
(Scientific Reports. (2017) 7:18007.
DOI:10.1038/s41598-017-18368-w).
CDK9 is also a transcriptional regulator of MYC, a transcription factor regulating cell proliferation and growth which contributes to many
human cancers and is frequently associated with poor prognosis and unfavorable patient survival. Targeting MYC directly has historically been difficult, but CDK9 is a transcriptional regulator of MYC and is a promising approach to target this
oncogene.
Clinical Program
In January 2018, we announced the FDA cleared the voruciclib Investigational New Drug Application (IND) for hematologic
malignancies. In August 2018 we dosed our first patient in a dose ranging Phase 1b clinical trial of voruciclib. The study is intended to evaluate voruciclib as a single agent in patients with relapsed and/or refractory
B-cell
malignancies or acute myeloid leukemia (AML) after failure of prior standard therapies to determine the safety, preliminary efficacy and maximum tolerated dose. We also plan to evaluate voruciclib
in combination with venetoclax to assess synergies and the opportunity for combination treatments across multiple indications.
Voruciclib
was previously evaluated in more than 70 patients in multiple Phase 1 studies with a tolerability profile consistent with other drugs in its class. In
pre-clinical
studies, voruciclib shows dose-dependent
suppression of MCL1 at concentrations achievable with doses that appear to be generally well tolerated in earlier Phase 1 studies.
Pre-clinical
studies additionally show inhibition of MYC protein expression.
ME-344:
Mitochondrial Inhibitor with Combinatorial Potential
ME-344
is our novel and tumor selective, isoflavone-derived mitochondrial inhibitor drug candidate. It
directly targets the OXPHOS complex 1, a pathway involved in ATP production in the mitochondria.
ME-344
is under evaluation in an investigator-initiated, multi-center, randomized study in combination with the
vascular endothelial growth factor (VEGF) inhibitor bevacizumab (marketed as Avastin
®
) in a total of 40 patients with HER2
negative breast cancer.
ME-344
Scientific Overview: Cancer Metabolism
Tumor cells often display a high metabolic rate to support cell division and growth. This heightened metabolism requires a continual supply of
energy in the form of adenosine triphosphate (ATP). The two major sources of ATP are the specialized cellular organelles termed mitochondria and through the metabolism of carbohydrates, proteins and lipids.
ME-344
was identified through a screen of more than 400 new chemical structures originally created
based on the central design of naturally occurring plant isoflavones. We believe that some of these synthetic compounds, including our drug candidate
ME-344,
interact with specific mitochondrial enzyme
targets, resulting in the inhibition of ATP generation. When these compounds interact with their target, a rapid reduction in ATP occurs, which leads to a cascade of biochemical events within the cell and ultimately to cell death.
Clinical Program
ME-344
demonstrated evidence of single agent activity against refractory solid tumors in a Phase 1 study, and in
pre-clinical
studies tumor cells treated with
ME-344
resulted in a rapid loss of ATP and cancer cell death. In addition to single agent activity,
ME-344
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