Novel Substituted Pyridazines as Splicing Modulators for Modulating Splicing of mRNA and Uses Thereof for Treating Diseases

Important Compound Classes

Title

Methods and Compositions for Modulating Splicing

Patent Publication Number

WO 2020/163647 A1

Publication Date

August 13, 2020

Priority Application

US 62/801,729; US 62/801,730

Priority Date

February 6, 2019; February 6, 2019

Inventors

Luzzio, M.; Lucas, B.

Assignee Company

Skyhawk Therapeutics Inc., USA

Disease Area

Cancers and noncancers, include but not limited to, cystic fibrosis, diabetes, Alzheimer’s disease, Huntington’s disease, Parkinson’s disease, pain, muscular dystrophy, cardiomyopathies, hemophilia, NASH, spinal muscular atrophy, α- or β-thalassemia

Biological Target

mRNA

Summary

The majority of protein-coding genes in the human genome are composed of multiple exons (coding regions) that are separated by introns (noncoding regions). Gene expression results in a single precursor mRNA (pre-mRNA). The intron sequences are subsequently removed from the pre-mRNA by a process called splicing, which results in mature mRNA (mRNA). By including different combinations of exons, alternative splicing gives rise to multiple mRNAs encoding distinct protein isoforms. The spliceosome, an intracellular complex of multiple proteins and ribonucleoproteins, catalyzes splicing.

Current therapeutic approaches to direct and control mRNA expression require methods such as gene therapy, genome editing, or a wide range of oligonucleotide technologies (antisense, RNAi, etc.). Gene therapy and genome editing act upstream of transcription of mRNA by influencing the DNA code and thereby changing mRNA expression. Oligonucleotides modulate the action of RNA via canonical base/base hybridization.

Another potential therapeutic approach to modulate the action of RNA is using small molecules. Small molecules have been essential in uncovering the mechanisms, regulations, and functions of many cellular processes, including DNA replication, transcription, and translation. This approach offers benefits such as easy administration (e.g., oral administration), easy penetration into cell membranes or target organs, and better absorption. In addition, RNA secondary structure can be annotated from its sequence, thus allowing identification of functional regions that could be targeted by small molecules. Targeting the RNA transcriptome with small molecule modulators represent an untapped therapeutic approach to treat a variety of RNA-mediated diseases by modulating splicing.

The present application describes a series of novel substituted pyridazines as splicing modulators that bind and modulate splicing of mRNA and uses thereof in treating various diseases. Further, the application discloses compounds and their preparation, use, pharmaceutical composition, and treatment.

Definitions

A = −CR_A=CR_a–;

E = −NR–, −O–, −S–, −S(=O)–, −S(=O)₂–, or −(S=O)(=NR_E)–;

ring Q = substituted or unsubstituted aryl or substituted or unsubstituted heteroaryl;

X = −O– or −S–;

Z = CR₂;

W = substituted or unsubstituted C₁–C₃ alkylene, substituted or unsubstituted C₁–C₂ heteroalkylene, substituted or unsubstituted C₂–C₃ alkenylene, substituted or unsubstituted C₃–C₈ cycloalkylene, or substituted or unsubstituted C₂–C₇ heterocycloalkylene;

R₁₁, R₁₂, R₁₃, R₁₄, R₁₆, and R₁₇ = H, D, F, −OR₁, substituted or unsubstituted C₁–C₄ alkyl, substituted or unsubstituted C₁–C₄ fluoroalkyl, and substituted or unsubstituted C₁–C₄ heteroalkyl;

R₁₅ and R₁₈ = H, D, F, −OR₁, substituted or unsubstituted C₁–C₄ alkyl, substituted or unsubstituted C₁–C₄ fluoroalkyl, and substituted or unsubstituted C₁–C₄ heteroalkyl; and

a = 0; b = 0; c = 1; and d = 1.

Key Structures

Biological Assay

The HTT quantitative splicing assay and mHTT protein potency assay were performed. The small molecule splicing modulators (compounds) described in this application were tested on GM04724 (CAG 70/20) Huntington’s disease patient lymphoblast cells. The HTT quantitative splicing assay EC₅₀ (nM) and HTT protein potency assay EC₅₀ (nM) values are shown in the following Table.

Biological Data

The Table below shows representative compounds (small molecules splicing modulators) (SMSMs) tested for HTT quantitative splicing potency and HTT protein potency. The biological data obtained from testing representative examples are listed in the following Table.

For EC₅₀: 0.01 nM ≤ A ≤ 15 nM; 16 nM ≤ B ≤ 50 nM; 51 nM ≤ C ≤ 100 nM; 101 nM ≤ D ≤ 500 nM; 501 nM ≤ E ≤ 10,000 nM.

Claims

Total claims: 73

Compound claims: 70

Pharmaceutical composition claims: 1

Method of treatment claims: 1

Use of compound claims: 1

Recent Review Articles

• 1.Alroy I.; Mansour W.; Klepfish M.; Sheinberger Y.. Drug Discovery Today 2021, 26, 786.
• 2.Angelbello A. J.; Chen J. L.; Disney M. D.. Ann. N. Y. Acad. Sci. 2020, 1471, 57.
• 3.Zhang D., Meng F.. ChemMedChem 2020, 15, 2098.
• 4.Zhu S.; Rooney S.; Michlewski G.. Int. J. Mol. Sci. 2020, 21, 2996.
• 5.Boer R. E.; Torrey Z. R.; Schneekloth J. S. Jr.. ACS Chem. Biol. 2020, 15, 808.
• 6.Costales M. G.; Childs-Disney J. L.; Haniff H. S.; Disney M. D.. J. Med. Chem. 2020, 63, 8880.

The author declares no competing financial interest.