Oligonucleotide comprising an inosine for treating dmd

Abstract

The invention provides an oligonucleotide comprising an inosine, and / or a nucleotide containing a base able to form a wobble base pair or a functional equivalent thereof, wherein the oligonucleotide, or a functional equivalent thereof, comprises a sequence which is complementary to at least part of a dystrophin pre-m RNA exon or at least part of a non-exon region of a dystrophin pre-m RNA said part being a contiguous stretch comprising at least 8 nucleotides. The invention further provides the use of said oligonucleotide for preventing or treating DMD or BMD.

Description

FIELD OF THE INVENTION[0001]The invention relates to the fields of molecular biology and medicine.BACKGROUND OF THE INVENTION[0002]A muscle disorder is a disease that usually has a significant impact on the life of an individual. A muscle disorder can have either a genetic cause or a non-genetic cause. An important group of muscle diseases with a genetic cause are Becker Muscular Dystrophy (BMD) and Duchenne Muscular Dystrophy (DMD). These disorders are caused by defects in a gene for a muscle protein.[0003]Becker Muscular Dystrophy and Duchenne Muscular Dystrophy are genetic muscular dystrophies with a relatively high incidence. In both Duchenne and Becker muscular dystrophy the muscle protein dystrophin is affected. In Duchenne dystrophin is absent, whereas in Becker some dystrophin is present but its production is most often not sufficient and / or the dystrophin present is abnormally formed. Both diseases are associated with recessive X-linked inheritance. DMD results from a frame...

AI Technical Summary

Benefits of technology

[0012]A third advantage of using an inosine and / or a base able to form a wobble base pair in an oligonucleotide of the invention is to avoid or decrease a potential multimerisation or aggregation of oligonucleotides. It is for example known that an oligonucleotide comprising a G-quartet motif has the tendency to form a quadruplex, a multimer or aggregate formed by the Hoogsteen base-pairing of four single-stranded oligonucleotides (reference 61), which is of course not desired: as a result the efficiency of the oligonucleotide is expected to be decreased. Multimerisation or aggregation is preferably assessed by standard polyacrylamid non-denaturing gel electrophoresis techniques known to the skilled person. In a preferred embodiment, less than 20% or 15%, 10%, 7%, 5% or less of a total amount of an oligonucleotide of the invention has the capacity to multimerize or aggregate assessed using the assay mentioned above.

[0133]In another preferred embodiment, a composition further comprises an angiotensin-converting enzyme (ACE) inhibitor, preferably perindopril. ACE inhibitors are capable of lowering blood pressure. Early initiation of treatment with perindopril is associated with a lower mortality in DMD patients22. A composition further comprising an ACE inhibitor, preferably perindopril for use as a medicament is also provided. Said medicament is preferably for alleviating one or more symptom(s) of DMD. In one embodiment, said composition is used in order to alleviate one or more symptom(s) of a severe form of BMD wherein a very short dystrophin protein is formed which is not sufficiently functional. The usual doses of an ACE inhibitor, preferably perindopril are about 2 to 4 mg / day22. In a more preferred embodiment, an ACE inhibitor is combined with at least one of the previously identified adjunct compounds.

Problems solved by technology

In Duchenne dystrophin is absent, whereas in Becker some dystrophin is present but its production is most often not sufficient and / or the dystrophin present is abnormally formed.

The frameshift in the DMD gene's transcript (mRNA) results in the production of a truncated non-functional dystrophin protein, resulting in progressive muscle wasting and weakness.

In the absence of dystrophin, mechanical stress leads to sarcolemmal ruptures, causing an uncontrolled influx of calcium into the muscle fiber interior, thereby triggering calcium-activated proteases and fiber necrosis.

For most genetic muscular dystrophies no clinically applicable and effective therapies are currently available.

Hence, exon skipping techniques applied on the dystrophin gene result in the generation of at least partially functional—albeit shorter—dystrophin protein in DMD patients.

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