Treatment of tauopathies

Abstract

The invention is directed to methods of treatment of Alzheimer's disease and other tauopathies, via the administration of antibodies having specificity to abnormal forms of tau protein, the antibodies showing no binding and / or reactivity to a normal tau protein and being administered under conditions and in amounts effective to prevent or treat Alzheimer's disease or other tauopathies. In certain embodiments, the antibodies are selective for soluble truncated tau protein truncated at (i) its C-terminus after the glutamic acid residue Glu391, or (ii) at the aspartic acid residue Asp421, or (iii) at its N-terminus at the aspartic acid residue Asp13, or (iv) a combination of (i)-(iii). Further aspects of the invention are directed to the administration of an immunogen comprising an abnormal tau, preferably a soluble truncated tau.

Description

BACKGROUND OF THE INVENTION[0001]Alzheimer's disease (AD) is a common chronic progressive neurodegenerative disease in which there is an irreversible loss of cognitive and behavioral functions. The disease can persevere for over 10 years, advancing from mild symptoms to extremely severe manifestations. AD is said to afflict approximately 10% of the population over the age of 65 and more than 30% of the population over the age of 80.[0002]Pathologically, Alzheimer's disease presents as extracellular amyloid plaques and intracellular neurofibrillary tangles. The neurofibrillary tangles are composed, e.g., of the microtubule-binding protein tau, which is assembled into paired helical and straight filaments. It has been suggested that these entities may be functionally linked, although the mechanisms by which amyloid deposition promotes pathological tau filament assembly is not clear.[0003]The common denominator of intracellular neurofibrillary structures (neurofibrillary tangles, dystr...

AI Technical Summary

Benefits of technology

[0021]It is a further object of the invention to provide antibodies capable of selectively recognizing a tau truncated at its C-terminus (e.g., at the glutamic acid residue Glu391 or at the aspartic acid residue Asp421) or its N-terminus (e.g., at amino acid Asp13) (e.g., tau1-13, tau14-441, tau14-391, tau391-414, tau1-391, tau1-421, tau14-421, tau14-410, tau391-410, tau14-412, tau391-412, tau 14-383, tau14-381, or tau 14-355, or a fragment of any of the foregoing). These antibodies would only recognize, bind or show reactivity with truncated tau, but will not recognize, bind or show reactivity with a normal tau protein (e.g., a full length untruncated htau40). In other words, these antibodies would recognize the neoepitope created by cleavage of tau (i.e., the amino acid sequences of the free N-terminus or the free C-terminus of the peptide created by cleavage of tau), but will not recognize the same sequence of amino acids present in the normal tau protein. These antibodies are therefore not expected to affect the biological functions of the normal tau protein, and, in the preferred embodiments, are expected to clear the peptides created by cleavage of tau and minimize or prevent the neurofiblary tangles formation. These antibodies may therefore be used in the treatment and / or prevention of AD and other tauopathies and in the preparation of pharmaceutical compositions (e.g., vaccines) for the treatment and prevention of these disorders.

[0022]It is an additional object of the invention to provide antibodies capable of selectively recognizing an abnormally phosphorylated truncated tau, preferably, tau1-13, tau 14-441, tau14-391, tau391-414, tau1-391, tau1-421, tau14-421, tau14-410, tau391-410, tau14-412, tau391-412, tau 14-383, tau14-381, or tau 14-355, or a fragment of any of the foregoing (e.g., tau phosphorylated at one or more of the following locations: Ser199, Ser202, Ser214, Ser235, Ser396, Ser404, Thr205, Thr231, and Thr212). These antibodies would only recognize, bind or show reactivity with the abnormally phosphorylated truncated tau, but will not recognize, bind or show reactivity with a normal tau protein (i.e., a full length untruncated htau40). In other words, these antibodies would recognize the neoepitope created by the cleavage and abnormal phosphorylation of tau, but would not recognize the same but not phosphorylated sequence of amino acids which is present internally in the normal tau protein. These antibodies are also not expected to affect the biological functions of the normal tau protein and / or inhibit caspase cleavage of tau, and, in the preferred embodiments, are expected to clear the peptides created by cleavage of tau and minimize or prevent the neurofiblary tangles formation, and are used to treat and / or prevent AD and other tauopathies.

[0028]Another aspect of the present invention includes a method of slowing progression of a tangle-related behavioral phenotype in a subject. This method includes administration to a subject in need of therapy for Alzheimer's disease or other tauopathies, of one or more antibodies with specificity to abnormal forms of tau protein (e.g., truncated tau) which are linear or conformationally different from normal tau, said antibodies showing no binding and / or reactivity with a normal tau protein. These antibodies are preferably specific for the neoepitope created by cleavage of tau and do not recognize the same sequence of amino acids present internally in the normal tau protein. These antibodies are therefore not expected to affect the biological functions of the normal tau protein, and, in the preferred embodiments, are expected to clear the peptides created by cleavage of tau and minimize or prevent the neurofiblary tangles formation. In certain preferred embodiments, the antibodies have specificity to a tau truncated at its C-terminus at the glutamic acid residue Glu391 or at the aspartic acid residue Asp421, and / or a tau truncated at its N-terminus at the aspartic acid residue Asp13 (e.g., tau1-13, tau 14-441, tau14-391, tau391-414, tau1-391, tau1-421, tau14-421, tau14-410, tau391-410, tau14-412, tau391-412, tau 14-383, tau14-381, or tau 14-355, or a fragment of any of the foregoing), and are administered under conditions and in an amount(s) effective to slow, inhibit and / or reverse a tangle-related behavioral phenotype in the subject.

[0029]In another aspect of the present invention, the antibodies administered selectively recognize a phosphorylated form of the abnormal tau protein (i.e., a truncated tau) and show no binding and / or reactivity with a normal tau protein. These antibodies are therefore not expected to affect the biological functions of the normal tau protein, and, in the preferred embodiments, are expected to clear the peptides created by cleavage of tau and minimize or prevent the neurofiblary tangles formation.

[0040]Another aspect of the present invention includes a method of slowing progression of a tangle-related behavioral phenotype in a subject. This method includes administration to a subject in need of therapy for Alzheimer's disease or other tauopathies, of a truncated tau protein, preferably a tau truncated at its C-terminus at glutamic acid residue Glu391 or at the aspartic acid residue Asp421, and / or a tau truncated at its N-terminus at the aspartic acid residue Asp13, under conditions and in the amounts to induce in situ production of free end-specific antibodies to the truncated protein(s) and effective to slow, inhibit and / or reverse a tangle-related behavioral phenotype in a subject.

[0052]“Antibody” as used herein is meant to include intact molecules and fragments thereof, as well as synthetic and biological derivatives thereof, such as for example Fab, F(ab′2 an F1, fragments-free or expressed, e.g., on the surface of filamentous phage on pIII or pVIII or other surface proteins, or on the surface of bacteria, which are capable of binding an antigen. Fab, F(ab′2 and FV fragments lack the FC fragments of intact antibody, clear more rapidly from the circulation and may have less non-specific tissue binding of antibody. Furthermore FV antibody (often called as minibody) can be easily engineered to carry on its C-terminus specific tracer and used for early intravital presymptomatic diagnosis of AD, since stage I, II and III of AD that is recognized by the antibodies according to the present invention is not associated with intellectual decline. The term antibody encompasses, e.g., chimeric and humanized antibodies. The antibody may be a monoclonal antibody or a polyclonal antibody. It also encompasses recombinant antibodies. The antibodies may preferably be linear antibodies, or conformational antibodies.

Problems solved by technology

Therefore, the aggregation of tau protein in AD is highly suspicious.

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