Treatment for cdkl5 deficiency disorder

The compound or composition for use according to any preceding claim, wherein the compound or composition comprises or further comprises a small molecule activator of CDKL2 expression or activity.

The compound or composition for use according to any preceding claim, wherein the compound or composition comprises or further comprises a polypeptide that increases CDKL2 expression.

The compound or composition for use according to any preceding claim wherein the compound or composition increases CDKL2 activity by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 100%, at least 150%, at least 200%, at least 250%, at least 300%, at least 350%, at least 400%, at least 450% or at least 500% relative to the CDKL2 activity measured in the absence of the compound or composition.

The compound or composition for use according to any preceding claim wherein the compound or composition increases CDKL2 expression by at least 10%, at least 20%, at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90% or at least 100%, at least 150%, at least 200%, at least 250%, at least 300%, at least 350%, at least 400%, at least 450% or at least 500% relative to the CDKL2 expression measured in the absence of the compound or composition.

The compound or composition for use according to any preceding claim further comprising a pharmaceutically acceptable carrier or excipient.

A compound or composition for increasing cyclin dependent kinase like 2 (CDKL2) expression or activity in the brain of a subject.

A recombinant adeno-associated virus (AAV) particle comprising an AAV capsid protein and a nucleic acid payload, wherein the nucleic acid payload encodes a polypeptide having at least 80%, at least 85%, at least 90%, at least 95% or at least 99% identity to a polypeptide of SEQ ID NO:

• 1, and wherein the recombinant AAV is capable of crossing the blood-brain barrier.

A recombinant adeno-associated virus (AAV) particle comprising an AAV capsid protein and a nucleic acid payload, wherein the nucleic acid payload encodes a polypeptide of SEQ ID NO:

• 1, and wherein the recombinant AAV is capable of crossing the blood-brain barrier.

A recombinant adeno-associated virus (AAV) particle comprising an AAV capsid protein and a nucleic acid payload, wherein the nucleic acid payload comprises a nucleotide sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 99% identity to a nucleotide sequence selected from the list consisting of SEQ ID NO:2 and SEQ ID NO:3, and wherein the recombinant AAV is capable of crossing the blood-brain barrier.

A recombinant adeno-associated virus (AAV) particle comprising an AAV capsid protein and a nucleic acid payload, wherein the nucleic acid payload comprises a nucleotide sequence selected from the list consisting of SEQ ID NO:2 and SEQ ID NO:3, and wherein the recombinant AAV is capable of crossing the blood-brain barrier.

A compound or composition for increasing cyclin dependent kinase like 2 (CDKL2) expression or activity, wherein the compound or composition is conjugated to a targeting agent.