Abstract: The present invention provides a method of PEGylating a human truncated cystathionine ?-synthase protein containing a mutation of a cysteine to a serine at amino acid position 15 (htCBS C15S). The htCBS C15S was PEGylated with one of 5 kDa, 10 kDa, or 20 kDa NHS ester PEG molecules. In-process monitoring of the PEGylation process was used in the method to reduce levels of unPEGylated htCBS C15S and htCBS C15S with insufficient PEGylation. Administration of the PEGylated htCBS C15S had efficacy throughout the course of treatment for homocystinuria.

Abstract: The present disclosure provides methods for treating homocystinuria or elevated homocysteine levels in subjects, including methods of improving cognitive function and ameliorating skeletal fragility, and methods of stratifying patient populations to determine disease progression or severity and/or to determine treatment regimens. In some embodiments, the methods of improving cognitive function in a subject having elevated total plasma homocysteine (tHcy) levels further comprise providing a cognitive or behavioral intervention.

Abstract: The present disclosure provides formulations for a drug product comprising a PEGylated CBS protein having the amino acid sequence of SEQ ID NO: 1. Dosages and dosing regimens are provided for treatment of homocystinuria in a subject in need thereof. Additionally, the dosages and dosing regimens are also provided to reduce the level of homocysteine (Hcy) or increase the levels of cysteine (Cys) and/or cystathionine (Cth) in a subject in need thereof.

Abstract: The present invention provides a method of PEGylating a human truncated cystathionine ?-synthase protein containing a mutation of a cysteine to a serine at amino acid position 15 (htCBS C15S). The htCBS C15S was PEGylated with one of 5 kDa, 10 kDa, or 20 kDa NHS ester PEG molecules. In-process monitoring of the PEGylation process was used in the method to reduce levels of unPEGylated htCBS C15S and htCBS C15S with insufficient PEGylation. Administration of the PEGylated htCBS C15S had efficacy throughout the course of treatment for homocystinuria.

Abstract: The present invention provides a method of PEGylating a human truncated cystathionine ?-synthase protein containing a mutation of a cysteine to a serine at amino acid position 15 (htCBS C15S). The htCBS C15S was PEGylated with one of 5 kDa, 10 kDa, or 20 kDa NHS ester PEG molecules. In-process monitoring of the PEGylation process was used in the method to reduce levels of unPEGylated htCBS C15S and htCBS C15S with insufficient PEGylation. Administration of the PEGylated htCBS C15S had efficacy throughout the course of treatment for homocystinuria.