Modified release orally administered amino acid formulations

A method of treating phenylketonuria comprising orally administering to a subject in need thereof, an effective amount of a modified release amino acid formulation, the formulation comprising a plurality of modified release granules and a plurality of tyrosine-containing granules, the modified release granules comprising:

• a) a sodium alginate binder admixed with an amino acid component, the amino acid component comprising at least 15 amino acids selected from the group consisting of L-alanine at 2.0 to 12.0 weight percent, L-arginine at 3.0 to 10.5 weight percent, L-aspartic acid at 5.0 to 10.5 weight percent, L-cystine at 1.5 to 4.0 weight percent, L-glutamine at 7.0 to 25.0 weight percent, glycine at 3.5 to 15.0 weight percent, L-histidine at 2.0 to 6.5 weight percent, L-isoleucine at 2.0 to 8.5 weight percent, L-leucine at 8.0 to 15.0 weight percent, L-lysine at 4.5 to 10.5 weight percent, L-methionine at 1.0 to 3.0 weight percent, L-proline at 3.5 to 15.0 weight percent, L-serine at 2.0 to 8.5 weight percent, L-threonine at 4.0 to 7.5 weight percent, L-tryptophan at 1.0 to 4.0 weight percent, L-valine at 2.5 to 10.0 weight percent, L-carnitine, L-glutamic acid, and taurine;
• and
• b) an ethylcellulose coating layer that coats the modified release granules;
• and
• wherein
• no more than 70% of the amino acids in the formulation are released after 30 minutes when the formulation is subjected to dissolution testing in a <711>USP 39 NF 34 paddle apparatus at 37° C. in 500 ml 0.1 N hydrochloric acid at a paddle speed of 50 rpm,
• further wherein
• the L-Tyrosine is present in the formulation from 2.5-14.0 weight %.