What are the different cures for PKU?

1. Diet

PKU is a treatable disease. Treatment involves a diet that is extremely low in phenylalanine, especially when the child is growing. The diet must be strictly followed. Research have shown that PKU patients who continue their diet into adulthood have better physical and mental health. 

For infants with PKU, there is a special formula called Lofenalac which can be used throughout life as a protein source that is extremely low in phenylalanine which is also balanced for other essential amino acids.

In a phenylalanine-free diet, long chain fatty acids are missing. By taking supplements such as fish oil, it may help to improve neurologic development, including fine motor coordination.Other specific supplements, such as iron or carnitine, may be needed.
Kimberly and Zieve. (2011) [3]

The diet for PKU consists of a milk substitute or formula such as Phenyl-Free 2* and measured amounts of fruits, vegetables, bread, pasta and cereals.

Many foods must be eliminated from a low phenylalanine diet. These foods are high protein foods such as milk and dairy products, meat, fish, chicken, eggs, beans and nuts which contain large amounts of phenylalanine. Eating these foods will cause high blood phenylalanine levels.

Phenyl-Free 2*, contains protein, vitamins, minerals and calories with no phenylalanine. With formula, a person with PKU gets plenty of protein and doesn't get the side effects of the high phenylalanine content of most foods. The phenylalanine-free formula is the most important part of the diet for PKU. Low protein breads and pastas is another important part of the diet. They are nearly free of phenylalanine, allow more food chioces, and provide energy and variety in the diet. 
The Cristine M. Trahms Program for Phenylketonuria. (2008) [4]

2. Kuvan


 Virginia E. Schuett, (2008)[5]

Kuvan is a drug. In some people with PKU, show signs of enhanced enzyme activity and lower blook phenylalanine levels after consuming the drug. 

Kuvan is a form of the cofactor for the phenylalanine hydroxylase enzyme, called tetrahydrobiopterin or BH4. When given in sufficiently large doses, it can cause whatever residual enzyme activity exists to work harder and thereby reducing blood phenylalanine levels. 

This drug will most likely be effective in patients with mild hyperphenylalaninemia. It is not possible to know in advance whether an individual with PKU will be responsive to the drug, so it must be tried for a length of time to determine if it will be effective. If it is effective, then a dosage requirement needs to be determined by the doctor. 

Currently, the use of Kuvan has resulted in greater tolerance for dietary phenylalanine while a strict diet is still maintained. 

3. Neutral amino acid therapy powder (bonus point) 

Mayo Clinic staff (2011) [12]

There is another way, which is to take a drug called neutral amino acid therapy powder. This drug will lessen the amount of phenylalanine absorbed, meaning you can eat more stuff with phenylalanine in it! That's got to be good news. However, due to the fact that nobody knows alot about this drug (like it's side effects and whether people can be allergic to it) therefore it might not be suitable for everyone. You have to ask the doctor whether you can use it or not.