Phenylketonuria is the most common inherited metabolic disease in France and is screened for neonatal exposure. Management consists of a strict and restrictive hypoproteic diet and the intake of amino acid substitutes and dietary supplements free of phenylalanine.One of the major difficulties, which is the source of many treatment failures, is the inappetence of the amino acid supplements required during a strict hypoproteic diet. New formulations, Glycomacropeptides (GMP), have recently appeared and are considered more palatable than conventional amino acid mixtures.

Phenylketonuria is the most common inherited metabolic disease in France and is screened for neonatal exposure. Management consists of a strict and restrictive hypoproteic diet and the intake of amino acid substitutes and dietary supplements free of phenylalanine. If the benefits of treatment are indisputable in children in terms of cognitive prognosis, this benefit is discussed once brain development is complete, especially as many adult patients are no longer treated. However, cognitive, neurological and reversible white matter disorders undergoing treatment are increasingly reported in adult phenylketonurics. As a result, recent European recommendations advocate the maintenance of life-long treatment. One of the major difficulties, which is the source of many treatment failures, is the inappetence of the amino acid supplements required during a strict hypoproteic diet. New formulations, Glycomacropeptides (GMP), have recently appeared and are considered more palatable than conventional mixtures.

PRIMARY OBJECTIVE:

Demonstrate a better metabolic balance under GMP treatment than a conventional amino acid mixture in adult phenylketonuric patients when resuming treatment.

Inclusion Criteria:

• Patient age ≥18 years on an empty stomach
• Phenylketonuric patient Patient with Phenylalaninemia ≥ 900μmol / L on a blotter performed during the screening period (or average of blotter results ≥900 μmol / L if several blotters performed during the screening period)
• Untreated or insufficiently treated patient: not taking or insufficiently Dietary foods for special medical purposes for his PKU, regardless of diet, at the discretion of the investigator
• Patient having signed a free, informed and express consent
• Patient requiring a diet restricted in natural proteins

Exclusion Criteria:

• Protected patient: court bail
• Patient with concomitant diseases / conditions that may compromise the study, at the discretion of the investigator
• Participated in a clinical trial or trial to evaluate PKU foods or treatments in the last 7 days prior to inclusion or planned during the next 6 months
• Participation in an interventional study with health products during the next 6 months
• Pregnancy project within 6 months, pre-conception diet, pregnancy or breastfeeding
• Refusal to consume only validated complements for the protocol
• Phenylketonuria undergoing treatment with BH4
• Allergy to the product under study