Over the last decade, we have answered hundreds if not thousands of questions about Glytactin, Glycomacropeptide (GMP), Amino Acid products, and transition strategies. These FAQs are intended to be supplemental reference material and are intended solely for the general information of the reader. They are not intended to diagnose health problems or to take the place of professional medical care. Always consult with your health care provider. If you cannot find the answer to your question, we ask that you please contact us.

Phenylketonuria is a rare genetic disorder which affects approximately 1 in every 10,000-15,000 births and it is highest amongst Caucasians.[4] Diagnosis of PKU is usually shortly after birth through the newborn screening process. The disease is caused by a mutation in the gene that produces the enzyme phenylalanine hydroxylase. The enzyme is needed to breakdown the essential amino acid Phenylalanine (Phe), which is found in protein-based foods and some artificial sweeteners. Without proper management, phenylalanine increases to harmful levels in the blood.[4]
PKU varies in severity from benign 
or mild PKU, with limited signs and symptoms, to what is known as classical PKU, which is likely to result in the development of serious disability and a variety of additional health problems if left untreated. Classical PKU is caused by nearly absent or completely absent activity of the enzyme phenylalanine hydroxylase (<5% compared to normal levels). This enzyme is required for the normal breakdown of Phe, and its limited activity in PKU patients causes the unhealthy build-up of Phe.[5] Poor management of PKU can result in both physical and neurological developmental delay. If PKU remains untreated for a prolonged period, patients can progress to severe intellectual disabilities. Patients who are non-adherent to dietary management at early ages are more susceptible to Attention Deficit and Hyperactivity Disorder (ADHD), seizure disorders, and a number of other mental health conditions. Other significant long-term complications include bone mineral disease, Vitamin B12 deficiency, and impaired growth.[6-9]

A Phe restricted diet paired with Phe free amino acid supplementation remains the gold standard for the management of PKU.[6] The diet and supplementation is dependent on the severity of the disorder and nutritional need. Those with mild forms of PKU may be able to manage the condition with little to no alterations to their diet. Those with mild, moderate, or severe disorders require diets that significantly limit the consumption of products containing phenylalanine, particularly high protein foods.[6]

Instead, PKU patients must rely on low Phe containing cereals, starches, fruits, and vegetables, along with protein substitutes to meet all nutritional requirements. These foods are allowed in quantities that suit the individual’s tolerance for Phe and each individual’s diet is determined with the help of their healthcare providers. Such restrictive diets make it impossible for individuals to obtain the necessary daily nutrition through diet alone.[10]

In order to ensure nutritional requirements are met,  supplements are incorporated into the diet. These products become a critical component of most PKU patients’ daily diet.[6] Adherence to the diet and supplements is crucial for managing the disorder; however, most diets are very difficult for patients and their families to follow.[10] In addition, many of the standard  amino acid supplements have historically been troubled by poor taste, smell and demanding consumption schedules.[5] Following these restrictive diets has been shown to have significant psychosocial burden and can result in lowered quality of life.

As previously mentioned, patients diagnosed with PKU must adhere to a very strict diet which significantly limits the foods they are able to eat. In addition, patients must also supplement this diet with products that provide the necessary amino acids multiple times throughout each day. Patients are typically started on the restricted diet and supplementation at a very early age and must follow the diet throughout their life. In addition, patients must have their Phe levels monitored regularly to ensure blood levels are within the recommended values.

Adherence to the diet alone is problematic for most patients, and the added need to consume supplements several times each day makes complete adherence very difficult. Adherence to low Phe protein supplements is further complicated by the poor taste and smell of many of the available products. Inclusion of protein substitutes, which are more palatable and offer a variety of formulations, has the potential to significantly impact individual adherence and prevent further complications from the disease.

Products available to supplement PKU patients managing the disorder through diet restrictions have historically been composed primarily of synthetic essential amino acid formulations. It is often a challenge for patients to adhere to diets supplemented strictly with amino acid-based formulas due in part to poor taste and smell, as well as, an inability of these formulas to encourage satiety. 

Glytactin differs from those products through its inclusion of both a formula of essential large neutral amino acids (LNAAs) and glycomacropeptide (GMP), which is the only naturally occurring, low-phenylalanine whole protein. Production of GMP is accomplished through a process similar to that used in cheese making.[1] GMP is one of several proteins, which make up whey and can be isolated during manufacture. The isolated GMP is then incorporated into the Glytactin line of products. 

The essential amino acid and GMP formulation found in Glytactin offers a variety of patient benefits. First, the formulation helps to stabilise Phe levels throughout the day, eliminating the spikes and troughs seen with alternative PKU preparations.[14] This leads to increased energy levels and improved concentration. Second, it reduces the Phe absorption across the blood brain barrier through its use of LNAAs, reducing the risk of disease progression.[15] Third, it returns the level of the hunger hormone, grehlin, closer to that seen in individuals on a normal diet.[16] This helps patients feel full longer, which improves the overall experience of PKU patients.

In addition, many patients believe Glytactin products have a more appealing taste, smell, and appearance than other products currently available.[17] The available product line includes a powder that makes a flavoured milk-like substitute and a pre-made milk like drink. In addition, each formulation is made up of 10 or 15 grams of protein, making it easy for patients to tailor their supplements to their and personal preferences

Kosher

 

Do you have questions about kosher certification or kosher medical foods (formula) or are you simply looking for a source for answers to the most frequently asked questions about kosher certification or kosher medical foods (formula)?

These FAQs are intended to be supplemental reference material and are intended solely for the general information of the reader. They are not intended to diagnose health problems or to take the place of professional medical care. Always consult with your health care provider. If you cannot find the answer to your question, we ask that you contact us.

To be certified kosher, all ingredients in every product, and the process of preparing the product, must be certified for orthodox kosher-compliance.

  • Comply with a strict policy of kosher food laws, including cleanliness, purity and quality.
  • Kosher refers to a set of intricate religious laws that detail the types of food that a person may eat and the ways in which it may be prepared.
  • Kosher iconThe OU-D symbol on products indicates that their kosher status is being independently monitored by the staff of the Orthodox Union’s Kashruth Division.
  • This symbol is recognized by the kosher consumer as the sign that our products meet the strictest standards of kosher.

At Cambrooke, our vision is to make products suitable for all people who have health conditions that require medical foods.

Where an ingredient was not approved by the Orthodox Union, we switched to an approved kosher version of the same ingredient. These changes did not impact the nutritional value of the products.

  • OU-D ranked higher than all other certifications on attributes such as “Most reliable”, “Most Respected”, and “Most Personally Trusted” in a survey of consumers.
  • Orthodox Union’s Kashruth Division certifies more than twice as many products on supermarket shelves than all of its competitors combined.

Currently, these liquid formulas are OU-D kosher certified:

  • PKU
    • Glytactin RTD

Powder medical foods will be kosher approved within 12 months.

Yes, if a kosher version of an amino acid is available at Ajinomoto then we are procuring it, since Ajinomoto has the highest quality amino acids available in the market.

BetterMilk

Yes. BetterMilk is a formula designed to provide an easily absorbed protein source for PKU patients and has been fortified with essential amino acids, vitamins, and minerals.

Once prepared, BetterMilk should be consumed entirely. However, prepared BetterMilk can be refrigerated for up to 24 hours. Unopened product packets have a one year recommended use by date.

To prepare, mix one packet of BetterMilk with four ounces (120mL) of cold water or more/less to taste. BetterMilk can also be incorporated into recipes.

Glytactin RTD 10 (10g of Protein Equivalent (PE))

Yes. Glytactin RTD 10, a convenient ready-to-drink formula, is designed to provide PKU patients with an easily absorbed protein source that is fortified with essential amino acids, vitamins, and minerals.

Unopened Glytactin RTD 10 has a one year recommended use by date.

Store Glytactin RTD 10 in a cool, dry place and refrigerate after opening. Ideal temperature for storing is 15-25°C.

No preparation for Glytactin RTD 10 is required. Glytactin RTD 10 comes in a convenient ready-to-drink format. Simply shake the carton, peel open the foil seal from the bottom or pop in the straw and enjoy.

Glytactin RTD 15 (15g of Protein Equivalent (PE))

Yes. Glytactin RTD 15, a convenient ready-to-drink formula, is designed to provide PKU patients with an easily absorbed protein source that is fortified with essential amino acids, vitamins, and minerals.

Unopened Glytactin RTD 15 has a one year recommended use by date.

Store Glytactin RTD 15 in a cool, dry place and refrigerate after opening. Ideal temperature for storing is 15-25°C.

No preparation for Glytactin RTD 15 is required. Glytactin RTD 15 comes in a convenient ready-to-drink format. Simply shake the carton, peel open the foil seal from the bottom or pop in the straw and enjoy.

How do I Order?

Glytactin RTD and Glytactin BetterMilk are available on prescription from your GP.

HealthNet Homecare is our U.K. supplier and delivers to the whole of the U.K. using the parcel delivery company DPD.

Delivery can either be made to a private address or to a community pharmacy.

To place an order simply call the Customer Service Team on 0113 201 5757 or post the prescription to ‘Freepost HealthNet’, once this has been processed you will be contacted to arrange a convenient delivery date and time.

Download the Healthnet home delivery order form

Download the Healthnet home delivery registration form

Sources

1. Etzel MR. Manufacture and use of dairy protein fractions. J Nutr 2004; 134:996S-1002S.
2. Lim K, van Calcar SC, Nelson KL, Gleason ST, Ney DM. Acceptable low-phenylalanine foods and beverages can be made from glycomacropeptide from cheese whey for individuals with PKU. Mol Genet Metab 2007;92:176–8.
3. Van Calcar SC, MacLeod EL, Gleason ST, et al. Improved nutritional management of phenylketonuria by using a diet containing glycomacropeptide compared with amino acids. Am J Clin Nutr. 2009; 89(4):1068–1077.
4. Medicine, U.S.N.L.o. Phenylketonuria: MedlinePlus Medical Encyclopedia. 2013 10/10/2013]; Available from: http://www.nlm.nih.gov/medlineplus/ency/article/001166.htm.
5. National PKU Alliance. 2011 10/10/2013]; Available from: http://www.npkua.org/index.php/pku-facts.
6. NIH Consensus Statement Program: Phenylketonuria: Screening and Management. 2000 10/10/2013]; Available from: http://consensus.nih.gov/2000/2000phenylketonuria113html.htm.
7. Bilder, D.A., et al., Psychiatric symptoms in adults with phenylketonuria. Molecular Genetics and Metabolism, 2013. 108(3): p. 155-160.
8. Sharman, R., et al., Depressive symptoms in adolescents with early and continuously treated phenylketonuria: Associations with phenylalanine and tyrosine levels. Gene, 2012. 504(2): p. 288-291.
9. Walter, J.H., Vitamin B-12 deficiency and phenylketonuria. Molecular Genetics and Metabolism, 2011. 104: p. S52-S54.
10. Giovannini, M., et al., Phenylketonuria: Dietary and therapeutic challenges. Journal of Inherited Metabolic Disease, 2007. 30(2): p. 145-152.
11. Administration, U.S.F.a.D., FDA Approves Kuvan for Treatment of Phenylketonuria (PKU), 2007.
12. Health, N.I.o. What are the common treatments of PKU? 2012 11/30/2012 [cited 2013 10/10/2013]; Available from: http://www.nichd.nih.gov/health/topics/pku/conditioninfo/Pages/treatments.aspx.
13. Draft Guidance: Frequently Asked Questions About Medical Foods, F.a.D. Administration, Editor 2013.
14. Ney, D.M., et al., Nutritional management of PKU with glycomacropeptide from cheese whey. Journal of Inherited Metabolic Disease, 2009. 32(1): p. 32-39.
15. Van Calcar, S.C., et al., Dietary glycomacropeptide (GMP) supports growth and reduces the concentrations of phenylalanine in plasma and brain in the PKU mouse. Molecular Genetics and Metabolism, 2008. 93(3): p. 263-263.
16. MacLeod, E.L., et al., Breakfast with glycomacropeptide compared with amino acids suppresses plasma ghrelin levels in individuals with phenylketonuria. Molecular Genetics and Metabolism, 2010. 100(4): p. 303-308.
17. Van Calcar, S.C. and D.M. Ney, Food Products Made with Glycomacropeptide, a Low-Phenylalanine Whey Protein, Provide a New Alternative to Amino Acid-Based Medical Foods for Nutrition Management of Phenylketonuria. Journal of the Academy of Nutrition and Dietetics, 2012. 112(8): p. 1201-1210.