Finally, the wait is over…

The 1st PKU formula with GMP providing 20 g protein equivalent in ONLY 8 fl oz

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The primary medical management for PKU is a low protein diet and formula for life.1-3

Lifelong restrictive diets become harder to follow with age – 2/3 of US teens and adults struggle to stay on diet and drink their formula1

Although the PKU diet can be hard and overwhelming, drinking PKU sphere liquid is not.

Vanilla flavor

8 fl oz (237 ml) bottle

Suitable from 1 year of age

PKU sphere liquid is designed with 3 core features to make it easier4 to take your formula everyday:

  1. Taste: Contains GMP from a natural whole protein source
    • Offering a different taste to amino acid based formulas preferred by some individuals with PKU5-8
  2. Convenience: Resealable bottle
    • Easy to take on-the-go to daycare, school, work or when traveling.
  3. Low volume: Provides 20 g PE in one 8 fl oz bottle
    • To help achieve daily protein intake goals

Tasting is Believing

Taste for Yourself

PKU sphere liquid is the lowest volume*
ready-to-drink formula with GMP

  • Product 1: Glytactin^ RTD 15
  • Product 2: Glytactin RTD Lite 15
  • Product 3: Phenylade^^ GMP Ready
  • Product 4: Glytactin RTD 10
  • Product 5: Glytactin Restore 10
  • Product 6: Glytactin Restore Lite 10
Volume information on the graph above is available as of the date of publication and is subject to change.

*Per g protein equivalent, among ready-to-drink GMP based formulas for PKU.

^Glytactin is a trademark of Ajinomoto Cambrooke, Inc. ^^Phenylade is a registered trademark of Nutricia North America, Inc.


1) Jurecki ER, et al. Adherence to clinic recommendations among patients with phenylketonuria in the United States. Mol Gen Metab. 2017;120:190–197.

2) Singh RH, Cunningham AC, Mofidi S, Douglas TD, Frazier DM, Hook DG, et al. Updated, web-based nutrition management guideline for PKU: An Evidence and consensus based approach. Mol Gen Metab. 2016; 118(2):72–83.

3) MacDonald A, Gokmen-Ozel H, van Rijn M, Burgard P. The reality of dietary compliance in the management of phenylketonuria. J Inherit Metab Dis. 2010; 33(6):665–70.

4) MacDonald, A et al. ‘Ready to drink’ protein substitute is easier is for people with phenylketonuria. J Inherit Metab Dis. 2006; 29(4):526–31.

5) Lim K, et al. Acceptable low-phenylalanine foods and beverages can be made with glycomacropeptide from cheeses whey for individuals with PKU. Mol Gen Metab. 2007; 31:92(1):176–8.

6) Van Calcar SC, et al. Improved nutritional management of Phenylketonuria by using a diet containing glycomacropeptide compared with amino-acids. Am J Clin Nutr. 2009; 89(4):1068–77.

7) Ney, D. Glycomacropeptide for nutritional management of phenylketonuria: a randomized, controlled, crossover trial. Am J Clin Nutr. 2016; 104(2):334–45.

8) Proserpio C, et al. Exploring Drivers of Liking of Low-Phenylalanine Products in Subjects with Phenylketonuria Using Check-All-That-Apply Method. Nutrients. 2018; 10(9):1179.

Tasting is Believing!

Be one of the first to try the new PKU sphere liquid.

Request your sample and it will be shipped directly to your home.

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PKU sphere liquid is a low phenylalanine (Phe) ready-to-drink glycomacropeptide (GMP) based formula. For use in the dietary management of Phenylketonuria (PKU). Suitable from 1 year of age.

USE UNDER MEDICAL SUPERVISION. Not for intravenous use. For enteral use only. Not for use as a sole source of nutrition. The content on this website is for educational purposes only and should not be considered to be medical advice. It is not intended to replace the advice of your healthcare team. Consult your healthcare team to determine which products are appropriate before making any changes to your diet.