Insight into pku sphere

Insight into PKU sphere. A GMP-based protein substitute.

Results from UK surveys of teens and adults with phenylketonuria and their dietitians

^{Wilson R. Insight into PKU sphere®, a GMP-based protein substitute, Complete Nutrition. 2021. Vol. 21 No. 1 Feb/March PP31-33.}

Vitaﬂo launched PKU sphere in 2017 in the UK, by 2019 PKU sphere had launched globally and there were more than 300 people in the UK alone using PKU sphere. Many individuals with PKU and their dietitians shared informal feedback that PKU sphere particularly met the needs of teens and adults with difficulty adhering to their protein substitutes.

Vitaﬂo conducted online surveys with the objective of understanding the impact of PKU sphere on dietary adherence from the perspective of individuals with PKU and their dietitians.

UK metabolic dietitians, managing individuals over 13 years of age consuming PKU sphere, were contacted via the British Inherited Metabolic Disease Group. Participating dietitians chose if they also distributed a separate survey to eligible individuals on their caseload. Individuals with PKU were also made aware of the survey via a Facebook post.

Survey Eligibility for individuals with PKU:

Individuals with PKU and their dietitians reported that PKU sphere offers sensory advantages compared to amino acid-based protein substitutes, including improved taste, aftertaste and smell. Individuals with PKU reported improved breath malodour and GI symptoms when taking PKU sphere and stated its taste, low volume, looking similar to a protein shake and provision of a sports shaker were advantages over amino acid-based protein substitutes.

Most dietitians and individuals with PKU surveyed, agreed that these attributes can promote adherence to protein substitutes, which may in-turn support improved clinical outcomes.

Responses from the dietitians

19 dietitians took part in the online survey

95% ⁽ⁿ⁼¹⁸⁾ reported that prior to the availability of GMP-based protein substitutes they had experienced cases in which they had exhausted all amino acid-based protein substitute options.

Advantages of GMP-based compared to amino acid-based protein substitutes most commonly selected were:

Improved taste

Improved after taste

Improved Smell

PKU sphere had a positive impact on adherence

• • When asked about individuals who switched to PKU sphere 84% ⁽ⁿ⁼¹⁶⁾ stated adherence to protein substitutes improved.

• None reported that adherence deteriorated with PKU sphere.

• Advantages of PKU sphere selected by dietitians included:

- sensory properties 84% ^{(n = 16)}

- low energy content 74%, ^{(n = 14)}

- provision of docosahexaenoic acid (DHA) 58% ^{(n = 11)}

- its low volume 69% ^{(n = 13)}

• 42% ^{(n = 8)} stated that the powdered format was a disadvantage.

“PKU sphere offers a great low calorie, low sugar, low volume supplement. I believe it has greatly helped compliance to the PKU diet and in turn improved Phe levels, without having to always change exchanges.” - Comment from Dietitian

In your experience, when a patient changes from another product to PKU sphere does blood phe control:
	% of responders
Improve	42 ⁽ⁿ⁼⁸⁾
Remain the same	16 ⁽ⁿ⁼³⁾
Worsen	5 ⁽ⁿ⁼¹⁾
Unknown	32 ⁽ⁿ⁼⁶⁾
Incomplete data	5 ⁽ⁿ⁼¹⁾

“…if a patient has good control already, their Phe tends to increase slightly but if they have poor control, their control seems to improve due to increased palatability hence improved compliance. ” - Comment from Dietitian

Responses from individuals with PKU

36 responses were collected in total

86% ⁽ⁿ⁼³¹⁾ of individuals with PKU were > 18 years old.

The majority had been taken PKU sphere long term with 89% ⁽ⁿ⁼³²⁾ taking it for at least a year and most took PKU sphere as their sole source of protein substitute ⁽ⁿ⁼²⁸⁾ .

• 22% ⁽ⁿ⁼⁸⁾ took PKU sphere in combination with an AA-based PS, of these 75% opted for a liquid product to take alongside PKU sphere.

PKU sphere was preferred over their previous protein substitute.

• 34 respondents reported taking an amino-acid based protein substitute, the remaining 2 individuals were not taking any protein substitute prior to PKU sphere.

• 92% ^{(n = 33)} stated that the taste of PKU sphere was better than their previous protein substitute.

“I was going back on diet and sampled a number of options. PKU sphere was the best tasting.” - Comment from Individual with PKU.

“The ﬂavours are much more tasteful without the bitterness usually associated with amino acid-based supplements.” - Comment from Individual with PKU.

PKU sphere compared more favourably to amino acid-based protein substitutes in every category.

• 58% ⁽ⁿ⁼²¹⁾ reported PKU sphere improved their ability to adhere to the PKU diet.

• 91% ⁽ⁿ⁼³¹⁾ stated physical properties of PKU sphere supported adherence, including being supplied with a sports shaker, easy to transport and low in volume

Percentage of individuals who selected reasons which enabled them to consume their protein substitute

Why are you able to take your protein substitute regularly every day?	Amino acid-based protein substitutes ⁽ⁿ⁼³⁶⁾	PKU sphere ^(n=34**)
Like the taste	8 ⁽ⁿ⁼³⁾	79 ⁽ⁿ⁼²⁷⁾
Like the smell	3 ⁽ⁿ⁼¹⁾	42 ⁽ⁿ⁼¹⁴⁾
Like the ﬂavour options	11 ⁽ⁿ⁼²⁾	50 ⁽ⁿ⁼¹⁷⁾
Low in calories	17 ⁽ⁿ⁼⁶⁾	35 ⁽ⁿ⁼¹²⁾
Low sugar content	6 ⁽ⁿ⁼²⁾	21 ⁽ⁿ⁼⁷⁾
Low volume	14 ⁽ⁿ⁼⁵⁾	56 ⁽ⁿ⁼¹⁹⁾
Easy to transport	42 ⁽ⁿ⁼¹⁵⁾	59 ⁽ⁿ⁼²⁰⁾
Appearance similar to normal protein shakes/less self-conscious	0	47 ⁽ⁿ⁼¹⁶⁾
Preparation options and recipes	3 ⁽ⁿ⁼¹⁾	21 ⁽ⁿ⁼⁷⁾
No stomach upset	3 ⁽ⁿ⁼¹⁾	53 ⁽ⁿ⁼¹⁸⁾
Less breathe odour	0	47 ⁽ⁿ⁼¹⁶⁾

^{**Survey participants were only prompted to answer this question if reported they were able to take PKU sphere every day.}

PKU sphere had a positive impact on adherence

• PKU sphere enabled an increased level of adherence compared to amino acid-based protein substitute for 33% ⁽ⁿ⁼¹²⁾ of respondents

• The reasons stated for poor adherence to amino acid-based protein substitutes were:

- Poor sensory properties.

- GI symptoms.

- Breath malodour.

Reported degree of adherence to recommended amount of protein substitute

Individuals with lowest adherence to amino acid-based protein substitute reported that they had been able to be more adherent to PKU sphere over a sustained period.

• 16 individuals with PKU were classiﬁed as non-adherent to amino acid-based protein substitutes (taking 80% or less of their recommended amount). 11 of these 16 individuals had been taking PKU sphere long term, for more than a year.

• All 16 reported the taste of PKU sphere to be better than amino acid-based protein substitutes.

• 12 said PKU sphere had improved their ability to adhere to the PKU diet.

A more comprehensive write up of this survey can be found here

Animations that share this information in a patient friendly format can be found here on the PKU sphere section of the Vitafriends PKU website.

^{PKU sphere is a Food for Special Medical Purposes. For use under medical supervision from 4 years of age.}