Study ID

Methods

Participants

Interventions

Outcomes

Notes

Cleary 2003

RCT.

Investigating 5 adults with PKU on a normal diet using MRS of brain. Entrants had classical PKU diagnosed and treated in the newborn period, at the time of study aged between 22‐37 years.

Treatment group were given a mixture of large neutral amino acids at a dose of 0.81 g amino acids per kg or a similar tasting placebo .This was given over 24 hours in 5 divided doses. MRS was performed at 5 intervals during the 24‐hour period. Participants crossed over after 1 week.

This study has not yet been published in full as author of abstract does not have ownership of the data. Author has agreed to attempt to pursue publication after having been approached by the review authors.

MacDonald 2003

RCT. Cross‐over design.

16 children with PKU.

Initially only 13 participants were entered into the trial and randomised into 3 groups. Intervention was by administering protein substitute at different times and in different doses. Protocol A: protein substitute was administered in 3 equal doses over 10 hours during the day; Protocol B: protein substitute was administered in 3 equal divided doses over a 14‐hour period; Protocol C: protein substitute was administered in 4 equal divided doses over 14‐hour period. Because of interim analysis results, a further 3 participants were entered into the trial. At this stage a new group was introduced ‐ Protocol D and these 3 participants were entered into protocol A, B and D. Protocol D: protein substitute administered in 6 equal divided doses over a 24‐hour period. As 3 participants were introduced after the initial randomisation phase their results cannot be included in the review. At the present time only information from group C can be used as the extra participants did not enter this group.

Individual patient data have been sought from the author. This would enable the 3 extra participants to be identified within groups A and B and D and excluded from the analysis.

Footnotes ‐ MRS: magnetic resonance spectroscopy; PKU: phenylketonuria; RCT: randomised controlled trial