Phenylketonurias
Conditions
Brief summary
Conduct a prospective, longitudinal study to evaluate nutritional status in adults with phenylketonuria (PKU) before and during treatment with pegvaliase (Palynziq™).
Detailed description
The investigators will compare intra-subject change in adults with PKU who follow a protein-restricted diet (protein intake less than the RDA for protein based on weight (0.8 g/kg/day) with or without a PKU medical food) within 90 days of starting pegvaliase (baseline) and 9 and 15 months later. The investigators will collect laboratory measures of nutrition status, anthropometrics, Dual-Energy X-Ray Absorptiometry (DXA) to measure body composition and bone mineral density (BMD), and indirect calorimetry to measure resting energy expenditure (REE). In addition, three-day food records will be obtained to assess protein intake and overall diet quality.
Interventions
None listed
Sponsors
Boston Children's Hospital
BioMarin Pharmaceutical
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* Diagnosis of phenylketonuria * Aged 18-65 years * Following a protein-restricted diet with or without medical food within the last 30 days * Routine natural protein intake from food is less than the RDA for protein based on weight (0.8 g/kg/day). * If not consuming animal proteins, recommended protein intake is 115% RDA due to lower bioavailability of plant proteins. * Within ±90 days of starting treatment with pegvaliase at time of study enrollment
Exclusion criteria
* Unable to consent to study * Under age 18 or over age 65 years * Routine natural protein intake is greater than the RDA for protein (0.8 g/kg/d) within the last 30 days. * Females who are currently pregnant or lactating
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Intra-subject change in intact and medical food protein intake (grams/day) as reported on three-day food records at months 0, 9, and 15. | 15 months |
| Intra-subject change in serum markers of protein status at months 0, 9, and 15. | 15 months |
| Intra-subject difference in lean body mass (%LBM) from month 0 to 15. | 15 months |
| Intra-subject difference in bone mineral density from month 0 to 15. | 15 months |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intra-subject change in concentrations of serum markers of micronutrient status at months 0, 9, and 15. | 15 months | — |
| Intra-subject change in serum concentrations of essential fatty acid nutriture at months 0, 9, and 15. | 15 months | — |
| Intra-subject change in BMI at months 0, 9, and 15. | 15 months | — |
| Intra-subject change in serum markers of cardiovascular status at months 0, 9, and 15. | 15 months | — |
| Intra-subject change in emotional eating, cognitive restraint, uncontrolled eating at months 0, 9, and 15. | 15 months | Three-Factor Eating Questionnaire (TFEQ)-18 is an 18-item questionnaire measured on a four-point scale cognitive restraint (6 items), uncontrolled eating (9 items) and emotional eating (3 items). Responses are measured on a four-point scale and the raw scores for each subscale are transformed to correspond to a 0-100 point scale. Higher scores in the respective scales are indicative of greater cognitive restraint, emotional eating, and uncontrolled eating. |
| Intra-subject change in food neophobia at months 0, 9, and 15. | 15 months | Food Neophobia Scale, which was adapted for a PKU population, includes nine questions measured on a seven-point scale with a higher total score indicative of greater food neophobia (score range 9-63). |
| Intra-subject change in Epicurean eating tendencies at months 0, 9, and 15. | 15 months | Epicurean eating tendencies questionnaire includes seven items measured with a seven-point scale (range 7-49). Higher scores indicative of greater Epicurean eating tendencies. |
Countries
United States
Outcome results
None listed