Please assess the completion status of the following clinical trial:

Trial Title: Short-term Effects of Good Metabolic Control on Cognitive Function, Wellbeing, and Metabolic Parameters in Adult Patients With Phenylketonuria

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: None
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Men and women with classical PKU~* Age ≥ 18 years~* Good metabolic control during childhood (at least until 12 years of age)~* Plasma Phe levels ≥ 15 mg/dl for ≥ 1 year~* Written informed consent prior to study participation~Exclusion Criteria:~* Reduced cognitive function (unability to perform test battery)~* Drug and or alcohol abuse~* Treatment with BH4~* Treatment with drugs known to affect cognitive function

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: 59 Years
- Healthy Volunteers: f

Study Arms:
- Diet (Type: EXPERIMENTAL): None
- Control (Type: NO_INTERVENTION): None

Based on this trial design, predict the completion outcome and termination type (if applicable).