Study of Phenoptin to Increase Phenylalanine Tolerance in Phenylketonuric Children on a Phenylalanine-restricted Diet

BioMarin Pharmaceutical

Status and phase: Completed; Phase 3

Conditions: Phenylketonurias

Treatments: Drug: Placebo; Drug: Sapropterin Dihydrochloride

Study type: Interventional

Funder types: Industry

Identifiers

NCT00272792

PKU-006

Details and patient eligibility

About

The primary objective of this trial is to evaluate the ability of Phenoptin to increase phenylalanine (phe) tolerance in children with phenylketonuria who are following a phe-restricted diet.

Enrollment: 45 patients

Sex: All

Ages: 4 to 12 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Clinical diagnosis of PKU with hyperphenylalaninemia (HPA) documented by at least one blood Phe measurement >/=360 umol/L (6 mg/dL)
• Under dietary control with a Phe-restricted diet as evidenced by:· Estimated daily Phe tolerance </=1000 mg/day
• At least 6 months of blood Phe control (mean level of </=480 μmol/L) prior to enrolling in the study
• Aged 4 to 12 years inclusive at screening
• A blood Phe level </=480 μmol/L at screening
• Female subjects of childbearing potential (as determined by the principal investigator) must have a negative blood or urine pregnancy test at entry (prior to the first dose). Note: All female subjects of childbearing potential and sexually mature male subjects must be advised to use a medically accepted method of contraception throughout the study. Female subjects of childbearing potential must be willing to undergo periodic pregnancy tests during the course of the study
• Willing and able to comply with all study procedures
• Willing to provide written assent (if applicable) and written informed consent by a parent or legal guardian after the nature of the study has been explained and prior to any research-related procedures

Exclusion criteria

• Any condition that, in the view of the PI, renders the subject at high risk from treatment compliance and/or completing the study
• Prior history of organ transplantation
• Perceived to be unreliable or unavailable for study participation or have parents or legal guardians who are perceived to be unreliable or unavailable
• Use of any investigational agent within 30 days prior to screening, or requirement for any investigational agent or vaccine prior to completion of all scheduled study assessments
• ALT > 2 times the upper limit of normal (i.e., Grade 1 or higher based on World Health Organization Toxicity Criteria) at screening
• Concurrent disease or condition that would interfere with study participation or safety (e.g., seizure disorder, oral steroid-dependent asthma or other condition requiring oral or parenteral corticosteroid administration, or insulin-dependent diabetes)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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45 participants in 2 patient groups, including a placebo group

Sapropterin Dihydrochloride

Experimental group

Description:

Phenoptin, provided in tablets containing 100 mg of sapropterin dihydrochloride each, was administered orally once daily in the morning as the number of tablets equivalent to a 20mg/kg/day dose dissolved in 4-8 oz (120-240 mL) of water or apple juice for 6 weeks. A follow-up call or visit was made 4 weeks later during this double-blind, placebo-controlled study.

Treatment:

Drug: Sapropterin Dihydrochloride

Placebo

Placebo Comparator group

Description:

Placebo, provided as tablets similar to Phenoptin tablets, was administered orally once daily in the morning as the number of tablets equivalent to a 20mg/kg/day dose dissolved in 4 8 oz (120-240 mL) of water or apple juice. for 6 weeks. A follow-up call or visit was made 4 weeks later during this double-blind, placebo-controlled study.

Treatment:

Drug: Placebo