Patient case (clinical description): A 4-year-old boy comes to the office for the follow up of his confirmed oculocutaneous albinism.  The patient was born at 38 weeks gestation with no complications.  Vital signs are normal.  Weight and height are at the 50th percentile.  On examination, iris transillumination is present, and there are no apparent foveae on funduscopic examination.  Optic nerves are small and gray.  All the hairs including eyebrows and lashes are white.

Patient's own account: I brought my four-year-old son to his follow-up consultation for his albinism. All his hair is white, even lashes and eyebrows. My baby was born at 38 weeks pregnant with no complications whatsoever. During the consultations his vitals were normal and now his weight and height are at the 50th percentile. The doctor did an eye exam and it seems that his iris has a kind of transillumination, and there are no foveae. The doctor told me that his optic nerves are small and gray.

Clinical trial: Nitisinone for Type 1B Oculocutaneous Albinism

Eligibility criteria:
-  INCLUSION CRITERIA:

        To be eligible, the following inclusion criteria must be met, when applicable.

          1. Participant must be 18 years of age or older.

          2. Participant must understand and sign the protocol s informed consent document.

          3. Participant must have normal renal function, liver function, and platelet counts or
             have mild abnormalities no greater than grade 1 as defined by the Common Terminology
             Criteria for Adverse Events v4.0 (CTCAE).

          4. Any female participant of childbearing potential must have a negative pregnancy test
             at screening and must be willing to undergo pregnancy testing immediately prior to the
             start of the investigational product and while on the investigational product.

          5. Any female participant of childbearing potential and any male participant able to
             father children must have (or have a partner who has) had a hysterectomy or vasectomy,
             be completely abstinent from intercourse, or must agree to practice two effective
             methods of contraception while taking the investigational product and for at least two
             months following the last dose of investigational product. Acceptable methods of
             contraception include:

               -  Hormonal contraception (i.e., birth control pills, injected hormones, dermal
                  patch, or vaginal ring),

               -  Intrauterine device,

               -  Barrier methods (diaphragm, condom) with spermicide, or

               -  Surgical sterilization (tubal ligation).

          6. Participant must have OCA1B, as defined by ALL (a-d) of the following criteria:

               1. Participant has ophthalmic signs or symptoms of albinism, including:

                    -  Bilateral visual acuity E-ETDRS EVA letter score of less than or equal to 83
                       (i.e., Snellen equivalent of 20/25 or worse) that is not attributable to any
                       other pathology.

                    -  Bilateral iris transillumination that can be seen in clinical photographs.

               2. Predominant contralateral decussation of ganglion cell axons, as determined by
                  pattern visual evoked potential (VEP).

               3. Participant has at least one definitive mutation in the OCA1 gene (tyrosinase).

               4. Participant has no definitive mutations in the OCA2 gene.

        EXCLUSION CRITERIA:

          -  Participant is pregnant or breast-feeding.

          -  Participant is a male AND has a definitive mutation in the OA1 gene.

          -  Participant has any of the following abnormal laboratory test results:

               1. Serum potassium < 3.0 mEq/L,

               2. Serum CK > 500 U/L,

               3. Hemoglobin < 10.0 g/dL,

               4. White blood cell (WBC) count < 3.0 k/microL,

               5. Plasma tyrosine > 150 microM,

               6. ESR > 100 mm/h, and/or

               7. Serum T4 > 15 microg/dL OR Serum T4 < 4 microg/dL.

          -  Participant has keratopathy.

          -  Participant has a current malignancy.

          -  Participant has open skin lesions.

          -  Participant is on a diet that deliberately increases protein intake to
             disproportionate levels (e.g., Atkins diet). The diet must be reasonably balanced, as
             determined by a dietician.

          -  Participant has uncontrolled hypertension, defined as systolic blood pressure above
             180 mmHg or diastolic blood pressure above 95 mmHg.

          -  Participant has another chronic ocular disease that may confound the results of visual
             tests, such as age-related macular degeneration, cataract of possible visual
             significance, or uncontrolled glaucoma.

          -  Participant drinks more than the equivalent of two glasses of wine per day on average,
             has a history of alcohol abuse, or has a severe liver illness.

          -  Participant s liver is > 3 cm below the right costal margin.

          -  Participant has a muscle disease.

          -  Participant is currently taking a medication known to cause elevated liver function
             tests including statins/HMG-Co-A reductase inhibitors (e.g., lovastatin, simvastatin);
             anti-epileptic medications (e.g., carbamazepine, phenytoin, phenobarbital);
             tetracycline or its derivatives, if used chronically; acetaminophen, if used
             daily/chronically; amiodarone; and any other medications with known significant liver
             toxicity.
No condition on gender to be admitted to the trial.
No healthy subjects accepted to join the trial.
Subject must be at least 18 Years old.


Eligibility (NLI label): Contradiction