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The recommended dose is 20 mg TID for subjects with body weight > 20 kg and 10 mg TID for subjects with body weight ≤ 20 kg. If subject is 18 years of age or older, the recommended dose is 20 mg TID, regardless of body weight. If a subject was receiving a higher dose in study A1481156 and the investigator believes that the subject requires continued treatment on that dose, or if dose reduction is judged to be associated with pulmonary arterial hypertension (PAH) deterioration in a particular subject, the higher dose may be made available, as judged on an individual basis on discussion with the sponsor.
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