See the DrugPatentWatch profile for sapropterin

The clinical trials for sapropterin, a drug used to reduce blood levels of phenylalanine in certain patients, have primarily focused on two patient groups: phenylketonuria (PKU) patients and hyperphenylalaninemia (HPA) patients.

PKU is a genetic disorder caused by a deficiency of the enzyme phenylalanine hydroxylase, which results in an accumulation of phenylalanine in the blood. If left untreated, PKU can lead to intellectual disability, seizures, and other serious health problems [1]. Sapropterin has been studied as a potential treatment for PKU patients to help manage their phenylalanine levels [2].

HPA is a group of disorders characterized by elevated levels of phenylalanine in the blood due to various genetic defects in the phenylalanine metabolic pathway. While HPA is not as severe as PKU, it can still cause neurological problems if left untreated [3]. Sapropterin has also been investigated as a treatment option for HPA patients [4].

In summary, sapropterin trials have mainly centered on PKU and HPA patients, with the goal of reducing phenylalanine levels in these populations.

Sources:
[1] National Institutes of Health. Phenylketonuria. Genetics Home Reference. <https://medlineplus.gov/genetics/condition/phenylketonuria/>
[2] ClinicalTrials.gov. Sapropterin Dihydrochloride in Treating Patients With Phenylketonuria. <https://clinicaltrials.gov/ct2/show/NCT00291227>
[3] National Institutes of Health. Hyperphenylalaninemia. Genetics Home Reference. <https://medlineplus.gov/genetics/condition/hyperphenylalaninemia/>
[4] ClinicalTrials.gov. Sapropterin Dihydrochloride in Treating Patients With Hyperphenylalaninemia. <https://clinicaltrials.gov/ct2/show/NCT00291240>