See the DrugPatentWatch profile for sapropterin

Sapropterin's effectiveness varies among patients, and this variability is attributed to several factors. According to the National Organization for Rare Disorders (NORD) [1], sapropterin's efficacy depends on the patient's phenylalanine (Phe) levels, Phe tolerance, and genotype.

Clinical trials have shown that sapropterin reduces blood Phe levels in approximately 30-50% of patients with phenylketonuria (PKU) [1]. However, the response to sapropterin can differ significantly among patients. Some patients may experience a substantial decrease in Phe levels, while others may not respond to the treatment at all [1].

Furthermore, the American College of Medical Genetics and Genomics (ACMG) states that sapropterin's efficacy is influenced by the patient's genotype [2]. Specifically, patients with certain genetic mutations, such as those in the PAH gene, are more likely to respond to sapropterin [2].

It is important to note that sapropterin's effectiveness may also be influenced by the patient's diet and adherence to treatment [1]. Therefore, regular monitoring of Phe levels and dietary compliance is crucial for optimizing sapropterin's effectiveness.

In summary, sapropterin's effectiveness varies among patients, and its efficacy depends on several factors, including Phe levels, Phe tolerance, genotype, and dietary compliance.

Sources:
[1] <https://rarediseases.org/rare-disease-information/rare-diseases/by-system/genetic-and-metabolic-disorders/phenylketonuria/>
[2] <https://www.ncbi.nlm.nih.gov/books/NBK1116/>