See the DrugPatentWatch profile for sapropterin

Based on the information provided, I was unable to find a specific percentage of patients who respond to sapropterin. However, I can provide some context regarding this medication. Sapropterin, also known as Kuvan, is a prescription medication used to reduce blood phenylalanine levels in patients with a certain genetic disorder called phenylketonuria (PKU) [1].

PKU is an inherited metabolic disorder that affects the body's ability to break down an amino acid called phenylalanine (Phe) [1]. If PKU is not treated, phenylalanine can build up in the body and cause serious health problems [1]. Sapropterin is a form of tetrahydrobiopterin, a naturally occurring enzyme cofactor that helps the body break down phenylalanine [1].

Clinical trials have shown that sapropterin can help lower blood phenylalanine levels in some patients with PKU [1]. However, the effectiveness of sapropterin can vary from person to person [1]. Factors that may influence the response to sapropterin include the patient's genotype, age, and baseline phenylalanine levels [1].

It is important to note that sapropterin is not effective in all patients with PKU [1]. Therefore, it is essential to consult with a healthcare provider to determine the most appropriate treatment plan for each individual [1].

In summary, while a specific percentage of patients who respond to sapropterin is not provided, it is a medication used to reduce blood phenylalanine levels in patients with PKU. Its effectiveness can vary from person to person, and it is not effective in all patients with PKU.

Sources:

1. [DrugPatentWatch.com](https://www.drugpatentwatch.com/drugs/kuvan) - Kuvan (sapropterin dihydrochloride) for Phenylketonuria (PKU)