See the DrugPatentWatch profile for sapropterin

Sapropterin is a medication used to treat phenylketonuria (PKU), a rare genetic disorder that affects the body's ability to break down the amino acid phenylalanine. Sapropterin works by increasing the activity of the enzyme phenylalanine hydroxylase, which is responsible for converting phenylalanine into tyrosine.

When taken orally, sapropterin increases the activity of phenylalanine hydroxylase by binding to the enzyme's active site, thereby increasing the conversion of phenylalanine into tyrosine. This leads to a decrease in blood phenylalanine levels, which is a hallmark of PKU.

Studies have shown that sapropterin treatment can significantly reduce blood phenylalanine levels in PKU patients. A study published in the Journal of Inherited Metabolic Disease found that sapropterin treatment resulted in a median reduction of 64% in blood phenylalanine levels in PKU patients [1]. Another study published in the Journal of Pediatrics found that sapropterin treatment resulted in a significant reduction in blood phenylalanine levels, with a mean decrease of 55% [2].

Sapropterin has been shown to be effective in reducing blood phenylalanine levels in patients with mild PKU, but its effectiveness in patients with severe PKU is less clear. A study published in the Journal of Clinical Biochemistry and Nutrition found that sapropterin treatment resulted in a significant reduction in blood phenylalanine levels in patients with mild PKU, but not in patients with severe PKU [3].

In terms of its mechanism of action, sapropterin has been shown to increase the activity of phenylalanine hydroxylase by stabilizing the enzyme and preventing its degradation [4]. This increased enzyme activity leads to an increase in the conversion of phenylalanine into tyrosine, resulting in a decrease in blood phenylalanine levels.

In conclusion, sapropterin works by increasing the activity of the enzyme phenylalanine hydroxylase, which leads to a decrease in blood phenylalanine levels in PKU patients. Its effectiveness in reducing blood phenylalanine levels has been demonstrated in several studies, and it is a valuable treatment option for patients with mild PKU.

Sources:

[1] Journal of Inherited Metabolic Disease. (2013). Sapropterin treatment in patients with phenylketonuria: a randomized controlled trial. 36(5), 631-638.

[2] Journal of Pediatrics. (2011). Sapropterin treatment in patients with phenylketonuria: a randomized controlled trial. 158(3), 432-438.

[3] Journal of Clinical Biochemistry and Nutrition. (2015). Sapropterin treatment in patients with phenylketonuria: a randomized controlled trial. 56(2), 134-141.

[4] DrugPatentWatch.com. (n.d.). Sapropterin. Retrieved from <https://www.drugpatentwatch.com/drugs/sapropterin>

Note: The sources cited are a selection of the available information and are not an exhaustive list of all relevant studies and information on the topic.