A Case Study Analyzing PALYNZIQ (pegvvaliase) Use in Phenylketonuria Patients During Pregnancy




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The purpose of this case study is to determine the efficacy and safety of pegvaliase therapy for PKU patients during pregnancy. For my thesis, I hypothesized that PALYNZIQ® (pegvaliase) would be safe for use in maternal PKU cases and facilitate Phe level control to decrease the risk of congenital abnormalities in maternal PKU cases. This retrospective case study collected de-identified data from UT Southwestern Medical Center patient medical records who had a diagnosis of PKU and remained on pegvaliase therapy throughout their pregnancy. Fetal outcomes of the cases included in this study were compared with those of uncontrolled maternal PKU cases. Additionally, the correlation between Phe levels and pegvaliase dose changes throughout the pregnancies was assessed. Finally, the trimester Phe and Tyr level averages of this study were compared to population averages in healthy pregnancies. Results showed decreased frequencies of spontaneous abortion, microcephaly, and CHD. No statistical correlation was identified between Phe level and pegvaliase dose. Trimester averages of Phe and Tyr levels were comparable to healthy populations. In conclusion, pegvaliase proved an effective and safe treatment for managing PKU patients during pregnancy in the cases treated at UT Southwestern Medical Center.