Author ORCID Identifier


Date of Graduation


Document Type

Thesis (MS)

Program Affiliation

Genetic Counseling

Degree Name

Masters of Science (MS)

Advisor/Committee Chair

Kate Richardson, M.S., CGC

Committee Member

Syed Hashmi, M.D., M.P.H., Ph.D.

Committee Member

Hope Northrup, M.D., FACMG

Committee Member

Paige Roberts, M.S., LD, RD

Committee Member

Megan Morand, M.S., CGC

Committee Member

Christina Falugi, M.S., CGC


Management for phenylketonuria (PKU) has traditionally involved adhering to a strict low-protein diet to maintain phenylalanine (Phe) levels within the recommended range (μmol/L). The time commitment and financial, emotional, and social burdens of adhering to a restrictive diet, as well as the neurocognitive symptoms associated with elevated Phe levels, make it challenging to manage PKU and lead to reductions in quality of life. Palynziq® is an enzyme substitution therapy used to lower blood Phe levels and liberate individuals with PKU from their restrictive diets. Previous studies have demonstrated the safety and efficacy of Palynziq®, but our study is the first to our knowledge to investigate the subjective impact of Palynziq® on quality of life. We surveyed 34 individuals currently treated with Palynziq® about its impact on four domains of quality of life: neurocognitive, emotional/psychiatric, social, and practical. There was a statistically significant improvement in every symptom and impact on quality of life addressed by this study after responding to Palynziq® (p < 0.05). The greatest improvements were in guilt and stress about diet and Phe levels; difficulty with planning/organization and concentration/attention; difficulty and inconvenience of diet adherence; and diet satisfaction. The majority of participants agreed or strongly agreed that Palynziq® made daily life easier and that it improved their cognitive functioning, emotional wellbeing, physical health, and social interactions. For nearly every impact on quality of life, there were no significant differences in improvement based on average Phe levels pre-Palynziq®, indicating that Palynziq® may be beneficial regardless of initial Phe levels. Quality of life aspects that remained significant challenges post-Palynziq® included the financial burden and difficulty with insurance, feeling different or isolated from others, difficulty traveling, and strain in relationships with friends and family. The results of this study indicate that Palynziq® has an overwhelmingly positive impact on quality of life overall. However, there remain social and financial challenges which should be targets for support of this patient population and may be addressed by interventions such as the involvement of social workers, counselors, and psychologists in their care, as well as increased awareness of and access to financial assistance programs.


phenylketonuria, PKU, Palynziq, pegvaliase, enzyme substitution therapy, quality of life, QoL

Available for download on Friday, April 25, 2025