Best practice recommendations for the management of anxiety during the pegvaliase journey.

BACKGROUND: Pegvaliase, an enzyme substitution therapy, is a treatment option for phenylketonuria (PKU). Due to the neuropathophysiology and disease burden of PKU, individuals can experience baseline anxiety unrelated to pegvaliase therapy. In addition, there are aspects of pegvaliase therapy that may be anxiety-inducing for those considering or receiving treatment. The aim of this manuscript is to present best practice recommendations for the identification and management of anxiety symptoms that can occur along the pegvaliase journey. METHODS: A modified Delphi approach was used to seek consensus among a multidisciplinary panel of experts. To this end, an in-person meeting was held that was preceded by a medical specialist- and patient-specific survey to develop preliminary recommendations on ways to address anxiety along the pegvaliase journey. After the meeting, an additional survey was conducted to rank the proposed solutions and mitigation strategies from which a set of recommendations was developed. All recommendations were voted on with the aim of consensus generation, defined as achieving ≥75% agreement among experts. RESULTS: The panel reached consensus on a total of 28 best practice recommendations for the management of anxiety during the pre-treatment, induction and titration, early maintenance (pre-efficacy), and late maintenance (post-efficacy) stages. The recommendations offer strategies to identify and address the most common causes of pegvaliase-related anxiety, including self-injection, side effects, the titration schedule, prescribed dietary changes, and variable time to efficacy. Overall, managing anxiety in those considering or receiving pegvaliase involves patient-centered communication, shared decision-making, and personalized treatment plans. CONCLUSIONS: The best practice recommendations described herein can guide healthcare providers in proactively addressing anxiety during the different stages of pegvaliase treatment, and support providers with initiating and managing pegvaliase in individuals who may experience baseline and treatment-related anxiety.

Use of pegvaliase in the management of phenylketonuria: Case series of early experience in US clinics.

OBJECTIVE: To present a case series that illustrates real-world use of pegvaliase based on the initial experiences of US healthcare providers. METHODS: Sixteen healthcare providers from 14 centers across the US with substantial clinical experience in treating patients with phenylketonuria (PKU) with pegvaliase in the two-plus years since FDA approval (May 2018) provided cases that exemplified important lessons from their initial experiences treating patients with pegvaliase. Key lessons from each case and takeaway points were discussed in both live and virtual meetings. RESULTS: Fifteen cases of adults with PKU (eight males, seven females), representing a spectrum of age (18 to 53 years), previous PKU care, comorbidities, and socioeconomic situations were reviewed and discussed. Full extended case reports are included in the Supplement. The cases showed that treating patients with a daily injectable can be challenging due to a patient's financial problems, treatment challenges, and neuropsychological and psychiatric comorbidities, which can be identified before starting pegvaliase, but do not prohibit successful treatment. The authors agreed that patient education on adverse events (AEs), time to efficacy, dietary changes, and food preparation is an ongoing process that should start prior to initiating pegvaliase treatment. Treatment goals and planned dietary changes once efficacy is reached should be defined prior to treatment initiation and re-evaluated throughout the course of therapy. Each patient's titration schedule and dietary adjustments are unique, depending on occurrence of AEs and individual goals of treatment. Despite the AE profile of pegvaliase, all but two patients remained motivated to continue treatment and achieved efficacy (except one patient in whom titration was still ongoing). AEs occurring early in the treatment pathway may require prolongation of the titration phase and/or concomitant medication use, but do not seem indicative of future tolerability or eventual efficacy. Close follow-up of patients during titration and maintenance to help with dietary changes is important. CONCLUSION: This case series provides real-world experience on the use of pegvaliase. Until data from registries and independent research become available, the data presented herein can support appropriate management of patients receiving pegvaliase in clinical practice.

Strategies to engage lost to follow-up patients with phenylketonuria in the United States: Best practice recommendations.

BACKGROUND: Phenylketonuria (PKU) is a rare autosomal recessive disorder caused by mutations in the gene encoding phenylalanine hydroxylase, an enzyme that converts phenylalanine to tyrosine. Untreated, PKU is characterized by a range of neuropsychological and neurocognitive impairments. Due to ubiquitous newborn genetic screening programs, treatment for PKU can be commenced shortly after birth and can prevent many of the severe manifestations of the disease. However, lifelong management is critical for patients with PKU as high levels of phenylalanine are neurotoxic. As for all chronic diseases, long-term management can be challenging and most adult patients with PKU become lost to follow-up (LTFU). A survey of PKU clinics across the United States and a multidisciplinary Expert Meeting were conducted to develop best practices to engage LTFU patients with PKU. RESULTS: We defined LTFU patients with PKU as "patients with no contact with the clinic for at least 2 consecutive years." Combining the results from our survey and our discussion at the Expert Meeting, we have prepared six best practice recommendations to engage LTFU patients with PKU: 1) Ensure patients are aware of the current treatment guidelines for PKU; 2) Communicate to patients any new treatment and diet options as they become available for PKU; 3) Consider the neuropsychological and neurocognitive aspects of PKU; 4) Prioritize motivated LTFU patients; 5) Explore new approaches of outreach to LTFU patients; and 6) Formalize approaches to track and/or identify PKU patients. CONCLUSION: We strongly advocate the importance of engaging LTFU patients with PKU and encourage implementation of our best practice recommendations. Although it takes time and effort to engage LTFU patients, we believe that clinics are capable of supporting this significant patient group.