Evaluation of the сlinical efficacy of PRAL-optimized specialized dietary therapeutic nutrition products for children and adults with phenylketonuria: the Antifen® line

Background: phenylketonuria (PKU) is an inherited autosomal recessive metabolic disorder characterized by a phenylalanine (Phe) metabolism defect. Effective management of PKU requires strict dietary control to prevent hyperphenylalaninemia and its neurotoxic effects, as well as other somatic complications. Achieving and maintaining metabolic homeostasis, including acid-base balance, represents a critical component of PKU therapy, particularly in patients with additional comorbidities such as renal dysfunction. Metabolic imbalances and dietary restrictions in PKU contribute to renal manifestations, which remain a common complication among patients. To mitigate renal burden, the use of specialized amino acid-based dietary formulations has garnered significant clinical interest. In particular, products incorporating glycomacropeptide or amino acid formulations with a negative potential renal acid load ( PRAL) present a promising approach to optimize both dietary therapy and renal health The novel AntiFen® product line, formulated with a negative PRAL and a balanced nutrient composition tailored to the specific age-related needs of patients with PKU, aims to reduce the risk of metabolic complications such as osteoporosis and nephropathy Aim: to assess the efficacy, safety, and tolerability of AntiFen®, a specialized pediatric medical product (SPMP), in children and adults with PKU Materials and Methods: an open-label, single-center, prospective, non-randomized, uncontrolled outpatient study was conducted. The study enrolled 29 patients (male and female), ranging from 3 months to 31 years old. Participants were stratified into five groups according to age and were treated with corresponding AntiFen® formulations: AntiFen® START (Study product (SP) 1): 5 participants under 1 year of age; AntiFen® 20 (SP-2): 5 participants aged 1–3 years; AntiFen® 40 (SP-3): 4 participants aged 3–7 years; AntiFen® 70 (SP-4): 6 participants aged 7–16 years; AntiFen® 75 (SP-5): 9 participants aged 15–31 years. The duration of product intake was 30±2 days. Parameters assessed included phenylalanine and tyrosine levels, along with therapy satisfaction as rated on the Likert scale. Results: following the use of AntiFen®, a reduction in phenylalanine levels was observed in patients, accompanied by a tendency toward increased tyrosine levels within reference ranges. Both patients' families and treating physicians reported satisfaction with the products, with families highlighting ease of adaptation to the new dietary formulations. Importantly, no stool irregularities, allergic reactions, or severe adverse events leading to therapy discontinuation were reported during the study Conclusion: the introduction of the AntiFen® product line represents a promising advancement in PKU dietary therapy These products not only help maintain metabolic control but also offer the potential to improve the quality of life in patients with PKU by minimizing associated complications such as metabolic nephropathy and bone health issues Incorporating AntiFen® into clinical practice could serve as an effective strategy in comprehensive PKU management KEYWORDS: phenylketonuria, specialized products of dietary therapeutic nutrition, phenylalanine, tyrosine, PRAL, diet therapy. FOR CITATION: Shestopalova E.A., Baydakova G.V., Kutsev S.I. Evaluation of the сlinical efficacy of PRAL-optimized specialized dietary therapeutic nutrition products for children and adults with phenylketonuria: the Antifen® line. Russian Journal of Woman and Child Health. 2025;8(1):79–85 (in Russ.). DOI: 10.32364/2618-8430-2025-8-1-12