[Results of a prospective observational study of imiglucerase biosimilar in adults with type I Gaucher disease].

Aim: To collect and analyze real-world data on long-term enzyme replacement therapy with Glurazyme® in patients with type I Gaucher disease (GD).

Materials and methods: The study included 31 patients with type I GD (21 patients with intact spleen and 10 patients with a history of splenectomy) over 18 years. Efficacy was assessed by the change in hemoglobin level (primary endpoint), platelet count, spleen and liver volumes, prevalence of bone marrow infiltration, and the number of patients with quiet hip disease according to magnetic resonance imaging (secondary endpoints). Safety was assessed by the incidence of treatment-related adverse events and serious adverse events, as well as by the incidence of production of imiglucerase binding and neutralizing antibodies (IgG, IgE). The mean follow-up duration was 54 weeks.

Results: The study did not show a statistically significant change in hemoglobin levels, platelet count, or spleen and liver volumes. There was an upward tendency in platelet count in the overall group (p=0.1) and patients after splenectomy (p=0.08). The prevalence of specific bone marrow infiltration and the number of patients with quiet hip disease remained unchanged. During the safety analysis, one adverse reaction, a mild increase in alanine aminotransferase, was reported, which resolved spontaneously by the end of the study. The immunogenicity analysis showed the initial presence of anti-drug antibodies (ADAs) in 5 (16.7%) of the 30 examined patients. At the end of the study, ADAs were detected in only 3 (10%) patients. The detected ADAs had a low titer and no neutralizing activity, and they did not affect the treatment effectiveness.

Conclusion: Long-term therapy with the imiglucerase biosimilar was associated with a stable course of GD without progression. It was characterized by a good safety profile and low immunogenicity.