ABSTRACT
BACKGROUND: Enzyme replacement therapy is currently the only approved therapy for Fabry disease. From June 2009 on, viral contamination of Genzyme's production facility resulted in a worldwide shortage of agalsidase beta leading to involuntary dose reductions (approved dose 1 mg/kg/eow, reduced dose 0.5 mg/kg/m), or switch to agalsidase alpha (administered dose 0.2 mg/kg/eow). An assessment report from the European Medicines Agency (EMA) raised serious concerns about an increase in adverse events at lower dosages of agalsidase beta. We determined the influence of the shortage on clinical event incidence and the most sensitive biochemical marker (lysoGb3) in Dutch Fabry patients. METHODS: The incidence of clinical events per person per year was calculated from start of agalsidase beta treatment until the shortage, and was compared to the incidence of clinical events during the shortage period. In addition, plasma lysoGb3, eGFR, quality of life (SF-36) and brief pain inventory (BPI) questionnaires were analysed. RESULTS: All thirty-five Dutch Fabry patients using agalsidase beta (17 males) were included. Mean clinical event incidence was unchanged: 0.15 events per person per year before versus 0.15 during the shortage (p = 0.68). In total 28 clinical events occurred in 14 patients during 4.6 treatment years, compared to 7 events in 6 patients during the 1.3 year shortage period. eGFR and BPI scores were not significantly altered. Two SF-36 subscales were significantly but minimally reduced in females. In males, lysoGb3 increased with a median of 8.1 nM (range 2.5-29.2) after 1 year of shortage (p = 0.001). Increases in lysoGb3 were found in both patients switching to agalsidase alpha and on a reduced agalsidase beta dose. Antibody status, treatment duration or clinical event incidence showed no clear correlation to lysoGb3 increases. CONCLUSIONS: No increase in clinical event incidence was found in the adult Dutch Fabry cohort during the agalsidase beta shortage. Increases in lysoGb3, however, suggest recurrence of disease activity.
Subject(s)
Disease Progression , Fabry Disease/drug therapy , Fabry Disease/physiopathology , Glycolipids/blood , Isoenzymes/administration & dosage , Isoenzymes/supply & distribution , Sphingolipids/blood , alpha-Galactosidase/administration & dosage , alpha-Galactosidase/supply & distribution , alpha-Galactosidase/therapeutic use , Adolescent , Adult , Aged , Drug Administration Schedule , Enzyme Replacement Therapy/methods , Fabry Disease/epidemiology , Female , Humans , Incidence , Isoenzymes/adverse effects , Isoenzymes/therapeutic use , Male , Middle Aged , Netherlands/epidemiology , Treatment Outcome , Young Adult , alpha-Galactosidase/adverse effectsSubject(s)
Isoenzymes/supply & distribution , Orphan Drug Production , alpha-Galactosidase/supply & distribution , Drug Industry/economics , Drug Industry/legislation & jurisprudence , Drug Industry/standards , Fabry Disease/drug therapy , Humans , Isoenzymes/economics , Isoenzymes/standards , National Institutes of Health (U.S.) , Orphan Drug Production/economics , Orphan Drug Production/legislation & jurisprudence , Orphan Drug Production/standards , Patents as Topic , United States , alpha-Galactosidase/economics , alpha-Galactosidase/standardsSubject(s)
Biopharmaceutics/methods , Biotechnology/methods , Cooperative Behavior , Drug Contamination/prevention & control , Drug Contamination/statistics & numerical data , Drug Industry/methods , Biological Products/supply & distribution , Biological Products/therapeutic use , Biopharmaceutics/standards , Bioreactors/microbiology , Biotechnology/standards , Drug Industry/standards , Fabry Disease/enzymology , Fabry Disease/therapy , Humans , Isoenzymes/supply & distribution , Isoenzymes/therapeutic use , Pilot Projects , alpha-Galactosidase/supply & distribution , alpha-Galactosidase/therapeutic useABSTRACT
The shortage of enzyme for treatment of Fabry disease has caused anxiety among patients, physicians and governments. Following a request from the European Medicines Agency, consensus was reached on the temporary prioritization of patients for treatment based on disease severity and potential reversibility. Advice on follow-up of patients was agreed upon. This consensus is proposed to support the temporary guidelines issued throughout the period of ERT shortage, which will most likely last until April 2011.
Subject(s)
Isoenzymes/supply & distribution , alpha-Galactosidase/supply & distribution , Enzyme Replacement Therapy , Humans , Isoenzymes/administration & dosage , alpha-Galactosidase/administration & dosageABSTRACT
The recent shortages of enzyme replacement therapy for Fabry disease have highlighted areas of vulnerability for patients who require this treatment. Guidelines on allocation of limited stock of enzyme replacement therapy are of use for clinicians dealing with the current shortages. However, the community of metabolic physicians must advocate for changes that will minimize the impact of future drug shortages for their patients with lysosomal storage diseases.