Patient reported quality of life and medication adherence in Fabry disease patients treated with migalastat: A prospective, multicenter study.

AIMS: Chaperone therapy with migalastat is a novel therapy option in Fabry disease (FD). In contrast to biweekly intravenous enzyme-replacement-therapy in a healthcare setting, oral delivery of migalastat every other day relies on the patient self-administration. Therapy adherence to migalastat and patient reported outcomes have not yet been studied in a real-world scenario. METHODS AND RESULTS: Prospective multicenter 'MigALastat Therapy Adherence among FABRY patients' (MALTA-FABRY) study examined therapy adherence and patient-reported outcomes including quality of life in FD-patients receiving migalastat. Outcome measurements were elicited by the 'Medication Adherence Questionnaire (MAQ)', 'SF-36' and 'Fabry Pain Questionnaire' over a follow-up period of 24 months. Therapy adherence was graded as high (MAQ score of 4), medium (score of 2-3) or low (score 0-1). Within the recruitment period between 2017 and 2021, 40 patients (19 females) from 3 German FD-centers were included in the study. Nearly all patients (n = 37, 92.5%) showed good therapy adherence (MAQ6Mmean:3.93, MAQ12Mmean:3.71 and MAQ24Mmean:3.7). Only one patient fulfilled criteria for low adherence. Patient reported outcomes with completed SF-36 questionnaires were available in 28 patients (14 females). Over 24 months, significant improvement of pain and life role limitations due to physical activity was reported (Pain: change from baseline: 8.57 points, 95%-CI: 1.32-15.82, p = 0.022; role limitations physical: change from baseline: 13.39 points, 95%-CI: 0.61-23.2, p = 0.048). CONCLUSION: Migalastat therapy adherence in FD-patients was high and remained high over a follow-up period of 2 years. Patient reported quality of life remained mostly stable, while pain and physical limitations improved over time.

Gene variants of unknown significance in Fabry disease: Clinical characteristics of c.376A>G (p.Ser126Gly).

BACKGROUND: Anderson-Fabry disease (FD) is an X-linked lysosomal storage disorder with varying organ involvement and symptoms, depending on the underlying mutation in the alpha-galactosidase A gene (HGNC: GLA). With genetic testing becoming more readily available, it is crucial to precisely evaluate pathogenicity of each genetic variant, in order to determine whether there is or might be not a need for FD-specific therapy in affected patients and relatives at the time point of presentation or in the future. METHODS: This case series investigates the clinical impact of the specific GLA gene variant c.376A>G (p.Ser126Gly) in five (one heterozygous and one homozygous female, three males) individuals from different families, who visited our center between 2009 and 2021. Comprehensive neurological, nephrological and cardiac examinations were performed in all cases. One patient received a follow-up examination after 12 years. RESULTS: Index events leading to suspicion of FD were mainly unspecific neurological symptoms. However, FD-specific biomarkers, imaging examinations (i.e., brain MRI, heart MRI), and tissue-specific diagnostics, including kidney and skin biopsies, did not reveal evidence for FD-specific symptoms or organ involvement but showed normal results in all cases. This includes findings from 12-year follow-up in one patient with renal biopsy. CONCLUSION: These findings suggest that p.Ser126Gly represents a benign GLA gene variant which per se does not cause FD. Precise clinical evaluation in individuals diagnosed with genetic variations of unknown significance should be performed to distinguish common symptoms broadly prevalent in the general population from those secondary to FD.

Will the FAbry STabilization indEX make its way to everyday clinical practice?

Despite several attempts at setting up a standardized disease severity score for Fabry disease in the past, none have been established in routine clinical practice due to the multisystem nature and complexity of this inherited enzyme deficiency disorder. In this issue, Mignani et al. report a large multicentre application of the FASTEX, an online tool to assess disease progress over time that offers simple data inputting and graphic illustration of disease progression or stabilization. Mignani et al. succeeded in validating the tool in a large cohort of Fabry patients, including females and non-classical phenotypes, building on the first FASTEX introduction in 2016. We report on our own practical experience with the tool and comment on some limiting factors in its use as well as possible future prospects.

Oral Chaperone Therapy Migalastat for Treating Fabry Disease: Enzymatic Response and Serum Biomarker Changes After 1 Year.

Long-term effects of migalastat therapy in clinical practice are currently unknown. We evaluated migalastat efficacy and biomarker changes in a prospective, single-center study on 14 patients with Fabry disease (55 ± 14 years; 11 men). After 1 year of open-label migalastat therapy, patients showed significant changes in alpha-galactosidase-A activity (0.06-0.2 nmol/minute/mg protein; P = 0.001), left ventricular myocardial mass index (137-130 g/m2 ; P = 0.037), and serum creatinine (0.94-1.0 mg/dL; P = 0.021), accounting for deterioration in estimated glomerular filtration rate (87-78 mL/minute/1.73 m2 ; P = 0.012). The enzymatic increase correlated with myocardial mass reduction (r = -0.546; P = 0.044) but not with renal function (r = -0.086; P = 0.770). Plasma globotriaosylsphingosine was reduced in therapy-naive patients (10.9-6.0 ng/mL; P = 0.021) and stable (9.6-12.1 ng/mL; P = 0.607) in patients switched from prior enzyme-replacement therapy. These first real-world data show that migalastat substantially increases alpha-galactosidase-A activity, stabilizes related serum biomarkers, and improves cardiac integrity in male and female patients with amenable Fabry disease mutations.

Hot topics in Fabry disease.

Fabry disease is a rare inborn error of the enzyme α-galactosidase (α-Gal) and results in lysosomal substrate accumulation in tissues with a wide range of clinical presentations. The disease has attracted a lot of interest over the last years, in particular since enzyme replacement therapy (ERT) has become widely available in 2001. With rising awareness and rising numbers of (diagnosed) patients, physicians encounter new challenges. Over 900 α-Gal gene mutations are currently known, some with doubtful clinical significance, posing diagnostic and prognostic difficulties for the clinician and a lot of uncertainty for patients. Another challenge are patients who develop neutralising antibodies to ERT, which possibly leads to reduced therapy effectiveness. In this article, we summarise the latest developments in the science community regarding diagnostics and management of this rare lysosomal storage disorder and offer an outlook to future treatments.