Real life data: follow-up assessment on Spanish Gaucher disease patients treated with eliglustat. TRAZELGA project

BACKGROUND

The availability of multiple treatments for type 1 Gaucher disease increases the need for real-life studies to evaluate treatment efficacy and safety and provide clinicians with more information to choose the best personalized therapy for their patients.

AIMS

To determine whether treatment with eliglustat produces, in adult GD1 patients, ans optimal response in daily clinical practice.

METHODS

We designed a real-life study with 2 years of follow-up (TRAZELGA [GEE-ELI-2017-01]) to uniformly evaluate the response and adverse events to eliglustat treatment. This study, conducted in 30 patients across Spain and previously treated with other therapies, included the evaluation of safety and efficacy by assessing visceral enlargement, bone disease (DEXA and T and Z scores), concomitant treatments and adverse events, as well as a quality of life evaluation (SF-36). In addition, the quantification of classical biomarkers (chitotriosidase activity, CCL18/PARC and glucosylsphingosine (GluSph)) and new candidates for GD biomarkers (YKL-40, cathepsin S, hepcidin and lipocalin-2 determined by immunoassay) were also assessed. Non-parametric statistical analysis was performed and p < 0.05 was considered statistically significant.

MAIN RESULTS

Thirty patients were enrolled in the study. The median age was 41.5 years and the male-female ratio was 1.1:1. 84% of the patients had received ERT and 16% SRT as previous treatment. The most common symptoms at baseline were fatigue (42%) and bone pain (38%), no patient had a bone crisis during the study, and two years after switching, 37% had reduced their use of analgesics. Patient-reported outcomes showed a significant increase in physical function scores (p = 0.027) and physical pain scores (p = 0.010). None of the enrolled patients discontinued treatment due to adverse events, which were mild and transient in nature, mainly gastrointestinal and skin dryness. None of the biomarkers show a significant increase or decompensation after switching. CCL18/PARC (p = 0.0012), YKL-40 (p = 0.00004) and lipocalin-2 (p = 0.0155) improved after two years and GluSph after one year (p = 0.0008) and two years (p = 0.0245) of oral therapy.

CONCLUSION

In summary, this real-life study, showed that eliglustat maintains stability and can improve quality of life with few side effects. Significant reductions in classic and other novel biomarkers were observed after two years of therapy.

Recommendations for oral treatment for adult patients with type 1 Gaucher disease

This work is a review of the scientific evidence on the oral treatment of adult patients with Gaucher disease type 1 (GD1) with a clinical guideline format according to the Agree II regulations. It describes the main differences between the two oral treatments currently available for treating this disease (miglustat and eliglustat). This review reminds us that the criteria for starting oral treatment in patients with GD1 must be assessed individually. Although miglustat and eliglustat are both glucosylceramide synthase (GCS) enzyme inhibitors, they have different mechanisms of action and pharmacological properties and should never be considered equivalent. Miglustat is indicated in patients with non-severe GD1 who cannot receive other first-line treatments, while eliglustat is indicated as first-line treatment for patients with GD1 of any severity without the need for prior stabilization with enzyme replacement therapy (ERT). It is important to emphasize that in order to start treatment with eliglustat, we must know the CYP2D6 metabolic phenotype and its association with drugs metabolized through the CYP2D6 and CYP3A4 cytochromes-or alternatively those that use P-Glycoprotein must be evaluated on an individual basis. During pregnancy, the use of eliglustat should be avoided; only ERT can be used. Unlike miglustat, whose adverse effects have limited its use, eliglustat has not only demonstrated similar efficacy to ERT but has also been shown to improve the quality of life of patients with GD1.

The role of glucosylsphingosine as an early indicator of disease progression in early symptomatic type 1 Gaucher disease

Gaucher disease (GD), a lysosomal storage disorder caused by β-glucocerebrosidase deficiency, results in the accumulation of glucosylceramide and glucosylsphingosine. Glucosylsphingosine has emerged as a sensitive and specific biomarker for GD and treatment response. However, limited information exists on its role in guiding treatment decisions in pre-symptomatic patients identified at birth or due to a positive family history. We present two pediatric patients with GD1 and highlight the utility of glucosylsphingosine monitoring in guiding treatment initiation.

Metabolizing profile of the cytochrome pathway CYP2D6, CYP3A4 and the ABCB 1 transporter in Spanish patients affected by Gaucher disease

Several therapeutic options are available for type 1 Gaucher disease (GD1), including enzymatic replacement therapy (ERT) and substrate reduction therapy (SRT). Eliglustat is a selective inhibitor of glucosylceramide synthase that is extensively metabolized by CYP2D6 and, to a lesser extent by CYP3A4; it is also an inhibitor of the P-gp transporter. The aim of this study is to evaluate the metabolizer profile of these cytochrome isoforms in 61 GD1 patients, and to analyze interferences with concomitant therapies. Patients were selected from the Spanish Gaucher Disease Registry considering clinical data, GBA genotype, severity score index, comorbidities, concomitant drugs, type and response to therapy and adverse effects. The polymorphisms of CYP2D6, CYP3A4 and three ABCB1 transporter variants were analyzed by Polymerase Chain Reaction (PCR). The most frequent metabolizer profile was extensive or intermediate for CYP2D6, extensive for CYP3A4*1B and CYP3A4*22 and normal activity for ABCB1. Correlations between metabolizer profile and other variables were analyzed by multiple regression study. Twenty-eight patients received ERT, 17 eliglustat and seven miglustat. Forty-two patients (68.8%) had associated diseases and 54.5% were taking daily concomitant medication. Nine patients under eliglustat therapy received concomitant drugs that interact with the CYPs and/or ABCB1, five of these did not reach therapeutic goals and three presented mild or moderate adverse effects (headache and gastrointestinal disorders). Detailed analysis in four patients with TTT haplotype, corresponding to lack of activity of the transporter, was performed. In order to apply personalized medicine and avoid interferences and adverse effects, the individual CYP metabolizer profile and transporter must be considered when choosing the concomitant medication and/or making dose adjustments.

Consequences of treatment for hemophagocytic lymphohistiocytosis in a patient with undiagnosed Gaucher disease Type 1

Gaucher disease, a lysosomal storage disorder and hemophagocytic lymphohistiocytosis (HLH), a disorder of the immune system, have several overlapping clinical features including cytopenias, elevated serum ferritin, and splenomegaly. Prior reports of acute infantile neuronopathic, Type 2 Gaucher disease manifesting with signs of HLH have been published. Here we describe an adult patient who was initially suspected of having HLH, and was treated with a 10-day course of etoposide and a 5-day course alemtuzumab for presumptive HLH, only to later to have his presentation be determined to be due to Type 1 Gaucher disease. HLH chemotherapy treatment appeared to trigger a severe Gaucher acute pain crisis and extensive bony disease including avascular necrosis. Prolonged immunosuppression, and recurrent infections further complicated a lengthy hospitalization. We discuss the clinical overlap between Gaucher and HLH and the iatrogenic consequences of HLH-directed therapy on underlying Type 1 Gaucher disease.

Peripheral neural response and sex hormones in type 1 Gaucher disease

Background

In a rare Gaucher disease, reduced activity of lysosomal b-glucocerebrosidase incompletely blocks glucosphingolipid catabolism. Accumulation of the unhydrolyzed substrate glucosylceramide within lysosomes results in progressive, multisystem Gaucher disease, classified into three types. Both parkinsonism and peripheral neuropathy are observed in cases of putative non-neuronopathic type 1 disease. In the current study we investigated whether the peripheral neural response in type 1 Gaucher disease patients, with no neural manifestations is conditioned by the influence of sex hormones.

Methods

The catalytic activity of b-glucocerebrosidase in peripheral blood leukocytes was determined spectrofluorometrically. Direct sequencing of the GBA1 gene was performed. Somatosensory evoked potentials were recorded after electrical stimulation of the median nerve of both arms. Stimuli of 0.2 ms duration at a frequency of 5 Hz were used. Sex hormones were determined by radioimmunoassay using a gamma scintillation counter.

Results

Analysis of the somatosensory evoked potentials revealed significant differences in peak latencies on periphery between men and women in both control and type 1 Gaucher disease groups. Analysis by gender showed significant associations between latencies and sex hormones only in female patients: negative correlation between oestradiol concentration and N9 peak latency, and a strong negative correlation of testosterone levels with all peak latencies on the periphery (N9-N13).

Conclusions

A relationship between testosterone concentrations and the latencies of potentials evoked on peripheral nerves exists only in females with type 1 Gaucher disease. We point out sexual dimorphism in the development of this entity.

Attitudes of Individuals with Gaucher Disease toward Substrate Reduction Therapies

Type 1 Gaucher disease (GD) is the most common lysosomal storage disorder. Previously, treatment for GD was limited to intravenous enzyme replacement therapies (ERTs). More recently, oral substrate reduction therapies (SRTs) were approved for treatment of GD. Although both therapies alleviate disease symptoms, attitudes toward SRTs and patient perceptions of health while using SRT have not been well established. Electronic surveys were administered to adults with GD and asked about treatment history, attitudes toward SRTs, and perception of health while using SRTs as compared to ERTs, if applicable to the participant. ERT users that were offered treatment with SRTs cited potential side effects, wanting more research on SRTs, and satisfaction with their current treatment regimen as reasons for declining SRTs. SRT users expressed convenience and less invasiveness as reasons for choosing SRTs. Additionally, those using SRTs most often perceived their health to be similar to when they previously used ERT. Participant responses illustrate that attitudes toward SRTs can be variable and that one particular treatment may not be ideal for all patients with GD depending on individual perceptions of factors such as convenience, invasiveness, or side effects. Thus, individuals with GD should be counseled adequately by healthcare providers about both ERTs and SRTs for treatment of GD now that SRTs are clinically available.

Management and monitoring recommendations for the use of eliglustat in adults with type 1 Gaucher disease in Europe

PURPOSE

In Gaucher disease, diminished activity of the lysosomal enzyme, acid β-glucosidase, leads to accumulation of glucosylceramides and related substrates, primarily in the spleen, liver, and bone marrow. Eliglustat is an oral substrate reduction therapy approved in the European Union and the United States as a first-line treatment for adults with type 1 Gaucher disease who have compatible CYP2D6 metabolism phenotypes. A European Advisory Council of experts in Gaucher disease describes the characteristics of eliglustat that are distinct from enzyme augmentation therapy (the standard of care) and miglustat (the other approved substrate reduction therapy) and recommends investigations and monitoring for patients on eliglustat therapy within the context of current recommendations for Gaucher disease management.

RESULTS

Eliglustat is a selective, potent inhibitor of glucosylceramide synthase, the enzyme responsible for biosynthesis of glucosylceramides which accumulate in Gaucher disease. Extensive metabolism of eliglustat by CYP2D6, and, to a lesser extent, CYP3A of the cytochrome P450 pathway, necessitates careful consideration of the patient's CYP2D6 metaboliser status and use of concomitant medications which share metabolism by these pathways. Guidance on specific assessments and monitoring required for eliglustat therapy, including an algorithm to determine eligibility for eliglustat, are provided.

CONCLUSIONS

As a first-line therapy for type 1 Gaucher disease, eliglustat offers eligible patients a daily oral therapy alternative to biweekly infusions of enzyme therapy. Physicians will need to carefully assess individual Gaucher patients to determine their appropriateness for eliglustat therapy. The therapeutic response to eliglustat and use of concomitant medications will require long-term monitoring.

Case report of cholelithiasis in a patient with type 1 Gaucher disease

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Case report of cholelithiasis in a patient with type 1 Gaucher disease; which is very intriguing to show this comorbidity.

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The case was the only known case with this pathology in time of diagnosis in our country (Kosovo).

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Thus, gallstones and cholecystitis should be considered when abdominal symptoms and liver dysfunctions are seen in these patients.

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More studies are needed to determine the incidence and prevalence of gallstones in Gaucher disease patients in especially Kosovo.

Introduction

Patients with type 1 Gaucher disease have been reported to be more likely to have cholelithiasis.

Presentation of case

A case of cholelithiasis in a patient with type 1 Gaucher disease; which is very intriguing to show this comorbidity. The case was the only known case with this pathology in time of diagnosis in our country (Kosovo). The patient is a 21-year old girl a known case of type 1 Gaucher disease, at the age of 8 years. The patient underwent elective laparoscopic cholecystectomy. Chronic inflammatory changes and adhesions were obvious during surgery.

Discussion

Type 1 Gaucher disease patients have several risk factors for gallstone formation: increased biliary excretion of glucosylceramide, advanced liver disease and cirrhosis, splenomegaly, inborn error of metabolism, chronic systemic inflammation, T cell dysfunction, and insulin resistance” to risk factors.

Conclusion

Gallstones and cholecystitis should be considered when abdominal symptoms and liver dysfunctions are seen in these patients. More studies are needed in especially Kosovo.

Patients with type 1 Gaucher disease in Spain: A cross-sectional evaluation of health status

A multicentre, cross-sectional epidemiological survey was conducted to describe the health status of patients with type 1 Gaucher disease (GD1) in Spain. Patient data were collected retrospectively from clinical records. Therapeutic goals for seven clinical parameters were chosen as primary outcome measures. 108 GD1 patients (mean age 44.8 years; 53% male) were recruited from 28 hospitals. Ninety-five patients (88%) were receiving treatment for GD1. Hemoglobin concentration was the therapeutic goal with the highest level of achievement, being met by 105 of 108 patients (97%), followed by the goals for liver volume (86/98 patients; 88%), spleen volume (67/77 patients; 87%) and platelet count (81/108 patients; 75%). The goal for bone mineral density (BMD) was met by 48 of 75 patients (64%), and the goal for quality of life was met by 65 of 103 patients (63%). Bone pain was the parameter with the lowest level of achievement (goal met by 50/94 patients; 53%). The clinical information most often missing from patient records was the BMD Z-score (missing for 31% of patients). These data suggest that most Spanish GD1 patients have good control over hematological and visceral parameters, but there is a need to improve monitoring and treatment of GD-related bone disease.