Treatment-naïve Gaucher disease patients achieve therapeutic goals and normalization with velaglucerase alfa by 4years in phase 3 trials

Current and Emerging Therapies for Lysosomal Storage Disorders

Lysosomal storage disorders (LSDs) are rare inherited metabolic disorders characterized by defects in the function of specific enzymes responsible for breaking down substrates within cellular organelles (lysosomes) essential for the processing of macromolecules. Undigested substrate accumulates within lysosomes, leading to cellular dysfunction, tissue damage, and clinical manifestations. Clinical features vary depending on the degree and type of enzyme deficiency, the type and extent of substrate accumulated, and the tissues affected. The heterogeneous nature of LSDs results in a variety of treatment approaches, which must be tailored to patient presentation and characteristics. The treatment landscape for LSDs is rapidly evolving. An up-to-date discussion of current evidence is required to provide clinicians with an appropriate overview of treatment options. Therefore, we aimed to review current and ongoing trials pertaining to the treatment of common LSDs.

Systematic Review of Genetic Substrate Reduction Therapy in Lysosomal Storage Diseases: Opportunities, Challenges and Delivery Systems

BACKGROUND

Genetic substrate reduction therapy (gSRT), which involves the use of nucleic acids to downregulate the genes involved in the biosynthesis of storage substances, has been investigated in the treatment of lysosomal storage diseases (LSDs).

OBJECTIVE

To analyze the application of gSRT to the treatment of LSDs, identifying the silencing tools and delivery systems used, and the main challenges for its development and clinical translation, highlighting the contribution of nanotechnology to overcome them.

METHODS

A systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) reporting guidelines was performed. PubMed, Scopus, and Web of Science databases were used for searching terms related to LSDs and gene-silencing strategies and tools.

RESULTS

Fabry, Gaucher, and Pompe diseases and mucopolysaccharidoses I and III are the only LSDs for which gSRT has been studied, siRNA and lipid nanoparticles being the silencing strategy and the delivery system most frequently employed, respectively. Only in one recently published study was CRISPR/Cas9 applied to treat Fabry disease. Specific tissue targeting, availability of relevant cell and animal LSD models, and the rare disease condition are the main challenges with gSRT for the treatment of these diseases. Out of the 11 studies identified, only two gSRT studies were evaluated in animal models.

CONCLUSIONS

Nucleic acid therapies are expanding the clinical tools and therapies currently available for LSDs. Recent advances in CRISPR/Cas9 technology and the growing impact of nanotechnology are expected to boost the clinical translation of gSRT in the near future, and not only for LSDs.

Twelve Years of the Gaucher Outcomes Survey (GOS): Insights, Achievements, and Lessons Learned from a Global Patient Registry

Background: Long-term patient registries are important for evaluating treatment outcomes in patients with rare diseases, and can provide insights into natural disease history and progression in real-world clinical practice. Initiated in 2010, the Gaucher Outcome Survey (GOS) is an ongoing, international, multicenter, observational registry (ClinicalTrials.gov Identifier: NCT03291223) for patients with a diagnosis of Gaucher disease (GD), irrespective of treatment type or status, with a primary objective to monitor safety and long-term effectiveness of velaglucerase alfa. Methods: Here, we evaluated the GOS population 12 years after the registry initiation. Results: As of 25 February 2023, 2084 patients enrolled in the GOS and 1643 received GD-specific treatment. Patients exhibited broad heterogeneity at baseline: age of diagnosis (0 to 85.3 years), hemoglobin concentrations (<80.0 g/L to >150 g/L), platelet counts (<50 × 109/L to >450 × 109/L), and liver and spleen volumes. Most patients treated with enzyme replacement therapy or substrate reduction therapy reported improvements in clinical parameters within 1 year of treatment initiation, maintained over the course of treatment up to 12 years, whereas untreated patients had baseline values closer to standard reference thresholds and showed stability over time. Conclusion: The 12-year data from the GOS confirm the impact of long-term treatment with GD-specific agents and offer insights into disease progression and outcomes in a real-world setting.

A Feasibility Open-Labeled Clinical Trial Using a Second-Generation Artificial-Intelligence-Based Therapeutic Regimen in Patients with Gaucher Disease Treated with Enzyme Replacement Therapy

Background/Objectives: Gaucher Disease type 1 (GD1) is a recessively inherited lysosomal storage disorder caused by a deficiency in the enzyme β-glucocerebrosidase. Enzyme replacement therapy (ERT) has become the standard of care for patients with GD. However, over 10% of patients experience an incomplete response or partial loss of response to ERT, necessitating the exploration of alternative approaches to enhance treatment outcomes. The present feasibility study aimed to determine the feasibility of using a second-generation artificial intelligence (AI) system that introduces variability into dosing regimens for ERT to improve the response to treatment and potentially overcome the partial loss of response to the enzyme. Methods: This was an open-label, prospective, single-center proof-of-concept study. Five patients with GD1 who received ERT were enrolled. The study used the Altus Care™ cellular-phone-based application, which incorporated an algorithm-based approach to offer random dosing regimens within a pre-defined range set by the physician. The app enabled personalized therapeutic regimens with variations in dosages and administration times. Results: The second-generation AI-based personalized regimen was associated with stable responses to ERT in patients with GD1. The SF-36 quality of life scores improved in one patient, and the sense of change in health improved in two; platelet levels increased in two patients, and hemoglobin remained stable. The system demonstrated a high engagement rate among patients and caregivers, showing compliance with the treatment regimen. Conclusions: This feasibility study highlights the potential of using variability-based regimens to enhance ERT effectiveness in GD and calls for further and longer trials to validate these findings.

A Real-World Investigation of MRI Changes in Bone in Patients with Type 1 Gaucher Disease Treated with Velaglucerase Alfa: The EIROS Study

Background/Objectives: Gaucher disease type 1 (GD1) is characterized by hepatosplenomegaly, thrombocytopenia, and disabling bone manifestations requiring regular MRI monitoring. The EIROS study assessed the real-world impact of velaglucerase alfa on GD1 bone disease, using MRI data collected in French clinical practice. Methods: MRIs collected retrospectively from treatment initiation and prospectively during follow-up (12-months) were analyzed centrally by a blinded expert radiologist to evaluate bone infiltration using the Bone Marrow Burden (BMB) score and a qualitative method (stable, improved or worsened for the spine and femur). Abdominal MRIs were also centrally analyzed to assess hepatosplenomegaly. Bone manifestations, hepatosplenomegaly, and hematologic parameters were analyzed from medical records. Results: MRI data were available for 20 patients: 6 treatment-naive patients and 14 patients who switched to velaglucerase alfa from another GD treatment. Interpretable MRIs for BMB scoring were available for seven patients for the spine and one patient for the femur. Qualitative assessments (n = 18) revealed stability in spine and femur infiltration in 100.0% and 84.6% of treatment-switched patients (n = 13), respectively, and improvements in 80.0% and 60.0% of treatment-naive patients (n = 5), respectively; no worsening of bone infiltration was observed. Liver, spleen, and hematologic parameters improved in treatment-naive patients and remained stable in treatment-switched patients. Conclusions: The qualitative real-world data support findings from clinical trials suggesting the long-term effectiveness of velaglucerase alfa on GD1 bone manifestations. When MRI assessment by radiologists with experience of GD is not possible, a simplified qualitative assessment may be sufficient in clinical practice for monitoring bone disease progression and treatment response.

Long-Term Treatment of Gaucher Disease with Velaglucerase Alfa in ERT-Naïve Patients from the Gaucher Outcome Survey (GOS) Registry

Background: Gaucher disease (GD) is a rare, autosomal, recessive condition characterized by hepatosplenomegaly, thrombocytopenia, anemia, and bone abnormalities, often requiring life-long treatment. Velaglucerase alfa has improved hematologic and visceral parameters in clinical trials; however, limited long-term efficacy and safety data are available. Methods: The Gaucher Outcome Survey (GOS), a structured and validated international registry for patients with confirmed GD, provides an opportunity to evaluate long-term data from patients receiving velaglucerase alfa. Results: This analysis included 376 treatment-naïve children and adults with GD enrolled in GOS, including 20 with type 3 GD, who initiated velaglucerase alfa through participation in clinical trials or as part of their clinical management and continued treatment for a mean (range) time of 6.6 (0.003-18.6) years. Initial improvements in hematologic and visceral parameters and the biomarkers glucosylsphingosine (lyso-GL1) and chitotriosidase were observed after one year of treatment and were maintained throughout the follow-up period. Of 129 (34.3%) patients who developed adverse events during the follow-up period, events were considered related to treatment in 33 (8.8%). None led to treatment discontinuation. There were 21 deaths overall, none of which were considered related to treatment. Conclusions: This analysis of data from the GOS registry supports the safety and efficacy of velaglucerase alfa in patients with GD.

FindZebra online search delving into rare disease case reports using natural language processing

Early diagnosis is crucial for well-being and life quality of the rare disease patient. Access to the most complete knowledge about diseases through intelligent user interfaces can play an important role in supporting the physician reaching the correct diagnosis. Case reports may offer information about heterogeneous phenotypes which often further complicate rare disease diagnosis. The rare disease search engine FindZebra.com is extended to also access case report abstracts extracted from PubMed for several diseases. A search index for each disease is built in Apache Solr adding age, sex and clinical features extracted using text segmentation to enhance the specificity of search. Clinical experts performed retrospective validation of the search engine, utilising real-world Outcomes Survey data on Gaucher and Fabry patients. Medical experts evaluated the search results as being clinically relevant for the Fabry patients and less clinically relevant for the Gaucher patients. The shortcomings for Gaucher patients mainly reflect a mismatch between the current understanding and treatment of the disease and how it is reported in PubMed, notably in the older case reports. In response to this observation, a filter for the publication date was added in the final version of the tool available from deep.findzebra.com/<disease> with <disease> = gaucher, fabry, hae (Hereditary angioedema).

Potential Binding Sites of Pharmacological Chaperone NCGC00241607 on Mutant β-Glucocerebrosidase and Its Efficacy on Patient-Derived Cell Cultures in Gaucher and Parkinson's Disease

Mutations in the GBA1 gene, encoding the lysosomal enzyme glucocerebrosidase (GCase), cause Gaucher disease (GD) and are the most common genetic risk factor for Parkinson's disease (PD). Pharmacological chaperones (PCs) are being developed as an alternative treatment approach for GD and PD. To date, NCGC00241607 (NCGC607) is one of the most promising PCs. Using molecular docking and molecular dynamics simulation we identified and characterized six allosteric binding sites on the GCase surface suitable for PCs. Two sites were energetically more preferable for NCGC607 and located nearby to the active site of the enzyme. We evaluated the effects of NCGC607 treatment on GCase activity and protein levels, glycolipids concentration in cultured macrophages from GD (n = 9) and GBA-PD (n = 5) patients as well as in induced human pluripotent stem cells (iPSC)-derived dopaminergic (DA) neurons from GBA-PD patient. The results showed that NCGC607 treatment increased GCase activity (by 1.3-fold) and protein levels (by 1.5-fold), decreased glycolipids concentration (by 4.0-fold) in cultured macrophages derived from GD patients and also enhanced GCase activity (by 1.5-fold) in cultured macrophages derived from GBA-PD patients with N370S mutation (p < 0.05). In iPSC-derived DA neurons from GBA-PD patients with N370S mutation NCGC607 treatment increased GCase activity and protein levels by 1.1-fold and 1.7-fold (p < 0.05). Thus, our results showed that NCGC607 could bind to allosteric sites on the GCase surface and confirmed its efficacy on cultured macrophages from GD and GBA-PD patients as well as on iPSC-derived DA neurons from GBA-PD patients.

High-Dose Ambroxol Therapy in Type 1 Gaucher Disease Focusing on Patients with Poor Response to Enzyme Replacement Therapy or Substrate Reduction Therapy

Ambroxol hydrochloride (ABX), an oral mucolytic drug available over the counter for many years, acts as a pharmacological chaperone for mutant glucocerebrosidase, albeit at higher doses. Proof-of-concept reports have been published over the past decade on all three types of Gaucher disease (GD). Here, we assess the safety and efficacy of 12 months of 600 mg ambroxol per day in three groups of Type 1 GD patients with a suboptimal response to enzyme replacement therapy (ERT) or substrate reduction therapy (SRT), defined as platelet count < 100 × 10³/L, lumbar spine bone density T-score < -2.0, and/or LysoGb1 > 200 ng/mL, and for a group of naïve patients who had abnormal values in two of these three parameters. We enrolled 40 patients: 28 ERT- or SRT-treated, and 12 naïve. There were no severe adverse effects (AEs). There were 24 dropouts, mostly due to AEs (n = 12), all transient, and COVID-19 (n = 7). Among the 16 completers, 5 (31.2%) had a >20% increase in platelet count, 6 (37.5%) had a >0.2 increase in T-score, and 3 (18.7%) had a >20% decrease in Lyso-Gb1. This study expands the number of patients exposed to high-dose ABX, showing good safety and satisfactory efficacy, and provides an additional rationale for adding off-label ABX to the arsenal of therapies that could be offered to patients with GD1 and a suboptimal response or those unable to receive ERT or SRT.

The Bone Biomarker of Quantitative Chemical Shift Imaging in Patients with Type 1 Gaucher Disease Receiving Low-Dose Long-Term Enzyme Replacement Therapy

Quantitative chemical shift imaging (QCSI) is the most sensitive imaging biomarker to assess bone marrow involvement in Gaucher disease. Widespread QCSI use is limited by test availability. Anecdotal reports describe two patients demonstrating significant improvement in fat fraction (FF) assessed by QCSI following a switch from imiglucerase to taliglucerase alfa. This analysis evaluated bone marrow involvement in adults with Type 1 Gaucher disease receiving low-dose enzyme replacement therapy (ERT) with imiglucerase and/or velaglucerase alfa. We report baseline data for 30 patients meeting eligibility criteria. Median (range) duration and dose of ERT were 18 (5–26) years and 30 (30–60) U/kg/month, respectively. Low FF scores (<0.30) were observed for seven patients (23%; 95% confidence interval, 10–42%) and were more common in females (n = 6) versus males (n = 1; p < 0.025); one female was menopausal. These baseline data demonstrate that prolonged low-dose ERT with imiglucerase or velaglucerase alfa led to an adequate bone response, assessed by QCSI, in the majority of patients. A minority of such patients with suboptimal bone response require therapeutic change. The next phase of the study will address the effect of switching to taliglucerase alfa on bone status for patients with less than optimal QCSI scores (<0.30).

A Systematic Review and Meta-analyses of Longitudinal Studies on Drug Treatments for Gaucher Disease

OBJECTIVE

Gaucher disease (GD) is a rare disorder linked to the absence/deficiency of glucocerebrosidase. GD can be treated by enzyme replacement therapy (ERT) and substrate reduction therapy (SRT). The aim of this systematic review (SR) is to assess the effectiveness of drugs used for GD treatment.

DATA SOURCES

Searches were conducted in PubMed and Scopus, in April 2021. The search strategies encompassed the name of the disease and of the drug treatments. Manual search was also conducted.

STUDY SELECTION AND DATA EXTRACTION

Observational and interventional longitudinal studies evaluating ERT and SRT for GD were included. Single mean meta-analyses were conducted for each drug using R.

DATA SYNTHESIS

The initial search retrieved 2246 articles after duplicates were removed. Following screening and eligibility assessment, 68 reports were included. The studies evaluated imiglucerase, velaglucerase alfa, taliglucerase alfa, miglustat, and eliglustat. The results showed that ERT is effective as a treatment in both naïve and experienced patients. Miglustat did not significantly improve blood outcomes in naïve patients and resulted in a decrease in the platelet levels of experienced patients. Eliglustat was mainly assessed for experienced patients and resulted in stable outcome values.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This extensive SR confirms the effectiveness of GD treatments in short- and long-term follow-ups.

CONCLUSIONS

The results were favorable for all ERTs and for eliglustat. Based on the assessed evidence, miglustat did not achieved expressive results. However, all evidence should be interpreted considering its limitations and does not replace well-conducted randomized trials.

The budget impact of enzyme replacement therapy in type 1 Gaucher disease in the United States

AIM

Gaucher disease (GD) is a rare autosomal recessive condition. Type 1 GD (GD1) is the most prevalent form of GD in Western countries; enzyme replacement therapy (ERT) is a treatment option for patients with GD1. To understand the economic value of the GD1 ERT velaglucerase alfa, a budget impact model (BIM) was developed from a United States (US) payer perspective.

METHODS

We estimated the budget impact of velaglucerase alfa for a 10-million-member US health plan by comparing the annual total costs of therapy between a scenario using current velaglucerase alfa uptake to a projected scenario with increased velaglucerase alfa uptake. Total drug costs for both scenarios were estimated as the sum of the product of the number of eligible patients on each treatment and the annual per-patient cost of each medication. Average per-patient costs for ERTs were calculated by adding the yearly drug acquisition, drug administration, and site-of-care markup costs. The budget impact was measured over years 1-3.

RESULTS

An estimated 65 patients would receive velaglucerase alfa treatment in year 1, increasing to 90 patients by year 3. Across analyses, cost savings were realized with velaglucerase alfa compared with imiglucerase ($115,909) and taliglucerase alfa ($80,401). An annual total budget savings of $8.67 million could be realized for a hypothetical 10-million-member US health plan with increased velaglucerase alfa uptake. The per-member per-month costs decreased by $0.0241 across years 1-3.

CONCLUSIONS

BIM results show that increased velaglucerase alfa uptake for GD1 treatment is cost-saving for US health plans.

Long-term safety and effectiveness of velaglucerase alfa in Gaucher disease: 6-year interim analysis of a post-marketing surveillance in Japan

BACKGROUND

Gaucher disease (GD) is caused by reduced lysosomal enzyme β-glucocerebrosidase activity. Heterogeneous genotypes and phenotypes have been observed within GD types and across ethnicities. Enzyme replacement therapy is generally recommended for patients with type 1 GD, the least severe form of GD. In Japan, velaglucerase alfa has a broad indication covering type 1, 2 or 3 GD.  METHODS: All patients with type 1, 2, or 3 GD administered velaglucerase alfa 60 U/kg every 2 weeks via intravenous infusion after its launch date in Japan in 2014, were enrolled in a non-interventional, observational post-marketing surveillance (PMS). Individual patient data were reported via case report forms (CRFs). Key safety endpoints investigated included the incidence of infusion-related reactions (IRRs), the safety of velaglucerase alfa in patients with types 2 and 3 GD, from patients under one year of age to elderly patients (≥ 65 years of age). Long-term efficacy was also assessed.  RESULTS: In total, 53 patients with GD were registered. CRFs were available for 41 (77.4%) patients at the 6-year interim analysis. Fourteen adverse drug reactions (ADRs) were reported in seven patients. All reported ADRs occurred in patients with type 2 GD. ADRs were reported by 63.6% (7/11) of patients with type 2 GD. Ten ADRs were reported in five patients aged < 4 years. No elderly patients experienced any ADR during the surveillance period. Five ADRs occurring in three (10.0%) patients were classified as IRRs, with one case of vomiting (moderate severity) resulting in treatment discontinuation. Ten serious adverse events were reported in five (16.7%) patients. Three fatal events were considered to be unrelated to treatment with velaglucerase alfa. Platelet counts increased after the administration of velaglucerase alfa and were generally maintained within the normal range over the administration period. Among eleven patients tested for neutralizing anti-velaglucerase alfa antibodies, two (18.2%) were assessed as positive results.  CONCLUSION: PMS data from patients with types 1-3 GD in Japan indicate that long-term treatment with velaglucerase alfa was well-tolerated and associated with increased platelet counts, which is consistent with observations made in studies outside of Japan.

TRIAL REGISTRATION

NCT03625882 registered July 2014.

Hematological manifestations and complications of Gaucher disease

Introduction: Gaucher disease (GD), although pan-ethnic and rare (common in Ashkenazi Jews), is of great importance to hematologists both for diagnosis and management. The need for increased awareness of GD is that delayed diagnosis may lead to preventable irreversible complications (mainly skeletal) or unnecessary invasive procedures (e.g. bone marrow biopsy), and the birth of another affected sibling due to lack of genetic consulting.Areas covered: The review outlines the common hematological manifestations of GD, including splenomegaly, thrombocytopenia, and anemia. Other hematological manifestations such as coagulation abnormalities, platelet dysfunction, gammopathy, and other hematological malignancies associated with GD are also discussed. Current and future treatment modalities are delineated, including enzyme replacement and substrate reduction therapy, pharmacological chaperon, and gene therapy. A literature search was conducted to identify original research articles relevant to hematology manifestations and GD published before November 2020.Expert opinion: Patients with GD should be ideally followed and treated in a center of excellence where the GD expert benefits from experienced consultants in relevant disciplines. Due to the availability of several very expensive treatment options, it is important to have an unbiased expert who can select the most suitable management for the individual patients (including withholding prescription in asymptomatic patients).

A charitable access program for patients with lysosomal storage disorders in underserved communities worldwide

Background

Lysosomal storage disorders (LSDs) are rare genetic disorders, with heterogeneous clinical manifestations and severity. Treatment options, such as enzyme replacement therapy (ERT), substrate replacement therapy, and pharmacological chaperone therapy, are available for several LSDs, including Gaucher disease (GD), Fabry disease (FD), and Hunter syndrome (mucopolysaccharidosis type II [MPS II]). However, patients in some countries face challenges accessing treatments owing to limited availability of locally licensed, approved drugs.

Methods

The Takeda LSD Charitable access program aims to meet the needs of individuals with GD, FD or MPS II with the greatest overall likelihood of benefit, in selected countries, through donation of ERT to nonprofit organizations, and support for medical capacity-building as well as family support via independent grants. Long-term aims of the program are to establish sustainable healthcare services delivered by local healthcare providers for patients with rare metabolic diseases. Patients receiving treatment through the program are monitored regularly, and their clinical data and progress are reviewed annually by an independent medical expert committee (MEC). The MEC also selects patients for enrollment completely independent from the sponsoring company.

Results

As of 31 August, 2019, 199 patients from 13 countries were enrolled in the program; 142 with GD, 41 with MPS II, and 16 with FD. Physicians reported improvements in clinical condition for 147 (95%) of 155 patients with follow-up data at 1 year.

Conclusions

The response rate for follow-up data at 1 year was high, with data collected for > 90% of patients who received ERT through the program showing clinical improvements in the majority of patients. These findings suggest that the program can benefit selected patients previously unable to access disease-specific treatments. Further innovative solutions and efforts are needed to address the challenges and unmet needs of patients with LSDs and other rare diseases around the world.

How we manage Gaucher Disease in the era of choices

Treatment of Gaucher Disease (GD) is now beset with the abundance of therapeutic options for an individual patient, making the choice of therapy complex for both expert and non-expert clinicians. The pathogenesis of all disease manifestations is a gene mutation-driven deficiency of glucocerebrosidase, but the clinical expression and response of each of the clinical manifestations to different therapies can be difficult to predict. Enzyme replacement therapy has been available since 1991 and is well-established, with known efficacy and minimal toxicity. Of interest, the three available enzymes are distinct molecules and were registered as new products, not biosimilars. Oral substrate reduction therapy has undergone a revitalisation with a newly approved agent in this class for which some efficacy and toxicity questions have been raised. Herein we present our approach to the management of GD in the era of choices, including a new algorithm for how to manage a newly diagnosed patient.

Demographics and patient characteristics of 1209 patients with Gaucher disease: Descriptive analysis from the Gaucher Outcome Survey (GOS)

The Gaucher Outcome Survey (GOS) is an international Gaucher disease (GD) registry established in 2010 for patients with a confirmed GD diagnosis, regardless of GD type or treatment status, designed to evaluate the safety and long‐term effectiveness of velaglucerase alfa and other GD‐related treatments. As of February 25, 2017, 1209 patients had enrolled, the majority from Israel (44.3%) and the US (31.4%). Median age at GOS entry was 40.4 years, 44.1% were male, and 13.3% had undergone a total splenectomy. Most patients had type 1 GD (91.5%) and were of Ashkenazi Jewish ethnicity (55.8%). N370S/N370S was the most prevalent genotype, accounting for 44.2% of genotype‐confirmed individuals (n = 847); however, there was considerable variation between countries. A total of 887 (73.4%) patients had received ≥1 GD‐specific treatment at any time, most commonly imiglucerase (n = 587), velaglucerase alfa (n = 507), and alglucerase (n = 102). Hematological and visceral findings at the time of GOS entry were close to normal for most patients, probably a result of previous treatment; however, spleen volume of patients in Israel was almost double that of patients elsewhere (7.2 multiples of normal [MN] vs. 2.7, 2.9 and 4.9 MN in the US, UK and rest of world), which may be explained by a greater disease severity in this cohort. This analysis aimed to provide an overview of GOS and present baseline demographic and disease characteristics of participating patients to help improve the understanding of the natural history of GD and inform the overall management of patients with the disease.