Ammonium tetrathiomolybdate in the decoppering phase treatment of Wilson's disease with neurological symptoms: A case series

A systematic two-sample and bidirectional MR process highlights a unidirectional genetic causal effect of allergic diseases on COVID-19 infection/severity

BACKGROUND

Allergic diseases (ADs) such as asthma are presumed risk factors for COVID-19 infection. However, recent observational studies suggest that the assumed correlation contradicts each other. We therefore systematically investigated the genetic causal correlations between various ADs and COVID-19 infection/severity.

METHODS

We performed a two-sample, bidirectional Mendelian randomization (MR) study for five types of ADs and the latest round of COVID-19 GWAS meta-analysis datasets (critically ill, hospitalized, and infection cases). We also further validated the significant causal correlations and elucidated the potential underlying molecular mechanisms.

RESULTS

With the most suitable MR method, asthma consistently demonstrated causal protective effects on critically ill and hospitalized COVID-19 cases (OR < 0.93, p < 2.01 × 10-2), which were further confirmed by another validated GWAS dataset (OR < 0.92, p < 4.22 × 10-3). In addition, our MR analyses also observed significant causal correlations of food allergies such as shrimp allergy with the risk of COVID-19 infection/severity. However, we did not find any significant causal effect of COVID-19 phenotypes on the risk of ADs. Regarding the underlying molecular mechanisms, not only multiple immune-related cells such as CD4+ T, CD8+ T and the ratio of CD4+/CD8+ T cells showed significant causal effects on COVID-19 phenotypes and various ADs, the hematology traits including monocytes were also significantly correlated with them. Conversely, various ADs such as asthma and shrimp allergy may be causally correlated with COVID-19 infection/severity by affecting multiple hematological traits and immune-related cells.

CONCLUSIONS

Our systematic and bidirectional MR analyses suggest a unidirectional causal effect of various ADs, particularly of asthma on COVID-19 infection/severity, but the reverse is not true. The potential underlying molecular mechanisms of the causal effects call for more attention to clinical monitoring of hematological cells/traits and may be beneficial in developing effective therapeutic strategies for allergic patients following infection with COVID-19.

Early neurological deterioration in Wilson's disease: a systematic literature review and meta-analysis

INTRODUCTION

Neurological deterioration, soon after anti-copper treatment initiation, is problematic in the management of Wilson's disease (WD) and yet reports in the literature are limited. The aim of our study was to systematically assess the data according to early neurological deteriorations in WD, its outcome and risk factors.

METHODS

Using PRISMA guidelines, a systematic review of available data on early neurological deteriorations was performed by searching the PubMed database and reference lists. Random effects meta-analytic models summarized cases of neurological deterioration by disease phenotype.

RESULTS

Across the 32 included articles, 217 cases of early neurological deterioration occurred in 1512 WD patients (frequency 14.3%), most commonly in patients with neurological WD (21.8%; 167/763), rarely in hepatic disease (1.3%; 5/377), and with no cases among asymptomatic individuals. Most neurological deterioration occurred in patients treated with d-penicillamine (70.5%; 153/217), trientine (14.2%; 31/217) or zinc salts (6.9%; 15/217); the data did not allow to determine if that reflects how often treatments were chosen as first line therapy or if the risk of deterioration differed with therapy. Symptoms completely resolved in 24.2% of patients (31/128), resolved partially in 27.3% (35/128), did not improve in 39.8% (51/128), with 11 patients lost to follow-up.

CONCLUSIONS

Given its occurrence in up to 21.8% of patients with neurological WD in this meta-analysis of small studies, there is a need for further investigations to distinguish the natural time course of WD from treatment-related early deterioration and to develop a standard definition for treatment-induced effects.

Analyzing the Therapeutic Efficacy of Bis-Choline-Tetrathiomolybdate in the Atp7b-/- Copper Overload Mouse Model

Bis-choline-tetrathiomolybdate, introduced as WTX101 (now known as ALXN1840), is a first-in-class copper-protein-binding agent for oral therapy of Wilson’s disease. In contrast to other decoppering agents such as trientine or D-penicillamine it acts by forming a tripartite complex with copper and albumin, thereby detoxifying excess liver and blood copper through biliary excretion. Preclinical animal experimentation with this drug was typically done with the alternative ammonium salt of tetrathiomolybdate, which is expected to have identical properties in terms of copper binding. Here, we comparatively analyzed the therapeutic efficacy of ALXN1840, D-penicillamine and trientine in lowering hepatic copper content in Atp7b^−/− mouse. Liver specimens were subjected to laser ablation inductively conductively plasma mass spectrometry and electron microscopic analysis. We found that ALXN1840 caused a massive increase of hepatic copper and molybdenum during early stages of therapy. Prolonged treatment with ALXN1840 reduced hepatic copper to an extent that was similar to that observed after administration of D-penicillamine and trientine. Electron microscopic analysis showed a significant increase of lysosomal electron-dense particles in the liver confirming the proposed excretory pathway of ALXN1840. Ultrastructural analysis of mice treated with dosages comparable to the bis-choline-tetrathiomolybdate dosage used in an ongoing phase III trial in Wilson’s disease patients, as well as D-penicillamine and trientine, did not show relevant mitochondrial damage. In contrast, a high dose of ALXN1840 applied for four weeks triggered dramatic structural changes in mitochondria, which were notably characterized by the formation of holes with variable sizes. Although these experimental results may not be applicable to patients with Wilson’s disease, the data suggests that ALXN1840 should be administered at low concentrations to prevent mitochondrial dysfunction and overload of hepatic excretory pathways.

Safety profile of D-penicillamine: a comprehensive pharmacovigilance analysis by FDA adverse event reporting system

BACKGROUND

D-penicillamine (D-pen) is a copper-chelating drug and has immune-modulatory properties. D-pen is used to treat rheumatoid arthritis, Wilson's disease, and kidney stones (cystinuria). However, associated adverse events (AEs) of D-pen treatment are frequent and often serious. Therefore, a comprehensive assessment of the safety profile of D-pen is urgently needed.

RESEARCH DESIGN AND METHODS

We identified and analyzed AEs associated with D-pen between April-1970 to July-2020 from the U.S. Food and Drug Administration Adverse Event Reporting System (FAERS) databases and calculated the reported odds ratio (ROR) with 95% confidence intervals (CI) using the disproportionality analysis.

RESULTS

A total of 9,150,234 AEs related to drugs were reported in the FAERS database, of which 542 were related to D-Pen. We report that D-pen was associated with dystonia (ROR: 20.52; 95%CI: 12.46-33.80), drug hypersensitivity (ROR: 5.42; 95%CI: 3.72-7.90), pancytopenia (ROR: 10.20; 95%CI: 5.61-18.56), joint swelling (ROR: 9.07; 95%CI: 5.51-14.94), renal-impairment (ROR: 6.68; 95%CI: 3.67-12.15), dysphagia (ROR: 5.05; 95%CI: 2.76-8.89), aggravation of condition (ROR: 4.16; 95%CI: 2.60-6.67), congestive cardiac failure (ROR: 4.04; 95%CI: 2.22-7.35), peripheral edema (ROR: 3.77; 95%CI: 2.17-6.55), tremor (ROR: 3.46; 95%CI: 2.00-6.01), pyrexia (ROR: 3.46; 95%CI: 2.00-6.01), and gait disturbance (ROR: 2.41; 95%CI: 1.29-4.52).

CONCLUSIONS

Patients taking D-pen require close monitoring of renal function, blood counts, immunity, liver, cardiac function, and neurological function. D-pen suppresses immune system which maximizes the risk of infection.

Ammonium tetrathiomolybdate in the decoppering phase treatment of Wilson's disease with neurological symptoms: A case series

OBJECTIVES

To present our experience with ammonium tetrathiomolybdate (ATTM) in the decoppering phase treatment of Wilson's disease (WD) with neurological symptoms.

METHODS

An uncontrolled longitudinal study was carried out to describe a case series of five patients diagnosed of WD with neurological symptoms in our hospital over the last 5 years and receiving ATTM for 8 (or 16) weeks. Unified Wilson's Disease Rating Scale (UWDRS), Global Assessment Scale (GAS) for WD and the Brewer-adapted Unified Huntington's Disease Rating Scale (UHDRS) for WD, magnetic resonance imaging, and monitoring for potential adverse effects were carried out in all patients before starting ATTM and 3 months later when ATTM was stopped and zinc treatment was initiated.

RESULTS

All five patients presented neurological clinical improvement in UWDRS, GAS, and Brewer-adapted UHDRS for WD. Neuroimaging improvement was present in 2/5 patients with brain edema reduction. Mild anemia, leukopenia, and elevation of transaminases were detected in 1 patient, with complete remission after stopping ATTM for 1 week and then restarting at a half dose.

CONCLUSION

ATTM could be a good treatment for the initial treatment of WD with neurological symptoms due to its high efficacy, with a lower rate of neurological deterioration than the drugs currently available, despite the potential adverse effects.