Real-World Safety, Effectiveness, and Patient-Reported Outcomes in Patients with Chronic Hepatitis C Virus Infection Treated with Glecaprevir/Pibrentasvir: Updated Data from the German Hepatitis C-Registry (DHC-R)

Using data from the German Hepatitis C-Registry (Deutsche Hepatitis C-Register, DHC-R), we report the real-world safety and effectiveness of glecaprevir/pibrentasvir (GLE/PIB) treatment and its impact on patient-reported outcomes (PROs) in underserved populations who are not typically included in clinical trials, yet who will be crucial for achieving hepatitis C virus (HCV) elimination. The DHC-R is an ongoing, non-interventional, multicenter, prospective, observational cohort study on patients treated for chronic HCV infection in Germany. The data cutoff was 17 January 2021. The primary effectiveness endpoint was sustained virologic response at post-treatment Week 12 (SVR12). Safety outcomes were assessed in all patients receiving GLE/PIB. PROs were assessed using the SF-36 survey. Of 2354 patients, 1964 had valid SVR12 data (intention-to-treat analysis). Of these, 1905 (97.0%) achieved SVR12 with rates similar across the comorbidities analyzed, except for people who actively use drugs (PWUD (active)) (86.4%). Excluding those who discontinued treatment and did not achieve SVR12, or were reinfected with HCV, the rate was 99.3%, with similar results regardless of comorbidity. PWUD (active) and those with psychiatric disorders had the most meaningful improvements in PROs. Adverse events (AEs) occurred in 631/2354 patients (26.8%), and serious AEs in 44 patients (1.9%). GLE/PIB was highly effective and well tolerated in this real-world study of patient groups key to HCV elimination.

The changing characteristics of patients infected with chronic hepatitis C virus from 2014 to 2019: Real-world data from the German Hepatitis C-Registry (DHC-R)

The number of patients diagnosed with hepatitis C virus (HCV) is markedly higher than the number initiating treatment indicating gaps in the care cascade, likely centred around reaching at-risk populations. Understanding changing characteristics of patients with HCV allows for targeted programs that increase linkage to care. We investigated changes in demographic and clinical characteristics of patients registered in the German Hepatitis C-Registry (DHC-R) from 1 January 2014 to 31 December 2019. The DHC-R is an ongoing, noninterventional, multicentre, prospective, observational cohort registry including 327 German centres. Patient characteristics were analysed over time in 7 phases for all patients completing a screening visit. Overall, 14,357 patients were enrolled. The percentage of treatment-naïve/non-cirrhotic patients increased from 34.4% in phase 1 (1 January-31 December 2014) to 68.2% in phase 7 (1 August-31 December 2019). The proportion of migrants, alcohol users, people who inject drugs, and those receiving opiate substitution therapy increased in later registry phases. Most patients (60.1%) were receiving comedication at baseline. The most prescribed comedications were drugs used to treat opioid dependence which increased from 9.2% in phase 1 to 24.0% in phase 7. The patients' mean age decreased from 52.3 years in phase 1 to 48.7 years in phase 7. From 2014 to 2019, the proportion of at-risk patients enrolling in the registry increased. To eliminate viral hepatitis as a major public health threat, a continued commitment to engaging underserved populations into the HCV care cascade is needed.

Glecaprevir/pibrentasvir for 8 weeks in patients with compensated cirrhosis: Safety and effectiveness data from the German Hepatitis C-Registry

Glecaprevir/pibrentasvir, a pangenotypic, direct-acting antiviral combination approved for chronic hepatitis C virus treatment, has limited real-world evidence supporting 8-week therapy in compensated cirrhosis. We investigated effectiveness and safety of 187 hepatitis C virus-infected, treatment-naïve, patients with compensated cirrhosis receiving 8-week glecaprevir/pibrentasvir therapy in the German Hepatitis C-Registry between 2 August 2017 and 1 January 2020. Sustained virologic response was 98.4% (127/129) in the per-protocol analysis (excluding patients lost to follow-up or who discontinued treatment due to compliance) and was 85.8% (127/148) in patients with data available in an intention-to-treat analysis. Nineteen patients were lost to follow-up; nine genotype 3 patients, nine nongenotype 3 patients and one mixed genotype patient. One patient relapsed, and one died, unrelated to treatment. Adverse events (>5%) were fatigue and headache. Two serious adverse events occurred; no adverse events resulted in drug discontinuation. An 8-week glecaprevir/pibrentasvir therapy was effective and well-tolerated in this real-world analysis.

Hepatitis C virus: Current steps toward elimination in Germany and barriers to reaching the 2030 goal

Hepatitis C virus (HCV) affects over 70 million people globally, with an estimated 399 000 HCV-related deaths in 2016. The World Health Organization (WHO) has set a goal to eliminate HCV by 2030. Despite the availability of direct-acting antivirals-highly effective and well-tolerated therapies for HCV-many patients infected with HCV in Germany have not initiated treatment, including a majority of those who are aware of their positive diagnosis. Barriers to screening, diagnosis, and treatment are major factors taking many countries off track for HCV elimination by 2030. Identifying country-specific barriers and challenges, particularly in at-risk populations such as people who inject drugs or men who have sex with men, has the potential to create tailored programs and strategies to increase access to screening or treatment and engage at-risk populations. This review aims to report the current steps toward HCV elimination in Germany, the country-specific barriers and challenges that will potentially prevent reaching the 2030 HCV elimination goal and describe good practice examples to overcome these barriers.

Glecaprevir/pibrentasvir is safe and effective in hepatitis C patients with cirrhosis: Real-world data from the German Hepatitis C-Registry

Glecaprevir/pibrentasvir is a pangenotypic direct-acting antiviral regimen approved for treating chronic hepatitis C virus. Real-world use of protease-inhibitor-containing regimens requires further evaluation in patients with cirrhosis. We evaluated the real-world safety and effectiveness of glecaprevir/pibrentasvir in patients with cirrhosis from the German Hepatitis C-Registry who initiated treatment between 2 August 2017 and 30 June 2019. Overall, 131 patients received 12-week (on-label) treatment and 51 received 8-week (off-label) treatment. No patient discontinued treatment due to adverse events. Four patients had serious adverse events; none were considered related to glecaprevir/pibrentasvir. Two patients had total bilirubin > 5 × upper limit of normal (ULN) during treatment. Three patients had alanine aminotransferase and three patients had aspartate aminotransferase > 3 × ULN. Rates of sustained virologic response were 100% (86/86) for 86 patients with available data. Glecaprevir/pibrentasvir treatment was well-tolerated and highly effective in patients with chronic hepatitis C and cirrhosis in real-world practice.

Real-world effectiveness and safety of glecaprevir/pibrentasvir for the treatment of chronic hepatitis C infection: data from the German Hepatitis C-Registry

BACKGROUND

Glecaprevir/pibrentasvir is a pangenotypic direct-acting antiviral regimen approved for treating adults chronically infected with hepatitis C virus (HCV). There are limited real-world data on glecaprevir/pibrentasvir to date.

AIM

To evaluate the effectiveness and safety of glecaprevir/pibrentasvir under real-world conditions in the German Hepatitis C-Registry (DHC-R).

METHODS

The DHC-R is an ongoing, non-interventional, multicentre, prospective, observational cohort study that monitors patients with chronic HCV infection. Data were collected from patients who initiated glecaprevir/pibrentasvir and completed a screening visit on or after 2 August 2017. The primary effectiveness endpoint was sustained virological response at post-treatment Week 12 (SVR12). Safety and tolerability were also assessed.

RESULTS

As of 15 July 2018, 586 patients received glecaprevir/pibrentasvir and had documented SVR12 data, treatment discontinuation, loss to follow-up or HCV reinfection. Five hundred and fifty-two patients (94%) received on-label treatment. At baseline, most on-label patients were infected with HCV genotype 1 (53%) or 3 (33%), HCV treatment-naïve (90%), without cirrhosis (94%), and treated for 8 weeks (93%). Five hundred and thirty-four patients (96.7%) achieved SVR12 (intention-to-treat [ITT] analysis). By modified ITT analysis (excluding patients who discontinued and did not achieve SVR12 or patients lost to follow-up), the SVR12 rate was 99.4% (n/N = 534/537). There was one documented virological failure (relapse) and two documented HCV reinfections. One hundred and forty-two (26%) adverse events (AEs) and 9 (2%) serious AEs occurred; 2 (<1%) AEs led to treatment discontinuation. All patients treated off-label (N = 34) achieved SVR12.

CONCLUSION

Glecaprevir/pibrentasvir was highly effective and well tolerated under real-world conditions. Clinical trial number: DRKS00009717 (German Clinical Trials Register, DRKS).

1981. Real-World Data on Safety and Effectiveness of Glecaprevir/Pibrentasvir for the Treatment of Patients With Chronic Hepatitis C Virus Infection on Opioid Substitution Therapy: Latest Results from the German Hepatitis C-Registry

Background

The coformulated direct-acting antivirals glecaprevir/pibrentasvir (G/P) are approved to treat chronic hepatitis C virus (HCV) genotype 1–6 infection. In clinical trials, G/P demonstrated high efficacy, but real-world data in patients on opioid substitution therapy (OST), a population for which antiviral treatment is critical for HCV elimination, are limited. Here we report the first real-world data on the effectiveness and safety of G/P for OST patients within the German Hepatitis C-Registry (DHC-R).

Methods

The DHC-R is an ongoing, noninterventional, multicenter, prospective, monitored registry study. Data were collected between July 28, 2017 and February 9, 2018 from 104 sites in Germany. The analysis included adult HCV-infected patients who were treated with G/P according to the European Medicines Agency label. The primary endpoint was sustained virologic response at post-treatment week 12 (SVR12). Safety and tolerability were assessed in patients that completed treatment.

Results

As of February 9, 2018, 638 patients had initiated on-label treatment with G/P and are included in the baseline analysis. Patients on OST comprised 26% (168/638) of the baseline population, of which most patients were treatment-naive, without cirrhosis and had HCV genotype 1a or 3. Among patients with available SVR12 data, 96% (27/28) of OST patients and 97% (66/68) of non-OST patients achieved SVR12. There were no virologic failures: of three early discontinuations, one OST patient was lost to follow-up and two non-OST patients discontinued treatment due to adverse events (AE). In the modified intention-to-treat population which excluded non-virologic failures, SVR12 was 100% for both OST and non-OST patients. The safety population included 321 patients in total. Among OST patients, 2% (2/84) experienced serious AEs (SAE) without any treatment discontinuations due to AE/SAE.

Conclusion

In this real-world analysis, G/P treatment yielded favorable effectiveness and safety results in patients on OST. Updated data and SVR12 results will be presented.

Disclosures

J. Reimer, AbbVie, Bristol-Myers Squibb, Gilead, Janssen-Cilag, MSD: Board Member and Scientific Advisor, Educational grant and Speaker honorarium. A. Stoehr, AbbVie, Gilead, Janssen, MSD, ViiV: Consultant and Scientific Advisor, Consulting fee and Speaker honorarium. U. Naumann, AbbVie, Bristol-Myers Squibb, Gilead Sciences, Janssen, Mundipharma, MSD, Roche, ViiV: Board Member, Scientific Advisor and Speaker’s Bureau, Consulting fee and Speaker honorarium. G. Teuber,: AbbVie, BMS, Janssen, Gilead, MSD: Consultant and Scientific Advisor, Consulting fee and Speaker honorarium. C. Zamani, AbbVie Inc.: Board Member and Scientific Advisor, Consulting fee. S. Mauss, AbbVie, Gilead, Falk, Janssen, MSD: Scientific Advisor and Speaker’s Bureau, Consulting fee and Speaker honorarium. N. Qurishi, AbbVie, Gilead, Janssen, MSD, ViiV, Mundipharma, Hexal: Consultant and Scientific Advisor, Consulting fee and Speaker honorarium. K. Lohmann, AbbVie Inc.: Employee and Shareholder, Salary and Stock and/or options. H. Kleine, AbbVie Inc.: Employee and Shareholder, Salary and Stock and/or options. A. Pangerl, AbbVie Inc.: Employee and Shareholder, Salary and Stock and/or options. S. Christensen, AbbVie, Gilead, Indivior, Janssen-Cilag, MSD, ViiV: Consultant and Scientific Advisor, Consulting fee and Speaker honorarium.

Zusammenhänge zwischen Konstitution und Wirkung bei Hemmstoffen der Fibrinolyse

Die antifibrinolytische Aktivität der e-Aminocapronsäure ist an ihre freie Aminound Carboxylgruppe und an den Abstand dieser beiden Gruppen voneinander gebunden. Substitutionen an beiden Gruppen oder Veränderungen ihres Abstandes führen zu einer Verminderung der antifibrinolytischen Aktivität. Zyklische Verbindungen sind ebenfalls antifibrinolytisch aktiv, wenn sie eine terminale Aminound Carboxylgruppe in einem entsprechenden Abstand voneinander besitzen. Derartige Verbindungen sind die p-Aminomethylbenzoesäure und ihre hydrierte Form, die 4-Aminomethylcyclohexancarbonsäure-(l), wobei sich die p-Aminomethylbenzoesäure (PAMBA) als die stärkste der bisher bekannten antifibrinolytisch wirksamen Substanzen erwies. Ihre Wirkung beruht auf einer Blockade der Plasminogenaktivierung.

Multicenter study of radiosynoviorthesis

Aim: Evaluation of the effectiveness of radiosynoviorthesis (RSO) in osteoarthritis and other disorders with concomitant synovitis versus rheumatoid arthritis by means of a standardized questionnaire. Patients, methods: 803 RSO treatments were monitored in 691 patients by standardized questionnaires of 7 centers in 3 countries. Patients were assigned to 3 groups according to their age (20-40, 41-60, 61-80 years). Additionally, the data were analyzed separately for patients with rheumatoid arthritis (group A) and those with osteoarthritis, psoriasis arthritis, pigmental villonodular synovitis or persistent effusions after joint replacement (group B). Results: Ameliorations of joint pain, swelling/effusion or flexibility were found in 80% of group A and 56% of group B (p <0.01). Quality of life improved in 78% of group A and 59% of group B (p <0.01). The response rate was similar for small- and large-sized joints in group A, but significantly higher for large-sized joints in group B (p <0.01). The positive effects on joint pain, swell-ing/effusion or flexibility lasted longer in group A (p <0.01). Repeated RSOs were as effective as initial ones. The clinical outcome was neither influenced by age, nor gender, nor transient immobilisation for 48 hours after RSO. Conclusion: Although slightly more efficient in rheumatoid arthritis, RSO represents an effective treatment option also in osteoarthritis and other disorders with concomitant synovitis.

[Genetic risk variants in Parkinson's disease and other movement disorders]

Movement disorders are often genetically complex with genetic risk factors playing a major role. For example, monogenic causes of Parkinson's disease (PD) can be found in only 2-5% of patients who often have an early onset (<40 years). In the majority of patients, common genetic variants seem to contribute to the disease risk. To date, 24 genetic risk factors have been identified. For restless legs syndrome (RLS), six different risk variants have been reported but no monogenic cause is known yet. For the genetic risk factors of essential tremor and dystonia, which are less well studied, only five and two candidate variants, respectively, have been described but their roles still require independent confirmation. In this review, we provide an overview on the involved genes, their function, and discuss possible, disease mechanism-driven therapies.

More than just crushing: a prospective pre-post intervention study to reduce drug preparation errors in patients with feeding tubes

WHAT IS KNOWN AND OBJECTIVES

Incorrect drug preparation for patients with feeding tubes can result in harm for the patient and the preparing person. Combined intervention programs are effective tools to reduce such preparation errors. However, to date, intervention programs have been mostly tested in hospitals with computerized physician order entry (CPOE), unit-dose systems, or ward-based clinical pharmacists. Hence, the primary objective of this study was to develop and evaluate an intervention program tailored to hospitals without such preconditions.

METHODS

We conducted a prospective pre-/post-intervention study on a gastroenterological intensive care unit (ICU) and a surgical ward for oral, dental and maxillofacial diseases (surgical ward). During the study periods, observers documented and evaluated drug preparation processes of all peroral drugs for patients with feeding tubes. The primary endpoint was the rate of inappropriately crushed and/or suspended solid peroral drugs in regards to all solid peroral drugs.

RESULTS AND DISCUSSION

Altogether, we evaluated 775 drug preparation processes of solid peroral drugs on the ICU and 975 on the surgical ward. The intervention program significantly reduced incorrect crushing and/or suspending of solid peroral drugs for administration to patients with feeding tubes from 9·8% to 4·2% (P < 0·01) on the ICU and from 5·7% to 1·4% (P < 0·01) on the surgical ward.

WHAT IS NEW AND CONCLUSION

The implementation of the newly developed intervention program significantly reduced the rate of inappropriately prepared solid peroral drugs, suggesting that it is an effective measure to enable safe drug administration for inpatients with feeding tubes.

Development of a standardized knowledge base to generate individualized medication plans automatically with drug administration recommendations

AIMS

We aimed to develop a generic knowledge base with drug administration recommendations which allows the generation of a dynamic and comprehensive medication plan and to evaluate its comprehensibility and potential benefit in a qualitative pilot study with patients and physicians.

METHODS

Based on a literature search and previously published medication plans, a prototype was developed and iteratively refined through qualitative evaluation (interviews with patients and focus group discussions with physicians). To develop the recommendations for safe administration of specific drugs we screened the summary of product characteristics (SmPC) of different exemplary brands, allocated the generated advice to groups with brands potentially requiring the same advice, and reviewed these allocations regarding applicability and appropriateness of the recommendations.

RESULTS

For the recommendations, 411 SmPCs of 140 different active ingredients including all available galenic formulations, routes of administrations except infusions, and administration devices were screened. Finally, 515 distinct administration recommendations were included in the database. In 926 different generic groups, 29,879 allocations of brands to general advice, food advice, indications, step-by-step instructions, or combinations thereof were made. Thereby, 27,216 of the preselected allocations (91.1%) were confirmed as appropriate. In total, one third of the German drug market was labelled with information.

CONCLUSIONS

Generic grouping of brands according to their active ingredient and other drug characteristics and allocation of standardized administration recommendations is feasible for a large drug market and can be integrated in a medication plan.

Safeguarding the process of drug administration with an emphasis on electronic support tools

AIMS

The aim of this work is to understand the process of drug administration and identify points in the workflow that resulted in interventions by clinical information systems in order to improve patient safety.

METHODS

To identify a generic way to structure the drug administration process we performed peer-group discussions and supplemented these discussions with a literature search for studies reporting errors in drug administration and strategies for their prevention.

RESULTS

We concluded that the drug administration process might consist of up to 11 sub-steps, which can be grouped into the four sub-processes of preparation, personalization, application and follow-up. Errors in drug handling and administration are diverse and frequent and in many cases not caused by the patient him/herself, but by family members or nurses. Accordingly, different prevention strategies have been set in place with relatively few approaches involving e-health technology.

CONCLUSIONS

A generic structuring of the administration process and particular error-prone sub-steps may facilitate the allocation of prevention strategies and help to identify research gaps.

[Genetics of movement disorders]

A number of genetic causes of movement disorders including Parkinson disease, dystonia, restless legs syndrome or essential tremor have been elucidated in recent years. This process was accelerated by novel technologies including genome-wide association studies (GWAS) and next generation sequencing (NGS). Although monogenic forms are overall rare, they provide a unique opportunity to investigate mutation carriers who are still in the presymptomatic phase. As these subjects present individuals at risk to develop the disease, they have been included in longitudinal studies to unravel disease mechanisms and elucidate novel therapeutic targets. In addition, cell culture and animal studies have been performed to functionally characterize proteins mutated in different movement disorders to provide further insight into disturbed cellular pathways. In this article, we summarize known monogenic forms and the associated phenotype as well as genetic risk factors and review the function of relevant genes and proteins.

Autosomal dominant Parkinson's disease in a large German pedigree

OBJECTIVE

While several genes have been identified to cause Parkinson's disease (PD), monogenic forms explain only a small proportion of cases. We report clinical and genetic results in a large family with late-onset autosomal dominant PD.

METHODS

Thirty-eight family members of a five-generation Northern German PD family underwent a detailed neurologic examination, and transcranial sonography was performed in fifteen of them. Comprehensive mutation analysis of known PD-causing genes and a genome-wide linkage analysis were performed.

RESULTS

Late-onset definite PD was found in five subjects with a mean age at onset of 63 years. Another six individuals presented either with probable/possible PD or with subtle parkinsonian signs. Six members with a mean age of 79 years had an essential tremor phenotype. Mode of PD inheritance was compatible with autosomal dominant transmission. One of three examined patients with definite PD demonstrated an increased area of substantia nigra hyperechogenicity upon transcranial sonography. Comprehensive linkage and mutational analysis excluded mutations in known PD-causing genes. Genome-wide linkage analysis suggested a putative disease gene in an 11.3-Mb region on chromosome 7p15-21.1 with a multipoint LOD score of 2.0.

CONCLUSIONS

The findings in this family further demonstrate genetic heterogeneity in familial autosomal dominant late-onset PD.

Glucocerebrosidase mutations in a Serbian Parkinson's disease population

BACKGROUND AND PURPOSE

To screen for glucocerebrosidase (GBA) mutations in a Serbian Parkinson's disease (PD) population.

METHODS

Glucocerebrosidase exons 8-11 harbouring the most common mutations were sequenced in 360 patients with PD and 348 controls from Serbia. Haplotype analysis was performed for the N370S mutation and compared with German and Ashkenazi Jewish carriers.

RESULTS

Glucocerebrosidase mutations were significantly more frequent in patients with PD (21/360; 5.8%) vs. controls (5/348; 1.4%; OR = 4.25; CI, 1.58-11.40; P = 0.0041). Two patients with PD carried homozygous or compound heterozygous mutations in GBA. The N370S mutation accounted for about half of the mutated alleles in patients (10/23) but was absent amongst controls. Three novel variants were detected including two non-synonymous variants (D380V, N392S) in the patient group and one synonymous change (V459V) in a control. Carriers of the D409H mutation were also sequenced for H255Q, and all were found to carry the [D409H; H255Q] double-mutant allele. Genotyping suggested a common haplotype for all N370S carriers.

CONCLUSION

Glucocerebrosidase mutations represent a PD risk factor in the Serbian population.

Nasal shedding of equine herpesvirus-1 from horses in an outbreak of equine herpes myeloencephalopathy in Western Canada

BACKGROUND

There is little information on the duration of nasal shedding of EHV-1 from horses with naturally occurring equine herpesvirus myeloencephalopathy (EHM).

OBJECTIVES

To evaluate the duration of nasal shedding of EHV-1 in horses affected by EHM.

ANIMALS

One hundred and four horses naturally exposed to EHV-1, 20 of which had clinical signs of EHM.

METHODS

All horses on affected premises were monitored. Those horses developing EHM were sampled in a longitudinal outbreak investigation. Nasal swabs were collected daily from 16 of 20 horses affected by EHM. A qPCR was performed on 98 of 246 nasal swab samples to determine nasal shedding duration. Historical and clinical information was analyzed to evaluate potential risk factors for developing EHM and duration of shedding during this outbreak.

RESULTS

The last day shedding was detected in any horse was Disease Day 9. EHV-1 was detected in two-thirds of horses tested on Disease Days 0-3. The amount of EHV-1 DNA found in nasal swabs varied markedly and was not associated with disease severity or age. The odds of developing EHM were greater for febrile horses (OR = 20.3; 95% CI 3.4-390.3; P = .01) as well as for horses attending the riding clinic (OR = 4.1; 95% CI 0.84-21.65; P = .08).

CONCLUSIONS AND CLINICAL IMPORTANCE

Biosecurity measures should be implemented for a minimum of 14 days beyond the onset of clinical signs of EHM. Animal managers cannot rely on the severity of clinical signs to predict the duration of EHV-1 shedding.

Etiology of musician's dystonia: familial or environmental?

OBJECTIVE

To test the hypothesis that there is familial aggregation of dystonia and other movement disorders in relatives of patients with musician's dystonia (MD) and to identify possible environmental triggers.

METHODS

The families of 28 index patients with MD (14 with a reported positive family history of focal task-specific dystonia [FTSD] and 14 with no known family history [FH-]) underwent a standardized telephone screening interview using a modified version of the Beth Israel Dystonia Screen. Videotaped neurologic examinations were performed on all participants who screened positive and consensus diagnoses established. All patients were investigated for DYT1 dystonia and suitable families were tested for linkage to DYT7. All family members were administered questionnaires covering potential triggers of FTSD.

RESULTS

A diagnosis of dystonia was established in all 28 index patients and in 19/97 examined relatives (MD: n = 8, other FTSD: n = 9, other dystonias: n = 2), 5 of whom were members of FH- families. In 27 of the 47 affected individuals, additional forms of dystonia were seen; other movement disorders were observed in 23 patients. In total, 18 families were multiplex families with two to four affected members. Autosomal dominant inheritance was compatible in at least 12 families. The GAG deletion in DYT1 was absent in all patients. Linkage to DYT7 could be excluded in 1 of the 11 informative families. With respect to potential environmental triggers, there was no significant difference between patients with MD/FTSD compared to unaffected family members.

CONCLUSION

Our results suggest a genetic contribution to musician's dystonia with phenotypic variability including focal task-specific dystonia.