Safety and efficacy of cerliponase alfa in children with neuronal ceroid lipofuscinosis type 2 (CLN2 disease): an open-label extension study

BACKGROUND

Cerliponase alfa is a recombinant human tripeptidyl peptidase 1 (TPP1) enzyme replacement therapy for the treatment of neuronal ceroid lipofuscinosis type 2 (CLN2 disease), which is caused by mutations in the TPP1 gene. We aimed to determine the long-term safety and efficacy of intracerebroventricular cerliponase alfa in children with CLN2 disease.

METHODS

This analysis includes cumulative data from a primary 48-week, single-arm, open-label, multicentre, dose-escalation study (NCT01907087) and the 240-week open-label extension with 6-month safety follow-up, conducted at five hospitals in Germany, Italy, the UK, and the USA. Children aged 3-16 years with CLN2 disease confirmed by genetic analysis and enzyme testing were eligible for inclusion. Treatment was intracerebroventricular infusion of 300 mg cerliponase alfa every 2 weeks. Historical controls with untreated CLN2 disease in the DEM-CHILD database were used as a comparator group. The primary efficacy outcome was time to an unreversed 2-point decline or score of 0 in the combined motor and language domains of the CLN2 Clinical Rating Scale. This extension study is registered with ClinicalTrials.gov, NCT02485899, and is complete.

FINDINGS

Between Sept 13, 2013, and Dec 22, 2014, 24 participants were enrolled in the primary study (15 female and 9 male). Of those, 23 participants were enrolled in the extension study, conducted between Feb 2, 2015, and Dec 10, 2020, and received 300 mg cerliponase alfa for a mean of 272·1 (range 162·1-300·1) weeks. 17 participants completed the extension and six discontinued prematurely. Treated patients were significantly less likely than historical untreated controls to have an unreversed 2-point decline or score of 0 in the combined motor and language domains (hazard ratio 0·14, 95% CI 0·06 to 0·33; p<0·0001). All participants experienced at least one adverse event and 21 (88%) experienced a serious adverse event; nine participants experienced intracerebroventricular device-related infections, with nine events in six participants resulting in device replacement. There were no study discontinuations because of an adverse event and no deaths.

INTERPRETATION

Cerliponase alfa over a mean treatment period of more than 5 years was seen to confer a clinically meaningful slowing of decline of motor and language function in children with CLN2 disease. Although our study does not have a contemporaneous control group, the results provide crucial insights into the effects of long-term treatment.

FUNDING

BioMarin Pharmaceutical.

Ongoing retinal degeneration despite intraventricular enzyme replacement therapy with cerliponase alfa in late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2 disease)

BACKGROUND/AIMS

Late-infantile neuronal ceroid lipofuscinosis type 2 (CLN2) is a neurodegenerative, blinding lysosomal storage disorder. The purpose of the current study was to characterise the progression of CLN2-associated retinal degeneration in patients under intraventricular enzyme replacement therapy (ERT) with cerliponase alfa.

METHODS

We analysed visual function, retinal morphology and neuropaediatric data using preferential looking test (PLT), Weill Cornell Batten Scale (WCBS), optical coherence tomography (OCT) imaging and the Hamburg Motor-Language late-infantile neuronal ceroid lipofuscinosis (LINCL) Scale (M-L scale).

RESULTS

Fifty-six eyes of 28 patients had baseline PLT, WCBS and OCT. 15 patients underwent serial examinations, resulting in a total of 132 OCT scans and WCBS results, 66 Hamburg M-L scores and 49 PLT results during a mean follow-up time of 18.2 months (range 5-40). A negative correlation (r=-0.69, p<0.001) was found between central retinal thickness (CRT) values and age at examination with a maximal annual decrease of 23 µm between 56 and 80 months of age. A significant correlation was observed between PLT results and the age at examination (r=0.46, p=0.001), the WCBS scores (r=0.62; p<0.001) and CRT values (r=-0.64; p<0.001). The M-L score correlated with the ocular measurements (CRT: r=0.58, p<0.001; WCBS r=-0.64, p<0.001; PLT score: r=-0.57, p<0.001).

CONCLUSION

Despite intraventricular ERT, retinal degeneration progressed in patients with CLN2 and was particularly pronounced between 56 and 80 months of age. Retina-directed therapies should therefore be initiated before or as early as possible during the phase of rapid retinal degeneration. PLT and WCBS were identified as valuable outcome measures to monitor disease progression.

TRIAL REGISTRATION NUMBER

NCT04613089.

Visual perception and macular integrity in non-classical CLN2 disease

PURPOSE

Patients with CLN2 suffer from epileptic seizures, rapid psychomotor decline and vision loss in early childhood. The aim of the study was to provide longitudinal ophthalmic data of patients with confirmed genetic mutation and non-classical disease course, marked by later onset, protracted progression and prolonged life span.

METHODS

Prospective, observational study to assess visual acuity, retinal features (Weil Cornell Ophthalmic Score), central retinal thickness (CRT) measured by optical coherence tomography and general disease progression (Hamburg CLN2 motor language score) in non-classical CLN2 patients.

RESULTS

All patients received intracerebroventricular enzyme replacement therapy with cerliponase alfa. Mean age at last follow-up was 12.4 years; mean follow-up time 2.6 years. All cases demonstrated a stable Hamburg motor language CLN2 Score and Weill Cornell LINCL Ophthalmic Severity Score. Visual function remained stable in 4/6 patients, 2/6 patients showed a decrease, 4/6 cases had a stable CRT and 2/6 showed a reduction of CRT. One patient showed a massive macular thinning and low vision. A correlation with a specific mutation or age could not be verified.

DISCUSSION

The presented longitudinal study characterizes the variable ocular involvement in non-classical CLN2 disease and contributes to the natural history description. The functional and morphologic data outline the necessity of regular ophthalmic examination. Ocular phenotyping and description of retinal degeneration in non-classical CLN2 disease.

The Unified Batten Disease Rating Scale (UBDRS): Validation and reliability in an independent CLN3 disease sample

BACKGROUND

The neuronal ceroid lipofuscinoses (NCLs) are a group of disorders characterized by neurodegeneration and intracellular accumulation of an auto-fluorescent lipopigment. Together, NCLs represent the most common cause of cerebral neurodegenerative disease in children. CLN3 disease, the classic juvenile-onset form (JNCL) due to mutations in CLN3, is characterized by progressive vision loss, epilepsy, dementia, behavioral difficulties, and motor impairment. The Unified Batten Disease Rating Scale (UBDRS) is a disease-specific rating scale that was developed to assess disease severity in 4 domains: physical, behavior, seizures, and functional capability. Validity and reliability of the UBDRS has been established in a large North American cohort of over 130 individuals. The purpose of this study was to determine whether the UBDRS is valid and reliable when tested in an independent sample.

METHODS

Over the course of one week, 13 individuals with genetically confirmed CLN3 disease were evaluated with the UBDRS by 5 examiners at the University Medical Center Hamburg Eppendorf (UKE). One rater (JWM), one of the developers of the UBDRS, served as the reference standard. The other 4 raters were physicians with expertise in various forms of Batten Disease. After a formal training session, 13 individuals (age 16.5 ± 5.6 yrs) were evaluated simultaneous in parallel by the 5 raters. Inter-rater reliability of the Physical subscale was assessed with Intra-class Correlation (ICC) analysis. The relationship between age and severity was assessed and compared to previously published data from the North American cohort.

FINDINGS

The ICC among the 5 independent raters was 0.92, demonstrating excellent inter-rater reliability. The individual correlations of each UKE rater compared to the reference standard rater were all >0.95. The average UBDRS Physical Subscale score in this sample was 28 ± 21 (mean ± SD) with a range from 1 to 61. When evaluated as a function of participant age, the slope was 3.06 points/year (R² = 0.66).

INTERPRETATION

We have shown excellent interrater reliability for the UBDRS as a clinical rating scale for CLN3 disease in a sample independent from previous work. The results of this study are comparable to those published by Kwon et al., 2011 in a North American cohort showing a slope of 2.86 points per year with a 95% CI of 2.27-3.45 (N = 82). Our results demonstrate excellence inter-rater reliability after training a new group of raters and provide additional evidence for construct validity of the UBDRS. The UBDRS is a valid and reliable rating scale that can used by trained raters to assess the severity and rate of progression of CLN3 disease.

Development of the "Hamburg Best Practice Guidelines for ICV-Enzyme Replacement therapy (ERT) in CLN2 Disease" Based on 6 Years Treatment Experience in 48 Patients

Intracerebroventricular enzyme replacement therapy (ICV-ERT) for CLN2 disease represents the first approved treatment for neuronal ceroid lipofuscinosis (NCL) diseases. It is the first treatment where a recombinant lysosomal enzyme, cerliponase alfa, is administered into the lateral cerebral ventricles to reach the central nervous system, the organ affected in CLN2 disease. If untreated, CLN2 children show first symptoms such as epilepsy and language developmental delay at 2-4 years followed by rapid loss of motor and language function, vision loss, and early death. Treatment with cerliponase alfa has shown to slow the rapid neurologic decline. However, the mode of administration by 4 hour-long intracerebroventricular infusions every 14 days represents a potentially greater risk of infection compared to intravenous enzyme replacement therapies. The Hamburg NCL Specialty Clinic was the first site worldwide to perform intracerebroventricular enzyme replacement therapy in children with CLN2 disease. In order to ensure maximum patient safety, we analysed data from our center from more than 3000 intracerebroventricular enzyme replacement therapies in 48 patients over 6 years with regard to the occurrence of device-related adverse events and device infections. Since starting intracerebroventricular enzyme replacement therapy, we have also developed and continuously improved the "Hamburg Best Practice Guidelines for ICV-Enzyme Replacement Therapy (ERT) in CLN2 Disease." Results from this study showed low rates for device-related adverse events and infections with 0.27% and 0.33%, respectively. Therefore, following our internal procedural guidelines has shown to improve standardization and patient safety of intracerebroventricular enzyme replacement therapy for CLN2 disease.

Investigating health-related quality of life in rare diseases: a case study in utility value determination for patients with CLN2 disease (neuronal ceroid lipofuscinosis type 2)

Background

Utility studies enable preference-based quantification of a disease’s impact on patients’ health-related quality of life (HRQoL). It is often difficult to obtain utility values for rare, neurodegenerative conditions due to cognitive burden of direct elicitation methods, and the limited size of patient/caregiver populations. CLN2 disease (neuronal ceroid lipofuscinosis type 2) is an ultra-rare, progressive condition, for which there are no published utility data fully capturing all disease stages. This case study demonstrates how utility values can be estimated for ultra-rare paediatric diseases by asking clinicians to complete EQ-5D-5L questionnaires based on vignettes describing the stages of CLN2 disease.

Methods

An indirect elicitation method using proxy-reporting by clinical experts was adopted. Eighteen vignettes were developed, describing nine progressive disease stages as defined by motor and language domain scores of the CLN2 Clinical Rating Scale, in individuals treated with cerliponase alfa or standard care. Eight clinical experts with experience of treating CLN2 disease with cerliponase alfa and current standard care completed the proxy version 2 EQ-5D-5L online after reading these vignettes. Resulting scores were converted to EQ-5D-5L utility values for each disease stage, using UK, German and Spanish value sets.

Results

Utility values, which are typically anchored by 0 (equivalent to death) and 1 (full health), decreased with CLN2 disease progression (results spanned the maximum range of the utility scale). Assigned utility values were consistently higher for patients receiving cerliponase alfa than standard care; differences were statistically significant for the 6 most severe disease stages (p < 0.05). Analysis of the individual dimensions of the EQ-5D-5L showed that greatest differences between patients treated with cerliponase alfa and standard care occurred in the pain dimension (differences in mean scores ranged between no difference and 1.8), with notable differences also observed in the anxiety/depression dimension (differences in mean scores ranged between 0.1 and 1.0).

Conclusions

This study demonstrates a feasible methodology for eliciting utility values in CLN2 disease, indicating HRQoL declines with disease progression. Vignettes describing patients receiving cerliponase alfa were consistently assigned higher utility values for the same disease state, suggesting this treatment improves HRQoL compared with standard care.

Trial registration NCT01907087, NCT02485899.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01829-x.

Cerliponase Alfa for the Treatment of Atypical Phenotypes of CLN2 Disease: A Retrospective Case Series

BACKGROUND

The classic phenotype of CLN2 disease (neuronal ceroid lipofuscinosis type 2) typically manifests between ages 2 and 4 years with a predictable clinical course marked by epilepsy, language developmental delay, and rapid psychomotor decline. Atypical phenotypes exhibit variable time of onset, symptomatology, and/or progression. Intracerebroventricular-administered cerliponase alfa (rhTPP1 enzyme) has been shown to stabilize motor and language function loss in patients with classic CLN2 disease, but its impact on individuals with atypical phenotypes has not been described.

METHODS

A chart review was conducted of 14 patients (8 male, 6 female) with atypical CLN2 phenotypes who received cerliponase alfa. Pre- and posttreatment CLN2 Clinical Rating Scale Motor and Language (ML) domain scores were compared.

RESULTS

Median age at first presenting symptom was 5.9 years. First reported symptoms were language abnormalities (6 [43%] patients), seizures (4 [29%]), ataxia/language abnormalities (3 [21%]), and ataxia alone (1 [7%]). Median age at diagnosis was 10.8 years. ML score declined before treatment in 13 (93%) patients. Median age at treatment initiation was 11.7 years; treatment duration ranged from 11 to 58 months. From treatment start, ML score remained stable in 11 patients (treatment duration 11-43 months), improved 1 point in 1 patient after 13 months, and declined 1 point in 2 patients after 15 and 58 months, respectively. There were 13 device-related infections in 8 patients (57%) and 10 hypersensitivity reactions in 6 (43%).

CONCLUSIONS

Cerliponase alfa is well tolerated and has the potential to stabilize motor and language function in patients with atypical phenotypes of CLN2 disease.

Long Term Follow-Up on Pediatric Cases With Congenital Myasthenic Syndromes-A Retrospective Single Centre Cohort Study

Introduction: Congenital myasthenic syndromes (CMS) refer to a heterogenic group of neuromuscular transmission disorders. CMS-subtypes are diverse regarding exercise intolerance and muscular weakness, varying from mild symptoms to life-limiting forms with neonatal onset. Long-term follow-up studies on disease progression and treatment-response in pediatric patients are rare. Patients and Methods: We analyzed retrospective clinical and medication data in a cohort of 32 CMS-patients including the application of a standardized, not yet validated test (CMS-ST) to examine muscular strength and endurance in 21 patients at the last follow-up. Findings obtained in our cohort were compared with long-term follow-up studies of (adult) CMS-cohorts from the literature by considering the underlying molecular mechanisms. Outcomes of CMS-ST were compared to results of normal clinical assessment. Results: Thirty-two pediatric patients with defects in eight different CMS-genes were followed by a median time of 12.8 years. Fifty-nine percentage of patients manifested with first symptoms as neonates, 35% as infants. While 53% of patients presented a reduced walking distance, 34% were wheelchair-bound. Even under adequate therapy with pyridostigmine (PS) and 3,4-diaminopyridine, CHAT-mutations led to the progression of muscular weakness partly in combination with persistent respiratory and bulbar symptoms. RAPSN, CHRND, and CHRNB1 patients with neonatal manifestation, early respiratory problems, and bulbar symptoms showed a good and maintained treatment response. CHAT and CHRNE patients required higher PS dosages, whereas RAPSN patients needed a lower mean dosage at the last follow-up. The benefits of short-term medication and long-term progression of symptoms were highly dependent on the specific genetic defect. CMS-ST was carried out in 17/21 patients, determined affected muscle groups including bulbar and ocular symptoms, some of which were not reported by the patients. Conclusions: Our findings and comparison with the literature- suggest a better treatment-response and less severe progression of symptoms present in patients suffering from mutations in CMS-genes directly associated with receptor deficiency, while patients with defects leading to synaptopathy and presynaptic defects tend to have worse outcomes. Assessment of affected muscular groups and clinical symptoms by CMS-ST may be a useful tool for optimal therapeutic management of the patients, especially for future clinical studies.

An Ophthalmic Rating Scale to Assess Ocular Involvement in Juvenile CLN3 Disease

PURPOSE

Juvenile CLN3 disease, the most prevalent form of Batten disease, is a progressive neurodegenerative disorder resulting from mutations in the CLN3 gene. The objective of this study was to design an ophthalmic rating scale for CLN3 disease in order to quantify disease progression.

DESIGN

Retrospective, cross-sectional study.

METHODS

Patients underwent ophthalmic evaluations including visual testing, optical coherence tomography and fundus imaging. Patients were also assessed using the Hamburg Juvenile Neuronal Ceroid Lipofuscinosis (JNCL) scoring system. Ophthalmic findings were divided into grades of severity ranging from 0 to 3, and the association between the extent of ocular disease and neurological function and age was assessed.

RESULTS

Forty-two eyes of 21 patients were included. The mean age at the time of examination was 13.2 years (range, 5.3-21.9 years). The mean ophthalmic severity grade was 2.4 (range, 0-3). The mean neurological severity score was 9.9 (range, 4-14). Ophthalmic manifestations increased in severity with increasing age of the patients (r = -0.84; P < .001), and a strong correlation was found between the CLN3 ophthalmic rating scale score and the Hamburg JNCL score (r = 0.83; P < .001).

CONCLUSIONS

Ophthalmic manifestations of CLN3 disease correlate closely with the severity of neurological symptoms and age of the patient. The newly established Hamburg CLN3 ophthalmic rating scale may serve as an objective marker of ocular disease severity and progression and may be valuable tool for the evaluation of novel therapeutic strategies for CLN3 disease.