A Phase 3 interventional study of PLX-200 and Placebo in Juvenile Neuronal Ceroid Lipofuscinosis, sponsored by Polaryx Therapeutics, Inc.. Withdrawn. Open to participants aged 6 Years to 18 Years. Per ClinicalTrials.gov, last updated 2026-08-19.
Sponsored by Polaryx Therapeutics, Inc. · Phase 3, Interventional, and Treatment
The purpose of this study is to evaluate the safety and efficacy of multiple doses of PLX-200 in patients with CLN3 disease.
This is a phase 3, double-blind, placebo-controlled, dose-titration study to evaluate escalating weight-based dose levels of PLX-200, provided as a solution that contains 15 mg/mL PLX-200 and administered orally using a syringe, as needed, twice daily (BID), 30 minutes before breakfast and dinner. Participants will enter the Titration Period, during which the starting dose of PLX-200 or placebo will be based on patient weight. Each patient's dose will be titrated upward on a weekly basis during the Titration Period, until he or she reaches a maximally tolerated dose (MTD) or the Week 5 dose for their weight category. The patient will then enter the Maintenance Period at the final Titration Period dose for a maximum of 60 weeks. Safety, efficacy, and pharmacokinetics will be assessed periodically. Thereafter, all patients will have the opportunity to receive active treatment in an Open-Label Extension (OLE) for an additional 36 weeks.
46 studies on the registry are indexed under Neuronal Ceroid-Lipofuscinoses; 12 are open to participants now.
Browse Neuronal Ceroid-Lipofuscinoses studies →Polaryx Therapeutics, Inc. is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
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This is randomized, placebo-controlled comparator study of PLX-200 in patients with CLN3 disease.
Drug: PLX-200
This is randomized comparator study of PLX-200 vs. placebo in a 2:1 ratio in patients with CLN3 disease.
Drug: Placebo
15 mg/mL oral solution of experimental drug
Also known as: Gemfibrozil
Taste and color-matched drug-free solution
Efficacy of PLX-200 in CLN3 as assessed by the change in the motor score of the Hamburg Rating Scale compared with that of the Placebo group
The change from baseline in the motor score of the Hamburg Rating Scale at Week 60 of maintenance therapy in participants treated with PLX-200 compared with that of Placebo group. Baseline is defined as the motor score of the Hamburg Rating Scale assessment prior to starting drug or Placebo group in the Titration Period. The Hamburg Rating Scale records a rating of 0 - 3 in four domains: motor skills, vision, language, and seizures, all from 0 - 3 which is worse to normal, respectively, with a minimum (worse) score of 0 to a maximum (normal) score of 12.
Time frame: 60 weeks
Number of patients with treatment-related adverse events, as assessed by CTCAE v5.0, abnormal laboratory results, and abnormal cardiovascular and/or abdominal findings.
The aggregate of clinical chemistries, hematology, urinalysis, electrocardiogram readings, abdominal ultrasound findings, and tabulation of the number and severity of adverse events will be compared with baseline values throughout the study to evaluate the safety and tolerability of PLX-200 at escalating oral doses in children with CLN3 disease.
Time frame: 96 weeks
Efficacy of PLX in each of the domains of the Hamburg Scale
Changes in the Baseline score of each of the 4 domains of the Hamburg Rating Scale (motor, language, visual, and seizures) at 24, 48, 60 (except motor score), 72, and 96 weeks of maintenance therapy in those treated with PLX-200 compared with those treated with Placebo. The Hamburg rating per domain is 0 - 3 with 3 representing worse outcomes.
Time frame: 24, 48, 60, 72 and 96 weeks
Assessment of the overall decline status in subjects treated with PLX-200 compared with the placebo group
The overall decline status (Yes/No) at Maintenance Weeks 60 and 96 in subjects treated with PLX-200 compared to those treated with Placebo. A subject will be considered to have an overall decline if either (i) a decrease from baseline in any of the 4 domains (motor, language, visual, seizure) of the Hamburg rating scale is observed or (ii) the assessment is missing at the visit for any reason. The Hamburg rating per domain is 0 - 3 with 3 representing worse outcomes.
Time frame: 60 and 96 weeks
Evaluation of the baseline motor score decline between PLX-200 and placebo
The Motor Score decline status (Yes/No) at Maintenance Weeks 60 and 96 in subjects treated with PLX-200 compared to those treated with Placebo using two alternative definitions. In Definition 1, a subject will be considered to have declined (i.e. worsened) if at least a one-point decrease from baseline in the motor score of the Hamburg scale is observed or if the visit is missing for any reason. In Definition 2, subjects with at least a 2-point decrease or if the visit is missing will be considered to have declined.
Time frame: 60 and 96 weeks
Assessment of changes in the baseline Clinical Impression of symptom severity between PLX-200 and Placebo groups
Changes from baseline in the Clinical Global Impression of symptom severity to 24, 48, 60, 72, and 96 weeks of maintenance therapy in those treated with PLX-200 compared with those treated with Placebo. The CGI severity scale (CGI-S) rates illness severity and the CGI-Improvement (CGI-I) which both rate on a scale of 1 - 7 which relates to improved/very much improved to worse disease.
Time frame: 24, 48, 60, 72, and 96 weeks
Assessment of changes in the baseline Pediatric Balance Scale between PLX-200 and Placebo groups
Change in the Pediatric Balance Scale (modified Berg Balance Scale) score from Baseline to 24, 48, 60, 72, and 96 weeks of maintenance therapy in those treated with PLX-200 compared with those treated with Placebo. The scale is age, weight, height, and gender specific but across all groups, the higher score between 0 - 4 represents better outcomes than 0 which is worse outcome.
Time frame: 24, 48, 60, 72, and 96 weeks
Assessment of changes in the baseline Montreal Assessment Cognitive Scale between PLX-200 and Placebo groups
Change in the Montreal Cognitive Assessment (MoCA) score from Baseline to 24, 48, 60, 72, and 96 weeks of maintenance therapy in those treated with PLX-200 compared with those treated with Placebo. The MoCA cutoff score of 26 differentiates youth with and without cognitive impairment with the lower score being considered increased cognitive impairment.
Time frame: 24, 48, 60, 72, and 96 weeks
Assessment of changes in the baseline Vineland Behavior Scale between PLX-200 and Placebo groups
Change in the Vineland Behavior Scale from Baseline to 24, 48, 60, 72, and 96 weeks of maintenance therapy in those treated with PLX-200 compared with those treated with Placebo. The Vineland Scale captures changes in intellectual and developmental disabilities. To date, there are no normal values determined for the Vineland Behavior Scale but the higher the score suggests greater capabilities.
Time frame: 24, 48, 60, 72, and 96 weeks
Assessment of changes in the baseline walking ability of the patient between PLX-200 and Placebo groups
Change in walking ability (6-minute walk test; 6MWT) from Baseline to weeks 24, 48, 60, 72, and 96 weeks of maintenance therapy in those treated with PLX-200 compared with those treated with Placebo. The 6MWT normal range is highly specific to the patient. Thus, all tests will be compared to the Baseline value during the Screening Phase.
Time frame: 24, 48, 60, 72, and 96 weeks
PLX-200 pharmacokinetics (PK) will be evaluated through periodic blood draws during the trial. PLX-200 levels will be determined to estimate area under the curve, maximal concentration, time to maximal concentration, half-life, and dosing interval
To evaluate PLX-200 plasma concentrations in blood collected from participants during the Titration and Maintenance Periods for PK analyses, namely Cmax (maximal PLX-200 concentration) and Tmax (time to Cmax), elimination half-life (t1/2), area under the plasma concentration-time curve (AUC), and the dosing interval.
Time frame: 96 weeks
No study locations are listed for this record.
Plan to share: No — None planned.
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This study is withdrawn, as verified in Jul 2026. You cannot join it, but the record below documents what was studied.
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Neuronal Ceroid-Lipofuscinoses→
Polaryx Therapeutics, Inc.