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A Clinical Trial of 2 Doses of PRAX-944 in Participants With Essential Tremor

A Phase 2, Randomized, Double-Blind, Placebo-Controlled, Dose Range Finding Clinical Trial to Evaluate the Efficacy, Tolerability, and Safety of PRAX-944 in the Treatment of Adults With Essential Tremor

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05021991
Acronym
Essential1
Enrollment
133
Registered
2021-08-26
Start date
2021-10-14
Completion date
2024-02-29
Last updated
2024-03-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Essential Tremor

Keywords

Movement Disorder, Benign Essential Tremor, Familial Tremor, Hereditary Essential Tremor, Movement Disorder Agents, Calcium Channels, T-type

Brief summary

This multi-center, randomized, double-blinded, placebo-controlled, dose-range-finding clinical trial (with an optional Extension comprised of an Extension Double-blind (DB) Lead in Period followed by an Extension Open-label (OL) Period) that will assess the efficacy, safety, and tolerability of PRAX 944 in participants aged 18 years or older who have a diagnosis of Essential Tremor (ET) and have had symptoms for at least 3 years.

Interventions

DRUG100 mg PRAX-944

Once daily oral treatment with titration

DRUG60 mg PRAX-944

Once daily oral treatment with titration

DRUGPlacebo

Once daily oral treatment

DRUGFlexibly dosed 20 mg to 100 mg PRAX-944

Once daily oral treatment

Sponsors

Praxis Precision Medicines
Lead SponsorINDUSTRY

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

1. Clinical diagnosis of ET, including: (a) tremor syndrome of bilateral upper limb action tremor, (b) at least 3 years in duration, (c) with or without tremor in other locations (eg, head, voice, or lower limbs), (d) If the symptoms and signs are judged by the investigator to be due to the diagnosis of ET, it is acceptable for them to also have one or more of the following ET plus signs: (i) mild dystonic posturing, (ii) mild rest tremor in the setting of advanced ET and in the absence of other features of Parkinsonism, (iii) intention tremor, (iv) mild increase in tandem gait difficulty. 2. Participant has moderate to severe functional impairment due to tremor as determined by the TETRAS and CGI-S. 3. If currently receiving any medication for ET, is on a stable dose of any of these medications for ET for 1 month prior to Screening and is willing to maintain stable doses throughout the trial. If receiving primidone for ET, is willing and able to discontinue 14 days prior to Day 1. 4. Body mass index (BMI) between 18 and 40 kg/m² (inclusive).

Exclusion criteria

1. Sporadically using a benzodiazepine, sleep medication, or anxiolytic that would confound the assessment of tremor. 2. Trauma to the nervous system within 3 months preceding the onset of tremor. 3. History or clinical evidence of other medical, neurological, or psychiatric condition that may explain or cause tremor, including but not limited to Parkinson's disease, Huntington's disease, Alzheimer's disease, cerebellar disease (including spinocerebellar ataxias), primary dystonia, Fragile X Tremor/Ataxia syndrome or family history of Fragile X syndrome, traumatic brain injury, psychogenic tremor, alcohol or benzodiazepine abuse or withdrawal, multiple sclerosis, polyneuropathy, and endocrine states such as hyperthyroidism or unstable treatment of hypothyroidism or medication, food, or supplement induced movement disorders (eg, tremor related to beta agonists or caffeine), or other medical, neurological, or psychiatric conditions that may explain or cause tremor 4. Prior magnetic resonance-guided focused ultrasound or surgical intervention for ET such as deep brain stimulation or thalamotomy. 5. Botulinum toxin injection for ET in the 6 months prior to Baseline. 6. Cala trio health device for ET in the 14 days prior to Baseline and throughout the study. 7. History of substance use disorder consistent with Diagnostic and Statistical Manual of Mental Disorders (DSM)-5 criteria. Participants with a previous diagnosis of substance use disorder who have been in remission for at least 2 years can participate in the trial.

Design outcomes

Primary

MeasureTime frameDescription
Change from baseline to Day 56 on the modified ADL56 daysThe modified ADL is a composite sum of items 1 to 11 of the TETRAS-ADL subscale and items 6 and 7 on the TETRAS-PS. The impact to each function is rated on a 5-point Likert scale from 0 to 4. Before calculating the total score, a scoring adjustment is applied to each item score. The modified ADL score is calculated as the sum of all 13 items (with scoring adjustments) and ranges from 0 to 42 where larger values represent increased direct tremor impact to activities of daily living.

Secondary

MeasureTime frameDescription
Clinical Global Impression-Improvement (CGI-I) score at Day 5656 daysThe CGI-I assesses the participant's improvement (or worsening). The clinician is required to assess the participant's condition relative to pre-treatment on a 7-point scale from 1 (very much improved) to 7 (very much worse). In all cases, the assessment should be made independent of whether the rater believes the improvement/worsening is drug-related or not.
Change from baseline to Day 56 on the TETRAS-ADL score56 daysThe TETRAS-ADL subscale is a 12-item assessment of typical daily activities that are impacted by tremor. Activities are assessed in the following functional domains: speaking, feeding, drinking, personal hygiene, dressing, writing, and social activity. The impact to each function is rated on a 5-point Likert scale from 0 to 4. The ADL subscale score is calculated as the sum of all 12 items and ranges from 0 to 48 where larger values represent increased direct tremor impact to activities of daily living.
Change from baseline to Day 56 on the TETRAS-Performance Subscale (PS) total score56 daysThere are 9 items covering different body regions in the Performance Subscale. Each Performance Subscale item is rated on a scale of 0 to 4, with higher scores indicating higher tremor severity. Item 4 of the Performance Subscale is the upper limb item. It is comprised of 6 sub-items (4a, 4b, and 4c assessed for both the right and left upper limbs). The Performance subscale score is calculated as the sum of all 9 items and ranges from 0 to 64 where larger values represent higher tremor severity.
Change from baseline to Day 56 on the TETRAS-upper limb (UL) score (TETRAS-PS item 4)56 daysItem 4 of the Performance subscale is the upper limb item. It is comprised of 6 sub-items (4a, 4b, and 4c assessed for both the right and left upper limbs). Each sub-item is rated on a scale from 0 to 4, with higher scores indicating higher tremor amplitude of the upper limb. The upper limb total score is the sum of these 6 sub-items and ranges from 0 to 24 where larger values represent higher tremor severity.
Change from baseline to Day 56 on the TETRAS-combined upper limb (CUL) score (TETRAS-PS sum of items 4, 6, 7, and 8)56 daysThe combined upper limb score is the sum of the 6 sub-item scores of the upper limb item and the handwriting and spirals scores. The combined upper limb score ranges from 0 to 32 where larger values represent higher tremor severity.
Patient Global Impression-Change (PGI-C) score at Day 5656 daysThe PGI-C assesses the participant's change in condition. The participant is required to assess their condition relative to Baseline (Pre-dose on Day 1) on a 7-point scale from 1 (very much improved) to 7 (very much worse). In all cases, the assessment should be made independent of whether the participant believes the change is drug-related or not.
Change from baseline to Days 14, 28, and 42 on the modified ADLUp to 42 daysThe modified ADL is a composite sum of items 1 to 11 of the TETRAS-ADL subscale and items 6 and 7 on the TETRAS-PS. The impact to each function is rated on a 5-point Likert scale from 0 to 4. Before calculating the total score, a scoring adjustment is applied to each item score. The modified ADL score is calculated as the sum of all 13 items (with scoring adjustments) and ranges from 0 to 42 where larger values represent increased direct tremor impact to activities of daily living.
Change from baseline to Day 56 on the Clinical Global Impression-Severity (CGI-S)56 daysThe CGI-S assesses the clinician's impression of the participant's current illness state. The clinician should use his/her total clinical experience with this patient population and rate the current severity of the participant's ET on a 7-point scale from 1 (normal, not at all ill) to 7 (among the most extremely ill patients).
Change from baseline to Days 14, 28, and 42 on the TETRAS-ADL total scoreUp to 42 daysThe TETRAS-ADL subscale is a 12-item assessment of typical daily activities that are impacted by tremor. Activities are assessed in the following functional domains: speaking, feeding, drinking, personal hygiene, dressing, writing, and social activity. The impact to each function is rated on a 5-point Likert scale from 0 to 4. The ADL subscale score is calculated as the sum of all 12 items and ranges from 0 to 48 where larger values represent increased direct tremor impact to activities of daily living.
Change from baseline to Days 14, 28, and 42 on the TETRAS-UL scoreUp to 42 daysItem 4 of the Performance subscale is the upper limb item. It is comprised of 6 sub-items (4a, 4b, and 4c assessed for both the right and left upper limbs). Each sub-item is rated on a scale from 0 to 4, with higher scores indicating higher tremor amplitude of the upper limb. The upper limb total score is the sum of these 6 sub-items and ranges from 0 to 24 where larger values represent higher tremor severity.
Change from baseline to Days 14, 28, and 42 on the TETRAS-CUL scoreUp to 42 daysThe combined upper limb score is the sum of the 6 sub-item scores of the upper limb item and the handwriting and spirals scores. The combined upper limb score ranges from 0 to 32 where larger values represent higher tremor severity.
CGI-I scores at Days 14, 28, and 42Up to 42 daysThe CGI-I assesses the participant's improvement (or worsening). The clinician is required to assess the participant's condition relative to pre-treatment on a 7-point scale from 1 (very much improved) to 7 (very much worse). In all cases, the assessment should be made independent of whether the rater believes the improvement/worsening is drug-related or not.
PGI-C scores at Days 14, 28, and 42Up to 42 daysThe PGI-C assesses the participant's improvement (or worsening). The participant is required to assess their condition relative to Baseline (Pre-dose on Day 1) on a 7-point scale from 1 (very much improved) to 7 (very much worse). In all cases, the assessment should be made independent of whether the participant believes the improvement/worsening is drug-related or not.
Change from baseline to Day 42 on the TETRAS-PS total score42 daysThere are 9 items covering different body regions in the Performance Subscale. Each Performance Subscale item is rated on a scale of 0 to 4, with higher scores indicating higher tremor severity. Item 4 of the Performance Subscale is the upper limb item. It is comprised of 6 sub-items (4a, 4b, and 4c assessed for both the right and left upper limbs). The Performance subscale score is calculated as the sum of all 9 items and ranges from 0 to 64.
Number of participants with Adverse Events (AE)Up to 56 daysThe number of participants with Adverse Events (AE) will be reported by preferred term.
Change from baseline to Days 14, 28, and 42 on the CGI-SUp to 42 daysThe CGI-S assesses the clinician's impression of the participant's current illness state. The clinician should use his/her total clinical experience with this patient population and rate the current severity of the participant's ET on a 7-point scale from 1 (normal, not at all ill) to 7 (among the most extremely ill patients).

Countries

Canada, United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026