The Effect of Amantadine As Add-on Therapy for Motor Fluctuations in Advanced Parkinson's Disease: a Randomized Double-blinded Placebo-controlled Trial (AMANT-OFF)

Motor fluctuations are identified as the most challenging symptoms by parkinson disease patients. A recent post-hoc analysis of ADS-5012 trials (new formulation of ER Amantadine), revealed a significant improvement in OFF-time. No randomized clinical trial has ever specifically investigated to date the effect of amantadine IR on motor fluctuations. The main objective of this study is to evaluate the effect of amantadine (300 mg/day) as add-on therapy for the treatment of motor fluctuations (Off-time) in advanced Parkinson's disease patients versus placebo after 3 months of treatment.

Study Overview

• Status: Not yet recruiting
• Conditions: Parkinson Disease (PD)
• Intervention / Treatment: Drug: Amantadine (100mg) as add on therapy.; Drug: Placebo

Detailed Description

Parkinson's disease (PD) is the second most common age-related neurodegenerative disorder. Up to 50% of parkinson disease patients develop mild motor fluctuations (OFF-time) within 2 years of initiating levodopa therapy, increasing up to 70% of patients after 9 years. Motor fluctuations are identified as the most challenging symptoms by parkinson disease patients and considered as a key clinical unmet need for advanced parkinson disease patients. Amantadine has been approved by the FDA in 1973 for the "treatment of parkinson disease". It has a unique pharmacodynamic profile with both a dopaminergic and an anti-glutamatergic effect, which are related to its anti-parkinsonian and anti-dyskinetic action. In 2017, the FDA approved 2 new Amantadine extended release (ER) formulations for dyskinesia treatment, ADS-5012 and OS-320. In 2021 post-hoc analysis of ADS-5012 trials, revealed a significant improvement in OFF-time (1 h of reduction vs. placebo). These findings led to the FDA granting amantadine ER an additional indication as add-on treatment to levodopa for the management of motor fluctuations. No randomized clinical trial has ever specifically investigated to date the effect of amantadine Immediate Release on motor fluctuations. We hypothesize that the double action of amantadine could allow this drug to be effective in the treatment of motor fluctuations, without increasing dyskinesia. Parkinson disease patient with motor fluctuations will be included and followed up in this study. After 3 to 4 weeks of titration, patients will receive stable dose of amantadine (up to 300 mg/day) or matching placebo during 12 weeks.

• Study Type: Interventional
• Enrollment (Estimated): 132
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Margherita FABBRI, MD; Phone Number: +33 0561776039; Email: fabbri.m@chu-toulouse.fr

Study Locations

• France
  • Toulouse, France
    • CHU Toulouse
    • Contact: Margherita FABBRI, MD; Phone Number: +33 0561776039; Email: fabbri.m@chu-toulouse.fr
    • Contact: Margherita FABBRI, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

Parkinson's disease diagnosis in agreement with the MDS criteria (Postuma et al., 2015) for at least 3 years HY 2-3 in Med ON condition Age: 30-80 years Signs of motor fluctuations for at least 4 weeks before screening, with a mean total awake time in the off state of at least 2 h, including morning akinesia despite anti-parkinsonian drug adjustment (best medical treatment)" Amantadine naïve (all other oral add-on treatments for motor fluctuations are allowed) Concomitant anti-Parkinson drug use should be stable for at least 4 weeks prior to screening Patients affiliated or beneficiary of a social security scheme. Patients who signed the written informed consent form. Patients in capacity to complete Hauser diaries

Exclusion Criteria:

Severe or unpredictable periods in the Off-state, or both; Clinically significant and unstable cardiovascular disease, psychiatric illness (including major depression, dementia, impulse control, disorders, and suicide ideation), or any other medical disorder that might have placed the patient at increased risk; Patient with behavioral disorder, ECMP item ≥ 3 Patients previously submitted to advanced treatments: subcutaneous continuous apomorphine infusion, deep brain stimulation and levodopa-carbidopa intestinal gel; Patients with cognitive impairment (Mini Mental Status Examination < 26) Patients with a diagnosis of atypical parkinsonism (Progressive supranuclear Palsy, Multiple system atrophy, Lewy Body Dementia or Cortico-basal degeneration) Patients having any contraindication to amantadine treatment (see Summary of Product characteristic in the Appendix: known hypersensitivity to drugs of the amantadine class or any of the components, combination with anti-emetic neuroleptics, patient with a history of epilepsy, confusional state, hallucinations or severe psychoneurotic state not controlled by treatment, patient with a history of congestive heart failure or peripheral oedema, patient with a history of skin eczema) A history of neuroleptic malignant syndrome or nontraumatic Rhabdomyolysis; renal failure and renal insufficiency (creatinine > 150 µmol/L) states of agitation or confusion delirious syndromes or exogenous psychosis in the anamnesis Has received any other investigational drug within 30 days or 5 half-lives (whichever is longer) prior to screening or plans to use an investigational drug (other than the study intervention) during the study Pregnant female subjects or potential childbearing female participant without highly effective contraception

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Amantadine; Amantadine will be administered at the dose of 100 mg t.i.d or b.i.d. (if t.i.d. is not tolerated) over 12 weeks, after a period of 3 weeks of titration. The study treatment will be stopped after a dose decrease of 100 mg / day every 3 days.	Drug: Amantadine (100mg) as add on therapy.; Amantadine will be administered at the dose of 100 mg t.i.d or b.i.d. (if t.i.d. is not tolerated) over 12 weeks, after a period of 3 weeks of titration.T he study treatment will be stopped after a dose decrease of 100 mg / day every 3 days.
Placebo Comparator: Placebo; Placebo tablets will be also administered b.i.d. or t.i.d over 12 weeks after a period of 3 weeks of titration. Placebo tablets will be indistinguishable from amantadine ones.	Drug: Placebo; Placebo tablets will be also administered b.i.d. or t.i.d over 12 weeks after a period of 3 weeks of titration. Placebo tablets will be indistinguishable from amantadine ones.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
the change in motor fluctuation (Off-time)	The primary outcome of this study is the change from baseline to end-point (3 months) in motor fluctuation (Off-time) as assessed by the Hauser diaries (average of 3 consecutive days).	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The rate of Off-time responders	The change from baseline to end-point (3 months) of the rate of Off-time responders	3 months
The change of the mean score of MDS-UPDRS part IV	The change from baseline to end-point (3 months) of The mean score of Movement disorders society - Unified Parkinson's disease rating scale (MDS-UPDRS part IV)	3 months
The change of the mean score of UDysRS part 2A	The change from baseline to end-point (3 months) of the mean score of UDysRS part 2A	3 months
The change of the mean score of New freezing of gait questionnaire	The change from baseline to end-point (3 months) of the mean score of New freezing of gait questionnaire	3 months
The change of the mean score of Fatigue Severity Scale	The change from baseline to end-point (3 months) of the mean score of Fatigue Severity Scale	3 months
The change of the mean score of MDS-UPDRS Part I-II-III	The change from baseline to end-point (3 months) of the mean score of Movement disorders society - Unified Parkinson's disease rating scale (MDS-UPDRS Part I-II-III)	3 months
The change of the mean score of PDQ-39	The change from baseline to end-point (3 months) of the mean score of Parkinson's Disease Questionnaire (PDQ-39)	3 months
The safety of amantadine	The safety of amantadine, expressed as: the percentage of Adverse Events, of severe Adverse Events, of serious Adverse Events and of patients' discontinuation due to Adverse Events, all over the three months of treatment.	3 months

Collaborators and Investigators

• Sponsor: University Hospital, Toulouse

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2025
• Primary Completion (Estimated): May 1, 2025
• Study Completion (Estimated): August 31, 2027

Study Registration Dates

• First Submitted: February 4, 2025
• First Submitted That Met QC Criteria: February 4, 2025
• First Posted (Actual): March 25, 2025

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: February 4, 2025
• Last Verified: February 1, 2025

More Information

Terms related to this study

• Keywords: clinical trial; Parkinson's disease; Amantadine; Motor fluctuations
• Additional Relevant MeSH Terms: Synucleinopathies; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurodegenerative Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Parkinson Disease; Anti-Infective Agents; Physiological Effects of Drugs; Molecular Mechanisms of Pharmacological Action; Peripheral Nervous System Agents; Sensory System Agents; Antiviral Agents; Analgesics, Non-Narcotic; Analgesics; Neurotransmitter Agents; Dopamine Agents; Antiparkinson Agents; Anti-Dyskinesia Agents; Amantadine
• Other Study ID Numbers: RC31/23/0372; 2023-509728-16-00 (Ctis)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No