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Clenbuterol on Motor Function in Individuals With Amyotrophic Lateral Sclerosis

A Clinical Investigation of the Safety and Efficacy of Clenbuterol on Motor Function in Individuals With Amyotrophic Lateral Sclerosis

Status
Completed
Phases
Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04245709
Enrollment
25
Registered
2020-01-29
Start date
2020-02-10
Completion date
2021-03-10
Last updated
2022-09-06

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

Conditions

Amyotrophic Lateral Sclerosis

Brief summary

The purpose of this study is to assess the safety and tolerability of clenbuterol (taken by mouth) in subjects with ALS (amyotrophic lateral sclerosis) and to assess the effectiveness of clenbuterol with regard to motor function in subjects with ALS. Subjects will be in this study approximately 24 weeks. The study drug, clenbuterol, is taken twice a day. As part of this study subjects will have the following tests and procedures: medical history, vital signs, physical examination, blood tests, heart and lung function tests, muscle function test, ALSFRS-R (ALS Functional Rating Scale Revised), thyroid function and for women who can become pregnant, pregnancy tests.

Detailed description

This is an open label pilot trial in which 25 people with ALS will take clenbuterol orally at 40-80 micrograms twice daily for 24 weeks. In person visits will occur at weeks 0, 4, 12 and 24. Telephone visits will occur at weeks 1, 6, 16 and 20. During these visits several safety and efficacy outcome measures will be performed for research purposes including safety labs, thyroid functions, pregnancy testing, ALSFRS-R, FVC (forced vital capacity), and muscle strength testing (myometry). The critical test of treatment efficacy will be the comparison of the ALSFRS-R slope during treatment to the estimated pre-treatment slope. All participants will continue to have standard follow up care for their ALS at Duke (for patients followed here) or their local ALS clinic

Interventions

The intervention is treatment with oral clenbuterol at 40-80 micrograms twice daily for 24 weeks. Dosage will initially be 40 mcg daily for one week, then 40 mcg BID per oral daily for the next 5 weeks. If the 40 mcg BID per oral is well tolerated in the opinion of Dr. Bedlack, the dose will be increased to 80 mcg each morning/40 mcg each evening for one week, followed by 80 mcg BID per oral for the remainder of the study. The selected target dose (80 mcg BID) is based upon the experience with the long-term administration of clenbuterol, specifically the beneficial muscle effects in a Phase I/II clinical trial that enrolled patients with late-onset Pompe disease who were previously treated with enzyme replacement therapy (Koeberl et al. 2018).

Sponsors

Dwight Koeberl, M.D., Ph.D.
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

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

Inclusion criteria

* Diagnosis of possible or more definite ALS according to the El Escorial criteria * FVC \>50% of predicted for age, height and gender. * At least four of 12 ALSFRS-R questions scored as 2 or 3 at screening. * Diminished but measurable grip strength (1) in at least one hand (females:10-50 pounds; males, 10-70 pounds). * Taking riluzole at a stable dose or not taking riluzole at screening. * On Radicava at a stable dose for at least 30d or not taking this * Life expectancy at least 6 months * Able to swallow tablets without crushing. * Age: 18+ years at enrollment. * Subjects are capable of giving written consent. * If sexually active, must agree to use contraceptive or abstinence for duration of treatment * Females of child bearing age must have negative pregnancy test at screening

Exclusion criteria

* Concurrent illness or laboratory abnormalities that could confound the measurement of ALS progression or interfere with the ability to complete the study. * Taking any investigational study drug within 30 days of screening or five half-lives of the prior agent. * No previous exposure to clenbuterol. * Pregnancy * Clinically relevant EKG abnormality (arrhythmia, cardiomyopathy) * Tachycardia (resting heart rate greater than 100 beats per minute) * History of seizure disorder * Hyperthyroidism * Pheochromocytoma * Pregnancy * Have any other co-morbid conditions that in the opinion of the study investigator, places the participant at increased risk of complications, interferes with study participation or compliance, or confounds study objectives * History of hypersensitivity to 2-agonist drugs such as albuterol, levalbuterol (Xopenex), bitolterol (Tornalate), pirbuterol (Maxair), terbutaline, salmeterol (Serevent). * The use of the following concomitant meds is prohibited during the study: diuretics (furosemide, Lasix), digoxin (digitalis, Lanoxin);blockers such as atenolol (Tenormin), metoprolol (Lopressor), and propranolol (Inderal); tricyclic antidepressants such as amitriptyline (Elavil, Etrafon), doxepin (Sinequan), imipramine (Janimine, Tofranil), and nortriptyline (Pamelor); monoamine oxidase inhibitors such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate); or other bronchodilators such as albuterol (Ventolin), levalbuterol (Xopenex), bitolterol (Tornalate), pirbuterol (Maxair), terbutaline (Brethine, Bricanyl), salmeterol (Serevent), isoetherine (Bronkometer), metaproterenol (Alupent, Metaprel), or isoproterenol (Isuprel Mistometer).

Design outcomes

Primary

MeasureTime frameDescription
Number of Participants With Serious Adverse Events as Measured by Patient ReportingUp to 24 weeksThe primary endpoint is safety of clenbuterol at 80 mcg BID. Adverse events and serious adverse events will be systematically gathered as the dose is increased.

Secondary

MeasureTime frameDescription
Change in Motor Function Measured by ALSFRS-RBaseline, week 4, week 12, week 16, week 20, and week 24The ALS Functional Rating Scale (ALSFRS-R) - 12 questions rated on a five-point scale, where 0= can't do, to 5= normal ability. It is utilized for monitoring the progression of disability in patients with ALS. The critical test for efficacy was comparison of the mean slope of the ALSFRS-R during treatment compared to pre-treatment. Pre-treatment slope for each participant was estimated as follows: (48-enrollment ALSFRS-R)/months since symptom onset. A statistically significant treatment effect was determined by a two-tailed, t-test, with a critical p value \< .05. Other analyses included a repeated measures ANOVA design (between and within subjects) of ALSFRS-R slopes before and during treatment.
FVC Decline, Per-protocol ComparisonBaseline, week 4, week 12, and week 24Comparison of the mean slope of percent predicted FVC during treatment versus pre-treatment. Pre-treatment slope for each participant was estimated as follows: (100%-enrollment percent predicted FVC)/months since symptom onset.

Countries

United States

Participant flow

Participants by arm

ArmCount
Open Label Arm
This is an open label pilot trial in which 25 people with ALS will take clenbuterol orally at 40-80 micrograms twice daily for 24 weeks. Clenbuterol: The intervention is treatment with oral clenbuterol at 40-80 micrograms twice daily for 24 weeks. Dosage will initially be 40 mcg daily for one week, then 40 mcg BID per oral daily for the next 5 weeks. If the 40 mcg BID per oral is well tolerated in the opinion of Dr. Bedlack, the dose will be increased to 80 mcg each morning/40 mcg each evening for one week, followed by 80 mcg BID per oral for the remainder of the study. The selected target dose (80 mcg BID) is based upon the experience with the long-term administration of clenbuterol, specifically the beneficial muscle effects in a Phase I/II clinical trial that enrolled patients with late-onset Pompe disease who were previously treated with ERT (Koeberl et al. 2018).
25
Total25

Withdrawals & dropouts

PeriodReasonFG000
Overall StudyAdverse Event13
Overall StudyRisk of travel during COVID19 pandemic1

Baseline characteristics

CharacteristicOpen Label Arm
Age, Categorical
<=18 years
0 Participants
Age, Categorical
>=65 years
7 Participants
Age, Categorical
Between 18 and 65 years
18 Participants
Age, Continuous59 years
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
22 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
3 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
Race (NIH/OMB)
Asian
0 Participants
Race (NIH/OMB)
Black or African American
0 Participants
Race (NIH/OMB)
More than one race
0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
Race (NIH/OMB)
Unknown or Not Reported
2 Participants
Race (NIH/OMB)
White
23 Participants
Region of Enrollment
United States
25 participants
Sex: Female, Male
Female
12 Participants
Sex: Female, Male
Male
13 Participants

Adverse events

Event typeEG000
affected / at risk
deaths
Total, all-cause mortality
0 / 25
other
Total, other adverse events
25 / 25
serious
Total, serious adverse events
2 / 25

Outcome results

Primary

Number of Participants With Serious Adverse Events as Measured by Patient Reporting

The primary endpoint is safety of clenbuterol at 80 mcg BID. Adverse events and serious adverse events will be systematically gathered as the dose is increased.

Time frame: Up to 24 weeks

Population: Intention to treat analyses were performed for 20 participants who had at least one ALSFRS-R measurement post-treatment.

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Open Label ArmNumber of Participants With Serious Adverse Events as Measured by Patient Reporting2 Participants
Secondary

Change in Motor Function Measured by ALSFRS-R

The ALS Functional Rating Scale (ALSFRS-R) - 12 questions rated on a five-point scale, where 0= can't do, to 5= normal ability. It is utilized for monitoring the progression of disability in patients with ALS. The critical test for efficacy was comparison of the mean slope of the ALSFRS-R during treatment compared to pre-treatment. Pre-treatment slope for each participant was estimated as follows: (48-enrollment ALSFRS-R)/months since symptom onset. A statistically significant treatment effect was determined by a two-tailed, t-test, with a critical p value \< .05. Other analyses included a repeated measures ANOVA design (between and within subjects) of ALSFRS-R slopes before and during treatment.

Time frame: Baseline, week 4, week 12, week 16, week 20, and week 24

Population: Intention to treat analyses were performed for 20 participants who had at least one ALSFRS-R measurement post-treatment. These calculations for ALSFRS-R were based on the 11 patients who completed all 6 months on some dose of the drug, e.g. the per-protocol group.

ArmMeasureValue (MEAN)Dispersion
Open Label ArmChange in Motor Function Measured by ALSFRS-R-0.17 slopeStandard Deviation 0.25
Secondary

FVC Decline, Per-protocol Comparison

Comparison of the mean slope of percent predicted FVC during treatment versus pre-treatment. Pre-treatment slope for each participant was estimated as follows: (100%-enrollment percent predicted FVC)/months since symptom onset.

Time frame: Baseline, week 4, week 12, and week 24

Population: For the 11 patients who completed all 6 months on some dose of the drug, there were 10 who had at least two FVC measurements. Seven patients had a baseline FVC measurement which was used to calculate the pre-treatment slope estimate, for the 3 patients without a baseline measurement, imputation of the baseline FVC was performed using all data available for each patient.

ArmMeasureValue (MEAN)Dispersion
Open Label ArmFVC Decline, Per-protocol Comparison-0.25 slopeStandard Deviation 0.85

Source: ClinicalTrials.gov · Data processed: Feb 9, 2026