Plain English Summary
Background and study aims
Pain is a major problem affecting one-third of Canadians and costing $850 billion/year in North America alone. Fibromyalgia (FM) is a common long-term condition, which causes widespread muscle and joint pain all over the body. The exact cause of FM is unknown, but it is thought that a variety of physical, mental and emotional factors are responsible. FM is also common in elderly patients emphasizing the urgent need to improve treatment as the population ages. Current pain-relieving medications (analgesics) used provide incomplete relief and disabling side effects such as tiredness and mental slowing – already prominent in people suffering from FM, and the elderly. Alpha-lipoic acid (ALA) is an antioxidant which has proven effective in the treatment of neuropathic pain (pain caused by nerve damage) with minimal side effects. ALA could potentially be an effective treatment for FM, as it does not make existing symptoms, such as tiredness and mental slowing, worse. The aim of this study is to test the effectiveness of ALA in treating pain in FM.
Who can participate?
Adults with fibromyalgia who have experienced at least moderate pain for at least three months.
What does the study involve?
Participants are randomly allocated to one of two groups who receive the two treatments in a different order. One treatment involves receiving the study medication (ALA) by mouth, three times a day for four weeks. The other treatment involves taking an identical looking placebo (dummy pill) by mouth, three times a day for four weeks. Each of the treatment periods will consist of three weeks of gradual dose increase, a week taking the maximal dose treatment (week four) and a ‘washout’ week when no study medication is taken at all (week five). Participants in both groups are interviewed by telephone every week in order to find out if the medication has had an effect on their pain intensity.
What are the possible benefits and risks of participating?
Participants may possibly benefit from pain reduction after taking the ALA. There is a small risk that participants may experience unwanted side effects from the ALA, including nausea and vomiting, headache and vertigo (spinning sensation when still).
Where is the study run from?
Providence Care, Kingston (Canada)
When is the study starting and how long is it expected to run for?
November 2015 to December 2018
Who is funding the study?
Physicians Services Incorporated Foundation (Canada)
Who is the main contact?
Dr Ian Gilron
Trial website
Additional identifiers
EudraCT number
ClinicalTrials.gov number
Protocol/serial number
ANAE-287-15
Study information
Scientific title
Double-blind, randomized, placebo-controlled trial of alpha-lipoic acid for fibromyalgia
Acronym
IMPALA
Study hypothesis
Alpha-lipoic acid is safe and superior to placebo in treating pain in fibromyalgia.
Ethics approval
The Queen's University Health Sciences and Affiliated Teaching Hospitals Research Ethics Board, 03/12/2015, ref: ROMEO/TRAQ #6016602
Study design
Single-center prospective interventional double-blind randomized placebo-controlled crossover trial
Primary study design
Interventional
Secondary study design
Randomised cross over trial
Trial setting
Hospitals
Trial type
Treatment
Patient information sheet
Not available in web format, please use the contact details to request a patient information sheet
Condition
Fibromyalgia
Intervention
Participants are randomly allocated to one of two groups by the research pharmacist using a computer-generated randomization code.
Group 1: Participants are treated with alpha-lipoic acid 600 mg orally three times daily for four weeks, followed by one week washout period. The participants then take an identical looking placebo three times daily for four weeks.
Group 2: Participants are treated with a placebo orally three times daily for four weeks, followed by one week washout period. The participants then take alpha-lipoic acid 600 mg three times daily for four weeks.
Participants in both groups are contacted weekly by telephone to measure pain intensity.
Intervention type
Drug
Phase
Phase II
Drug names
Alpha-lipoic acid
Primary outcome measure
Pain intensity is measured using mean daily “average” pain intensity at maximal tolerated dose, of each period is determined by averaging the daily pain intensity, as measured using the 0-10 Numerical Rating Scale over the 7 days of week 4 of each treatment period (alpha-lipoic acid and placebo).
Secondary outcome measures
1. Adverse effects are measured using ratings of frequency and severity of treatment-emergent adverse effects weekly throughout the study
2. Fibromyalgia pain impact is measured using the fibromyalgia Impact Questionnaire at 4 and 9 weeks
3. Sleep quality is measured using the Medical Outcomes Study Sleep Scale at 4 and 9 weeks
4. Global treatment response is measured using the Patient Global Impression of Change at 4 and 9 weeks
5. Fibromyalgia pain impact is measured using the Brief Pain Inventory at 4 and 9 weeks
6. Mood is measured using the Beck Depression Inventory-2 at 4 and 9 weeks
7. Anxiety is measured using the Beck Anxiety Inventory at 4 and 9 weeks
8. Pain quality descriptors are measured using the short form McGill Pain Questionnaire at 4 and 9 weeks
9. Quality of life is measured using the SF-36 survey at 4 and 9 weeks
10. Quality of treatment blinding is measured using a blinding questionnaire at 4 and 9 weeks
11. Acetaminophen consumption is measured using a daily diary at 4 and 9 weeks
Overall trial start date
01/11/2015
Overall trial end date
30/12/2018
Reason abandoned (if study stopped)
Eligibility
Participant inclusion criteria
1. Aged 18 and older
2. Meeting the 2010 American College of Rheumatology diagnostic criteria for fibromyalgia
3. Experienced at least moderate daily pain (Numerical Rating Scale ≥ 4/10) for at least 3 months prior to study entry
4. AST (aspartate aminotransferase)/ALT (alanine aminotransferase) no greater than 20% the upper limit of normal
5. Serum creatinine no greater than 50% the upper limit of normal
6. Necessary abilities, visual acuity and language skills for pain diary completion and telephone communication with study nurses
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
30
Participant exclusion criteria
1. Any major organ system disease
2. Major poorly controlled psychiatric disorder
3. Severe depression or suicidal ideation
4. Active substance abuse disorder
5. Lactose intolerance
6. Hypersensitivity to ALA
7. Painful condition more than 50% as severe as their fibromyalgia pain
8. Unwillingness to use a highly effective form of contraception (women of childbearing potential)
Recruitment start date
01/07/2016
Recruitment end date
30/04/2018
Locations
Countries of recruitment
Canada
Trial participating centre
Providence Care
St. Mary's of the Lake Hospital
340 Union Street
Kingston
K7L 5A2
Canada
Funders
Funder type
Research organisation
Funder name
Physicians' Services Incorporated Foundation
Alternative name(s)
PSI Foundation, PSI
Funding Body Type
private sector organisation
Funding Body Subtype
Trusts, charities, foundations (both publically funded and privately funded)
Location
Canada
Results and Publications
Publication and dissemination plan
1. Planned publication in an indexed, peer-reviewed, biomedical journal
2. Planed presentation at an international scientific meeting
Intention to publish date
28/02/2019
Participant level data
Available on request
Basic results (scientific)
Publication list
2017 results in: https://www.ncbi.nlm.nih.gov/pubmed/28351829