Nabilone Versus Amitriptyline in Improving Quality of Sleep in Patients With Fibromyalgia

Condition(s) targeted: Fibromyalgia; Sleep Initiation and Maintenance Disorders

Intervention: Amitriptyline Hydrochloride (Drug); Nabilone (Drug)

Phase: N/A

Status: Completed

Sponsored by: McGill University Health Center

Official(s) and/or principal investigator(s):
Mark A Ware, Principal Investigator, Affiliation: McGill University Health Centre, Pain Centre

Most chronic pain patients with insomnia are currently not well-managed using existing medications. If found to safely improve sleep with chronic pain patients, nabilone could be added to the treatment options available in the management of fibromyalgia and associated symptoms.

The principle hypothesis of this study is that nabilone at a dose of 0. 5-1mg is as efficacious as amitriptyline at a dose of 10-20mg, in improving sleep quality in patients with fibromyalgia.

Official title: Nabilone Versus Amitriptyline in Improving Quality of Sleep in Patients With Fibromyalgia

Study design: Treatment, Randomized, Double-Blind, Active Control, Crossover Assignment, Efficacy Study

Primary outcome: Quality of sleep assessed using the Leeds Sleep Evaluation Questionnaire and the Insomnia Severity Index

Secondary outcome:

Pain Intensity using the VAS (visual analogue scale)

Pain Quality using the McGill Pain Questionnaire

Mood using the Profile of Mood States (POMS) Questionnaire

Quality of Life using the Fibromyalgia Impact Questionnaire (FIQ)

Minimum age: 18 Years. Maximum age: N/A. Gender(s): Both.

Criteria:

Inclusion Criteria:

- Patients aged ≥18 years;

- A diagnosis of fibromyalgia according to the American College of Rheumatology

classification criteria (Wolfe F, Smythe HA, et al 1990);

- Suffering from self-reported disturbed sleep;

- Negative urine screen for cannabinoids;

- Women of childbearing potential must agree to use adequate contraception during study

and for 3 months after study;

- Ability to attend research centre every second week for approximately seven to nine

weeks and be able to be contacted by telephone during the study period;

- Stable drug regimen for 1 month prior to randomization;

- Normal liver (AST <3x normal) and renal function (serum creatinine <133µmol/L);

- Haematocrit >38%;

- Negative serum bHCG;

- Proficient in English or French;

- Willing and able to give written informed consent;

- Ability to follow study protocol (cognitive and situational).

Exclusion Criteria:

- Patients currently using cannabis or cannabinoid or tricyclic antidepressants (TCA)

and who are unable to undergo a 2 week washout period before entering the study;

- Pain due to cancer;

- Unstable cardiac disease such as cardiac arrhythmias, cardiac failure, ischaemic heart

disease and/or hypertension on clinical history and examination;

- History of psychotic disorder or schizophrenia;

- Known hypersensitivity to cannabinoids, amitriptyline, or related tricyclic

antidepressants;

- Currently taking or unable to stop taking monoamine oxidase inhibitors (a two-week

washout period is necessary for subjects taking MAOIs);

- History of seizures/epilepsy;

- Diagnosis of glaucoma;

- Urinary retention;

- Pregnancy and/or breast-feeding;

- Participation in other clinical trial in the 30 days prior to randomization;

- A recent manic episode (within the past year);

- Current suicidal ideation or history of suicide attempts

McGill University Health Centre, Pain Centre, Montreal, Quebec H3G 1A4, Canada

Starting date: April 2006
Ending date: March 2007
Last updated: May 16, 2007