Chronic Low Back Pain Research Project
Condition: Chronic Low Back Pain
MeSH terms: Back Pain; Low Back Pain
Intervention: gabapentin; Inert placebo
Intervention description: Gabapentin 300m on Day 1, with daily or weekly increase to 3600 mg (maximum) by mouth by Week 5 of the 12-week trial; Inactive placebo capsule, one capsule on Day 1 with daily or weekly increase to 9 capsules daily by Week 5 of the 12-week trial
Intervention MeSH terms: Gabapentin
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Enrollment: 108.0
Sex: All
Minimum age: 21 Years
Maximum age: 70 Years
Healthy volunteers: No
Keywords: analgesia; antidepressant agents; back pain; pain

Summary:

      The purpose of this study is to determine whether gabapentin is efficacious as an analgesic
      for chronic low back pain.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Must be resident of the county of San Diego, California

          -  Ages 21-70 inclusive

          -  Low back pain (T-6 or below, secondary to degenerative disk or degenerative joint
             disease) present "on a daily basis" for the previous 6 months or longer, of at least
             "moderate" intensity determined by Descriptor Differential Scale (DDS) > 7

          -  English-speaking, literate, able to understand the study and communicate with the
             study team

          -  Presently not a candidate for back surgery (one prior back surgery permitted if it was
             > 5 years ago and resulted in complete relief)

          -  Discontinued muscle relaxants, anticonvulsants, antidepressants, and opioids at least
             two weeks before screening and agree to discontinue throughout study (can remain on
             stable dose of NSAIDs)

          -  If female, not pregnant or lactating; agrees to use reliable contraception throughout
             the study, and has negative pregnancy test at screening

          -  Gives informed consent.

        Exclusion Criteria:

          -  A major coexisting medical illness (e.g., diabetes, renal or hepatic disease, chronic
             obstructive pulmonary disease, cancer, or class III or IV organic heart disease) that
             might increase risks of gabapentin, or major surgical or non-surgical intervention for
             any disorder within the past 12 months, since rehabilitation from treatment may
             confound study outcomes

          -  Significant coexisting orthopedic or pain problems; sciatica (pain, weakness, or
             dysesthesia solely in distribution of a lumbar spinal nerve, with or without reflex
             change) or back pain due to other disorders (e.g., fibromyalgia, vertebral fracture,
             osteomyelitis, metastatic cancer, rheumatoid arthritis; spinal stenosis)

          -  Diagnostic and Statistical Manual (DSM)-IV diagnosis of alcohol or other substance
             abuse or dependence (within the previous 12 months or positive urine toxicology at
             screening), current major depression or dysthymia; or lifetime bipolar disorder (I or
             II) (excluded because gabapentin is antidepressive and antimanic); or major anxiety
             disorder (e.g., panic disorder; or psychosis; or lifetime presence of cognitive
             impairment disorder (e.g. dementia)

          -  History of multiple adverse drug reactions or known allergy to gabapentin

          -  Use of psychotropics (e.g., antidepressants, anxiolytics), which would need to be
             continued during the study, or other drugs or agents (i.e., herbal preparations) which
             might interact with the study drug

          -  Prior treatment with the study drug

          -  Use of systemic corticosteroids or corticosteroid injections within three months of
             screening; or concurrent behavioral therapies, chiropractic treatment, or
             transcutaneous electrical nerve stimulation unit

          -  Renal impairment (creatinine > 1.8 mg/dL)

          -  Hepatic impairment (bilirubin > 1.5 X upper normal limit, or aspartate
             aminotransferase (AST) or alanine transaminase (ALT) > 2 X upper normal limit)

          -  Hematologic abnormality (hemoglobin < 9.4 gm/dL; absolute white blood cell (WBC) count
             < 3000/mm3, platelets < 100,000

          -  Pregnancy

          -  Immunosuppression

          -  Use of experimental drugs or participation in other clinical trials