Tolperisone in Acute Muscle Spasm of the Back
Condition: Back Pain; Acute Pain; Back Spasm Upper Back; Back Strain; Muscle Cramp; Muscle Spasm; Low Back Pain
MeSH terms: Muscle Cramp; Spasm; Hyperkinesis; Back Pain; Low Back Pain; Acute Pain
Intervention: Tolperisone; Placebo
Intervention description: TID; Placebo
Intervention MeSH terms: Tolperisone
Phase: Phase 2
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 415.0
Sex: All
Minimum age: 18 Years
Maximum age: 65 Years
Healthy volunteers: No

Summary:

      This is a double-blind, randomized, placebo-controlled, parallel group study of the efficacy
      and safety of tolperisone (a non-opioid) or placebo administered as multiple doses three
      times a day (TID) in approximately 400 male and female subjects experiencing back pain due to
      or associated with muscle spasm.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Ambulatory

          -  Current acute back pain and/or stiffness due to acute and painful muscle spasm
             starting within 7 days prior to study entry and more than 8 weeks after the last
             episode of acute back pain.

          -  Pain of 4 or more on the subject "right now" rating of pain intensity Numeric Rating
             Scale (NRS) scale of 0-10.

          -  Willing to discontinue all medication used for the treatment of pain or muscle spasm
             on study entry.

          -  Pain localized below the neck and above the inferior gluteal folds.

          -  Body mass index ranging between 18 and 35 kg/m².

        Exclusion Criteria:

          -  Unwillingness to stop taking pain or antispasmodic medication other than the study
             medication (specifically opioid use [e.g., Vicodin], barbiturates, and cannabis).

          -  Chronic pain for the previous 3 months or longer, on more days than not.

          -  Radicular pain in the lower extremity (i.e. pain radiating below the knee), sciatica
             pain down the leg, or pain below the knee (indicating a lumber radiculopathy);
             radicular pain in the upper extremity, radiating into the forearm or hand (indicating
             a cervical radiculopathy).

          -  Concomitant severe pain in a region other than the back.

          -  Spinal surgery within 1 year of study entry.

          -  Back pain due to major trauma (e.g., motor vehicle accident, fracture of bone) unless
             resolved for more than 1 year.

          -  Treatment of back pain ongoing with non-pharmacological therapy (e.g., acupuncture,
             chiropractic adjustment, massage, Transcutaneous Electrical Nerve Stimulation [TENS],
             physiotherapy).

          -  Subjects who test positive for alcohol by breathalyzer test.

          -  Unwilling to stop taking moderate to potent inhibitors of cytochrome P450 (CYP)
             isozymes CYP2D6 and CYP2C19, which are likely to cause drug interactions with
             tolperisone HCl (e.g., medications such as paroxetine and fluvoxamine).