Evaluating the Efficacy and Safety of Extended Release Hydromorphone (Exalgo) in Patients With Neuropathic Pain

Neuropathic pain state is usually refractory to most analgesic regimens and requires polypharmacy for symptomatic relief. Current treatment options for neuropathic pain include both oral and topical medications. Most commonly prescribed oral treatments include antidepressants (eg, amitriptyline, desipramine, and duloxetine), antiepileptics (eg, gabapentin, pregabalin), and opiates such as tramadol and morphine. Current topical treatments include the lidocaine patch and the capsaicin patch. Many patients have inadequate pain relief in spite of these treatment options.

Currently, there are no treatments available for treatment of neuropathy itself other than treating the underlying cause and addressing the symptomatic relief for pain. Current drug therapies for neuropathic pain provide inadequate pain relief and undesirable side effects including sedation and cognitive dysfunction. It is not uncommon to use a combination of agents for the treatment of neuropathic pain to minimize the side effects. Although treating the mild to moderate pain may be relatively easy, it is very challenging for severe neuropathic pain. Although the use of opiates for neuropathic pain is well accepted, it remains controversial because of the potential for abuse and diversion.

Inclusion criteria

• individuals with chronic pain of more than 6 months duration
• pain is determined to be secondary to a documented neuropathy
• patients who are tolerant of opiates (60 mg of morphine or equivalent for at least one week)
• male or female patients aged 18-75 yrs and have signed a written informed consent form and privacy statement
• female patients of child-bearing potential must be using an acceptable form of birth control

Exclusion criteria

• pregnant or lactating women
• allergy to morphine or its derivatives
• history of alcohol or substance abuse in the last 3 yrs
• participation in any other clinical trial in the last 30 days
• uncontrolled pain
• patient who is deemed to be medically unstable by principal investigator
• history of severe lung disease or asthma that is deemed medically significant by principal investigator