Study to Evaluate Analgesic Effect of Intravenous Administration of Kappa Agonist CR845 After Hysterectomy Surgery
Condition: Acute Pain
MeSH terms: Acute Pain
Study type: Interventional
Phase: Phase 2

Summary: 
      The purpose of this study is to determine the effectiveness and safety of single intravenous
      doses of the kappa opioid agonist CR845 in relieving pain in patients following
      laparoscopic-assisted hysterectomy surgery. The study protocol was divided into two parts
      with subjects either dosed with study drug the day following surgery (Cohort 1), or
      immediately after surgery (Cohort 2).
    

Detailed description: 
      Currently, the most widely used drugs to treat pain after surgery are opiates, such as
      morphine. Morphine works mainly by activating one of several types of opiate receptors that
      control some of our pain sensation - the so-called mu opiate receptors. These receptors are
      located in many areas of the brain and also outside of the brain. By activating these
      receptors, morphine provides significant pain relief, but also causes side effects that limit
      its use. Some of these side effects include: respiratory depression or arrest (slowed or
      stopped breathing), sedation (a state of calmness or extreme relaxation), euphoria (an
      exaggerated feeling of physical and mental well-being), constipation, nausea, vomiting, and
      drug addiction.

      In order to avoid the side effects of morphine and other mu opiates, the present experimental
      drug CR845 was designed to work at a different type of opiate receptor - called kappa - that
      can also provide pain relief, by acting on sensory nerves outside the brain. CR845 was
      designed to penetrate the brain much less than other opiate drugs, which should result in
      pain relief similar to that of morphine, but with fewer side effects. Because CR845 activates
      kappa receptors instead of mu receptors, the side effects are different than with a
      morphine-type drug. In particular, kappa opiates, such as CR845, do not cause respiratory
      depression or arrest, euphoria, constipation, drug tolerance, physical drug dependence or
      drug addiction. For these reasons, CR845 may present a distinct advantage over other opiates
      that are currently used for pain relief and post-operative pain in particular.
    

Intervention name(s): CR845; CR845; CR845; Placebo; Placebo
Intervention type(s): Drug; Drug; Drug; Drug; Drug
Intervention description(s): CR845 (0.024 mg/kg) administered the day after surgery (Day 1); CR845 (0.008 mg/kg) administered the day after surgery (Day 1); CR845 (0.040 mg/kg) administered immediately after surgery (Day 0); Matched placebo administered the day after surgery (Day 1); Matched placebo administered immediately after surgery (Day 0)
Other intervention name(s): Cohort 1: CR845 0.024 mg/kg; Cohort 1: CR845 0.008 mg/kg; Cohort 2: CR845 0.040 mg/kg; Cohort 1: Matched placebo; Cohort 2: Matched placebo
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Care Provider, Investigator)
Primary purpose: Treatment
Keywords: pain; acute pain; visceral pain; kappa agonist; opioid analgesics; peripheral nervous system agents; physiological effects of drugs; surgery; hysterectomy; post-operative; post-operative complications