Subcutaneous Lidocaine For Cancer-Related Pain

• Reduction in worst pain intensity or reduction in 24hr opioid dose of at least 30% without worsening of pain scores [ Time Frame: within 48 hours of infusion and lasting a minimum of 7 days ] [ Designated as safety issue: No ]

  The primary outcomes measure is a binary variable indicating whether lidocaine caused a reduction in cancer pain within 48 hours of infusion and lasting a minimum of 7 days. Lidocaine will be considered to have caused reduction in cancer pain if the subject had either one of the following episodes lasting a minimum of 7 days:

  1. A 2-point reduction in severity of pain as assessed by the worst pain score in the last 24 hours (question 3) of the Brief Pain Inventory - Short Form (BPI), compared to the BPI pain score at baseline.

     Or:

  2. ≥30% reduction in 24-hour opioid dose.
  
  

• Incidence of adverse events. [ Time Frame: At least 6 weeks: for 3 weeks following each treatment (lidocaine or placebo) at least 3 weeks apart ] [ Designated as safety issue: Yes ]
  Incidence of adverse events.
  
  
• Quality of Life [ Time Frame: At least 6 weeks (duration of study) ] [ Designated as safety issue: No ]
  Effect of Lidocaine infusion on QOL parameters as measured by the Patient Outcome Scale (POS) Questionnaire
  
  
• Duration of response to lidocaine infusion. [ Time Frame: At least 6 weeks (duration of study) ] [ Designated as safety issue: No ]
  Duration of response to lidocaine infusion.
  
  

Ten mg/kg of lidocaine will be infused subcutaneously via a Baxter infusor over a 5.5 hour period in ambulatory adult cancer patients with aworst pain score of at least 4 out of 10 despite therapy with at least one opioid plus appropriate oral adjuvant analgesic(s).

A clinically useful reduction in pain is defined by either a 2-point reduction (on a 0-10 scale) in the worst pain experienced over a 24-hour period, or a ≥30% reduction in 24-hour opioid requirement.

The secondary objectives are 1) to determine whether any significant toxicities occur as a result of the infusion. For this study significant toxicity is considered as any adverse event which either leads to the infusion being terminated, or which leads to medical intervention, such as prescribing of another medication or equivalent treatment, 2) to determine the effect of Lidocaine infusion on QOL parameters as measured by the Patient Outcome Scale (POS) Questionnaire and 3) to determine the duration of response to lidocaine infusion.