Raptis, E., Vadalouca, A., Stavropoulou, E., Argyra, E., Melemeni, A., & Siafaka, I. (2014). Pregabalin vs. opioids for the treatment of neuropathic cancer pain: A prospective, head-to-head, randomized, open-label study. Pain Practice, 14, 32–42.
To determine the efficacy and safety of increasing opioid doses versus increasing doses of an adjuvant for patients with definite neuropathic cancer pain (i.e., neuropathic pain that occurred as a result of the disease, the treatment, or both). The goal was to achieve a 30% or more decrease in the visual analog scale (VAS) score compared to baseline.
One hundred and twenty patients were divided via simple randomization into two groups. Baseline data were collected on all 120 patients (i.e., VAS score, meds, and full assessment). The first group was prescribed a starting dose of pregabalin at 75 mg per day and titrated up by 75 mg every third day as needed up to 600 mg per day divided into two doses, until adequate pain relief was achieved or adverse effects were noted. The second group was given 25 mcg per hour fentanyl patch and increased by 25 mcg per hour every 72 hours up to a max dose of 150 mcg per hour until adequate pain relief was achieved or adverse events were noted. Both groups had rescue oral morphine as needed.
Changes in VAS scores showed no difference between groups, but the percentage change in these scores showed a significant reduction for the patients on pregabalin (-58% versus -50%). A greater percentage of patients on pregabalin achieved the study primary endpoint of at least a 30% reduction in pain VAS score (73.3% with pregabalin, 36.7% with fentanyl, p < .0001). No significant difference was seen in the proportion of patients needing rescue medication.
For these patients with neuropathic pain, no significant differences were seen in efficacy of adjuvant pregabalin versus increasing opioid medication for pain control.
I find the results of this study to be useful for oncology professionals working with patients with neuropathic cancer pain, whether from the disease, the treatment, or both. A similar study using tramadol versus pregabalin for neuropathic cancer pain may be of value.