Safety and efficacy of transdermal buprenorphine and transdermal fentanyl in the treatment of neuropathic pain in AIDS patients.

BACKGROUND: Multifactor neuropathic pain is one of the most frequent symptoms in AIDS patients and analgesic treatment is primarily based on the use of drug combination of opioids, tricyclic antidepressants and antiepileptics. However, the chronic use of opioids in AIDS patients presents a risk due to the immunosuppressive action of these drugs. Until now, buprenorphine has been regarded as one of the safest opioid analgesics for the treatment of patients with compromised immune systems. To assess the suitability of transdermal fentanyl for the treatment of neuropathic pain in AIDS patients, the present study compares the efficacy, tolerability and the immunosuppressive effects of transdermal buprenorphine vs. fentanyl.
METHODS: Forty advanced AIDS patients (28 male and 12 female) with chronic peripheral neuropathic pain were enrolled onto this clinical trial. Neuropathic pain was assessed for its constituent types of pain (burning, stabbing and shooting), its overall intensity and allodynia; scores were awarded using the Neuropathic Pain Scale, expressed as 10 item VAS scores.
RESULTS: Both treatment groups showed statistically significant reductions in each of the individual types of neuropathic pain and allodynia (P<0.05; 95% CI: -14.7, -3.1) and significant improvements in Karnofsky Performance Status (P<0.05; mean value, 69; range: 40-90). Both buprenorphine and fentanyl were well tolerated. Neither buprenorphine nor fentanyl affected CD4+ or CD8+levels and both treatments, but particularly buprenorphine group, resulted in more stable CD4+ concentrations.
CONCLUSION: The high efficacy, tolerability and patient compliance of both buprenorphine and fentanyl make both these two opioids valid therapeutic options for the treatment of neuropathic pain in patients with AIDS.