Not surprising but definitely depressing

From the website,The Aids Beacon
I know, many of you are thinking, 'As long as it takes the pain away!' but this article is trying to make the point that the condition of neuropathy itself is very difficult to improve. You can help with the pain but you're not restoring nerve function in the process. In the meantime...more Brownie points for Cannabis apparently!

Most Recommended Treatments For HIV-Associated Sensory Neuropathy Are Ineffective
By Kieryn Graham
Published: Jan 5, 2011 5:17 pm

A review based on several clinical trials has found that most recommended treatments for HIV-associated sensory neuropathy are not effective. Only three pain relievers have demonstrated efficacy against HIV-associated sensory neuropathy: high-dose topical capsaicin, smoked marijuana, and an experimental protein that helps nerves grow.

“Our study is important as it has demonstrated that many drugs which are effective in other neuropathic pain states (and frequently used to treat painful HIV-SN [HIV-associated sensory neuropathy]) have no evidence of efficacy in painful HIV-SN,” said Dr. Tudor Phillips, lead author on the study, in correspondence with The AIDS Beacon.

Dr. Phillips also pointed out that, while the trials in included in the review found that high-dose topical capsaicin is effective, there is also a new trial underway that indicates it may be no more effective than a placebo. He also stated that the nerve growth protein will not be developed further because the required injections are too painful.

“This leaves very few evidence-based treatments available for clinicians to use. Consequently there is a real need to develop new treatment strategies for painful HIV-SN,” he added.

The authors suggested that one promising treatment for this condition may be the drug Cymbalta (duloxetine). Cymbalta is an antidepressant that is also used to treat diabetic neuropathy, a condition similar to HIV-SN. They also recommended that further studies be conducted with pain relievers in the opioid class, which includes drugs such as morphine, oxycodone (OxyContin), and hydrocodone.

HIV-associated sensory neuropathy (HIV-SN) is a nerve condition that causes pain, numbness, or tingling in the extremities. It can be caused both by the virus itself and by some HIV treatments, particularly the nucleoside reverse transcriptase inhibitors didanosine (Videx) and stavudine (Zerit).

The condition affects about 40 percent of all HIV patients on antiretroviral therapy and may become more common as more HIV-positive individuals begin antiretroviral treatment.

Currently, there are a variety of treatments prescribed to treat HIV-SN, but information on their efficacy for HIV-SN is limited because many of the drugs were designed to treat other conditions. For example, Lyrica (pregabalin) is approved to treat seizures, and amitriptyline is an antidepressant.

In their review, researchers sought to evaluate the effectiveness of these two drugs, as well as other commonly-used pain relievers, in treating HIV-SN. The review was based on 14 randomized, controlled clinical trials that investigated HIV-SN treatments.

Results showed that the only treatments to demonstrate greater efficacy than a placebo were smoked marijuana, high-dose topical capsaicin, and nerve growth factor. Topical capsaicin is a medicated cream or lotion for relieving joint and muscle pain that contains the active ingredient from chili peppers. Nerve growth factor is a small protein important for the growth, maintenance, and survival of certain nerve cells.

In contrast, the pain relievers amitriptyline, gabapentin (Neurontin) (a drug originally developed for the treatment of epilepsy that is now widely used as a pain reliever), Lyrica, prosaptide, peptide T, acetyl-L-carnitine, mexilitine (Mexitil), and low-dose topical capsaicin were no more effective in treating HIV-SN than placebos.

Lamotrigrine (Lamictal), another drug that was examined, may have been effective specifically in patients whose HIV-SN was linked to taking certain antiretrovirals known to cause the condition. For patients with HIV-SN in general, however, it was not more effective than a placebo.

Of the three drugs that demonstrated efficacy, only high-dose capsaicin is currently approved by the United States Food and Drug Administration (FDA). The FDA does not recommend smoked marijuana as therapy and nerve growth factor is not approved by the FDA.

The researchers did note that their results are somewhat limited by the lack of high-quality randomized, controlled trials investigating HIV-SN pain treatment. They added that their analysis was complicated by differing study designs and sizes.

The authors also pointed out that some of the trials included in the review did not take into account additional pain relievers being used by participants during the trials or whether participants had previously failed other pain relieving therapies. These conditions might have affected the results of the trials.