Qutenza Capsaicin

(...Treatments 2)

Given that this blog is dedicated to searching for facts, in as much as that is ever possible, this is the second treatment to come under the spotlight. There have been earlier posts concerning capsaicin but the more research you do, the more you come to the conclusion that this is one of the few treatments that has been proven to work for HIV patients with severe neuropathy.
Make no mistake about it, the Qutenza patches are strong and have to be applied with medical supervision and/or the greatest care but the statistics are promising.
It seems strange that science has come to the conclusion that two of the most efficient treatments for neuropathic pain are marijuana-based or chilli pepper-based but there you go, if it works don't knock it!
This is once again, a technical report but sometimes we need to learn to read these things in order to learn more about what's being prescribed for us.

AAPM: Capsaicin Patch Eases HIV Neuropathy Pain

By Ed Susman, Contributing Writer, MedPage Today
Published: March 26, 2011
Reviewed by Robert Jasmer, MD; Associate Clinical Professor of Medicine, University of California, San Francisco

WASHINGTON -- Difficult-to-treat HIV-associated neuropathic pain appears to be eased for at least three months with a one-time, 30-minute application of an 8% capsaicin patch (NGX-4010, Qutenza), researchers said here.

Patients reported a mean decrease of 27% in their Numeric Pain Rating Scale if they were treated with 8% capsaicin compared with a mean 15.7% decrease with the use of 0.04% capsaicin, an active control agent, said Stephen J. Brown, MD, of the AIDS Research Alliance in Los Angeles.

That difference translated to a significant reduction in pain scores (P=0.0026), he reported at the annual meeting of the American Academy of Pain Medicine.

"More than half of people with HIV-infection develop neuropathy, and about 30% to 40% of them have painful neuropathy," Brown told MedPage Today at his poster presentation. "To date, medications used to treat neuropathic pain have yielded disappointing results in large randomized controlled studies among HIV-associated neuropathy."
The only substances that have shown any impact on the pain appears to be the 8% capsaicin patch, smoked cannabis, and recombinant human nerve growth factor -- but none of these treatments has yet been approved by the FDA for that use, Brown noted.

Brown pooled data from two randomized, controlled studies in which 239 patients were treated with 8% capsaicin and were compared with 99 patients who received the active control -- a capsaicin treatment that is stronger than over-the-counter capsaicin, a drug derived from hot chili peppers.

The patients were assessed after three months following application of the capsaicin patch.

Both studies were sponsored by NeurogesX of San Mateo, Calif. The company is seeking an indication for treatment of HIV-associated neuropathy with the patch, which is approved for other neuropathy indications.

Patients were treated with 4% lidocaine for 60 minutes before the application of the patch. "This treatment can be painful," said David Walk, MD, of the University of Minnesota in Minneapolis. Walk has worked on other studies of the 8% capsaicin patch, but was not involved in Brown's HIV study.

"Even with the lidocaine that is delivered before the patch is applied, patients report some pain associated with the patch for as long as a week afterwards, so we usually send them home with analgesia to cover that period, Walk told MedPage Today.

He said that he prefers that that application be performed in the office setting, to assure that the patches are positioned and applied correctly and to treat any acute pain that might occur.

In Brown's study with HIV patients, about 36% of them also reported a reduction of 30% or more in the Numeric Pain Reporting Scale compared with 22% of those patients on the active control agent (P=0.0051).

About 37% of the patients on the 8% capsaicin patch reported a greater than two-point reduction in the pain scores compared with 24% of those on the active control agent (P=0.0284).

On the Patient Global Impression of Pain, about 36% of those taking the 8% capsaicin patch reported that their pain was either much improved or very much improved compared with 22% of the patients on the active control (P=0.0162), Brown reported.

"These integrated analyses show that a single 30-minute NGX-4010 application can reduce neuropathic pain due to HIV-associated neuropathy for 12 weeks," Brown said.

Brown said that 98% of the patients were able to tolerate at least 90% of the intended duration of patch application.

The most common side effects were application site pain and erythema. These mild-to-moderate adverse events were transient and resolved spontaneously within a week, Brown reported.

"I think this patch has promise in HIV-associated neuropathy," Erik Shaw, DO, of Shepherd Pain Institute in Atlanta, told MedPage Today. "This is one application and it appears to be effective for at least three months. I think we are going to see more use of this patch in other neuropathy conditions."

Brown's study was sponsored by NeurogesX.

Walk has disclosed financial relationships with Eli Lilly and Company, Pfizer, Aldoc Pharmaceuticals, AstraZeneca, Johnson & Johnson, and NeurogesX.

Shaw disclosed financial relationships with Azur, NeurogesX, Boston Scientific, and Forest Laboratories.

Primary source: American Academy of Pain Medicine
Source reference:
Vanhove G, et al "Efficacy of NGX-4010 (Qutenza), a capsaicin 8% patch, applied for 30 minutes in patients with HIV-associated neuropathy: Results of integrated analyses" AAPM 2011; Abstract 139.