Safety, tolerability and efficacy of intraoperative ALGRX 4975 in a randomized, double-blind, placebo-controlled study of subjects undergoing bunionectomy

The Effect of Wound Instillation of a Novel Purified Capsaicin Formulation on Postherniotomy Pain: A Double-Blind, Randomized, Placebo-Controlled Study

“…The primary end-point was average daily VAS scores, assessed during movement upon arising in the morning and retiring in the evening, during the first week after surgery. Pain scores during the first week were chosen as a primary outcome based upon pilot studies [12][13][14][15] and the theoretical duration of c-fiber inhibition, 9 assuming high pain score in this period as seen in previous groin hernia studies. 4 Secondary end-points included: time to supplemental medication usage, average pain scores at individual intervals for the first 4 wk after surgery, area under the curve (AUC) pain scores from 4 h postoperatively to day 7 evening (AUC day 7 ), AUC during the first 4 wk after surgery (AUC week 4 ), and when (day and time) the AUC pain scores were no longer significantly different.…”

“…The active study medication was purified (Ն98%) capsaicin (ALGRX 4975, Anesiva, Inc., South San Francisco, USA). Based upon safety and efficacy data from pilot studies, [12][13][14][15] an instillation of 1000 g purified capsaicin was chosen. Purified capsaicin was supplied as an open-label stock solution, and diluted with water for a maximum of 4 h before administration.…”

Emerging targets in treating pain

“…high blood pressure, respiratory effects). The compound 4975 (Adlea) demonstrated significant pain reduction for various orthopedic conditions after a single local injection [152][153][154]. Topical formulations are available over the counter and are effective in treating peripheral neuropathic pain [5 && ], but did not benefit patients with interstitial cystitis and painful bladder syndrome [151].…”

Resiniferatoxin for Pain Treatment: An Interventional Approach to Personalized Pain Medicine

“…Subsequent to a pre-operative block with lidocaine, the incision site for bunionectomy was superfused intraoperatively with 1000 μg of capsaicin in 4 ml of vehicle immediately before wound closure. This produced a reduction in post-operative opioid use and a significant reduction in mean visual analog scale rating of pain (a decrease of 12.7 and 14.2 mm) at 8 and 24 hours post-operation, a phenomenon not seen during the remaining two to 14 days of the study [63]. A larger study of hernia repair also using 1,000 μg of capsaicin showed significant analgesia from incisional infiltration with capsaicin [64].…”