AcelRx starts cancer breakthrough pain program

Apr 22 2009

AcelRx Pharmaceuticals, Inc. has announced that it has initiated a Phase 2 clinical trial of ARX-02, a proprietary sublingual sufentanil NanoTab product candidate for cancer breakthrough pain control.

The primary objective of this multicenter, randomized, placebo-controlled, crossover study is assessment of safety, tolerability and efficacy of ARX-02 relative to placebo in cancer patients experiencing episodic breakthrough pain.

"We are pleased to have initiated the dosing of our first patient in this proof-of-concept study," states AcelRx Chief Executive Officer Thomas Schreck. "Developing a fastacting opioid with a shorter half-life than fentanyl for cancer patients who experience sudden breakthrough pain represents a significant step towards effectively treating pain while minimizing overall opioid exposure."

Pamela Palmer, MD, PHD, AcelRx Chief Medical Officer adds, "The pharmacokinetic profile of ARX-02 is optimal for this patient population. In contrast to fentanyl-based products, the highly consistent time to peak plasma concentration and plasma half-life of two to four hours produces a closer match of effective drug concentration with the breakthrough pain event and allows a high degree of safety if patients need to redose for a second breakthrough pain event."

Many patients with chronic cancer-related pain also experience episodes of severe pain that "breaks through" the regular pain medication. Typically the pain flare lasts approximately 15 - 60 minutes, and patients may experience several episodes per day. Currently, oral transmucosal fentanyl-based products are the only approved treatments for cancer breakthrough pain. These products have prolonged plasma half-lives that extend beyond four hours for most dosage strengths.

AcelRx is developing ARX-02, a novel sublingual sufentanil NanoTab product candidate, as a new treatment option for patients with breakthrough cancer pain. Sufentanil is a strong opioid that is approximately 5-10 times more potent than fentanyl yet has an 80-fold wider safety margin (therapeutic index), as determined in animal studies. The NanoTab is a very small tablet designed to allow the rapid uptake of sufentanil following placement under the tongue, maximizing transmucosal drug uptake and limiting the proportion of swallowed drug. ARX-02 enables rapid onset of pain relief with a consistent, relatively short duration of action, more closely matching the timing of a breakthrough pain episode.

http://www.acelrx.com