Sontra Completes SonoPrep Clinical Study

Rapid dermal anesthesia was achieved in a study using Sontra Medical's SonoPrep ultrasonic skin permeation followed by two minutes of active drug transport with iontophoresis, a needle-free method of delivering drugs through the skin using low-level electrical current, the company said.

In this randomized, prospective, internally controlled clinical study, 30 patients received three different types of treatments on their forearm with 2 percent topical lidocaine. Needle-stick pain was evaluated using the Visual Analogue Scale. The study evaluated SonoPrep ultrasonic skin pretreatment or a placebo (sham ultrasound) skin pretreatment followed by two minutes of iontophoresis, compared to 10 minutes of iontophoresis alone.

Pain scores from the SonoPrep treatment followed by two minutes of iontophoresis were equivalent to the 10-minute iontophoresis treatment. In this study, Sontra used an Iomed Phoresor Iontophoretic Drug Delivery System and 2 percent topical lidocaine with 1-10,000 epinephrine. SonoPrep pretreatment followed by 2 percent lidocaine application and two minutes of iontophoresis provided equivalent pain relief to 2 percent lidocaine applied over intact skin with 10 minutes of iontophoresis.