Ulnar nerve block induced by the new local anesthetic IQB-9302 in healthy volunteers: a comparison with bupivacaine.

Abstract

We evaluated the duration of sensory anesthesia after blockade of the ulnar nerve of IQB-9302, a new local amide anesthetic, compared with bupivacaine. A double-blinded, randomized, cross-over study in 12 healthy volunteers aged 18 to 35 yr was performed. Three milliliters of 0.25% IQB-9302 was administered in one wrist and bupivacaine in the other. A week later, the blocks were repeated with a concentration of 0.5%. These concentrations were chosen because they seemed to be equipotent in previous studies. The duration of sensory anesthesia was the main variable measured; secondary outcomes were motor block, time to onset, and time to recovery from block. The duration of sensory block was similar for IQB-9302 and bupivacaine at a concentration of 0.25%; median and range: 409 min (0-800 min) for IQB-9302 and 258 min (0-665 min) for bupivacaine (95% confidence interval for the difference from -47 to 545, P = 0.82, Wilcoxon's test). The results with 0.5% were: 525 min (440-735 min) and 690 min (365-1098 min), respectively (P = 0.026). There were no significant differences in the other variables measured. No important adverse reactions were seen. We conclude that IQB-9302 is an effective new local anesthetic for blockade of ulnar nerve at the concentrations tested. IQB-9302 is a new local anesthetic that has shown a long duration of action and low cardiovascular toxicity in preclinical studies. We report the results of a phase I clinical trial to compare this new drug with bupivacaine for ulnar nerve block.