 This is a prospective cohort study, open-label, uncontrolled proof of concept trial. The trial objective is to evaluate the analgesic tolerability, safety and activity of IDN 5243 3-glycosyl-3-O-demethylthiocolchicine derivativeadministered intramuscularly at 4 mg b.i.d. for 5 days in the morning 8.00-10.00 AM and in the evening 6.00-8.00 PM in subjects with Low Back Pain LBP. 