A Study of SI-6603 in Patients With Lumbar Disc Herniation

Inclusion Criteria: * Patients with lumbar disc herniation (L4-L5 or L5-S1) as assessed by MRI and clinical symptoms corresponding to position of the impaired nerve root. * Patients assessed as positive in the SLR test. * Patients with sciatica in either leg. * Patients with no improvement from conservative treatment Exclusion Criteria: * Patients who have 2 or more lumbar disc herniations as assessed by MRI. * Patients in whom a rupture into the posterior longitudinal ligament is identified by MRI. * Patients who have received spinal injection, epidural injection, nerve block within 3 weeks prior to the time of informed consent. * Patients who have undergone lumbar operation, or lumbar percutaneous nucleotomy or lumbar intradiscal therapies