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