A Study of the Safety, Tolerability, and Pharmacokinetics of SM04690 Injectable Suspension Following Single Intradiscal Injection in Subjects With Degenerative Disc Disease

Inclusion Criteria:

- Degenerative disease in a maximum of two and a minimum of one lumbar disc (L4/L5 or
L5/S1)

- Persistent low back pain due to DDD for at least 3 months prior to study start

- Full understanding of the requirements of the study and willingness to comply with all
study visits and assessments

- Subjects must have read and understood the informed consent form, and must have signed
it prior to any study-related procedure being performed

Exclusion Criteria:

- Women who are pregnant, lactating, or have a positive pregnancy result at study start

- Women of child bearing potential who are sexually active and are not willing to use a
highly effective method of birth control during the study period

- Males who are sexually active and have a partner who is capable of becoming pregnant,
neither of whom have had surgery to become sterilized or whom are not using a highly
effective method of birth control

- Body mass index (BMI) > 35

- Previous participation in a Samumed clinical trial investigating SM04690

- History of compression fractures and/or osteoporosis

- Any herniation in the lumbar spine as identified by MRI

- Congenital or acquired diseases leading to spine deformations

- History of hypersensitivity or allergies to any ingredient of the study medication

- Participation in a clinical research trial that included the receipt of an
investigational product or any experimental therapeutic procedure, or an observational
research trial related to DDD within 8 weeks prior to any study injection, or planned
participation in any such trial; the last date of participation in the trial, not the
last date of receipt of investigational product, must be at least 8 weeks prior to
study start

- Poor peripheral venous access

- Any contraindications to MRI according to MRI guidelines

- History of malignancy; however, subjects with prior history of in situ cancer or basal
or squamous cell skin cancer, completely cured, are eligible.

- Any diagnosed psychiatric condition that includes, but is not limited to, a history of
mania, bipolar disorder, psychotic disorder, schizophrenia, schizoaffective disorder,
major depressive disorder, or generalized anxiety disorder

- Prior surgical procedures (e.g., discectomy, intradiscal electrothermal therapy,
intradiscal radiofrequency, artificial disc replacement, and interbody fusion) on the
lumbar spine

- Any planned or elective surgery during the study period

- Any known active infections, including hepatitis B or hepatitis C infection, and/or
infections that may compromise the immune system such as human immunodeficiency virus
(HIV)

- Current or prior history of any spinal infection (i.e., discitis, septic arthritis, or
epidural abscess)

- Any lumbar intradiscal injection procedure (e.g., injection of corticosteroids,
methylene blue, dextrose, etc.), myelograms, discography, and/or lumbar epidural or
transforaminal injections with corticosteroids or nerve-blocking anesthetics (e.g,
lidocaine, bupivacaine) within 3 months prior to study start

- Any electrotherapy (i.e., transcutaneous electrical nerve stimulation [TENS] unit) or
acupuncture for DDD within 4 weeks prior to study medication injection

- History of or current/pending disability claim, workers' compensation, or
litigation(s) related to back pain/injury

- Subjects who are immediate family members (spouse, parent, child, or sibling;
biological or legally adopted) of personnel directly affiliated with the study at any
investigative site, or are directly affiliated with the study at any investigative
site

- Subjects employed by Samumed, LLC, or any of its affiliates or development partners
(that is, an employee, temporary contract worker, or designee) responsible for the
conduct of the study, or who are immediate family members (spouse, parent, child, or
sibling; biological or legally adopted) of said employees responsible for the conduct
of the study