Placebo In Chronic Back Pain (Phase 2)

Visit 1 (week -3): Screening visit (90 min):

Participants will be evaluated with inclusion/exclusion criteria and complete the informed
consent documents. A medical/pain history will be taken and physical exam will be completed
by a physician and participants will be asked to rate their current back pain intensity.
Participants will complete a set of 10 questionnaires that will ask about health and medical
history, past and current pain levels, personality, and emotions. Participants will be
allowed to take breaks and walk around during this time so that participants don't get tired
while filling out questionnaires. Finally, participants will have blood drawn for screening
purposes including to see if kidneys and liver are functioning as they should (the
investigators will take 40 mL or about 8 teaspoons). Participants will be asked to return in
2 weeks for baseline magnetic resonance imaging (MRI) scans. Participants will be asked to
discontinue current pain medications 14 days prior to Visit 2 and take only the rescue
medication ("rescue" medication that is also known as acetaminophen/Tylenol ®), given for
pain during this time (see below) - this is so that the investigators can assess baseline
amount of pain. Participants will be informed that they may be randomized in the placebo
group and/or the no-treatment group (Visit 3) once one qualifies to continue in the study.
Participants must, therefore,a be willing and able to stop taking the medication for pain
for up to a maximum of 12 weeks during this study. Participants will be given acetaminophen
(500 mg, up to 4 times per day) to take for pain relief (as rescue medication), a dose that
can be continued throughout the study. Participants are free to stop participation at any
point in the study. Participants randomized into the treatment arm may receive the
anti-inflammatory drug naproxen, since it is known to increase the risk of stomach and
intestinal side effects, a combined naproxen/esomeprazole drug regimen will be given to
participants to provide some protection for these types of side effects.

Visit 2 (week -1): Baseline Scan (90 min):

Participants will rate their pain intensity, complete questionnaires, and undergo brain
scanning (anatomical and functional scans). Participants will receive medication, which can
be used if the pain becomes too much to handle (500 mg four times per day maximum). The
researcher will ask participants about how often participants used the "rescue" medication
and any changes in health they may have experienced since the last visit.

Visit 3 (week 0): Start of Treatment Period and Randomization (30-45 min):

Participants will rate their pain intensity and complete questionnaires. Participants will
be randomized into either a drug (placebo or naproxen and esomeprazole) treatment group or
no treatment group; if participants are assigned to a treatment group (active or placebo),
neither participants nor the clinical coordinator/assistant will know which group
participants are allocated in. Enough medication will be given to participants to last until
the next visit. The placebo group will receive two placebo capsules twice daily and the
active drug group will receive one naproxen capsule (500mg) and one esomeprazole capsule
(20mg) twice daily (morning and night) for the treatment period. The medication (Naproxen or
Placebo) needs to be taken with at least one full glass (8 oz) of water and the other
medication (Esomeprazole or Placebo) should be taken one hour before a meal. The researcher
will provide the study medication; if participants were randomized into the no treatment
group, participants will only receive rescue medication. The researcher will ask
participants about how often participants used the "rescue" medication and any side effects
participants experienced since Visit 2 took place. Additional "rescue" medication will be
given.

Visit 4 (week 3): Continuing Assessment (30-45 min). The procedures described for Visit 3
will be repeated during this visit. The researcher will ask participants about how often
they used the "rescue" medication and any side effects experienced since Visit 3 took place.
As well, the researcher will ask how often participants took the study medication (if in a
treatment group) and document the total pills ingested.

Visit 5 (week 6): End of Treatment/Start of Washout and Final Scan (60-90 min):

The procedures described for Visit 2 will be repeated during this visit. The researcher will
ask participants about how often and reliably participants took the medication (if in a
treatment group), as well as how often they used the "rescue" medication and any side
effects experienced since Visit 4 took place. Participants will only receive the "rescue"
medication for the upcoming 3 weeks.

Visit 6 (week 9): Final Visit/End of Washout (30-45 min):

Participants will return to complete questionnaires, but no brain scans will be done. The
researcher will ask participants about how often they used the "rescue" medication and any
side effects experienced since Visit 5 took place. If participants are in one of the
treatment groups, participants will be asked to return all of the study medication and
rescue medication at this time, and all treatment will be stopped at this visit.

Inclusion Criteria:

- History of low back pain for a minimum of 6 months with or without signs and symptoms
of radiculopathy

- Male or female, between the ages of 18 and 75 years, with no racial or ethnic
restrictions

- Must have a Visual Analog Scale (VAS) pain score of 5 mm (of 10 mm maximum) at the
screening visit (for which 0mm = no pain, and 10 mm = worst pain imaginable);

- Must be able to read and speak English and be willing to read and understand
instructions as well as questionnaires;

- Must be in generally stable health;

- Must sign an informed consent document after a complete explanation of the study
documenting that they understand the purpose of the study, procedures to be
undertaken, possible benefits, potential risks, and are willing to participate

- Must have, on average, 5/10 units (VAS scale) of pain over the course of a two-week
period prior to visit 1; rounding up from 4.5/10 is permissible.

- Must be willing to complete daily smart phone/computer app ratings.

Exclusion Criteria:

- Low back pain associated with any systemic signs or symptoms, e.g., fever, chills;

- Evidence of rheumatoid arthritis, ankylosing spondylitis, acute vertebral fractures,
fibromyalgia, history of tumor in the back;

- Other comorbid chronic pain or neurological conditions;

- Involvement in litigation regarding their back pain or having a disability claim or
receiving workman's compensation or seeking either as a result of their low back
pain;

- Diagnosis of current depression or psychiatric disorder requiring treatment, or such
a diagnosis in the previous 6 months;

- Beck Depression Inventory (BDI) Ia score greater or equal to 19 for two consecutive
completions; if the first score meets this criteria, the participant must be
re-tested before his/her next visit, but if the second score does not meet this
criteria, the participant will be included and followed closely throughout the study

- Use of therapeutic doses of antidepressant medications (i.e., tricyclic depressants,
SSRIs, SNRIs; low doses used for sleep may be allowed);

- Significant other medical disease such as unstable diabetes mellitus, congestive
heart failure, coronary or peripheral vascular disease, chronic obstructive lung
disease, or malignancy;

- History of gastrointestinal ulcer during the past year;

- History of myocardial infarction in the past year;

- Uncontrolled hypertension;

- Renal insufficiency;

- Allergic to, or non-tolerant of, NSAIDs;

- History of aspirin-sensitive asthma;

- Current use of recreational drugs or history of alcohol or drug abuse;

- Any change in medication for back pain in the last 30 days only applicable for visit
1

- High dose opioid prophylaxis, as defined as > 50mg morphine equivalent/day;

- Any medical condition that in the investigator's judgment may prevent the individual
from completing the study or put the individual at undue risk;

- In the judgment of the investigator, unable or unwilling to follow protocol and
instructions;

- Evidence of poor treatment compliance, in the judgment of the investigator;

- Intra-axial implants (e.g. spinal cord stimulators or pumps);

- All exclusion criteria for MR safety: any metallic implants, brain or skull
abnormalities, tattoos on large body parts, and claustrophobia;

- Pregnancy, or inability to use an effective form of contraception in women of
child-bearing age;

- Diabetes (Type I or Type II);

- Lactose intolerance or sensitivity to lactose