Efficacy of Co-administration of an NSAID With a Dopamine Agonist In Healthy Subjects

NCT02116790 | Withdrawn Phase 2

• 2 other identifiers: STU00083465R01DE022746
• Study Type: interventional
• Target: N/A
• Locations: 0 countries
• Sites: N/A

Brief Summary

Findings from the investigator's lab and others' show the involvement of the brain's mesolimbic circuitry in pain perception and evaluation, as well as during the transition from acute to chronic pain states in both humans and animals. Dopamine (DA) is one of the main neurotransmitters in this circuitry, and it is possible it could have an intimate role in pain processing, chronicity, and related anatomical and functional neuroplasticity. In this study, the investigators first need to know if the combination of l-dopa and Naproxen is safe and efficacious in humans with acute pain, and if so, at what doses. For the present study, healthy pain-free participants will be injected with a small bolus of capsaicin subcutaneously to induce acute cutaneous inflammatory pain. Capsaicin is ideal for this study because it causes a characteristic inflammatory response that is almost always accompanied with pain, has a well-validated dose-response curve, and has effects that will go away completely in a few hours after administration, causing no permanent damage to study subjects. Effects of capsaicin will be measured by changes (decreases) from baseline in thermal and tactile thresholds, as well as by verbally reported cutaneous pain levels (on a scale from 0-10). Participants will also be given study medication in the form of a placebo, one drug, or a combination of drugs before capsaicin injection to allow for any analgesic effects to peak before pain onset. For those receiving active medication, they will either receive Naproxen with placebo or the combination of naproxen and l-dopa (the latter of which will be in one of two different doses). This will allow the investigators to investigate (1) whether co-administration of naproxen and l-dopa has analgesic effects in low levels of acute pain in humans, (2) if this combination is pain-alleviating, whether it is equally as or more efficacious than naproxen, which is the clinical standard of treatment, and finally (3) what dose provides the most analgesia.

Conditions

Acute Pain

Keywords

acute; pain

Outcome Measures

Primary Outcomes (1)

• VAS pain scale

  1 Day

Study Arms (4)

Control Group

PLACEBO COMPARATOR

10 participants will be given two pills: both will be placebos

Drug: Placebo

Standard Treatment / Positive Control Group

ACTIVE COMPARATOR

10 participants will be given two pills: both will be Naproxen (each pill = 250mg, total dose = 500mg)

Drug: Naproxen

Experimental Group #1

ACTIVE COMPARATOR

10 participants will be given two pills: one will be Naproxen (250 mg) and the other will be of Sinemet (carbidopa/levodopa 12.5mg/50mg)

Drug: Naproxen; Drug: Sinemet

Experimental Group #2

ACTIVE COMPARATOR

10 participants will be given two pills: one will be Naproxen (250 mg) and the other will be of Sinemet (carbidopa/levodopa 25mg/100mg )

Drug: Naproxen; Drug: Sinemet

Interventions

Naproxen DRUG

Subjects will take one 250mg Naproxen capsule

Also known as: Aleve, Anaprox, Antalgin, Apranax, Feminax Ultra, Flanax, Inza, Midol Extended Relief, Nalgesin, Naposin, Naprelan, Naprogesic, Naprosyn, Narocin, Proxen, Soproxen, Synflex, Xenobid

Experimental Group #1; Experimental Group #2; Standard Treatment / Positive Control Group

Sinemet DRUG

Subjects will take one 12.5mg/50mg Sinemet.

Also known as: Carbidopa/levodopa, Levocarb, Pharmacopa, Atamet, Apo-Levocarb, Co-careldopa

Experimental Group #1

Placebo DRUG

Subjects will take two placebos.

Also known as: Sugar Pill

Control Group

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may not qualify if:

• Must be at least 18 years of age.
• Must be able to communicate (speak and write) in English.
• Must demonstrate that they understand what the study entails and requires of them.
• Must be able to dedicate the amount of time (\~3 hours) to participate in the study.
• History of chronic pain of any kind
• Have a current episode of acute pain of any kind (including stomach ache, headache, muscle ache, etc)
• History of psychiatric illness or brain injury
• History of substance abuse
• History of motor impairments
• History of another chronic disease (such as heart disease, celiac's, bronchial asthma, etc)
• Have a diagnosis of narrow-angle glaucoma
• History or presence of high blood pressure
• History or presence of melanoma cancer
• Currently on a high-protein diet
• Women who are pregnant, trying to get pregnant, or breastfeeding

Sponsors & Collaborators

• Northwestern University: lead
• National Institute of Dental and Craniofacial Research (NIDCR): collaborator
• National Institutes of Health (NIH): collaborator

MeSH Terms

Conditions

Acute Pain; Pain

Interventions

Naproxen; carbidopa, levodopa drug combination; Sugars

Condition Hierarchy (Ancestors)

Neurologic Manifestations; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Naphthaleneacetic Acids; Naphthalenes; Polycyclic Aromatic Hydrocarbons; Hydrocarbons, Aromatic; Hydrocarbons, Cyclic; Hydrocarbons; Organic Chemicals; Polycyclic Compounds; Carbohydrates

Study Officials

• Apkar V Apkarian, PhD

  Northwestern University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 2
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: February 17, 2014
• First Posted: April 17, 2014
• Study Start: May 1, 2014
• Primary Completion: January 1, 2015
• Study Completion: January 1, 2015
• Last Updated: October 10, 2014

Record last verified: 2014-10