Maximizing Analgesia to Reduce Pain in Knee Osteoarthritis

Phase 2

Completed

Brief Summary: This research is being done to evaluate whether combining medications that are FDA approved, but have not yet been approved for combination treatment, can be effective in reducing pain.

Detailed Description: This study will evaluate whether a combination of pharmacotherapies can effectively alleviate pain. Subjects will complete two screening sessions before completing four study sessions that will occur once weekly. Participants will receive double blind doses of study medications the morning of each experimental session day and will undergo standardized pain testing, physical functioning assessment, blood draws, ratings of drug effects and cognitive testing.

Recruitment & Eligibility

Inclusion Criteria

Diagnosis of knee osteoarthritis
Urine sample tests negative for common illicit substances of abuse (e.g., cannabis)
Medically cleared to take study medications
Are not pregnant or breast feeding
Willing to comply with the study protocol.

Exclusion Criteria

Pain other than Knee Osteoarthritis
Taking opioids for pain
Prescribed and taking gabapentinoid, Tricyclic Antidepressants (TCA), venlafaxine, duloxetine, stimulants or benzodiazepines
Presence of any clinically significant medical/psychiatric illness judged by the investigators to put subject at elevated risk for experiencing an adverse event
Known allergy to the blinded study medications

Arm && Interventions

Group	Intervention	Description
Arm 3	Blinded study medication	Blinded study medication. Participants will be asked to complete standardized pain testing procedures, do brief physical functioning testing, undergo blood draws and complete questionnaires and cognitive testing at multiple points over the course of each study visit.
Arm 1	Blinded study medication	Blinded study medication. This is a within-subject study so all session procedures will be identical. The specific medications administered that study day will be the only change each session. Study days will last approximately 8 hours and will be conducted on an outpatient basis. Participants will be asked to complete standardized pain testing procedures, do brief physical functioning testing, undergo blood draws and complete questionnaires and cognitive testing at multiple points over the course of each study visit.
Arm 2	Blinded study medication	Blinded study medication. Participants will be asked to complete standardized pain testing procedures, do brief physical functioning testing, undergo blood draws and complete questionnaires and cognitive testing at multiple points over the course of each study visit.
Arm 4	Blinded study medication	Blinded study medication. Participants will be asked to complete standardized pain testing procedures, do brief physical functioning testing, undergo blood draws and complete questionnaires and cognitive testing at multiple points over the course of each study visit.

Primary Outcome Measures

Name	Time	Method
Largest Change From Baseline on Clinical Pain Rating	8 hour study session	The study will measure whether blinded study medications change clinical pain ratings (0-100 pain rating scale). Higher score indicates worse outcome. Biggest difference from baseline over the entire session is reported.

Secondary Outcome Measures