Chronic Pain Master Protocol (CPMP): A Study of LY3556050 in Participants With Chronic Low Back Pain

Randomized, Placebo-Controlled, Phase 2 Clinical Trial to Evaluate LY3556050 for the Treatment of Chronic Low Back Pain

This study is being done to test the safety and efficacy of the study drug LY3556050 for the treatment of chronic low back pain. This trial is part of the chronic pain master protocol H0P-MC-CPMP (NCT05986292) which is a protocol to accelerate the development of new treatments for chronic pain.

Inclusion Criteria:

• Have a visual analog scale (VAS) pain value ≥40 and <95 during screening.
• Have a history of daily pain for at least 12 weeks based on participant report or medical history.
• Have a value of ≤30 on the pain catastrophizing scale.
• Have a body mass index <40 kilograms per meter squared (kg/m²) (inclusive).
• Are willing to maintain a consistent regimen of any ongoing nonpharmacologic pain-relieving therapies (for example, physical therapy) and will not start any new nonpharmacologic pain-relieving therapies during study participation.
• Are willing to discontinue all medications taken for chronic pain conditions for the duration of the study.
• Have a history of low back pain for at least 3 months located between the 12th thoracic vertebra and the lower gluteal folds, with or without radiation.
• Have a history of low back pain as classified by the Quebec Task Force Category 1 through 3.
• Have stable glycemic control as indicated by a glycated hemoglobin (HbA1c) less than or equal to 10 at time of screening.
• Are men, or women able to abide by reproductive and contraceptive requirements.

Exclusion Criteria:

• Have second or third-degree atrioventricular (AV) heart block or AV dissociation or history of ventricular tachycardia.
• Have had a procedure within the past 6 months intended to produce permanent sensory loss in the target area of interest (for example, ablation techniques).
• Have surgery planned during the study for any reason, related or not to the disease state under evaluation.
• Have, in the judgment of the investigator, an acute, serious, or unstable medical condition or a history or presence of any other medical illness that would preclude study participation.
• There is an inability to rule out other causative or confounding sources of pain in the primary condition under study.
• Have had cancer within 2 years of baseline, except for cutaneous basal cell or squamous cell carcinoma resolved by excision.
• Have a substance use disorder as defined by the Diagnostic and Statistical Manual of Mental Disorders (5th edition; DSM-5; American Psychiatric Association).
• Have congenital QT prolongation or QT interval corrected for heart rate using Fridericia's formula (QTcF) interval measurement >450 milliseconds (msec) for male participants, >470 msec for female participants, or >480 msec for participants with bundle branch block.
• Have any clinically important abnormality at screening, as determined by investigator, in physical or neurological examination, vital signs, electrocardiogram (ECG), or clinical laboratory test results that could be detrimental to the participant or could compromise the study.
• Have a positive human immunodeficiency virus (HIV) test result at screening.
• Are, in the judgment of the investigator, actively suicidal and therefore deemed to be at significant risk for suicide.
• Have an intolerance to acetaminophen or paracetamol or any of its excipients.
• Have a history of alcohol, illicit drug, analgesic or narcotic use disorder within 2 years prior to screening.
• Have used a therapeutic injection (botulinum toxin or corticosteroids) in the 3 months prior to starting the washout period.
• Have history of or current osteoporotic compression fracture.
• Have had a recent major trauma (within 6 months of baseline).
• Have had surgical intervention for the treatment of low back pain in the past 6 months.
• Have a history within 2 years prior to screening or current evidence of syncope, presyncope, uncontrolled vertigo, or postural dizziness, judged to be clinically significant by the investigator.
• Have clinically significant active thyroid disease, including Hashimoto's thyroiditis.
• Are taking metformin therapy.
• Are pregnant or breastfeeding.