Chronic Pain Master Protocol (CPMP): A Study of LY3556050 in Participants With Diabetic Peripheral Neuropathic 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 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 pain medications taken for chronic pain conditions for the duration of the study.
• Have daily symmetrical foot pain secondary to peripheral neuropathy present for at least 6 months and as diagnosed through use of the Michigan Neuropathy Screening Instrument Part B ≥3 (©University of Michigan).
• Have a history and current diagnosis of type 1 or type 2 diabetes mellitus.
• Have stable glycemic control as indicated by a glycated hemoglobin ≤11 at time of screening.
• Are men, or women able to abide by reproductive and contraceptive requirements.

Exclusion Criteria:

• 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.
• Have a substance use disorder as defined by the Diagnostic and Statistical Manual of Mental Disorders (5th edition; DSM-5; American Psychiatric Association).
• Have had cancer within 2 years of baseline, except for cutaneous basal cell or squamous cell carcinoma resolved by excision.
• Are, in the judgment of the investigator, actively suicidal and therefore deemed to be at significant risk for suicide.
• Have a positive human immunodeficiency virus (HIV) test result at screening.
• 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 a current drug-induced neuropathy, for example, due to some types of chemotherapy, or other types of peripheral neuropathy.
• Have known hereditary motor, sensory or autonomic neuropathies.
• 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. Metformin Exception Limited dosages of metformin are allowed in this study. Additional exclusion criteria for participants taking metformin.

  • Have a history or presence of lactic acidosis.
  • Have a history or presence of severe hepatic disease including cirrhosis.
  • Have uncontrolled or unstable congestive heart failure.
  • Are taking carbonic anhydrase inhibitors if also taking metformin.
  • Have had a change in metformin therapy in the last 12 weeks.
  • Have not maintained a stable dose of glucose-lowering agents other than metformin before randomization.
  • Are pregnant or breastfeeding.
  • Have fibromyalgia.