Safety Study of DS-5565 for Treatment of Fibromyalgia Pain in Subjects With Chronic Kidney Disease

Abbreviations: alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatinine clearance \[(CrCL) determined by the central laboratory using the Cockcroft-Gault equation\], upper limit of normal (ULN), Columbia-Suicide Severity Rating Scale (C-SSRS) Inclusion Criteria: * Age ≥ 18 years * Able to give written informed consent * Able to complete patient-reported questionnaires per the Investigator's judgment * Estimated CrCl between 15-59 mL/min from serum creatinine by the central laboratory using the Cockcroft-Gault equation * Fibromyalgia meeting American College of Rheumatology criteria for FM: * Widespread pain index (WPI) ≥ 7 and symptom severity (SS) scale score ≥ 5 or WPI 3 to 6 and SS scale score ≥ 9, * Pain in at least 11 of 18 specific tender point sites, * Symptoms have been present at a similar level for at least 3 months, and * The subject does not have a disorder that would otherwise explain the pain * Average Daily Pain Score of ≥ 4 on the 11-point numeric rating scale (NRS) over the 7 days prior to randomization (based on completion of at least 4 daily pain assessments during the 7-day baseline period prior to randomization) * Women of child bearing potential (WOCBP) must be using adequate methods of contraception to avoid pregnancy during the study and for 4 weeks after study completion. Exclusion Criteria: * Need for ongoing use of concomitant chronic pain medications or any new non-pharmacological pain management techniques that may confound assessments of efficacy and/or safety, including neurolytic treatments (destruction of nerves by chemicals, heat, cold) or surgery, intrathecal pumps, spinal cord stimulators or psychological support within the previous year. Also excluded: topical capsaicin within 6 months; or systemic corticosteroids within 3 months of baseline period. * Unable to undergo pre-study washout of prohibited concomitant medications * Subjects with recent history (i.e., within 1 year prior to screening) of alcohol abuse or illicit drug use (cocaine, heroin, marijuana \[including medical, prescribed\], etc.) * Use of any selective serotonin reuptake inhibitor (SSRI), unless the subject has been on a stable dose for ≥ 90 days prior to screening and is not anticipated to need any dose adjustment during the course of the study * Subjects with severe or uncontrolled depression that, in the judgment of the Investigator, makes the subject inappropriate for entry into the study * Significant neurological or psychiatr…