Study to Investigate the Efficacy and Safety of SC0023, in Adults With Refractory or Unexplained Chronic Cough

Inclusion Criteria: * Males and females between 18-80 years * Capable of giving signed informed consent * Diagnosed with RCC (including unexplained chronic cough) for at least 6 months and at least 4 coughs per hour on average during awake hours at Screening. * Score ≥ 40 mm on cough severity VAS at screening. * Normal FEV/FVC * Women of child-bearing potential must use a highly effective contraception method during the study and for at least 14 days after the last dose. Exclusion Criteria: * Current smoker/vaper (all forms of smoking and inhaled substances, including, cannabis/tobacco smoke and nicotine vapors) or individuals who have given up smoking within the past 6 months, or those with \>20 pack-year smoking history. * Diagnosis of Chronic Obstructive Pulmonary Disease (COPD) bronchiectasis, idiopathic pulmonary fibrosis or uncontrolled asthma. * Respiratory tract infection within 4 weeks before screening. * History of malignancy in the last 5 years. * History of alcohol or drug abuse within the last 3 years. * Opioid use in last 7 days of screening. * History of a positive serologic test for, hepatitis B virus surface antigen, or hepatitis C virus. * Previous participation in clinical trial in last 30 days or 6-half lives of test drug activity. * Use of prohibited medications anti-tussive therapy, gabapentin, pregabalin, baclofen, tricyclics, systemic corticosteroids, ACE inhibitors, beta blockers. * Use of dietary supplements containing magnesium for the duration o…