Clinical Research Directory

Inclusion Criteria: 1. Aged 21 - 65 years old 2. Daily cigarette smoker (\>= 1 cigarette per day); 3. Smoke regular, filtered cigarettes or machine rolled cigarettes with a filter 4. No current or past use of Little Cigars 5. All other forms of nicotine must be used \<6 days out of the past 30 days. 6. Able to read and write in English 7. No serious cigarette smoking quit attempt or use of any FDA-approved smoking cessation medication in the prior 30 days 8. No plan to quitting smoking in the next 3 months Exclusion Criteria: 1. Women who are pregnant and/or nursing or trying to become pregnant 2. Unstable or significant medical condition in the past 3 months (e.g., recent heart attack or other serious heart condition, stroke, severe angina) 3. Respiratory diseases (e.g., exacerbations of asthma or Chronic Obstructive Pulmonary Disease (COPD), require oxygen, require oral prednisone), kidney (e.g., dialysis) or liver disease (e.g., cirrhosis), severe immune system disorders (e.g., uncontrolled HIV/AIDS, multiple sclerosis symptoms) or any medical disorder/medication that may affect participant safety or biomarker data 4. Uncontrolled substance abuse or inpatient treatment for that condition in the past 6 months 5. Exhaled Carbon Monoxide (CO) measurement of \>= 17 parts per million