Drug-Drug Interaction Study With AZD9291 and Omeprazole in Healthy Volunteers

For inclusion in the study volunteers must fulfil the following criteria. 1. Provision of signed and dated informed consent prior to any study-specific procedures. 2. Healthy male volunteers aged 18 to 55 years. (Healthy as determined by medical history, physical examination, laboratory parameters, ECG, and eye examination performed before the first administration of investigational product.) 3. Body mass index between 19 and 30 kg/m2, and body weight between 50 kg and 100 kg, inclusive. 4. Veins suitable for cannulation or repeated venepuncture. 5. Volunteers must be willing to use reliable methods of contraception (condom and spermicide), even if their partners are postmenopausal, surgically sterile, or using an effective hormonal method of contraception or intrauterine coil. In addition, volunteers must agree to continue to take similar contraceptive precautions and avoid sperm donation for 6 months after the last administration of AZD9291. Volunteers must not enter the study if any of the following exclusion criteria are fulfilled: 1. Involvement in the planning and/or conduct of the study (applies to both AstraZeneca and Quintiles staff). 2. Previous enrollment in the present study. 3. History of any clinically significant disease or disorder which, in the opinion of the Investigator, may either put the healthy volunteer at risk because of participation in the study, or influence the results or the healthy volunteer's ability to participate in the study. 4. History or presence of gastrointestinal, hepatic, or renal disease or surgical procedure or any other condition known to interfere with the absorption, distribution, metabolism, or excretion of drugs. 5. Any clinically significant abnormalities in physical examination, vital signs (supine blood pressure \>140 mmHg systolic, \>90 mmHg diastolic, or pulse rate ≤35 or ≥100 beats per minute), or clinical laboratory assessment as judged by the Investigator. 6. Acute illness, surgical procedures, or trauma from within 2 weeks before enrollment until first administration of investigational product (IP). 7. Volunteers who have received live or live-attenuated vaccine in the 2 weeks prior to dosing. 8. Volunteers with active malignancy or neoplastic disease in the previous 12 months. 9. A suspected/manifested infection according to International Airline Transportation Association (IATA) Categories A and B infectious substances. 10. Positive results on screening tests for serum hepatitis B surface antigen (HBsAg), hepatitis C antibody, or human immunodeficiency virus (HIV). 11. Any clinically important abnormalities in rhythm, conduction, or morphology of resting ECG, as judged by the Investigator. 12. Known or suspected history of significant drug abuse as judged by the Investigator. 13. Positive screen for drugs of abuse or cotinine (nicotine level above 400 ng/mL) at screening or positive screen for alcohol, drugs of abuse, or cotinine on admission in Period 1 or Period 2. 14. History of alcohol abuse or excessive intake of alcohol, defined as regular weekly intake of greater than 21 units of alcohol in men (Note: 1 unit=25 mL spirits, 125 mL wine, or 250 mL beer or lager). 15. History of severe allergy/hypersensitivity or ongoing allergy/hypersensitivity, as judged by the Investigator, or history of hypersensitivity to AZD9291, its excipients, or drugs with a similar chemical structure or class. 16. History of hypersensitivity to omeprazole, its excipients, or drugs with a similar chemical structure or class. 17. Use of any prescribed or nonprescribed medication, including drugs with hepatic enzyme-altering properties, such as St John's Wort, antacids, analgesics, herbal remedies, vitamins, and minerals during the 4 weeks (or longer depending on the medication's half-life) prior to the first administration of AZD9291 is not permitted. Occasional use of paracetamol (acetaminophen) and nonsteroidal nasal decongestant is permitted at the discretion of the Investigator. 18. Any intake of grapefruit, grapefruit juice, Seville oranges, Seville orange marmalade, or other products containing grapefruit or Seville oranges within 7 days of the first administration of IP. 19. Blood donation within 1 month of screening or any blood donation/blood loss greater than 500 mL during the 3 months prior to screening. 20. Use of another new chemical entity (defined as a compound which has not been approved for marketing) or participation in any other clinical study (including methodology studies where no drugs were given) within 3 months of the first administration of IP in this study. 21. Current smokers or those who have smoked or used nicotine products within the previous 3 months. 22. Planned inpatient surgery, dental procedure, or hospitalisation during the study.