Study to Evaluate the Pharmacokinetics, Pharmacodynamics, and Safety of Vonoprazan and Lansoprazole in Healthy Participants

Inclusion Criteria: * Participants must fulfill all the following inclusion criteria to be eligible for participation in the study: 1. Healthy, adult, male or female 18 - 55 years of age, inclusive, at screening. 2. Continuous nonsmoker who has not used nicotine-containing products for at least 3 months prior to the first dosing and throughout the study, based on participant self-reporting. 3. Body mass index (BMI) ≥ 18.0 and ≤ 32.0 kg/m\^2 at screening. 4. Medically healthy with no clinically significant medical history, physical examination, laboratory profiles, vital signs, or electrocardiograms (ECGs), as deemed by the principal investigator (PI) or designee. 5. Alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and gamma-glutamyl transferase (GGT) \< upper limits of the clinical laboratory reference range (one recheck is permissible). 6. A female of childbearing potential is either sexually inactive (abstinent as a life style) for 28 days prior to the first dosing and throughout the study or is using one of the following acceptable birth control methods: * hormonal oral contraceptives, vaginal ring, transdermal patch, or hormone releasing intrauterine device for at least 3 months prior to the first dosing and with either a physical (e.g., condom, diaphragm, or other) or a chemical (e.g., spermicide) barrier method from the time of screening and throughout the study. * Depot/implantable hormone (e.g., Depo-Provera®, Implanon®) for at least 3 months prior to the first dosing and throughout the study. In addition, female participants of childbearing potential will be advised to remain sexually inactive or to keep the same birth control method for at least 28 days after the last dose. 7. A female of non-childbearing potential has undergone one of the following sterilization procedures at least 6 months prior to the first dosing: * hysteroscopic sterilization; * bilateral tubal ligation or bilateral salpingectomy; * hysterectomy; * bilateral oophorectomy; or be postmenopausal with amenorrhea for at least 1 year prior to the first dosing and follicle stimulating hormone (FSH) serum levels consistent with postmenopausal status. 8. A non-vasectomized, male participant must agree to use a condom with spermicide or abstain from sexual intercourse during the study until 90 days after the last dosing. (No restrictions are required for a vasectomized male provided his vasectomy has been performed 4 months or more prior to the first dosing. A male who has been vasectomized less than 4 months prior to study first dosing must follow the same restrictions as a non-vasectomized male). 9. If male, must agree not to donate sperm from the first dosing until 90 days after the last dosing. 10. Understands the study procedures in the informed consent form (ICF), and be willing and able to comply with the protocol. Exclusion Criteria: * Participants must not be enrolled in the study if they meet any of the following criteria: 1. Is mentally or legally incapacitated or has significant emotional problems at the time of the screening visit or expected during the conduct of the study. 2. History or presence of clinically significant medical or psychiatric condition or disease in the opinion of the principal investigator (PI) or designee. 3. History of any illness that, in the opinion of the PI or designee, might confound the results of the study or poses an additional risk to the participant by their participation in the study. 4. History or presence of alcohol or drug abuse within the past 2 years prior to the first dosing. 5. History or presence of hypersensitivity or idiosyncratic reaction to the study drug(s), its excipients, related compounds, or lidocaine. 6. Clinically significant gastrointestinal (GI) disorder (e.g., gastric ulcer (GU), Gastroesophageal reflux disease (GERD), impaction, chronic constipation, inflammatory bowel disease, ischemic colitis, vascular intestinal atherosclerosis, previous bowel resection, bowel obstruction, bariatric surgery, cholecystitis \[including history of cholecystectomy\], and/or appendectomy). 7. Positive result for H. pylori breath test at screening. 8. Had diarrhea or vomiting within 48 hours prior to check-in. 9. Has nasal abnormalities that could affect pH probe insertion. 10. Cannot tolerate placement of the pH probe. 11. Female participants with a positive pregnancy test at screening or check-in or who are lactating. 12. Positive urine drug or alcohol results at screening or check-in. 13. Positive results at screening for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), or hepatitis C virus (HCV). 14. Seated blood pressure is less than 90/40 mmHg or greater than 140/90 mmHg at screening. 15. Seated heart rate is lower than 40 bpm or higher than 99 bpm at screening. 16. Fridericia's correction to the QT interval (QTcF) interval is \>460 msec (males) or \>470 msec (females) or has electrocardiogram (ECG) findings deemed abnormal with clinical significance by the PI or designee at screening. 17. Estimated creatinine clearance \<80 mL/min at screening. 18. The participant has serum creatinine \>1.22 mg/dL at screening or check-in. 19. Unable to refrain from or anticipates the use of: * Any drug, including prescription and non-prescription medications, herbal remedies, or vitamin supplements beginning 14 days prior to the first dosing and throughout the study. Medication listed as part of acceptable birth control methods will be allowed. After randomization, acetaminophen (up to 2 g per 24 hours) may be administered at the discretion of the PI or designee. Topical lidocaine may be administered for pH probe insertion. Hormone replacement therapy will also be allowed. * Any drugs known to be significant inducers of CYP3A4/5, CYP1A2, and/or CYP2C19 for 28 days prior to the first dosing and throughout the study. Appropriate sources will be consulted by the PI or designee to confirm lack of PK / PD interaction with study drug. 20. Has been on a diet incompatible with the on-study diet, in the opinion of the PI or designee, within the 30 days prior to the first dosing and throughout the study. 21. Donation of blood or significant blood loss within 56 days prior to the first dosing. 22. Plasma donation within 7 days prior to the first dosing. 23. Participation in another clinical study within 30 days prior to the first dosing. The 30 day window will be derived from the date of the last blood collection or dosing, whichever is later, in the previous study to Day 1 of Period 1 of the current study.