NCT05345509

Who might be able to join this trial:

• You are a generally healthy man or woman between 18 and 55 years old.
• You are a non-smoker or only smoke occasionally (fewer than 10 cigarettes or the nicotine equivalent per week), and you are willing to not smoke while staying at the study site.
• Your body weight and height fall within a specific healthy range (BMI between 18.0 and 32.0), and you weigh at least 55 kg if male or at least 50 kg if female.
• If you are a man who is sexually active with a male partner, you must be willing to use a condom throughout the study.
• If you choose not to have sexual intercourse as your normal lifestyle, you may be eligible under this condition.
• You are willing to avoid pain relievers such as ibuprofen, naproxen, aspirin, and similar drugs from the start of screening until the end of the study.
• You are willing and able to sign a consent form agreeing to take part after having the study fully explained to you.

Who may not be able to join:

• You had any notable health problems found during your physical check-up at screening.
• Your blood test results showed significant abnormalities, or you tested positive for HIV, hepatitis B, or hepatitis C.
• You are pregnant, tested positive on a pregnancy test at screening or just before the study starts, or you are currently breastfeeding.
• You tested positive for drugs or alcohol at screening or just before the study starts.
• You have a history of any form of cancer or tumour growth.
• You have had a significant allergic reaction (such as severe drug reactions, anaphylaxis, swelling, or hypersensitivity) to donepezil, dimenhydrinate, benzatropine, related medicines, or any ingredient in the study drugs.
• You have an inherited condition affecting how your body handles certain sugars, such as galactose intolerance, lactase deficiency, or glucose-galactose malabsorption (this applies to one part of the study only — confirm with trial site).
• Your liver enzyme levels or bilirubin (a substance in the blood) are higher than 1.5 times the accepted normal range at screening or just before the study starts.
• Your kidneys are not filtering blood well enough, based on a specific calculation used to measure kidney function (confirm with trial site).
• You have abnormal heart rhythm readings on an ECG, or your blood pressure or heart rate falls outside acceptable ranges at screening or just before the study starts.
• You have a history of a significantly slow heart rate or certain heart rhythm conduction problems (confirm with trial site).
• You have a history of significant asthma (unless it was a childhood condition that has completely gone away) or chronic obstructive pulmonary disease (COPD).
• You have had an alcohol problem in the past year, or you regularly drink more than 14 units of alcohol per week in the past 6 months.
• You have used recreational drugs in the past month (or codeine in the past 3 months), or have had a drug abuse problem in the past year.
• You have donated plasma in the last 7 days, or donated or lost 500 mL or more of blood in the last 30 days before the study drug is given.
• You regularly consume high amounts of caffeine — equivalent to more than 3 regular cups of coffee or 2 energy drinks per day.
• The study doctor believes there is any other reason that would make it unsuitable or unsafe for you to take part.

Important: Always verify eligibility with the trial site directly before applying.