A Trial to Assess the Safety, Tolerability, and Pharmacokinetics of the Anti-Orthopoxvirus Compound Tecovirimat

Inclusion Criteria: * 18 to 80 years old, inclusive * Available for clinical follow-up for the duration of the study * Able and willing to give informed consent * In good general health without clinically significant medical history; not have been hospitalized for a chronic medical condition for the last 2 years * Able to comply with dietary requirements throughout the study drug dosing period * Adequate venous access for those individuals participating in PK testing * PE and laboratory results without clinically significant findings within the 14 days before receipt of study drug * Agree not to drink alcohol from the beginning of the Screening Period through the completion of the Day 28 Follow up Visit * Agree not to use any nicotine products, including electronic vapor cigarettes, nicotine patches or nicotine gum for at least 30 days before the Day 1 Visit and through completion of the Day 15 Dosing complete Visit * Agree not to consume caffeine during all study visits, including overnight stays if participating in PK subset * Agree not to receive any immunizations/vaccinations * Agree not to take herbal products * Able and willing to refrain from taking any prescriptions and nonprescription medications with exceptions * For women of childbearing potential, negative serum and urine pregnancy testing * If male, agree not to donate sperm * Meet 1 of the following criteria: The subject or their partner has undergone surgical sterilization; the subject is postmenopausal; the subject agrees to be abstinent; the subject agrees to consistently use a method of approved birth control. Exclusion Criteria: * Pregnant or breast-feeding or planning pregnancy * Have a history of any clinically significant conditions * Have any limitation of activity related to cardiac disease * Have a bleeding disorder diagnosed by a doctor, or a history of significant bruising or bleeding with intramuscular injections or blood draws * Currently using certain medications * Have a malignancy that is active or a treated malignancy for which there is no reasonable assurance of sustained cure, or malignancy that is likely to recur during the study * Have a history of seizure * Have a clinically significant blood dyscrasia * Have a history of drug allergy that contraindicates participation in the trial * Have a medical, psychiatric, or social condition or any occupational reason, or other responsibility that in the judgment of the investigator would render the subject unable to comply with the protocol * Have an inability to swallow medication * Have a clinically significant abnormal ECG * Have participated in a clinical trials within 30 days of study entry or planning to participate in any experimental treatment study during the study period * Have a history or current drug or alcohol abuse * Have received immunizations/vaccines * Have a current clinically significant acute bacterial, fungal, or mycobacterial infection requiring administration of systemic antibiotics * Have known chronic bacterial, mycobacterial, fungal, parasitic, or protozoal infection with the exception of clinically significant dermal infections * Have known hepatitis B or C infection, or positive test result * Have known HIV infection or AIDS or a positive test for HIV * Have a current clinically significant viral infection * Have known clinically significant chronic viral infection * have received treatment with greater than 20 mg prednisone or equivalent dose or any immunosuppressant or immunomodulary medication * Have abnormal laboratory testing during screening * Have a greater than or equal than 20% risk of suffering a major cardiovascular event * Have been previously enrolled in this or any clinical trial involving tecovirimat