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

Multicenter, double-blind, placebo controlled, Phase 3 study to determine the safety and tolerability of oral tecovirimat, an anti orthopoxvirus compound, in subjects.

Pharmacokinetics and safety and tolerability data will be collected.

Eligibility Criteria:
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