Smallpox drug put to the test in healthy volunteers
NCT ID NCT02474589
First seen Sep 11, 2026 ยท Last updated Sep 11, 2026
Summary
Researchers are testing an antiviral drug called tecovirimat to see if it is safe and well tolerated when taken by mouth for 14 days. The trial enrolls healthy adults aged 18 to 80 and compares tecovirimat with a placebo. The goal is to gather safety information that could support the drug as a defense against smallpox.
What this could mean
Our plain-language read of the trial. This is informational only, not medical advice or a prediction.
- Active substance
- tecovirimat, an antiviral drug
- What this could lead to
- If it works, this could support tecovirimat as a stockpiled medicine to protect people exposed to smallpox.
- What could go wrong
- The trial only measures safety and drug levels in healthy volunteers, so it cannot prove the drug prevents or treats smallpox. Side effects may emerge, and animal-rule approval does not guarantee real-world protection.
This is an AI summary of the original study and may miss details. Read our disclaimer.
Study facts
What this study's own registry entry says, in plain language.
- Phase
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Phase 3
Large-scale testing in a bigger group. Usually the last step before a treatment can be approved.
- Participants
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449 people
The number who actually took part.
- Started
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Jun 2015
- Finished
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Aug 2016
- Lead sponsor
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A company
The lead sponsor is a pharmaceutical, biotech, or medical-device company.
Who can take part
This study's own entry requirements. Only the study team can say for certain whether you qualify.
- Ages
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18 to 80 years
- Sex
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Anyone
- Healthy volunteers
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Accepted
You do not need to have the condition being studied to take part.
Show the full entry requirements Hide the full entry requirements
Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.
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
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Conditions
The condition(s) this trial relates to.
As listed by the trial registrant
The condition terms exactly as the trial's registrant entered them.
Contacts and locations
Locations
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Benchmark Research
Austin, Texas, 78705, United States
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Benchmark Research
Fort Worth, Texas, 76135, United States
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Center for Pharmaceutical Research
Kansas City, Missouri, 64114, United States
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Coastal Clinical Research, Inc.
Mobile, Alabama, 36608, United States
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Heartland Research Associates, LLC
Newton, Kansas, 67114, United States
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Johnson County Clinical Trials
Lenexa, Kansas, 66219, United States
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Medical Research South
Charleston, South Carolina, 29407, United States
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Meridien Clinical Research
Omaha, Nebraska, 68134, United States
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Paradigm Research
Redding, California, 96001, United States
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Paradigm Research
San Diego, California, 92117, United States
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Sundance Clinical Research LLC
St Louis, Missouri, 63141, United States
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