A Phase 4 interventional study of Tecovirimat Oral Capsule and Placebo in Monkeypox, sponsored by Miquel Ekkelenkamp. Recruiting at 12 sites in 8 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-03-28.
Sponsored by Miquel Ekkelenkamp · Phase 4, Interventional, and Treatment
The goal of this randomized controlled double-blind clinical trial is to test the drug tecovirimat in patients with mpox (previously known as monkeypox) disease.
The main questions it aims to answer are:
Participants will receive either the drug tecovirimat orally, 600 mg twice per day, or a matching placebo. The outcome of the infection and the side effect experienced will be compared between the two groups.
This is the only study on the registry with Miquel Ekkelenkamp as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Exclusion Criteria:
Oral treatment with tecovirimat 200 mg capsules. Twice daily three capsules orally. Duration of treatment: 14 days (28 administrations).
Drug: Tecovirimat Oral Capsule
Matching placebo to tecovirimat capsules. Twice daily three capsules orally. Duration of treatment: 14 days (28 administrations).
Drug: Placebo
600 mg, twice daily, 14 days.
Also known as: Tpoxx Tecovirimat
3 capsules, twice daily, 14 days.
Also known as: Oral placebo capsule
Time to complete mpox lesion resolution
Time in days until day 28 after randomization, until the first day on which all lesions are completely healed with a new fresh layer of skin.
Time frame: 28 days
Time to active lesion resolution
The first day on which all skin lesions are scabbed or desquamated (and mucosal lesions healed), counted from start of therapy, with follow-up up to 28 days after randomisation
Time frame: 28 days
Status of the lesions on day 7, 14 and 28
Status of the lesions on day 7, 14, 21 and 28 according to an ordinal scale. The ordinal scale is a) all lesions completely resolved (all scabs dropped off and intact skin remains underneath, and all mucosal lesions healed), b) active lesions resolved (all skin lesions scabbed or desquamated, but not fully resolved), c) active lesions persist but no new lesions in last 24 hours, d) new lesion(s) in last 24 hours.
Time frame: Day 7, day 14 and day 28
Time to resolution of symptoms
Time to resolution of symptoms. Symptoms are counted from start of therapy and assessed by self-assessment. These include fatigue, malaise, nausea, vomiting, abdominal pain, anorexia, cough, dysphagia, odynophagia, fever, headache, oral pain, pain with urination, rectal/anal pain. Signs will be evaluated at study visits only, including lymphadenopathy and proctitis, and are not included in the evaluation of symptoms.
Time frame: 90 days
Occurrence of a negative monkeypox PCR of skin or mucosal swab
Negative monkeypox PCR (Polymerase Chain Reaction) of skin or mucosal swab, assessed for the two most active skin lesions or for the mucosal lesion.
Time frame: Days 7, 14 and 28
Persistence of scars and skin discoloration
Assessment of scars and/or skin discoloration of mpox lesions.
Time frame: Assessed on day 90
Change from baseline in quality of life
Change from baseline of quality of life, assessed by the Dermatology Life Quality Index (DLQI). Minimum value = 0, maximum value = 30, a higher score indicates a worse outcome. (Ten questions with each a minimum of 0 and a maximum of 3.)
Time frame: Assessed on day 14 and day 90.
All-cause mortality
All-cause mortality
Time frame: Assessed on day 28 and on day 90
Time to complication or all-cause admission to hospital or all-cause death
Time to complication or all-cause admission to hospital or all-cause death, within 28 days and within 90 days, applicable to outpatients only, and counted from start of therapy. A complication includes genitourinary complications (e.g. urinary retention, paraphimosis), lower respiratory tract complication (e.g. pneumonia and need for oxygen), ocular impairment (e.g. keratitis), neurologic impairment (e.g. encephalitis) or mental health disturbance (e.g. confusion), cardiac impairment (e.g. cardiomyopathy or myocarditis), severe dehydration needing admission, secondary bacterial skin infection or severe pain needing hospital admission.
Time frame: Assessed within 28 days and within 90 days.
Frequency of AEs, SAEs and SUSARs
Frequency of Adverse Events (AEs), Serious Adverse Events (SAEs) and Suspected Unexpected Serious Adverse Reaction (SUSARs) for the specific therapeutic, within the first 28 days, but also assessed during the total follow-up (up to day 90).
Time frame: Assessed within 28 days and within 90 days.
Resolution of pain
Resolution of pain, by measuring: 1. time to resolution of pain assessed by the Numeric Rating Scale (NRS) for pain, 2. time to cessation of the use of analgesic medication, defined as time to consistently reporting no use of analgesia for mpox-related lesions, up to 90 days after randomisation. 3. anal pain on days 7, 14, and 90 assessed by the Health Related Symptom Index.
Time frame: Assessed on days 7, 14 and 90.
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Mpox (monkeypox)