Corticosteroids for loss of smell by COVID-19 infection – COCOS trial

COrticosteroids for COVID-19 induced loss of Smell – COCOS trial - COCOS trail

Status

Active, not recruiting

Phases

Phase 4

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2021-004021-71-NL

Enrollment

116

Registered

2021-10-12

Start date

2021-10-13

Completion date

Unknown

Last updated

2023-07-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Loss of smell after COVID-19 infection, persisting after 4 weeks

Interventions

Product Name: Prednisolon Pharmaceutical Form: Capsule Pharmaceutical form of the placebo: Capsule Route of administration of the placebo: Oral use

Eligibility

Sex/Gender

All

Inclusion criteria

Inclusion criteria: • Recent COVID-19 infection (=65 years) yes F.1.3.1 Number of subjects for this age range 26

Exclusion criteria

Exclusion criteria: • Pre-existing olfactory disorders • Chronic rhinitis or rhinosinusitis (with or without nasal polyps) • Corticosteroids (nasal, oral or intravenously) since positive test • Pregnancy • Contra-indications of steroid use (Insulin dependent diabetes mellitus, Ulcus pepticum)

Design outcomes

Primary

Measure	Time frame
Main Objective: To determine the efficacy of a short high-dose treatment of oral prednisolone for persistent loss of smell after COVID-19 infection. ;Secondary Objective: not applicable ;Primary end point(s): Objective olfactory function bij means of Sniffin’Sticks, combining olfactory detection threshold (T), discrimination (D) and identification (I) ability into a composite TDI score (ranging from 1-48 points) that can be categorized into normosmia, hyposmia and anosmia . Clinical improvement is set at >5.5 points;Timepoint(s) of evaluation of this end point: 12 weeks	—

Measure

Time frame

Main Objective: To determine the efficacy of a short high-dose treatment of oral prednisolone for persistent loss of smell after COVID-19 infection. ;Secondary Objective: not applicable ;Primary end point(s): Objective olfactory function bij means of Sniffin’Sticks, combining olfactory detection threshold (T), discrimination (D) and identification (I) ability into a composite TDI score (ranging from 1-48 points) that can be categorized into normosmia, hyposmia and anosmia . Clinical improvement is set at >5.5 points;Timepoint(s) of evaluation of this end point: 12 weeks

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Secondary

Measure	Time frame
Secondary end point(s): • Objective gustatory function by means of Taste Strips, assessing recognition thresholds and identification for the four basis tastes (possible score range 0-16) . Clinical improvement is set at > 2 points. • Self-reported smell, taste, parosmia, trigeminal sensations by means of VAS ratings (parma). Recovery is considered an improvement of at least 80% of their pre-illness function • Quality of life, as measured by the Questionnaire of Olfactory disorders, an appropriate and valid measure of the impact of olfactory dysfunction on daily life ;Timepoint(s) of evaluation of this end point: 12 weeks	—

Measure

Time frame

Secondary end point(s): • Objective gustatory function by means of Taste Strips, assessing recognition thresholds and identification for the four basis tastes (possible score range 0-16) . Clinical improvement is set at > 2 points. • Self-reported smell, taste, parosmia, trigeminal sensations by means of VAS ratings (parma). Recovery is considered an improvement of at least 80% of their pre-illness function • Quality of life, as measured by the Questionnaire of Olfactory disorders, an appropriate and valid measure of the impact of olfactory dysfunction on daily life ;Timepoint(s) of evaluation of this end point: 12 weeks

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Countries

Netherlands

Contacts

Public ContactOtorhinolaryngology department

University Medical Center Utrecht

+310887555555

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 11, 2026