NCT05467683

CO2 Reactivity as a Biomarker of Non-Response to Exposure-Based Therapy

Recruiting now NA Last updated 19 February 2026

What this trial tests

NA trial testing Exposure-Based Therapy in Obsessive-Compulsive Disorder in 600 participants. Currently enrolling.

Timeline

2 November 2022

Primary endpoint
1 December 2026

28 February 2027

Quick facts

Lead sponsor	University of Texas at Austin
Phase	NA
Status	Recruiting now
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	treatment
Enrollment	600
Start date	2 November 2022
Primary completion	1 December 2026
Estimated completion	28 February 2027
Sites	2 locations across United States

Drugs / interventions tested

• Exposure-Based Therapy

Conditions studied

• Obsessive-Compulsive Disorder — all drugs for Obsessive-Compulsive Disorder →
• Post Traumatic Stress Disorder — all drugs for Post Traumatic Stress Disorder →
• Generalized Anxiety Disorder — all drugs for Generalized Anxiety Disorder →
• Social Anxiety Disorder — all drugs for Social Anxiety Disorder →

Sponsor

University of Texas at Austin

Who can join

Adults 18 to 70, any sex, with Obsessive-Compulsive Disorder or Post Traumatic Stress Disorder. Patients with the condition only — healthy volunteers not accepted.

Sponsor's own description

Anxiety-, obsessive-compulsive and trauma- and stressor-related disorders reflect a significant public health problem. This study is designed to evaluate the predictive power of a novel biomarker based on a CO2 challenge, thus addressing the central question "can this easy-to-administer assay aid clinicians in deciding whether or not to initiate exposure-based therapy?"

Publications & conference data

3 peer-reviewed publications reference this trial (live from Europe PMC):

1. CO₂ reactivity as a biomarker of exposure-based therapy non-response: study protocol.
   Smits JAJ, Monfils MH, Otto MW, Telch MJ, et al · · 2022 · cited 6× · PMID 36575425 · DOI 10.1186/s12888-022-04478-x
2. Hereditary Patterns and Genetic Associations in Obsessive-Compulsive Disorder (OCD): Neuropsychiatric Insights, Genetic Influences, and Treatment Perspectives.
   Dhiman A, Mehan S, Khan Z, Tiwari A, et al · · 2025 · cited 4× · PMID 39219434 · DOI 10.2174/0115665232316708240828063527
3. CO2 Reactivity as a Biomarker of Exposure-based Therapy Non-Response: Study Protocol
   Smits JAJ, Monfils M, Otto MW, Telch MJ, et al · · 2022 · DOI 10.21203/rs.3.rs-2298817/v1