[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"health-study-detail:100625314":3},{"organization":4,"armGroups":7,"interventions":14,"overallOfficials":19,"centralContacts":20,"locations":26,"responsibleParty":42,"collaborators":46,"id":53,"slug":19,"hasResults":54,"nctId":55,"briefTitle":56,"officialTitle":57,"acronym":58,"eligibilityCriteria":59,"healthyVolunteers":60,"sex":61,"minAge":62,"maxAge":63,"enrollmentInfo":64,"targetDuration":19,"studyType":67,"phases":68,"briefSummary":70,"conditions":71,"keywords":73,"overallStatus":79,"whyStopped":19,"lastUpdateSubmitDate":80,"lastUpdatePostDateStruct":81,"startDateStruct":84,"completionDateStruct":86,"leadSponsor":88,"locationsCount":89},{"fullName":5,"class":6},"University of Copenhagen","OTHER",[8],{"label":9,"type":10,"description":11,"interventionNames":12},"ATR-258","EXPERIMENTAL","Daily oral ATR-258",[13],"Drug: ATR-258",[15],{"type":16,"name":9,"description":17,"armGroupLabels":18,"otherNames":19},"DRUG","Daily oral ATR-258 for 8 weeks with repeated experimental assessment days (Days 1, 15, 29, 56).",[9],null,[21],{"name":22,"role":23,"phone":24,"phoneExt":19,"email":25},"Morten Hostrup, PhD, MD","CONTACT","+45 24474785","mhostrup@nexs.ku.dk",[27],{"facility":28,"status":19,"city":29,"state":19,"zip":30,"country":31,"countryCode":32,"cosmosGeoPoint":33,"geoPoint":38,"contacts":39},"University of Copenhagen, August Krogh Section for Human & Molecular Physiology","Copenhagen","2100","Denmark","DK",{"type":34,"coordinates":35},"Point",[36,37],12.56553,55.67594,{"lat":37,"lon":36},[40],{"name":41,"role":23,"phone":19,"phoneExt":19,"email":25},"Morten Hostrup",{"type":43,"investigatorFullName":44,"investigatorTitle":45,"investigatorAffiliation":5,"oldNameTitle":19,"oldOrganization":19},"SPONSOR_INVESTIGATOR","Morten Hostrup, PhD","Associate Professor, MD",[47,50,51],{"name":48,"class":49},"Atrogi AB","INDUSTRY",{"name":5,"class":6},{"name":52,"class":6},"Stockholm University","100625314",false,"NCT07421024","Biased GRK Signaling Via β2-Adrenergic Receptors in Human Skeletal Muscle","Biased G Protein-Coupled Receptor Kinase Signaling Via β2-Adrenergic Receptors and Downstream Activation of Protein Synthesis-Regulating Kinases and Receptor Desensitization in Human Skeletal Muscle","ATR","Inclusion Criteria:\n\n* Healthy men\n* Age 21-45 years\n* BMI 25-35 kg\u002Fm\\^2\n* Body fat percentage 25-40%\n* Lean Mass Index 14-22\n\nExclusion Criteria:\n\n* Regular use of or allergy to β2-agonists\n* Serious adverse reactions to β2-agonists\n* Current smoker\n* Regular use of medication (except OTC allergy or analgesics)\n* Abnormal ECG before or after β2-AR stimulation\n* Hypertension\n* Reduced kidney function (eGFR \\\u003C 90 ml\u002Fmin\u002F1.73m\\^2)\n* Cardiovascular, metabolic, gastrointestinal, renal, or pulmonary disease\n* Psychiatric or neurological disorders affecting compliance\u002Fsafety reporting\n* Cancer history within the last 5 years\n* Substance abuse or alcohol intake \\>14 units\u002Fweek",true,"MALE","21 Years","45 Years",{"count":65,"type":66},10,"ESTIMATED","INTERVENTIONAL",[69],"PHASE2","This longitudinal mechanistic physiological study examines biased β2-adrenergic receptor (β2-AR) signaling in human skeletal muscle, with emphasis on G protein-coupled receptor kinase (GRK)-mediated pathways. Participants will receive daily oral dosing of the GRK-selective long-acting β2-agonist ATR-258 for 8 weeks. Muscle biopsies and physiological measurements will quantify GRK-, cAMP\u002FPKA-, and β-arrestin-related signaling, fiber-type specificity, and potential receptor desensitization with repeated stimulation.",[72],"Overweight and Obesity",[74,75,76,77,78],"beta2","muscle","atr-258","adrenergic","biased signaling","NOT_YET_RECRUITING","2026-02-16",{"date":82,"type":83},"2026-02-19","ACTUAL",{"date":85,"type":66},"2026-02-20",{"date":87,"type":66},"2026-12-31",{"name":44,"class":6},1]