Rolf Arne Klaasen

  • Researcher; MSci Pharm
 

Publications 2024

Brun MK, Gehin JE, Bjørlykke KH, Warren DJ, Klaasen RA, Sexton J, Sandanger Ø, Kvien TK, Mørk C, Jahnsen J, Bolstad N, Jørgensen KK, Haavardsholm EA, Goll GL, Syversen SW (2024)
Clinical consequences of infliximab immunogenicity and the effect of proactive therapeutic drug monitoring: exploratory analyses of the randomised, controlled NOR-DRUM trials
Lancet Rheumatol, 6 (4), e226-e236
DOI 10.1016/S2665-9913(23)00341-7, PubMed 38402891

Gehin JE, Klaasen RA, Klami Kristianslund E, Jyssum I, Sexton J, Warren DJ, Aletaha D, Haavardsholm EA, Syversen SW, Goll GL, Bolstad N (2024)
Therapeutic serum level for adalimumab in rheumatoid arthritis: explorative analyses of data from a randomised phase III trial
RMD Open, 10 (4)
DOI 10.1136/rmdopen-2024-004888, PubMed 39537558

Lukina P, Andersen IL, Eggen PT, Mjønes PG, Rønne E, Bolstad N, Klaasen RA, Warren DJ, Iversen R, Hveem K, Bernklev T, Jelsness-Jørgensen LP, Pedersen L, Jonkers I, Lagergren P, Sollid LM, Lundin K, Ness-Jensen E (2024)
Coeliac disease in the Trøndelag Health Study (HUNT), Norway, a population-based cohort of coeliac disease patients
BMJ Open, 14 (1), e077131
DOI 10.1136/bmjopen-2023-077131, PubMed 38195172

Lukina P, Andersen IL, Klaasen RA, Warren DJ, Bolstad N, Mjønes P, Rønne E, Iversen R, Sollid LM, Lundin KEA, Ness-Jensen E (2024)
The Prevalence and Rate of Undiagnosed Celiac Disease in an Adult General Population, the Trøndelag Health Study, Norway
Clin Gastroenterol Hepatol (in press)
DOI 10.1016/j.cgh.2024.06.027, PubMed 38987013

Ovesen PD, Attauabi M, Ilvemark JFKF, Wewer MD, Warren DJ, Burisch J, Klaasen RA, Bolstad N, Steenholdt C, Seidelin JB (2024)
Effects of prednisolone tapering on effectiveness of infliximab in patients with ulcerative colitis: data from a retrospective cohort
BMJ Open Gastroenterol, 11 (1)
DOI 10.1136/bmjgast-2024-001343, PubMed 38719549

Steenholdt C, Lorentsen RD, Petersen PN, Widigson ES, Kloft C, Klaasen RA, Brynskov J (2024)
Therapeutic drug monitoring of vedolizumab therapy in inflammatory bowel disease
J Gastroenterol Hepatol, 39 (6), 1088-1098
DOI 10.1111/jgh.16518, PubMed 38380724

Publications 2023

Brun MK, Bjørlykke KH, Viken MK, Stenvik GE, Klaasen RA, Gehin JE, Warren DJ, Sexton J, Sandanger Ø, Kvien TK, Mørk C, Haavardsholm EA, Jahnsen J, Goll GL, Lie BA, Bolstad N, Jørgensen KK, Syversen SW (2023)
HLA-DQ2 is associated with anti-drug antibody formation to infliximab in patients with immune-mediated inflammatory diseases
J Intern Med, 293 (5), 648-655
DOI 10.1111/joim.13616, PubMed 36843323

Publications 2022

Brun MK, Goll GL, Jørgensen KK, Sexton J, Gehin JE, Sandanger Ø, Olsen IC, Klaasen RA, Warren DJ, Mørk C, Kvien TK, Jahnsen J, Bolstad N, Haavardsholm EA, Syversen SW (2022)
Risk factors for anti-drug antibody formation to infliximab: Secondary analyses of a randomised controlled trial
J Intern Med, 292 (3), 477-491
DOI 10.1111/joim.13495, PubMed 35411981

Klaasen RA, Warren DJ, Iversen R, Bolstad N, Andersen IL, Mjønes P, Rønne E, Lundin KEA, Sollid LM, Ness-Jensen E (2022)
The development and validation of a high-capacity serological assay for celiac disease
Clin Biochem, 107, 13-18
DOI 10.1016/j.clinbiochem.2022.05.010, PubMed 35660483

Publications 2021

Gehin JE, Klaasen RA, Norli ES, Warren DJ, Syversen SW, Goll GL, Bjøro T, Kvien TK, Mjaavatten MD, Bolstad N (2021)
Rheumatoid factor and falsely elevated results in commercial immunoassays: data from an early arthritis cohort
Rheumatol Int, 41 (9), 1657-1665
DOI 10.1007/s00296-021-04865-9, PubMed 33944985

Syversen SW, Goll GL, Jørgensen KK, Sandanger Ø, Sexton J, Olsen IC, Gehin JE, Warren DJ, Brun MK, Klaasen RA, Karlsen LN, Noraberg G, Zettel C, Ljoså MKA, Haugen AJ, Njålla RJ, Bruun TJ, Seeberg KA, Michelsen B, Strand EK, Skorpe S, Blomgren IM, Bragnes YH, Dotterud CK, Thune T et al. (2021)
Effect of Therapeutic Drug Monitoring vs Standard Therapy During Infliximab Induction on Disease Remission in Patients With Chronic Immune-Mediated Inflammatory Diseases: A Randomized Clinical Trial
JAMA, 325 (17), 1744-1754
DOI 10.1001/jama.2021.4172, PubMed 33944876

Syversen SW, Jørgensen KK, Goll GL, Brun MK, Sandanger Ø, Bjørlykke KH, Sexton J, Olsen IC, Gehin JE, Warren DJ, Klaasen RA, Noraberg G, Bruun TJ, Dotterud CK, Ljoså MKA, Haugen AJ, Njålla RJ, Zettel C, Ystrøm CM, Bragnes YH, Skorpe S, Thune T, Seeberg KA, Michelsen B, Blomgren IM et al. (2021)
Effect of Therapeutic Drug Monitoring vs Standard Therapy During Maintenance Infliximab Therapy on Disease Control in Patients With Immune-Mediated Inflammatory Diseases: A Randomized Clinical Trial
JAMA, 326 (23), 2375-2384
DOI 10.1001/jama.2021.21316, PubMed 34932077

Publications 2020

Gustavsen MT, Midtvedt K, Robertsen I, Woillard JB, Debord J, Klaasen RA, Vethe NT, Bergan S, Åsberg A (2020)
Fasting Status and Circadian Variation Must be Considered When Performing AUC-based Therapeutic Drug Monitoring of Tacrolimus in Renal Transplant Recipients
Clin Transl Sci, 13 (6), 1327-1335
DOI 10.1111/cts.12833, PubMed 32652886

Jørgensen KK, Goll GL, Sexton J, Bolstad N, Olsen IC, Asak Ø, Berset IP, Blomgren IM, Dvergsnes K, Florholmen J, Frigstad SO, Henriksen M, Hagfors J, Huppertz-Hauss G, Haavardsholm EA, Klaasen RA, Moum B, Noraberg G, Prestegård U, Rydning JH, Sagatun L, Seeberg KA, Torp R, Vold C, Warren DJ et al. (2020)
Efficacy and Safety of CT-P13 in Inflammatory Bowel Disease after Switching from Originator Infliximab: Exploratory Analyses from the NOR-SWITCH Main and Extension Trials
BioDrugs, 34 (5), 681-694
DOI 10.1007/s40259-020-00438-7, PubMed 32965617

Klaasen RA, Bergan S, Bremer S, Hole K, Nordahl CB, Andersen AM, Midtvedt K, Skauby MH, Vethe NT (2020)
Pharmacodynamic assessment of mycophenolic acid in resting and activated target cell population during the first year after renal transplantation
Br J Clin Pharmacol, 86 (6), 1100-1112
DOI 10.1111/bcp.14218, PubMed 31925806

Publications 2019

Goll GL, Jørgensen KK, Sexton J, Olsen IC, Bolstad N, Haavardsholm EA, Lundin KEA, Tveit KS, Lorentzen M, Berset IP, Fevang BTS, Kalstad S, Ryggen K, Warren DJ, Klaasen RA, Asak Ø, Baigh S, Blomgren IM, Brenna Ø, Bruun TJ, Dvergsnes K, Frigstad SO, Hansen IM, Hatten ISH, Huppertz-Hauss G et al. (2019)
Long-term efficacy and safety of biosimilar infliximab (CT-P13) after switching from originator infliximab: open-label extension of the NOR-SWITCH trial
J Intern Med, 285 (6), 653-669
DOI 10.1111/joim.12880, PubMed 30762274

Klaasen RA, Egeland EJ, Chan J, Midtvedt K, Svensson M, Bolstad N, Fellström B, Holdaas H, Åsberg A, Bergan S, Vethe NT, Warren DJ (2019)
A Fully Automated Method for the Determination of Serum Belatacept and Its Application in a Pharmacokinetic Investigation in Renal Transplant Recipients
Ther Drug Monit, 41 (1), 11-18
DOI 10.1097/FTD.0000000000000580, PubMed 30633722

Publications 2018

Egeland EJ, Størset E, Robertsen I, Hermann M, Midtvedt K, Gustavsen MT, Klaasen R, Bergan S, Hartmann A, Åsberg A (2018)
The Authors' Reply
Transplantation, 102 (1), e43-e44
DOI 10.1097/TP.0000000000001961, PubMed 28957846

Klaasen RA, Bergan S, Bremer S, Daleq L, Andersen AM, Midtvedt K, Skauby MH, Vethe NT (2018)
Longitudinal Study of Tacrolimus in Lymphocytes During the First Year After Kidney Transplantation
Ther Drug Monit, 40 (5), 558-566
DOI 10.1097/FTD.0000000000000539, PubMed 30086087

Publications 2017

Egeland EJ, Robertsen I, Hermann M, Midtvedt K, Størset E, Gustavsen MT, Reisæter AV, Klaasen R, Bergan S, Holdaas H, Hartmann A, Åsberg A (2017)
High Tacrolimus Clearance Is a Risk Factor for Acute Rejection in the Early Phase After Renal Transplantation
Transplantation, 101 (8), e273-e279
DOI 10.1097/TP.0000000000001796, PubMed 28452920