title: Clinical response, drug survival and predictors thereof in 432 ankylosing spondylitis patients after switching tumour necrosis factor α inhibitor therapy: results from the Danish nationwide DANBIO registry.
abstract: OBJECTIVE
  To investigate frequencies and reasons for switching, treatment responses and drug survival in patients with ankylosing spondylitis (AS) switching tumour-necrosis-factor-α inhibitor (TNFi) treatment in routine clinical care.
  
  
  METHODS
  AS patients were identified in the Danish nationwide DANBIO registry. Disease activity, treatment responses (50% or 20 mm reduction in Bath AS Disease Activity Index (BASDAI)), duration and rates of drug survival and predictors thereof were studied in patients receiving ≥2 different biological drugs.
  
  
  RESULTS
  Of 1436 AS patients starting TNFi treatment, 432 patients (30%) switched to a second and 137 (10%) to a third biological drug. Compared with non-switchers, switchers were more frequently women (33%/22%), had shorter disease duration (3 years/5 years) and higher BASDAI (62(52-76) mm/56(43-69) mm (median(interquartile-range))), Bath AS Functional Index (BASFI) (54(39-71) mm/47(31-65) mm) and visual-analogue-scale (VAS) global, pain and fatigue scores when they started the first TNFi (all p<0.01). Main reason for switching was lack of response (56%). During the first, second and third treatment BAS- and VAS scores had decreased after 6 months' treatment (all p<0.05). Median drug survivals were 3.1, 1.6 and 1.8 years respectively (p<0.001). After 2 years of treatment 52% of switchers and 63% of non-switchers had achieved response (number needed to treat 1.9 and 1.6, respectively, p=0.01). Drug survivals were similar regardless of the reason for switching. Male gender and low BASFI predicted drug survival of the second TNFi.
  
  
  CONCLUSIONS
  Nearly one-third of AS patients in clinical practice switched biological treatment. Response rates and drug survivals were lower among switchers, however, half of switchers achieved treatment response.
authors.affiliation: Department of Rheumatology, Gentofte University Hospital, Copenhagen, Denmark. glintborg@dadlnet.dk
authors.forename: Bente
authors.initials: B
authors.lastname: Glintborg
authors.forename: Mikkel
authors.initials: M
authors.lastname: Østergaard
authors.forename: Niels Steen
authors.initials: NS
authors.lastname: Krogh
authors.forename: Ulrik
authors.initials: U
authors.lastname: Tarp
authors.forename: Natalia
authors.initials: N
authors.lastname: Manilo
authors.forename: Anne Gitte Rasmussen
authors.initials: AG
authors.lastname: Loft
authors.forename: Annette
authors.initials: A
authors.lastname: Hansen
authors.forename: Annette
authors.initials: A
authors.lastname: Schlemmer
authors.forename: Victoria
authors.initials: V
authors.lastname: Fana
authors.forename: Hanne M
authors.initials: HM
authors.lastname: Lindegaard
authors.forename: Henrik
authors.initials: H
authors.lastname: Nordin
authors.forename: Claus
authors.initials: C
authors.lastname: Rasmussen
authors.forename: Leif
authors.initials: L
authors.lastname: Ejstrup
authors.forename: Dorte Vendelbo
authors.initials: DV
authors.lastname: Jensen
authors.forename: Peter Mosborg
authors.initials: PM
authors.lastname: Petersen
authors.forename: Merete Lund
authors.initials: ML
authors.lastname: Hetland
mesh_terms: D000068879:Adalimumab; D000328:Adult; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D018501:Antirheumatic Agents / Q000627:therapeutic use*; D003718:Denmark; D057915:Drug Substitution / Q000706:statistics & numerical data*; D000068800:Etanercept; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000627:therapeutic use; D000069285:Infliximab; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D018124:Receptors, Tumor Necrosis Factor / Q000627:therapeutic use; D012042:Registries; D013167:Spondylitis, Ankylosing / Q000188:drug therapy*; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*; D016903:Drug Monitoring
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; C529000:golimumab; D000069285:Infliximab; D000068879:Adalimumab; D000068800:Etanercept