title: Tumour necrosis factor (TNF)alpha -308 G/G promoter polymorphism and TNFalpha levels correlate with a better response to adalimumab in patients with rheumatoid arthritis.
abstract: OBJECTIVE
  To investigate the influence of -308 tumour necrosis factor-alpha (TNFalpha) promoter polymorphism and circulating TNFalpha levels in the clinical response to adalimumab treatment in patients with rheumatoid arthritis (RA).
  
  
  METHODS
  Eighty-one patients with active RA were genotyped for the -308 TNFalpha polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis and subdivided into two groups for each polymorphism (G/A and G/G genotype). All received 40 mg of adalimumab subcutaneously every other week. We compared the groups' clinical responses to adalimumab at 8, 16, and 24 weeks using the Disease Activity Score in 28 joints (DAS28).
  
  
  RESULTS
  Both groups showed a significant improvement from baseline. A significant difference between groups was found at week 24. We found that 88.2% of G/G versus 68.4% of G/A for the -308 polymorphism were DAS28 responders (p = 0.05). The score improvement at week 24 was 2.5 +/- 1.3 in the G/G group and 1.8 +/- 1.3 in the G/A group for the -308 polymorphism (p = 0.04). The median of serum TNFalpha levels of the G/A group were lower than those of the G/G group, and statistically different at weeks 8 and 24 (p < 0.039 and p < 0.043). When comparing baseline levels to those achieved at 8, 16, and 24 weeks for the whole group, only responder patients showed a statistically significant overall increase in TNFalpha over time (p < 0.000001).
  
  
  CONCLUSIONS
  A relationship between DAS28 improvement, the -308 G/G polymorphism, and increased circulating TNFalpha levels was found in Chilean RA patients treated with adalimumab.
authors.affiliation: Rheumatology Section, Department of Medicine, Clinical Hospital University of Chile, Santiago. mcuchaco@yahoo.com
authors.forename: M
authors.initials: M
authors.lastname: Cuchacovich
authors.forename: L
authors.initials: L
authors.lastname: Soto
authors.forename: M
authors.initials: M
authors.lastname: Edwardes
authors.forename: M
authors.initials: M
authors.lastname: Gutierrez
authors.forename: C
authors.initials: C
authors.lastname: Llanos
authors.forename: D
authors.initials: D
authors.lastname: Pacheco
authors.forename: F
authors.initials: F
authors.lastname: Sabugo
authors.forename: M
authors.initials: M
authors.lastname: Alamo
authors.forename: C
authors.initials: C
authors.lastname: Fuentealba
authors.forename: L
authors.initials: L
authors.lastname: Villanueva
authors.forename: H
authors.initials: H
authors.lastname: Gatica
authors.forename: I
authors.initials: I
authors.lastname: Schiattino
authors.forename: L
authors.initials: L
authors.lastname: Salazaro
authors.forename: D
authors.initials: D
authors.lastname: Catalan
authors.forename: O
authors.initials: O
authors.lastname: Valenzuela
authors.forename: F
authors.initials: F
authors.lastname: Salazar-Onfray
authors.forename: J C
authors.initials: JC
authors.lastname: Aguillón
mesh_terms: D000068879:Adalimumab; D000328:Adult; D000911:Antibodies, Monoclonal / Q000009:adverse effects / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000188:drug therapy*; D002677:Chile; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D013997:Time Factors; D016896:Treatment Outcome; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors / Q000097:blood / Q000235:genetics*
chemical_list: D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D018501:Antirheumatic Agents; D014409:Tumor Necrosis Factor-alpha; D000068879:Adalimumab