title: Head-to-head comparison of udenafil vs amlodipine in the treatment of secondary Raynaud's phenomenon: a double-blind, randomized, cross-over study.
abstract: OBJECTIVE
  RP is a reversible vasoconstriction of digital arteries that causes pain and skin discoloration. This study compared the efficacy of the new phosphodiesterase type 5 inhibitor udenafil with that of the calcium channel blocker amlodipine in the treatment of secondary RP.
  
  
  METHODS
  A total of 29 patients with secondary RP associated with connective tissue diseases were enrolled in this double-blind, randomized, cross-over study. The patients were randomized to receive udenafil 100 mg/day or amlodipine 10 mg/day for 4 weeks. After a washout period they were crossed over to the other drug for another 4 weeks. The primary outcome was RP frequency before and after treatment. The secondary outcomes were RP condition scores, RP duration, number of digital ulcers, HAQ, physician global assessment and digital artery flow before and after treatment.
  
  
  RESULTS
  Amlodipine and udenafil both decreased the rate of RP attack significantly. The drugs did not differ in terms of RP frequency or any of the secondary outcomes except for digital blood flow; udenafil improved it significantly better than amlodipine (P = 0.021). Udenafil was well tolerated without serious adverse effects.
  
  
  CONCLUSIONS
  Udenafil and amlodipine have comparable efficacy in improving RP attacks. In addition, udenafil improves the blood flow in digital arteries compared with amlodipine.
  
  
  BACKGROUND
  www.clinicaltrials.gov, protocol number NCT01280266.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, 28 Yongon-dong, Chongno-gu, Seoul 110-744, Korea. leb7616@snu.ac.kr.
authors.forename: Eun Young
authors.initials: EY
authors.lastname: Lee
authors.forename: Jin Kyun
authors.initials: JK
authors.lastname: Park
authors.forename: Whal
authors.initials: W
authors.lastname: Lee
authors.forename: Yeo Koon
authors.initials: YK
authors.lastname: Kim
authors.forename: Claire Su-Yeon
authors.initials: CS
authors.lastname: Park
authors.forename: Jon T
authors.initials: JT
authors.lastname: Giles
authors.forename: Jun Won
authors.initials: JW
authors.lastname: Park
authors.forename: Kichul
authors.initials: K
authors.lastname: Shin
authors.forename: Jeong Seok
authors.initials: JS
authors.lastname: Lee
authors.forename: Yeong Wook
authors.initials: YW
authors.lastname: Song
authors.forename: Eun Bong
authors.initials: EB
authors.lastname: Lee
mesh_terms: D000328:Adult; D017311:Amlodipine / Q000627:therapeutic use*; D003240:Connective Tissue Diseases / Q000150:complications; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005260:Female; D005385:Fingers / Q000098:blood supply*; D006801:Humans; D008297:Male; D008875:Middle Aged; D058986:Phosphodiesterase 5 Inhibitors / Q000627:therapeutic use*; D011743:Pyrimidines / Q000627:therapeutic use*; D011928:Raynaud Disease / Q000188:drug therapy* / Q000209:etiology; D013449:Sulfonamides / Q000627:therapeutic use*; D016896:Treatment Outcome; D014665:Vasodilator Agents / Q000627:therapeutic use*; D000096926:Benzenesulfonamides
chemical_list: D017311:Amlodipine; D058986:Phosphodiesterase 5 Inhibitors; D011743:Pyrimidines; D013449:Sulfonamides; D014665:Vasodilator Agents; C419664:udenafil; D000096926:Benzenesulfonamides
keywords: Raynaud’s phenomenon; amlodipine; digital blood flow; udenafil; vasodilator