Efficacy Study of PDE-5 Inhibitor and Calcium Channel Inhibitor for the Treatment of Secondary Raynaud Phenomenon

• Change in Raynaud's Condition Score (RCS) [ Time Frame: baseline and 4 weeks ] [ Designated as safety issue: No ]

  change in the RCS. RCS combines daily activty, frequency, duration and severity as well as impact of RP attack (Measuring disease activity and functional status in patients with scleroderma and Raynaud's phenomenon, Merkel et al,Arthritis Rheum. 2002 Sep;46(9):2410-20).

  Range 0-10 ordinal scale 0..good 10.. bad

• Change in the RP Duration [ Time Frame: baseline and 4 weeks ] [ Designated as safety issue: No ]
  Change in the average RP duration in minutes (min) per attack. 0 -- unlimited
• Change in Health Assessment Questionnaire (HAQ) [ Time Frame: 0 and 4 weeks ] [ Designated as safety issue: No ]
  Ordinal scale 0-10 0 good 10 bad
• Change in Physician's Global Assessment on Visual Analogue Scale (VAS) [ Time Frame: at 0 (baseline) and 4 weeks (after treatment) ] [ Designated as safety issue: No ]

  Physician's global assessment (PGA) on VAS assesses the overall condition of the patient. The scale ranges from 0 - 10, with 0 being good and 10 bad. As such, change in the GPA measures the change in the patient's condition from the baseline.

  negative value (decrease in value) means improvement.

• Change in Digital Ulcer Number [ Time Frame: baseline and 4 weeks ] [ Designated as safety issue: No ]
  0 - unlimited. Number of digital ulcers in all fingers are counted by the investigators and recorded at each visit. The number of ulcers in all fingers indirectly reflect the extent of critical ischemia. As such. the decrease in digital ulcer number reflects positive response to treatment (=better blood flow), whereas the increase ulcer numbers indicates worsening finger ischemia from baseline.
• Change in Peak Systolic Flow (cm/Sec) [ Time Frame: baseline and 4 weeks ] [ Designated as safety issue: No ]

  Change in digital artery flow velocity in proper palmar digital artery in cm/sec.

  0-unlimited

• Time-averaged Peak Velocity (cm/Sec) [ Time Frame: baseline and 4 weeks ] [ Designated as safety issue: No ]
  changes in the averaged blood flow (Time-averaged peak velocity) Blood flow in cm/sec 0 - unlimited.
• Dorsal-digital-difference. [ Time Frame: baseline and 4 weeks ] [ Designated as safety issue: No ]
  The temperature difference between finger tips and dorsum of same hand. range 0 - unlimited in degree celcius.

• change in raynaud's condition score (RCS) [ Time Frame: during 4 weeks ] [ Designated as safety issue: No ]
  change in the RCS during the fourth week of treatment from baseline, comparing active drug to placebo
• change in the total duration of RP/week [ Time Frame: during 4 weeks ] [ Designated as safety issue: No ]
  change in the total duration of RP/week during the fourth week of treatment compared to the total duration of RP/week at baseline
• change in Health Assessment Questionnaire (HAQ) [ Time Frame: 4weeks ] [ Designated as safety issue: No ]
• change in physician's Visual Analog Scale (VAS) [ Time Frame: 4weeks ] [ Designated as safety issue: No ]
• change in patient's VAS [ Time Frame: 4weeks ] [ Designated as safety issue: No ]
• prevalence of digital ulcer comparing Udenafil to Calcium Channel Blocker (CCB) [ Time Frame: 4weeks ] [ Designated as safety issue: No ]
• Improvement of digital ulcer comparing Udenafil to CCB [ Time Frame: 4 weeks ] [ Designated as safety issue: No ]
• remission of digital ulcer comparing Udenafil to CCB [ Time Frame: 4 weeks ] [ Designated as safety issue: No ]
• change in nailfold capillary microscopy finding [ Time Frame: 4 weeks ] [ Designated as safety issue: No ]
  change in nailfold capillary microscopy finding during the fourth week of treatment from baseline, comparing active drug to placebo
• change of digital artery flow velocity [ Time Frame: 4weeks ] [ Designated as safety issue: No ]
  change of digital artery flow velocity during the fourth week of treatment from baseline, comparing active drug to placebo

The prevalence of Raynaud phenomenon (RP), a reversible vaso-constriction with skin discoloration, is 5-10% in general population. Often conventional measures such as warming up or minimizing exposure to cold are not enough and many patients require treatment with a vasodilator therapy. A recent study showed a good efficacy and safety profile of sildenafil, a selective inhibitor of cGMP specific phosphodiesterase type 5 (PDE5) in RP.

Here, the investigators aim to examine the efficacy and safety of Udenafil, a newer PDE5 inhibitor, as compared to amlodipine, a well known calcium channel blocker, in the treatment of secondary RP in Korean patients.

• Experimental: Amlodipine-Udenafil (AU) arm
  Amlodipine 10mg PO QD for 4 weeks, washout period, then Udenafil 100mg PO QD for 4 weeks
  Intervention: Drug: Udenafil or Amlodipine
• Experimental: Udenafil-Amlodipine (UA) arm
  Udenafil 100mg PO QD for 4 weeks, washout period, then Amlodipine 10mg PO QD for 4 weeks
  Intervention: Drug: Udenafil or Amlodipine

Inclusion Criteria:

• secondary Raynaud's phenomenon

Exclusion Criteria:

• primary raynaud phenomenon
• active infection
• hypersensitivity to PDE5 inhibitor or Calcium Chanel Blocker (CCB)
• elevated AST/ALT (3 times above the upper normal limit)
• severe renal failure
• patients on nitrite or nitric oxide (NO) donor treatment
• recent history of cerebrovascular accidents, acute myocardial infarction, or coronary artery bypass surgery
• hypotension (less than 90/50 mmHg) or uncontrolled hypertension