Phase III Study of ASP2151 in Herpes Zoster Patients

Phase III Study of ASP2151 in Herpes Zoster Patients- A Double-blind, Valaciclovir-controlled Study

To evaluate the efficacy and safety of ASP2151 (200 mg and 400 mg) in comparison with valaciclovir (VACV) 3000 mg in patients with herpes zoster.

A double-blind, randomized, parallel-group study will be conducted to evaluate the efficacy and safety of ASP2151 (200 mg and 400 mg) in comparison with valaciclovir (VACV) 3000 mg in patients with herpes zoster. The efficacy will be evaluated for the primary endpoint defined as, "the proportion of subjects achieving cessation of new lesion formation by Day 4 of study treatment" to demonstrate the non-inferiority of ASP2151 to VACV. The safety will be evaluated based on adverse events, laboratory tests, vital signs, and ECGs.

Inclusion Criteria:

(1) Patients who have a rash associated with herpes zoster, and who can start receiving the study drug within 72 hours after onset of the rash

Exclusion Criteria:

1. Patients who are not expected to have an adequate response to oral antiviral medication

2. An extreme decline in immune function

3. Presence of serious complications

4. Patients found to meet any of the following conditions based on laboratory tests performed within 14 days before informed consent:

   • AST or ALT ≥ 2.5 x upper limit of normal
   • Platelet count < lower limit of normal
   • Serum creatinine ≥ 1.5 mg/dL
   • Creatinine clearance < 50 mL/min

5. Current or previous history of malignant tumor within 5 years before informed consent

6. Diagnosis of autoimmune disease

7. Evidence of bone marrow suppression