Patients diagnosed with bullous pemphigoid were confirmed based on the investigators national diagnostic criteria. Patients who meet all inclusion criteria and do not conflict with the exclusion criteria will receive NPB-01 (intravenous immunoglobulin) 400mg/kg/day for five consecutive days or Placebo(physiological saline). Subsequently, efficacy of NPB-01 for therapy of bullous pemphigoid will be evaluated the score using pemphigus disease area index (PDAI) and pemphigoid activity score involving skin lesion area and Number of new blisters.

As a safety endpoint, the safety of NPB-01 will be investigated the occurrence of adverse events by 57 days after the start of the study treatment.

Inclusion Criteria:

1. Patients with corticosteroids over 0.4mg/kg/day(Prednisolone) at informed consent.
2. Patients with continued treatment for bullous pemphigoid without add or change the treatment after informed consent.
3. Patients who the score using Pemphigus Disease Area Index(PDAI) is score10 and more before study medication received.
4. Patients who the score using Pemphigus Disease Area Index(PDAI) is not improve before study medication received.
5. Patients with twenty years old at informed consent.
6. Patients with hospitalization during five consecutive days of study medication and seven consecutive days after administration of study medication .

Exclusion Criteria:

1. Patients treated with plasmapheresis at 28 days before informed consent.
2. Patients treated with corticosteroids pulse therapy(methylprednisolone over 0.5g/day) at 14 days before informed consent.
3. Patients treated with intravenous immunoglobulin at 56 days before informed consent.
4. Patients who receive or adjust in increments immunosuppressants at 14 days before informed consent.
5. Patients with malignancy or a history of this disease.
6. Patients with history of shock for NPB-01.
7. Patients with history of hypersensitivity for NPB-01.
8. Patients with IgA deficiency.
9. Patients with impaired liver function.
10. Patients with impaired renal function.
11. Patients with cerebro- or cardiovascular disorders.
12. Patients with high risk of thromboembolism.
13. Patients with hemolytic/hemorrhagic anemia.
14. Patients with decreased cardiac function.
15. Patients with decreased platelet.