UB-621, a New Type of Anti-herpes Simplex Virus (HSV) Monoclonal Antibody for the Use in the Treatment of Adult Recurrent HSV-2 Infections of the Genitals

Inclusion Criteria: * Subject must be at least 18 years of age inclusive. * Subject must be HSV-2 seropositive * Subjects have a history of recurrent genital herpes in the past year * Subjects have a negative result on the HIV Ab/Ag assay * Subjects must agree to use contraception during study participation * Subjects must be willing to collect a swab each day from their genital area (non-lesional as well as lesional, if appropriate) during the swabbing periods, which are 8 weeks period after the administration of study drug. * Subject must be willing to go back to the hospital within 72 hours after the new lesions are shown in the anal and genital area. * Subject must be willing to observe the syndromes around the anal and genital area during study period, to evaluate the lesions according to the HSV lesion score, and to record in the patient dairy * Female subjects must have a negative serum β-HCG at Screening and a negative urine pregnancy test prior to study drug administration. Exclusion Criteria: * Serious medical conditions, including poorly controlled diabetes, significant autoimmune diseases, co-existing sexually transmitted disease presentation (except HSV) in the anogenital area, etc. that may interfere with the assessment of the efficacy of UB-621. * History or current evidence of malignancy except for a localized non-melanoma skin cancer * Known immunosuppression * Exposure to HSV vaccine * Medical history of macular or maculopapular skin reactions to antibody (ie, as evidenced by IgG or plasma administration) * Any other conditions that in the judgment of the Investigator would preclude successful completion of the clinical study * Treatment with systemic steroids or other immunomodulating agents within 30 days prior to Screening or planned treatment with systemic steroids or immunomodulators during the study period. * Renal impairment and/or hepatic impairment * ECG abnormalities of clinical relevance or cardiovascular conditions * Abnormal blood tests according to "Toxicity Grading Scale for Healthy Adult and Adolescent Volunteers Enrolled in Preventive Vaccine Clinical Trial "in the Guidance for Industry, 2007: 1. albumin\<3 g/dl 2. ALP\>2.5\*ULN 3. ALT\>2.5\*ULN 4. AST\>2.5\*ULN 5. Bilirubin\>1.5\*ULN 6. CPK\>1.5\*ULN 7. rGGT\>2.5\*ULN 8. Hemoglobin: female\<11 g/dl; male\<12.5 g/dl 9. platelet\<125\*10E3/ul 10. WBC\<2.5\*10E3/ul or 11. ANC\<1.5\*10E3/ul