This study is to follow up on the change of immune response by measuring HPV type 16/18 E6 and E7 specific T cell response and lesion condition in subjects who have administered in DNA-based therapeutic vaccine.

This is a follow-up study to investigate the change of immunogenicity and lesion condition in subjects with cervical intraepithelial neoplasia (CIN) 3 who have enrolled and completed GX-188E phase I study.

Subjects will make visits at week 48 (V1) to week 228 (V8) every 6 months after the final administration of GX-188E.

The endpoints are to evaluate the change of immune response, involved lesion and infection status compared to that of the final visit in phase I study.

Inclusion Criteria:

• Female aged between 20 and 50 (inclusive)
• The subjects who have visited within 48 weeks after final injection of GX-188E
• Those who voluntarily signed informed consent form

Exclusion Criteria:

• Prior participation in any clinical trial within 30 days prior to the visit 1
• Any other ineligible condition at the discretion of the investigator that would be ineligible to participate the study

The subjects who have completed the DNA vaccine administration of each dosage (1, 2 and 4 mg).

The subjects in the period less than 48 weeks after the final administration of GX-188E