Inclusion Criteria:
* Participants who have fully understood the study, able and willing to comply with all study procedures, and voluntarily sign written ICF;
* Female participants aged 18-60 years (inclusive) at the time of signing the ICF;
* Persistent HPV16 infection, defined as virologically confirmed HPV16 positivity persisting for ≥ 6 months before screening (e.g., participants must provide investigator-approved evidence of HPV16 infection ≥ 6 months prior to screening and be HPV16 positive at the time of screening);
* Participants must have a confirmed cytological results of atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion (ASC-H) or high-grade squamous intraepithelial lesion (HSIL) at the time of screening (histopathological confirmed cervical/vaginal/vulvar LSIL are acceptable but not required);
* Satisfactory colposcopy at screening;
* Normal major organ functions at screening;
* Women of child-bearing potential must have a negative serum pregnancy test result at screening. All WOCBP participants agree to voluntarily use effective contraception, from signing the ICF to the end of the study. In addition, female participants must agree not to donate eggs during this period.
Exclusion Criteria:
* Histopathological confirmed high-grade cervical, vulvar, vaginal or anal intraepithelial lesions (including endocervical adenocarcinoma-in-situ \[AIS\]) or invasive cancer, OR cervical cytology results showing squamous cell carcinoma (SCC), atypical glandular cells (AGC), or AIS at screening;
* Negative for HPV16 as confirmed by real-time quantitative polymerase chain reaction (RT-qPCR) at screening;
* Comorbid infectious diseases, such as acute pelvic inflammatory disease, urinary tract infection, or other active infections requiring systemic treatment prior to the first injection;
* Participants with unresolved vaginal/cervical conditions prior to the first injection that could affect clinical response (e.g., common sexually transmitted infections such as gonorrhoea, genital herpes, etc.);
* Positive serological test results at screening for human immunodeficiency virus (HIV), treponema pallidum antibody, or hepatitis B virus surface antigen (HBsAg) positive; or hepatitis C virus antibody (HCV-Ab) positive and hepatitis C virus (HCV) ribonucleic acid (RNA) quantitative \> the lower limit of the positive detection value of the study site;
* Significant abnormalities at the screening ECG, including QTc interval \> 470 msec (average of triplicate measurements corrected for heart rate using Fridericia's formula), or history/presence of clinical symptoms of cardiac diseases that is not well controlled, such as New York Heart Association (NYHA) Class 2 or higher heart failure, unstable angina, myocardial infarction within the past 6 months, and clinically significant supraventricular or ventricular arrhythmia requiring treatment or intervention;
* Systemic corticosteroid use (e.g., \> 10 mg/day prednisone for \> 1 week) within 30 days before screening, excluding hormone replacement therapy and local/topical use (e.g., ocular, intratracheal);
* Immunosuppressant use (\> 1 week) within 30 days or 5 drug half-lives (whichever is longer) before screening (including but not limited to cyclosporine, tacrolimus, azathioprine, 6-mercaptopurine, or antilymphocyte globulin);
* Current or planned use of disease-modifying antirheumatic drugs (DMARDs, e.g., azathioprine, cyclophosphamide, cyclosporine, methotrexate) or biologic DMARDs (e.g., infliximab, adalimumab, etanercept) during the study;
* Received any vaccine (other than HPV prophylactic vaccines) within 8 weeks before screening or plan to receive any vaccine during the study;
* History of therapeutic HPV vaccination.
