Bacterial Vaginosis (BV)Phase 2NCT07888699
WST03 Capsule Combined With Metronidazole for Bacterial Vaginosis
A Phase 2 study testing High-dose WST03 Vaginal Capsule Metronidazole and Low-dose WST03 Vaginal Capsule Metronidazole in people with Bacterial Vaginosis (BV), run by SPH Sine Pharmaceutical Laboratories Co., Ltd. at 14 sites in China.
Trial summary
This is a multicenter, randomized, double-blind, placebo-controlled Phase 2 trial enrolling approximately 150 pre-menopausal women with bacterial vaginosis (BV). Participants will be randomized 1:1:1 to three groups. All participants will receive oral metronidazole 0.4 g twice daily for 7 days. Read more about this study
- Who is it for?
- Ages 18 to 55 years, women only
- Conditions the study is for
- Bacterial Vaginosis (BV)
- What is being tested?
- High-dose WST03 Vaginal Capsule Metronidazole and Low-dose WST03 Vaginal Capsule Metronidazole
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 150 participants
- Where
- 14 sitesChina
- Study dates
- 20 Oct 2026to 25 Dec 2027
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 55 years
- Women only
- No healthy volunteers
- Adult
Who may be able to join
- Pre-menopausal female aged 18-55 years inclusive.
- Regular menstrual cycle of 21-35 days.
- Clinically diagnosed bacterial vaginosis: at least 3 of 4 Amsel criteria positive with mandatory clue-cell positive; screening Nugent score ≥7.
- No prior treatment for current episode of BV.
- Sexually active history; willing for vaginal drug administration; agree to avoid prohibited vaginal products and comply with sexual activity restrictions per protocol.
- No pregnancy plan during study and within 3 months after last study dose, agree to use effective barrier contraception.
- Voluntarily sign informed consent form and be able to comply with all study procedures.
Who cannot join
- Current pelvic inflammatory disease, cervicitis or acute genitourinary infection.
- Other genital tract infections including vulvovaginal candidiasis, trichomoniasis, aerobic vaginitis, gonorrhea, genital herpes, condyloma acuminata.
- Unexplained vaginal bleeding; uterine leiomyoma, endometrial hyperplasia or adenomyosis interfering with study assessment.
- Systemic/vaginal antibacterial or microecological agents within 2 weeks prior to randomization or planned use; vaginal douching / local vaginal therapy within 1 week.
- Other vaginal infection diagnosed within 2 weeks before randomization except current index BV episode.
- Long-acting injectable contraceptives / sustained-release contraceptives without required wash-out.
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- Planned systemic steroid therapy within 2 weeks prior to randomization.
- Use of disulfiram; systemic alcohol- or propylene-glycol-containing products within 3 days before randomization or planned use, with known interaction with metronidazole.
- Major gynecologic surgery within 6 months; superficial gynecologic procedures within 60 days; pregnancy termination less than 60 days.
- History of complicated / recurrent vulvovaginal candidiasis within 1 year before ICF.
- Malignancy within past 5 years (except basal-/squamous-cell skin carcinoma, papillary thyroid carcinoma, cervical carcinoma in-situ).
- Obvious vaginal mucosal injury on gynecological examination.
- Intrauterine device in-situ at screening.
- Abnormal cervical cytology or positive HPV-16 / HPV-18.
- Abnormal lab parameters: Neutrophil<1.5×10⁹/L; Hb ≤90g/L; platelet<75×10⁹/L; liver-renal function over 1.5-2×ULN; positive HIV or syphilis test.
- Known hypersensitivity to metronidazole, WST03 investigational product or similar vaginal lactobacillus preparations.
- History of alcohol or drug abuse.
- Psychiatric disorder making subject unable to comply with study.
- Pregnant or lactating female.
- Participation in another clinical trial within 4 weeks before randomization.
- Previous participation in any WST03-related clinical trial.
- Any other condition judged by investigator making subject unsuitable for enrollment.
Trial locations and contacts
14 sites in 1 country. Contact the study team or a site near you to ask about taking part.
14 sites in 1 country
China14 sites
Beijing Tsinghua Changgung Hospital
Beijing, Beijing Municipality
Peking University First Hospital
Beijing, Beijing Municipality
Bingbing Xiao
The Second Hospital of Jilin University
Changchun, Jilin
Tianmin Xu
Chengdu Women's and Children's Central Hospital
Chengdu, Sichuan
Qianling Dai
The Second Affiliated Hospital of Chongqing Medical University
Chongqing, Chongqing Municipality
Xiaojing Dong
Women's Hospital, Zhejiang University School of Medicine
Hangzhou, Zhejiang
Xiufeng Huang
Liuzhou Maternal and Child Health Hospital
Liuzhou, Guangxi
Shanghai First Maternity and Infant Hospital
Shanghai, Shanghai Municipality
Xiaowen Pu
Shenzhen University of Technology General Hospital
Shenzhen, Guangdong
Patiman Mijiti
Taihe Hospital, Shiyan City
Shiyan, Hubei
Caiyun Fang
The Second Hospital of Shanxi Medical University
Taiyuan, Shanxi
Min Hao
The First Affiliated Hospital of Xi'an Jiaotong University
Xi'an, Shaanxi
Ruifang An
The First Affiliated Hospital of Henan Medical University
Xinxiang, Henan
Jun Yang
Zhuzhou Maternal and Child Health Hospital
Zhuzhou, Hunan
Jiqing Wang
About this study
Official title: A Multicenter, Randomized, Double-Blind, Placebo-Controlled PhaseⅡ Study to Evaluate the Efficacy and Safety of WST03 Capsule Combined With Metronidazole for Bacterial Vaginosis
This is a multicenter, randomized, double-blind, placebo-controlled Phase 2 trial enrolling approximately 150 pre-menopausal women with bacterial vaginosis (BV). Participants will be randomized 1:1:1 to three groups. All participants will receive oral metronidazole 0.4 g twice daily for 7 days. In addition, participants will take vaginal capsules (high-dose WST03, low-dose WST03, or matched placebo) once daily for 14 days. The primary endpoint is cumulative BV recurrence rate at Week 12. This trial evaluates the efficacy and safety of WST03 plus metronidazole for lowering BV recurrence and explores its impact on vaginal microecology.
- Conditions
- Bacterial Vaginosis (BV)
- Being tested
- High-dose WST03 Vaginal Capsule Metronidazole, Low-dose WST03 Vaginal Capsule Metronidazole, Placebo Vaginal Capsule Metronidazole
- Medical subject headings
- Vaginosis, Bacterial
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
High-dose WST03 Vaginal Capsule MetronidazoleDrug
High-dose vaginal capsule containing multi-strain live lactobacilli; vaginal administration, once daily for 14 consecutive days (Day 1-14).
Metronidazole 0.4 g twice daily for 7 days (Day1-7).
Low-dose WST03 Vaginal Capsule MetronidazoleDrug
Low-dose vaginal capsule containing multi-strain live lactobacilli; vaginal administration, once daily for 14 consecutive days (Day 1-14).
Metronidazole 0.4 g twice daily for 7 days (Day1-7).
Placebo Vaginal Capsule MetronidazoleDrug
Placebo vaginal capsule, visually identical to WST03 capsule, vaginal administration, once daily for 14 consecutive days (Day1-14).
Metronidazole 0.4 g twice daily for 7 days (Day1-7).
| Study group | Role | What they receive |
|---|---|---|
| High-dose WST03 Group | Experimental | Participants will receive high-dose WST03 vaginal capsule and oral metronidazole. Receives: Drug: High-dose WST03 Vaginal Capsule Metronidazole |
| Low-dose WST03 Group | Experimental | Participants will receive low-dose WST03 vaginal capsule and oral metronidazole. Receives: Drug: Low-dose WST03 Vaginal Capsule Metronidazole |
| Placebo Control Group | Placebo comparator | Participants will receive visually matched placebo vaginal capsule and oral metronidazole. Receives: Drug: Placebo Vaginal Capsule Metronidazole |
What is being measured
The primary outcome is the main question the study is designed to answer.
Cumulative recurrence rate of bacterial vaginosis (BV) up to Week-12 visit
Percentage of participants with BV recurrence through Week 12 among those who achieve composite cure at or before Week 4.
Measured: From first study drug administration up to Week-12 visit
Secondary outcomes (7)
BV clinical cure rate at Day-8, Day-15, Week-4 visits
Percentages of participants achieving protocol-defined clinical cure at each visit.
Measured: Day8, Day15, Week4
BV bacteriological cure rate at Day-8, Day-15, Week-4 visits
Percentages of participants achieving protocol-defined bacteriological cure at each visit.
Measured: Day8, Day15, Week4
BV composite cure rate at Day-8, Day-15, Week-4 visits
Percentages of participants achieving protocol-defined composite cure at each visit.
Measured: Day8, Day15, Week4
Cumulative BV recurrence rate up to Week-4 and Week-8 visits
Percentage of participants with BV recurrence through Weeks 4 and 8 among those who achieve composite cure at or before Week 4.
Measured: Up to Week-4, Week-8
Time to first BV recurrence
Time from composite cure to first BV recurrence among participants who achieve composite cure at or before Week 4.
Measured: From composite cure up to Week-12
adverse events during treatment and follow-up period
Adverse events summarized by participant counts and severity (mild, moderate, or severe)
Measured: up to 12 weeks
laboratory abnormalities during treatment and follow-up period
abnormal laboratory test results will be listed.
Measured: up to 12 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Oct 2026
- Study start20 Oct 2026 (estimated)
- Primary completion15 Oct 2027 (estimated)
- Study completion25 Dec 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Bacterial Vaginosis (BV)Studies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 150 participants (estimated)
Sponsor and investigators
- Lead sponsor
- SPH Sine Pharmaceutical Laboratories Co., Ltd.
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07888699
- Sponsor's protocol ID
- SPH-XY-WST03-201
- Status last verified
- Oct 2026
- First submitted
- 29 Sep 2026
- Last updated
- 22 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No