Chinese State Food And Drug Administration, Clinical Trial Permission No. 2003L02778
Effectiveness of BenZalKonium chloride gel as vaginal contraceptive: a randomised controlled trial among Chinese women
BZK contraceptive gel
A multicentric clinical trial in three Chinese Maternal and Child Hospitals was conducted to evaluate the efficacy, safety and acceptability of a newly-developed vaginal contraceptive gel, the optimised benzalkonium chloride (BZK) gel containing 18 mg BZK, with comparison to a currently marketed (in China) contraceptive gel Lelemi® containing 50 mg Nonoxynol-9 (N-9).
Ethics approval received from the Ethical Committee of International Peace Maternity and Child Care Centre, Shanghai (P.R. China) on the 5th March 2004.
Phase II multicentric randomised controlled trial
Primary study design
Secondary study design
Randomised controlled trial
Patient information sheet
Participants received either benzalkonium chloride gel or nonoxynol-9 gel as their primary method of contraception. All treatment arms were followed for six months.
The test drug, Benzakonium Chloride Contraceptive Gel (Brand name: Konrapo spermicide gel), was provided by Shanghai Institute of Planned Parenthood Research and Changjiang Bio-pharmaceutical Co. Ltd. 4.2 ml 0.429% BZK gel is filled in a disposable applicator for single use (18 mg BZK per piece), Lot No. 20040108. The gel is ready to use and should be inserted into vagina before every coital act. The drug action lasts for 24 hours, however, it is recommended to finish the coital act within 4 hours.
The control drug, Nonoxyno-9 Contraceptive Gel (Lelemi® Contraceptive Gel), was provided by Pharmaceutical Co. Ltd, Chinese Pharmaceutical University. Each piece of gel contains 50 mg N-9. The gel should be inserted into vagina within half an hour before each sexual intercourse. After the insertion, women are not allowed to walk and the sexual intercourse should be finished within half an hour. Otherwise, another piece should be inserted.
Benzalkonium chloride (BZK), nonoxynol-9 (Lelemi®)
Primary outcome measure
Contraceptive effectiveness. Outcomes were assessed at 2, 4 and 6-month follow-up visits.
Secondary outcome measures
1. Safety, evaluated based on gynaecological examination, cytobacteriological examinations, blood test, urine test, reporting adverse events, and termination due to medical reasons. An adverse event was a change in health status from that at baseline, regardless of its possible relationship with the product, consistent with good clinical practice guidelines.
2. Product acceptability, assessed through a standard questionnaire
Outcomes were assessed at 2, 4 and 6-month follow-up visits.
Overall trial start date
Overall trial end date
Reason abandoned (if study stopped)
Participant inclusion criteria
Eligibility requirements included:
1. Sexually active female
2. Aged 20 - 45 years old
3. Presumably fertile based on at least one delivery record
4. At risk for pregnancy and desiring contraception
5. Having regular menstrual cycle (21 - 35 days) and at least three normal menstrual cycles since the last pregnancy, abortion or hormone contraceptive use
6. Be willing to engage in at least four acts of sexual intercourse per month
7. Use the test products as their primary method of contraception
8. Keep a diary of coital activity, product use, and adverse events
9. At low risk for human immunodeficiency virus (HIV) or other sexually transmitted infection, which was defined as having a single sexual partner (for at least six months prior to study initiation)
10. The subject's sexual partner should not be presumably infertile, have a known allergy to BZK or N-9, or have been treated for sexually transmitted diseases (STDs) within six months prior to study entry
Target number of participants
Participant exclusion criteria
Exclusion criteria included:
1. Diagnosis of any vaginal infection or any symptom of STDs at baseline
2. Known allergy or hypersensitivity to N-9 or BZK
3. Menopause for more than one month
5. Vaginal bleeding with unknown reasons
6. Recurrent vaginitis or urinary infection
7. Genitourinary system anomaly
8. Hysteroptosis II or severe cystocele
9. Moderate to severe erosion of cervix
10. Malignant reproductive system tumours
Recruitment start date
Recruitment end date
Countries of recruitment
Trial participating centre
Shanghai Institute of Planned Parenthood Resarch
Shanghai Institute of Planned Parenthood Research (China) - World Health Organization (WHO) Collaborating Centre for Research in Human Reproduction
Funding Body Type
Funding Body Subtype
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Basic results (scientific)
1. 2012 results in https://www.ncbi.nlm.nih.gov/pubmed/23089047 (added 28/01/2019)