MucoCept-CVN: a vaginal Lactobacillus product to help prevent HIV

Phase 1 Randomized Double-Blind Placebo-Controlled Safety Study of MucoCept-CVN (Lactobacillus Jensenii 1153-1666) Administered Vaginally to Healthy Women

This trial will test whether a modified vaginal Lactobacillus that produces an anti‑HIV protein is safe and can colonize the vagina in healthy premenopausal women.

Quick facts

• Phase: PHASE1
• Study type: Interventional
• Enrollment: 12 (estimated)
• Ages: 18 Years to 45 Years
• Sex: Female
• Sponsor: University of California, San Francisco (other)
• Locations: 1 site (San Francisco, California)
• Trial ID: NCT07181486 on ClinicalTrials.gov

What this trial studies

This is a first‑in‑human, Phase 1 dose‑ranging, randomized placebo‑controlled trial enrolling 12 healthy premenopausal women to collect safety and colonization data. Participants receive one or three doses of an engineered Lactobacillus jensenii (MucoCept‑CVN) or placebo, followed by antibiotics to clear the strain. Outcomes include adverse events, colposcopy and biopsy findings, persistence of the strain, and changes to the vaginal microbiota. Participants are followed closely for clearance and have a final visit about 30 days after clearance.

Who should consider this trial

Good fit: Healthy premenopausal women aged 18–45 with regular menstrual cycles who can read English, tolerate gynecologic exams, agree to sexual abstinence during the study period, and can attend frequent visits at UCSF are ideal candidates.

Not a fit: Women with HIV infection, pregnant or breastfeeding women, postmenopausal women, or anyone unwilling/unable to comply with abstinence and frequent clinic visits are unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, MucoCept‑CVN could become a long‑acting, self‑renewing, female‑initiated product that promotes vaginal health and lowers women's risk of HIV.

How similar studies have performed: Using native Lactobacillus to promote vaginal health is established, but engineered live biotherapeutics that secrete anti‑HIV proteins are largely novel and have limited prior human data.

Eligibility criteria

Inclusion Criteria:

1. Healthy pre-menopausal women 18-45 years of age, inclusive, with regular predictable menstrual cycles
2. Ability to read and consent in English
3. Previous experience of gynecological examinations
4. Consent to participate and adhere to all procedures, including frequent visits at the UCSF Clinical Research Center (CRC) facility for at least 53 days
5. Agree to get tested for STIs and a Pap Smear
6. Agree not to use any other vaginal product during the course of the study, including spermicides
7. Agree to sexual abstinence (no vaginal, anal, and receptive oral intercourse) until the elimination of L. jensenii 1153-1666 is confirmed and for 12 hours prior to the final study visit after clearance is confirmed
8. For participants with male sexual partners: Agree to use two forms of contraception, condoms plus hormonal or permanent method (intrauterine device \[IUD\] or tubal ligation) during vaginal intercourse from the time clearance is established to the Final Visit 30 days after clearance. Use of spermicides is not permitted.
9. For participants with female sexual partners: Agree to use female condoms during intercourse from the time clearance is established to the Final Visit 30 days after clearance. Use of hormonal or permanent method of contraception (IUD or tubal ligation) is not required.
10. Agree to inform their sexual partner about the goals of the study and importance of sexual abstinence (no vaginal, anal, and receptive oral intercourse) and present with their partner at enrollment visit for separate consent procedure for partners

Current sexual partners of participants must meet all the following criteria to be enrolled:

1. Ability to read and consent in English
2. Consent to participate and adhere to all procedures for sexual partners should exposure to L. jensenii 1153-1666 be suspected, including multiple visits at the UCSF Clinical Research Center (CRC)
3. Agree to sexual abstinence (no vaginal, anal, and receptive oral intercourse) until the elimination of L. jensenii 1153-1666 is confirmed, and for 12 hours prior to the final study visit after clearance is confirmed

Exclusion Criteria:

1. Urogenital infection, including UTI, Trichomonas vaginalis, Neisseria gonorrhoeae, Chlamydia trachomatis, Treponema pallidum, HIV-1/2, BV, or vulvovaginal candidiasis
2. Abnormal Pap smear result
3. Pregnancy or within two months of last pregnancy or lactation
4. Antibiotic or antifungal therapy (vaginal or systemic) within 30 days of enrollment
5. Investigational or immune-suppressive drug use within 30 days of enrollment visit or 10 half-lives, or planned during the study
6. Intrauterine device insertion or removal, pelvic surgery, cervical cryotherapy, cervical laser or loop electrosurgical procedure, abortion, labioplasty within three months prior to enrollment
7. Findings during the pelvic exam at the enrollment visit involving significant deep disruption of the epithelium (e.g., Herpes genitalis lesions)
8. Known allergy to any component used in MucoCept-CVN or clindamycin and azithromycin in participant or sexual partner(s), including azithromycin-associated cholestatic jaundice.
9. History of transplant surgery, cancer, HIV, diabetes or condition that could facilitate the growth of microorganisms
10. Recent history of drug or alcohol abuse
11. Unwillingness to abstain from sexual activity during study by participant or sexual partner(s)
12. If in a sexual relationship, inability to present with their sexual partner before enrollment
13. If in a sexual relationship, having multiple concurrent partners or anonymous partners.
14. Any other condition which the study clinician feels would limit the participant's ability to be an appropriate study subject
15. History of regional enteritis (Crohn's disease), ulcerative colitis, or "antibiotic-associated" colitis

For sexual partners of study participants, the following exclusion criteria apply:

1. Known allergy to any component used in MucoCept-CVN or clindamycin and azithromycin, including azithromycin-associated cholestatic jaundice.
2. Having multiple concurrent sex partners or anonymous sex partners.
3. HIV-1/2 infection
4. Any other condition which the study clinician feels would limit the ability of sexual partner(s) to complete the study
5. Co-enrollment in clinical trials testing study drugs

Where this trial is running

San Francisco, California

• UCSF Zuckerberg San Francisco General Hospital — San Francisco, California, United States (RECRUITING)

Study contacts

• Principal investigator: Craig Cohen, MD, MPH — University of California, San Francisco
• Study coordinator: Anke Hemmerling, MD, PhD, MPH

Conditions: HIV -1 Infection, HIV prevention, live biotherapeutic product, MucoCept-CVN, Vaginal microbiome