Phase 2B/3 Double-blinded Placebo-controlled

Phase 2B double-blind placebo-controlled efficacy trial of EVO100 (previously known as Amphora ® Gel) for the prevention of acquisition of urogenital Chlamydia trachomatis infection

Primary: To determine if intravaginal EVO100 reduces the risk of urogenital Chlamydia trachomatis (CT) infection.

Secondary: To determine if intravaginal EVO100 reduces the risk of urogenital Neisseria gonorrhoeae (GC) infection.

Exploratory:To determine if EVO100 use rate (subject adherence to instructed use) has an effect on proportion of subjects who experience CT or GC infection during the study intervention period.

Primary Outcome Measures: Proportion of subjects who experience urogenital CT infection during the study intervention period (incident infection of CT).

Secondary Outcome Measures: Proportion of subjects who experience urogenital GC infection during the study intervention period (incident infection of GC).

Exploratory Outcome Measures:

* Compliance with EVO100 usage during study (rate of product use adherence).
* Sensitivity analyses of the primary parameter (proportion of subjects who experience at least one CT or GC infection during the study intervention period) will be performed for the following:
* Subjects with ≥20%, ≥40%, ≥60% and ≥80% product use adherence
* Subject Satisfaction
* Sexual satisfaction

Eligibility Criteria:
Inclusion Criteria:

1. Healthy female subjects between 18 and 45 years, inclusive
2. Ability to understand the consent process and procedures
3. Subjects agree to be available for all study visits
4. Written informed consent in accordance with institutional guidelines
5. Negative pregnancy test
6. Negative CT and GC NAAT tests OR positive CT or GC NAAT and receives standard of care (SOC) treatment
7. Agree to use a woman-controlled method of contraception, such as oral contraceptives, vaginal ring, birth control implants, IUDs, or tubal ligation (with the exception of spermicides, diaphragms, or any vaginally applied or inserted products containing nonoxynol-9). Condom use only is not an acceptable form of contraception for this study.
8. Able and willing to comply with all study procedures
9. Documented (as part of a retrievable medical record) CT or GC infection within 16 weeks prior to enrollment
10. Reports vaginal sexual intercourse with a male partner at least 3 times per month in the previous month and anticipates vaginal sexual intercourse regularly for the duration of the study
11. Agree to abstain from douching or any form of vaginal suppository use (other than study product) during course of study

    -

Exclusion Criteria:

1. Participation in any study with an investigational compound or device within 30 days prior to signing informed consent
2. In the opinion of the Investigator, have a history of substance abuse in the last 12 months
3. In the opinion of the Investigator, have issues, conditions, or concerns that may compromise the safety of the subject, impact the subject's compliance with the protocol requirements, or confound the reliability of the data acquired
4. Be an Evofem, ClinicalRM, or clinical site employee regardless of direct involvement in research activities, or their close relative
5. Pregnant (or actively trying to become pregnant), or breast-feeding
6. Women who have undergone a total hysterectomy (had uterus and cervix removed)
7. Inability to provide informed consent
8. A subject with a history or expectation of noncompliance with medications or intervention protocol
9. Have engaged in sexual intercourse, douching or used of any form of vaginal suppository or intravaginal device for 24 hours prior to enrollment (may be enrolled at a later date if all other criteria are met)
10. Menstruating at enrollment (may be enrolled at a later date if all other criteria are met)
11. Women who are currently being treated, or have been treated, for a period of 14 days prior to enrollment, with specific antibiotics known to be used for the treatment of CT or GC:

    1. Azithromycin
    2. Erythromycin
    3. Tetracycline
    4. Minocycline
    5. Doxycycline
    6. Levofloxacin
    7. Ofloxacin
    8. Ceftriaxone
    9. Cefixime
12. In the opinion of the Investigator, has signs/symptoms that indicate persistence of chlamydia or gonorrhea infection diagnosed at screening, new interval infection and/or a failure to comply with or complete the prescribed treatment regimen following a positive screening NAAT.
13. Women who regularly use douches, vaginal medications, products, or suppositories
14. Women who are currently using contraceptive products that are directly delivered to the vaginal mucosa, such as diaphragms, vaginal rings (e.g. NuvaRing®), spermicides, or any vaginally applied or inserted products containing nonoxynol-9.
15. Children, pregnant women, prisoners, and other vulnerable populations