Intravaginal LACTIN-V for Prevention of Recurrent Urinary Tract Infection

Purpose: The purpose of this study is to evaluate the safety of the vaginal suppository LACTIN-V (Lactobacillus crispatus CTV-05) as well as the efficacy of LACTIN-V use in preventing recurrent urinary tract infections (RUTI) in women. Study subjects will include pre-menopausal women with a history of frequent RUTI. As part of this study, we will also evaluate growth of lactobacilli and urinary tract infection(UTI)-causing bacteria in the vaginas of women following use of LACTIN-V.

Rationale: LACTIN-V is composed of L. crispatus. L. crispatus is a bacteria found to grow naturally in the vaginas of healthy women. It is felt to be important in preventing vaginal infection and UTI. With regard to prevention of UTI, L. crispatus is thought to prevent the growth of UTI-causing bacteria (such as E. coli) in the vagina, and so prevent these UTI-causing bacteria from being able to enter the female urethra and cause infection in the bladder (cystitis). There is epidemiologic evidence to support this prevention mechanism, as absence of L. crispatus and related lactobacilli from the vagina has been associated with vaginal E. coli growth and with UTI. Scientific evidence supports the ability of lactobacilli to prevent vaginal E. coli growth by out-competing E. coli in vaginal colonization, and through the production of toxins such as lactic acid, hydrogen peroxide, and bacteriocins.

LACTIN-V contains a specific strain of L. crispatus, CTV-05, which was isolated from the vagina of a healthy woman. It was prepared as a vaginal suppository with the purpose of restoring growth of healthy L. crispatus in the vaginas of women who experience frequent RUTI. As indicated above, these women often have a deficiency of healthy vaginal lactobacilli growth, and therefore may not experience the protective function of these natural organisms. It is hoped that use of LACTIN-V will lead to vaginal growth of protective lactobacilli in these women wich will, in turn, prevent the vaginal growth of E. coli and other UTI-causing bacteria. Phase 1 and 2 studies of LACTIN-V to date have shown this "probiotic" to be safe and well tolerated.

The impetus for this study is the urgent need for non-antibiotic strategies to prevent UTI. UTI is one of the most common bacterial infections. It leads to substantial morbidity and health care costs. Frequent use of antibiotics for treatment of and prophylaxis against UTI is contributing to the prevalence of antibiotic resistant bacteria, which are also making it more difficult to treat UTI. Therefore, the potential advantage of LACTIN-V is that it is a natural product that may prevent UTI without the use of antibiotics. If it proves to be efficacious, it could decrease the morbidity and health care costs associated with UTI as well as decrease overall antibiotic use and the corresponding prevalence of antibiotic resistance among UTI-causing bacteria.

Primary Objective: The primary objective is to evaluate the safety of LACTIN-V, compared to placebo, in pre-menopausal women with recurrent uncomplicated UTI.

Secondary objectives:

1. To evaluate the efficacy of LACTIN-V, compared to placebo, in reducing the incidence of Symptomatic and Probable UTI (defined below).
2. To evaluate the efficacy of LACTIN-V, compared to placebo, in decreasing the time to recurrence of Symptomatic and Probable UTI.
3. To evaluate the efficacy of LACTIN-V, compared to placebo, in reducing the prevalence of Asymptomatic UTI (defined below).
4. To evaluate vaginal growth of CTV-05 in subjects using LACTIN-V compared to placebo.
5. To evaluate vaginal growth of lactobacilli in subjects using LACTIN-V compared to subjects using placebo.
6. To evaluate vaginal growth of E. coli in subjects using LACTIN-V compared to subjects using placebo.

Case Definitions:

Symptomatic UTI: One or more UTI symptoms (dysuria, urgency, frequency, suprapubic pain, flank pain), with a positive urine culture. In symptomatic subjects, a positive urine culture is defined as >= 10^2/ml of an UTI-causing bacteria. UTI episodes will be recorded as Symptomatic UTI if a negative urine culture at Visit 2, or at another interim study visit, confirms resolution of the prior UTI (in order to distinguish a new Symptomatic UTI from a Persistent UTI).

Asymptomatic UTI: A positive urine culture in a subject who reports no urinary symptoms. In asymptomatic subjects, a positive urine culture is defined as >= 10^5/ml of an UTI-causing bacteria. UTI episodes will be recorded as Asymptomatic UTI if a negative urine culture at Visit 2, or at another interim study visit, confirms resolution of the prior UTI (in order to distinguish a new Asymptomatic UTI from a Persistent UTI).

Probable UTI: One or more UTI symptoms (dysuria, urgency, frequency, suprapubic pain, flank pain) in a subject who contacted a healthcare provider and was treated with antibiotics for a UTI without confirmatory urine culture. UTI episodes will be recorded as Probable UTI if a negative urine culture at Visit 2, or at another interim study visit, confirms resolution of the prior UTI (in order to distinguish a new Probable UTI from a Persistent UTI).

Persistent UTI: A positive urine culture following antibiotic treatment for a UTI.

General Procedures: This will be a randomized, double-blind, placebo-controlled trial of LACTIN-V. Subjects will include 100 pre-menopausal women with a history of frequent RUTI who are currently or recently being treated for a symptomatic UTI with trimethoprim-sulfamethoxazole. Trimethoprim-sulfamethoxazole is one of several antibiotics considered standard-of-care for treatment of symptomatic UTI. Subjects will be randomized such that 50 women will receive LACTIN-V at a dose of 5x10^8 CFU/suppository and 50 women will receive placebo. LACTIN-V and placebo are to be taken once per day for five days during the first week of use followed by once per week for 10 weeks on Days 8, 15, 22, 29, 36, 43, 50, 57, 64, and 71 for a total of 15 doses over 11 weeks. Subjects will undergo five scheduled visits and receive two telephone calls:

Visit 1 is the Screening Visit. This visit will take place during or soon after evaluation for a symptomatic UTI. The following will occur during Visit 1: informed consent, review of eligibility, history, physical exam, pelvic exam, Pap smear, urine pregnancy test, and screening tests for gonorrhea, chlamydia, bacterial vaginosis, yeast, and trichomonas. Subjects will provide urine samples for microscopic analysis, dipstick analysis, culture, and antibiotic susceptibility testing and vaginal fluid specimens for laboratory assessment of vaginal growth of lactobacilli (including CTV-05).

Visit 2 is the Randomization Visit and represents Week 1 of the study. Visit 2 will take place 3-10 days after completion of antibiotic therapy for UTI. Subjects will have their eligibility confirmed and undergo a focused pelvic exam without speculum or bimanual exam unless clinically indicated, have a screening test for bacterial vaginosis, yeast, and trichomonas, and have a repeat pregnancy test. Subjects will also provide urine and vaginal fluid specimens as in Visit 1. Subjects will then be randomized to LACTIN-V or placebo. Subjects will place the first suppository under supervision and will be instructed to use a 7-day study calendar to record study product use and related symptoms during the first week, and to use a 10-week study calendar to record study product use and related symptoms thereafter.

Day 4-7 phone call: The purpose of this phone call is to assess use of the study product as well as any associated symptoms.

Visit 3 will occur during Week 2, days 8-14 following randomization. Subjects will be asked about study product use, adverse events, and symptoms. Subjects will undergo focused physical and pelvic exams without speculum or bimanual exam unless clinically indicated. Subjects will have a screening test for bacterial vaginosis and provide urine and vaginal fluid specimens as before.

Visit 4 will occur during Week 11 and will be similar to Visit 3.

Visit 5 will occur during Week 16. The procedures for Visit 5 will be similar to those of Visits 3 and 4. However, during this visit, subjects will undergo a complete pelvic exam including speculum and bimanual exams and undergo a repeat pregnancy test.

9 Month telephone call: The purpose of this phone call is to assess the occurrence of adverse events, symptoms of UTI, new UTI or other medical diagnoses,and pregnancy.

In addition to the above schedules visits, subjects will be asked to come to the research clinic for Unscheduled Visits if they experience any adverse events or new symptoms of UTI. During these unscheduled visits, subjects will undergo history, physical and complete pelvic exams, screening tests for bacterial vaginosis, yeast, and trichomonas, as well as for other sexually transmitted diseases as clinically indicated. Subjects will provide urine samples for microscopic analysis, dipstick analysis, culture, and antibiotic susceptibility testing. Subjects will provide vaginal fluid samples for assessment of CTV-05, lactobacillus, and E. coli growth.

Subjects diagnosed with a Symptomatic UTI during the study will be treated with an antibiotic. They will then be asked to return to the study clinic for a follow-up urine culture two weeks later to confirm UTI resolution.

Laboratory procedures will include:

• wet mount slides of vaginal fluid (all Visits)
• urine dipstick testing (all Visits)
• urine pregnancy testing (Visits 1, 2, and 5)
• Pap smear (Visit 1)
• Testing for gonorrhea and chlamydia by culture (Visit 1, other visits as indicated)
• urinalysis (all Visits)
• urine culture (all Visits)
• gram stain and culture of vaginal fluid specimens (All Visits)
• Rep-PCR for CTV-05 (Visits 2-5)
• DNA amplification of vaginal flora (all Visits)

Statistical Analysis: The primary cohort for analysis will be the intent-to-treat (ITT) cohort. The ITT cohort is defined as subjects who are randomized in the study. Other cohorts to be evaluated will include the modified ITT, Evaluable, and according-to-protocol cohorts.