Lactic Acid Gel for Vaginal Infections

Overseen By Olivia H Manayan, MD, MPH

Age: 18 - 65

Sex: Female

Trial Phase: Phase < 1

Sponsor: Queen's Medical Center

Disqualifiers: Pregnant, Post-menopausal, Kidney disease, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 1 Jurisdiction This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 1

Duration: 4 weeks

22 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests whether the contraceptive gel Phexxi (lactic acid gel) can alter the vaginal bacterial balance, potentially reducing infections like bacterial vaginosis (BV) and yeast infections. Researchers believe Phexxi may promote the growth of beneficial bacteria that produce lactic acid. Women who have experienced two or more BV or yeast infections in the past year and are not using Phexxi as their contraceptive may qualify for this study. Participants will apply the gel twice a week and follow specific instructions. As an Early Phase 1 trial, this research aims to understand how Phexxi works in people, offering participants a chance to contribute to groundbreaking insights.

Will I have to stop taking my current medications?

The trial information does not specify if you need to stop taking your current medications. However, if you are using Phexxi as a contraceptive, you cannot participate in the study.

Is there any evidence suggesting that this treatment is likely to be safe for humans?

Research has shown that Phexxi is safe when used as directed. This contraceptive gel contains ingredients such as lactic acid, citric acid, and potassium bitartrate, which are generally safe for vaginal use. In studies involving over 4,700 women, about 1% experienced side effects, which were usually mild. Some users reported urinary tract infections, but these were rare and affected only a few individuals. Overall, Phexxi is considered a safe option for those exploring contraceptive methods. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Most treatments for vaginal infections involve antibiotics or antifungal medications that target the infection-causing organisms. But Phexxi works differently by using lactic acid to create an inhospitable environment for harmful bacteria and yeast, helping to maintain a healthy vaginal pH balance. This non-antibiotic approach is exciting because it reduces the risk of antibiotic resistance and preserves the natural balance of good bacteria. Moreover, Phexxi is a gel delivered via pre-filled vaginal inserters, offering a convenient and user-friendly application method.

What evidence suggests that Phexxi might be an effective treatment for vaginal infections?

Research shows that Phexxi, a vaginal gel, might help prevent bacterial vaginosis (BV) and yeast infections. One study found that the lactic acid in Phexxi worked as well as metronidazole, a common BV treatment. Phexxi contains lactic acid, citric acid, and potassium bitartrate, which may promote the growth of beneficial bacteria in the vagina. This increase in good bacteria could help prevent infections. While most studies on Phexxi focus on its use as birth control, its ingredients also appear promising for maintaining vaginal health. Participants in this trial will receive Phexxi to evaluate its effectiveness for vaginal infections. ^{2 6 7 8 9}

Who Is on the Research Team?

Olivia Manayan, MD, MPH

Principal Investigator

University of Hawaii

Bliss Kaneshiro, MD, MPH

Principal Investigator

Queen's Medical Center

Corrie Miller, DO

Principal Investigator

University of Hawaii

Are You a Good Fit for This Trial?

This trial is for pre-menopausal females aged 18-54 who have had at least two episodes of BV or candida infection in the past year. Participants must speak English and be able to consent. Those with current UTIs, pregnancy, post-menopause status, NuvaRing use, kidney issues, or using Phexxi are excluded.

Inclusion Criteria

I am female.

You are proficient in both verbal and written English.

I've had at least 2 yeast or BV infections in the last year that needed treatment.

Exclusion Criteria

I currently have a urinary tract infection (UTI).

Pregnant or trying to become pregnant

I have gone through menopause.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

1 visit (in-person)

Baseline Assessment

Assessment and classification of patients' vaginal microbiome prior to receipt of the intervention

1 week

Self-collection at home

Treatment

Participants use Phexxi twice per week for 30 days, with self-collection of samples and diary keeping

4 weeks

Self-collection at home

Post-Treatment Assessment

NextGen analysis and survey to assess changes in vaginal microbiome and symptoms immediately after intervention

1 week

Self-collection at home

Follow-up

Participants are monitored for changes in vaginal microbiome and symptoms 30 days post-intervention

4 weeks

Self-collection at home

What Are the Treatments Tested in This Trial?

Interventions

• Phexxi

Trial Overview

The study tests if Phexxi (an intravaginal contraceptive gel) alters the vaginal microbiome by promoting lactic acid-producing lactobacilli growth. This could potentially help prevent recurrent bacterial vaginosis and yeast infections.

How Is the Trial Designed?

Group I: Study group Experimental Treatment 1 Intervention

This is a single-arm study. all participants are assigned to this arm. all study participants will receive Phexxi, the study drug. 8 pre-filled vaginal inserters with vaginal gel, Phexxi, will be provided to each of the participants with verbal and written instructions for application. Patients will be instructed to use Phexxi twice per week, on the same days every week.

Phexxi is already approved in United States for the following indications:

Approved in United States as Phexxi for:

• Birth Control

Who Is Running the Clinical Trial?

Queen's Medical Center

Lead Sponsor

Trials

24

Recruited

4,900+

University of Hawaii Foundation

Collaborator

Trials

2

Recruited

60+

Published Research Related to This Trial

Intravaginal tablets made from hydrophilic methylcellulose and containing lactic acid and chitosan can effectively form a gel that adheres to the vaginal mucosa, providing a durable dosage form for treatment.

By adjusting the ratio of lactic acid to chitosan, these tablets can maintain a physiological pH range while also having the ability to neutralize excess alkalinity during severe vaginal infections, enhancing their therapeutic potential.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Studies on gynaecological hydrophilic lactic acid preparations, Part 7: use of chitosan as lactic acid carrier in intravaginal tablets (globuli vaginales). Małolepsza-Jarmołowska, K.[2013]

In a study of 56 women with a lactobacillus-dominated vaginal microbiota, the average pH of cervicovaginal fluid was found to be 3.5, indicating a more acidic environment than previously reported, which enhances the protective effects against infections.

The concentration of lactic acid was significantly higher than earlier studies suggested, making it a more potent microbicide, thus highlighting the importance of lactobacilli in providing greater protection against reproductive tract infections than previously understood.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Vaginal pH and microbicidal lactic acid when lactobacilli dominate the microbiota. O'Hanlon, DE., Moench, TR., Cone, RA.[2023]

In a study of 42 women with recurrent bacterial vaginosis (BV), treatment with an acid lactate gel significantly reduced BV symptoms, with 88% of women showing clinical improvement compared to only 10% in the placebo group.

The lactate gel also effectively restored normal vaginal flora, with 83% of women in the treatment group reestablishing healthy lactobacilli levels, while only 16% in the placebo group did so, and the treatment was found to be free of side effects.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Bacterial vaginosis and the effect of intermittent prophylactic treatment with an acid lactate gel. Andersch, B., Lindell, D., Dahlén, I., et al.[2018]

High performance ion exchange chromatography revealed a significant presence of caproic acid in the vaginal fluid of a woman with persistent foul odor, indicating a potential link to her symptoms.

After treatment with metronidazole, the caproic acid levels decreased and were replaced by lactic acid, suggesting that this method could be effective for diagnosing and monitoring other vaginal infections.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Evaluation of vaginal malodor and efficacy of treatment by high performance ion exchange chromatography. Stanek, R., Glover, DD., Mya, S., et al.[2016]

In a study involving 919 women with vulvo-vaginal infections, the adjuvant therapy of lactic acid+lactoserum provided significant symptomatic relief, with 80.1% of patients reporting reduced malodour and 78.5% experiencing less itching by the fourth day of use.

The treatment was well-tolerated, with 91.3% of patients finding it gentle on the skin and no adverse events reported, indicating a high level of safety and patient satisfaction (88.6%) with the therapy.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Lactacyd FH as an adjuvant therapy for vulvovaginal infections in Pakistani women: FRESH study, a satisfaction survey. Eusaph, AZ., Nighat, R., Arshad, A.[2017]

The lactic acid-based feminine hygiene solution was tested on 40 women over 8 weeks, showing no significant changes in vaginal pH or flora, indicating its safety and tolerability.

Despite two cases of candidiasis during the trial, the vaginal flora returned to normal by the end of the study, suggesting that the product does not disrupt healthy vaginal microbiota.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Study of a new lactic acid and pH 5.2 lactoserum emulsion for feminine hygiene. Results of a clinical study]. Jacquet, A., Roussilhes, R., Anoufa, S., et al.[2013]

The study developed hydrophilic intravaginal tablets made from methylcellulose, lactic acid, and chitosan that swell and form a gel at physiological pH, which could provide a durable dosage form for vaginal applications.

By adjusting the ratio of lactic acid to chitosan, the tablets can create gels that not only maintain an optimal pH for vaginal health but also have the potential to neutralize excess alkalinity during severe vaginal infections.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Studies on gynecological hydrophilic lactic acid preparations. Part 8: use of chitosan as lactic acid carrier in intravaginal tablets. Małolepsza-Jarmołowska, K.[2013]

Citations

1.

aafp.org

aafp.org/pubs/afp/issues/2021/0515/p628.html

Lactic Acid, Citric Acid, and Potassium Bitartrate (Phexxi) ...

The most common adverse effects of Phexxi are localized to the vagina and include burning sensation (18%), itching (14.5%), vulvovaginal mycotic ...

2.

cdn.clinicaltrials.gov

cdn.clinicaltrials.gov/large-docs/13/NCT05753813/Prot_000.pdf

Exploring the effects of an intravaginal lactic acid gel on the ...

One study shows that the use of lactic acid gel as a treatment for bacterial vaginosis is comparable, but not superior to, the use of metronidazole8,9,10.

3.

accessdata.fda.gov

accessdata.fda.gov/drugsatfda_docs/nda/2020/208352Orig1s000MultidisciplineR.pdf

208352Orig1s000 - accessdata.fda.gov

The established name of this gel is Lactic Acid, Citric Acid, and Potassium Bitartrate Vaginal Gel,. 1.76 %/1 %/0.4%. In June 2004, Center ...

4.

reference.medscape.com

reference.medscape.com/drug/phexx-lactic-acid-citric-acid-potassium-bitartrate-vaginal-4000052

lactic acid/citric acid/potassium bitartrate vaginal (Rx)

1-10% · Local discomfort in male partners (9.8%) · Vulvovaginal mycotic infection (9.1%) · Urinary tract infection (UTI) (9%) · Vulvovaginal discomfort (9%) ...

5.

tandfonline.com

tandfonline.com/doi/full/10.1080/13625187.2025.2540397

Exploring the dual potential of Novel vaginal contraceptive ...

In conclusion, Lactic Acid, Citric Acid, and Potassium Bitartrate Contraceptive Vaginal Gel (Phexxi®) offers a promising, hormone-free contraceptive option with ...

6.

accessdata.fda.gov

accessdata.fda.gov/drugsatfda_docs/label/2020/208352s000lbl.pdf

Phexxi - accessdata.fda.gov

Systemic exposures of lactic acid, citric acid, and potassium bitartrate following vaginal administration of PHEXXI are not expected to lead to safety concerns.

7.

phexxi.com

phexxi.com/aboutphexxi

About The Hormone Free Birth Control Gel

IMPORTANT safety information​​ Phexxi does not protect against any sexually transmitted infections, including HIV. Avoid using Phexxi with a vaginal ring. Avoid ...

8.

phexxi.com

phexxi.com/hubfs/PhexxiUSPI.pdf

HIGHLIGHTS OF PRESCRIBING INFORMATION These ...

Systemic exposures of lactic acid, citric acid, and potassium bitartrate following vaginal administration of PHEXXI are not expected to lead to safety concerns.

9.

accessdata.fda.gov

accessdata.fda.gov/drugsatfda_docs/label/2025/208352s005lbl.pdf

PHEXX® (lactic acid, citric acid, and potassium bitartrate ...

Among 2804 subjects who received PHEXX in Studies 1 and 2, 0.36% (n=10) reported adverse reactions of cystitis, pyelonephritis, or other upper urinary tract ...