Lactic acid, citric acid, and potassium bitartrate non-hormonal prescription vaginal pH modulator (VPM) gel for the prevention of pregnancy

ABSTRACT

Introduction

A non-hormonal prescription vaginal pH modulator (VPM) gel (Phexxi®), with active ingredients lactic acid, citric acid and potassium bitartrate, has recently been approved for prevention of pregnancy in the United States. The objective of this review is to compile the evidence available from published preclinical and clinical trials to support its use.

Areas covered

PubMed was searched for published literature on VPM gel. Two Phase III trials were found on clinicaltrials.gov database. The results demonstrated that VPM gel is safe, with minimal side effects, and effective (cumulative 6–7 cycle pregnancy rate of 4.1–13.65%, (Pearl Index 27.5) as a contraceptive. Microbicidal effects suggest potential for the prevention of sexually transmitted infections (STIs); currently a Phase III clinical trial is being conducted to evaluate prevention of chlamydia and gonorrhea.

Expert opinion

Non-hormonal reversible contraceptive options have been limited to the highly effective copper-releasing intrauterine device that requires insertion by a trained clinician, and less effective coitally associated barrier and spermicide options which are typically available over-the-counter. Spermicides, which improve efficacy of barrier devices, may increase the risk of HIV/STIs. VPM gel provides a new safe, effective non-hormonal contraceptive option, with potential for prevention of STIs.

KEYWORDS:

• Citric acid
• lactic acid
• non-hormonal contraception
• potassium bitartrate
• topical vaginal contraceptive
• vaginal pH modulator (VPM) gel

Article highlights

• A vaginal pH modulator gel (VPM), composed of lactic acid, citric acid and potassium bitartrate, was recently approved for the indication of prevention of pregnancy by the FDA.

• Phase III trials have demonstrated VPM gel’s safety and efficacy as a contraceptive, with a cumulative 6-7-cycle pregnancy rate between 4.1% and 13.65% and a Pearl Index of 27.5.

• There have been multiple Phase I studies investigating VPM’s effect on the prevention of sexually transmitted infections (STIs), however more research is needed to make definitive recommendations.

• A Phase IIb/III study assessing VPM’s effect on the prevention of chlamydia and gonorrhea has resulted in the FDA granting it both the Fast Track and Qualified Infectious Disease Product (QIDP) Designation for the prevention of both infections in women.

Declaration of interest

KL Vincent has collaborated with Mucommune, Inc. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Information resources

Detailed information can be obtained from the following sources:

• https://www.phexxi.com

• https://www.accessdata.fda.gov/drugsatfda_docs/label/2022/208352s002lbl.pdf

• https://hcp-phexxi.com/themes/custom/phexxiHCP/dist/pdf/PhexxiUSPI.pdf#page=1

Reviewer disclosures

A reviewer on this manuscript has disclosed being an investigator on the two clinical trials for this product and writing summary articles on the topic. Peer reviewers on this manuscript have no other relevant financial relationships or otherwise to disclose. Evofem Biosciences provided a scientific accuracy review at the request of the journal editor.

Additional information

Funding

This paper was not funded.