SpeeDx Pty Ltd, Sydney, Australia, has initiated multisite US-based clinical trials for the company’s ResistancePlus MG test, a molecular diagnostic that detects the sexually transmitted infection (STI) Mycoplasma genitalium (MG) along with genetic markers linked to antibiotic resistance. In recent years there has been a global increase in the prevalence of MG, together with strains of the bacterium that exhibit high rates of resistance to the frontline antibiotic treatment, azithromycin.

MG can cause symptoms such as cervicitis, endometritis, pelvic inflammatory disease, and urethritis. In recent studies, it has been found to have a higher prevalence than gonorrhea.1And like gonorrhea, MG is thought to be evolving into a so-called STI superbug resistant to many antibiotic treatments, leading to exceedingly difficult-to-treat infections and threatening global public health. Due to this growing problem of antibiotic resistance, several global guidelines on the management of MG infections recommend complementing the use of molecular testing to detect MG with an assay capable of detecting mutations associated with macrolide resistance.2–4

The SpeeDx ResistancePlus MG test is in use in laboratories across Australia, Europe, New Zealand, and the UK. In the United States, however, there is currently no FDA-cleared, commercially available test for MG. With US clinical trials now beginning at the University of Alabama at Birmingham, Johns Hopkins University, and TriCore Reference Laboratories, SpeeDx is expecting agency clearance of ResistancePlus MG in 2019.

“This test is an exciting new development that will increase the precision of patient care for patients impacted by Mycoplasma genitalium, a common sexually transmitted infection with limited treatment options,” says Maria Trent, MD, MPH, professor of pediatrics and public health at Johns Hopkins University.

Denver

Colin Denver, SpeeDx.

In many countries around the world, resistance to azithromycin, the frontline recommended treatment for M. genitalium infection, has risen to more than 50%.5,6 In a recent peer-reviewed study, the authors recorded an overall cure rate of more than 92% when using resistance-guided therapy with the ResistancePlus MG test—a significant increase compared to previous cure rates below 60%.7

Data from the recent study has already influenced the updating of STI management guidelines in Australia and the UK, with recommendations to assess the resistance status of MG infections in order to guide appropriate treatment.3,4 Using diagnostics to define appropriate treatment decisions results in more-effective use of antibiotics, curtails the use of inappropriate prescribing, and helps preserve the use of key medicines needed to combat the global rise of antimicrobial resistance.

“This is an important new test that has now influenced MG treatment guidelines in Europe, the UK, and Australia,” says Colin Denver, CEO of SpeeDx.2–4 “We are delighted with the progress of our US clinical trial sites and we are excited to be able to offer the test in the US market in the near future.”

References

  1. Miller WC, Ford CA, Morris M, et al. Prevalence of chlamydial and gonococcal infections among young adults in the United States. JAMA. 2004;291(18):2229–2236.
  1. Jensen JS, Cusini M, Gomberg M, Moi H. 2016 European guideline on Mycoplasma genitalium infections. J Eur Acad Dermatol Venereol. 2016;30(10):1650–1656; doi: 10.1111/jdv.13849.
  1. Update to the 2015 BASHH UK National Guideline on the Management of Non-Gonococcal Urethritis. Macclesfield, Cheshire, UK: British Association for Sexual Health and HIV, 2017. Available at: www.bashhguidelines.org/media/1146/ngu-update-05_2017-final.pdf. Accessed November 6, 2018.
  1. Australian STI Management Guidelines for Use in Primary Care: Mycoplasma genitalium. Darlinghurst, NSW, Australia: Australian Sexual Health Alliance, 2018. Available at: www.sti.guidelines.org.au/sexually-transmissible-infections/mycoplasma-genitalium. Accessed November 6, 2018.
  1. Murray GL, Bradshaw CS, Bissessor M, et al. Increasing macrolide and fluoroquinolone resistance in Mycoplasma genitalium. Emerg Infect Dis. 2017;23(5):809–812; doi: 10.3201/eid2305.161745.
  1. Read TRH, Fairley CK, Murray GL, et al. Outcomes of resistance-guided sequential treatment of Mycoplasma genitalium infections: a prospective evaluation. Clin Infect Dis. 2018; Epub ahead of print, June 5, 2018; doi:10.1093/cid/ciy477.
  1. Getman D, Jiang A, O’Donnell M, Cohen S.Mycoplasma genitalium prevalence, coinfection, and macrolide antibiotic resistance frequency in a multicenter clinical study cohort in the United States. J Clin Microbiol. 2016;54(9):2278–2283; doi: 10.1128/jcm.01053-16.

Featured image: The ResistancePlus MG test by SpeeDx.