SpeeDx Pty Ltd, Sydney, has signed an agreement with Thermo Fisher Scientific, Waltham, Mass, in support of SpeeDx’s plan to submit its ResistancePlus MG test for FDA clearance.

Under the terms of the agreement, SpeeDx will submit the test to FDA upon successful validation of its use on the Applied Biosystems 7500 Fast Dx real-time polymerase chain reaction (PCR) system. The ResistancePlus MG test is designed to detect M. genitalium, a rapidly growing sexually transmitted infection (STI) that has developed significant resistance to first-line antibiotic treatment and threatens to become a potential ‘superbug.’

The ResistancePlus MG test identifies both M. genitalium and mutations in the 23S rRNA gene of the bacterium that have been shown to confer resistance to azithromycin, a commonly prescribed macrolide-based antibiotic. The test has previously received the CE mark and accreditation by the Australian Therapeutic Goods Administration, and is now marketed across Europe, Australia, and New Zealand.

Colin Denver, SpeeDx.

Colin Denver, SpeeDx.

“We developed our diagnostic test to answer the immediate need for detection and resistance screening for this difficult-to-manage STI,” says Colin Denver, CEO of SpeeDx. “With their reputation for scientific excellence, we are very pleased to partner with Thermo Fisher to bring this test to the US market. Applied Biosystems qPCR instrumentation has a long-standing reputation for quality and a wide install base across the region.”

M. genitalium can cause symptoms such as urethritis, cervicitis, endometritis, and pelvic inflammatory disease. In recent studies, it has been found to have a higher prevalence than gonorrhea. Like gonorrhea, M. genitalium is also evolving into a so-called STI superbug that is resistant to many antibiotic treatments, leading to difficult-to-treat infections and threatening global public health.

Macrolide antibiotics, specifically azithromycin, are the first-line treatment for the rapidly growing problem of M. genitalium STIs, but resistance to these antibiotics has increased up to 40% in several countries.1–3 This development led the authors of the European guideline on M. genitalium infections last year to recommend complementing the molecular detection of M. genitalium with an assay capable of detecting macrolide resistance-associated mutations.4

There is currently no FDA-cleared molecular diagnostic test for the detection of M. genitalium in the United States.

Kim Kelderman, Thermo Fisher Scientific.

Kim Kelderman, Thermo Fisher Scientific.

“We are proud to be partnering with SpeeDx to enable them to bring their diagnostic test to the US market,” says Kim Kelderman, vice president and general manager of genetic analysis at Thermo Fisher Scientific. “We are committed to working with diagnostic partners around the world who share our vision of driving better health outcomes by using precision medicine.”

For more information, visit SpeeDx or Thermo Fisher Scientific.


  1. Salado-Rasmussen K, Jensen JS. Mycoplasma genitalium testing pattern and macrolide resistance: a Danish nationwide retrospective survey. Clin Infect Dis. 2014;59(1):24–30; doi: 10.1093/cid/ciu217.
  1. Tagg KA, Jeoffreys NJ, Couldwell DL, et al. Fluoroquinolone and macrolide resistance-associated mutations in Mycoplasma genitalium. J Clin Microbiol. 2013;51(7):2245–2249; doi: 1128/JCM.00495-13.
  1. Getman D, Jiang A, O’Donnell M, et al. 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: 1128/JCM.01053-16.
  1. Jensen JS, Cusini M, Gomberg M, et al. 2016 European guideline on Mycoplasma genitalium J Eur Acad Dermatol Venereol. 2016;30(10):1650–1656; doi: 10.1111/jdv.13849.