SpeeDx Pty Ltd, Sydney, Australia, has announced that FDA has granted a breakthrough device designation for the company’s ResistancePlusGC test, expediting the path toward FDA clearance.

ResistancePlusGC is the first commercially available molecular test to provide ciprofloxacin susceptibility and resistance information for use in treating the sexually transmitted infection Neisseria gonorrhoeae. The testdetects both the sexually transmitted infection N. gonorrhoeae and sequences in the gyrA gene of the bacterium associated with susceptibility or resistance to ciprofloxacin, a previously used front-line antibiotic treatment. The test is CE marked and cleared by Australia’s Therapeutic Goods Administration, making it available for use across Europe, Australia, and New Zealand.

Results from the test can be used to guide treatment decisions for gonorrhea infections, giving doctors and patients the option of using ciprofloxacin instead of ceftriaxone, one of the last remaining antibiotics available for multidrug-resistant infections.

“There is an urgent need for better diagnostics to address the problem of drug-resistant gonorrhea in the United States,” says Jeffrey Klausner, MD, professor of medicine and public health at the University of California, Los Angeles. “Drug-resistant gonorrhea is an urgent public health problem.”


Colin Denver, SpeeDx.

“We are very pleased that FDA has recognized ResistancePlus GC as an important tool for the ongoing arms race against gonorrhea and rising antibiotic resistance,” says Colin Denver, CEO of SpeeDx. “The results from our tests empower clinicians to make better informed treatment decisions, and we are passionate about the responsible use and stewardship of antibiotics to achieve the best possible patient outcomes.”

Ceftriaxone, a painful intramuscular injection, is the current front-line treatment for gonorrhea. However, resistance to the drug has already been reported in Europe and Australia, and experts are concerned that we may quickly run out of treatment options altogether.1–3 Recent surveillance data indicate that in some regions up to 7 out of 10 infections could be effectively treated with a single, more convenient oral dose of ciprofloxacin if the susceptibility status of the infection is established prior to prescribing.4–6 The British Association of Sexual Health and HIV has recognized the importance of antibiotic stewardship in its recently updated gonorrhea management guidelines, preferring the use of ciprofloxacin over ceftriaxone if antibiotic susceptibility results are available prior to treatment.7

“SpeeDx tests can help make antibiotic-resistance guided therapy a reality, giving doctors real-time information to make smarter antibiotic treatment choices,” says Klausner.

For further information, visit SpeeDx.


  1. UK case of Neisseria gonorrhoeaewith high-level resistance to azithromycin and resistance to ceftriaxone acquired abroad [Public Health England publications gateway no. 2017893]. Health Protection Report Advanced Access Report. 2018;12(11). Available at: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/694655/hpr1118_mdrgc.pdf. Accessed August 5, 2019.
  1. Australia Department of Health Media Statement, April 17, 2018.
  1. Unemo M, Jensen JS. Antimicrobial-resistant sexually transmitted infections: gonorrhea and Mycoplasma genitalium. Nat Rev Urol. 2017;14(3):139–152; doi:10.1038/nrurol.2016.268.
  1. Eyre DW, Town K, Street T, et al. Detection in the United Kingdom of the Neisseria gonorrhoeae FC428 clone, with ceftriaxone resistance and intermediate resistance to azithromycin, October to December 2018. Euro Surveill. 2019;24(10):1900147; doi: 10.2807/1560-7917.es.2019.24.10.1900147.
  1. Harris SR, Cole MJ, Spiteri G, et al. Public health surveillance of multidrug-resistant clones of Neisseria gonorrhoeaein Europe: a genomic survey. Lancet Infect Dis. 2018;18(7):758–768; doi:10.1016/S1473-3099(18)30225-1.
  1. Lahra MM, Enriquez RP. Australian gonococcal surveillance program annual report, 2015. Commun Dis Intell Q Rep. 2017;41(1):E.
  1. Fifer H, Saunders J, Soni S, Sadiq ST, FitzGerald M. British Association for Sexual Health and HIV National Guideline for the Management of Infection with Neisseria gonorrhoeae (2019). Macclesfield, UK: British Association for Sexual Health and HIV, 2019. Available at: https://pcwhf.co.uk/wp-content/uploads/2019/03/gc-2019.pdf. Accessed August 5, 2019.

Featured image:

 Three-dimensional computer-generated image of drug-resistant Neisseria gonorrhoeae diplococcal bacteria, based on scanning electron microscopic imagery. Illustration by James Archer. CDC Public Health Image Library, ID 16874.