Efficacy of tREating aSymptomatic infEctions To resTore fERtility: The RESETTER Study

Couples will submit semen, penile and vaginal swab samples for analysis; A portion of semen samples will undergo routine analysis as per World Health Organisation (WHO) guidelines, and the remaining semen will be utilised for DNA extraction alongside penile and vaginal swab samples. Semen, penile and vaginal swabs will undergo qPCR analysis for the presence of Genital Mycoplasmas, and where one or more are identified in at least one partner, couples will be treated with either doxycycline (M. hominis and U. urealyticum) and/or azithromycin or moxifloxacin (M. genitalium) as per standard treatment guidelines. Moxifloxacin will only be used in participants where antibiotic resistance markers are identified in M. genitalium based on the four 23S rRNA mutation targets (A2058T, A2058C, A2058G, A2059G) included in the SpeeDx MG ResistancePlus assay. Lactobacillus and Bifidobacterium spp. will be quantified in vaginal swabs. Women will receive a vaginal Lactobacillus sp. probiotic for five weeks post-treatment and then both partners will provide follow-up semen, penile and vaginal swab samples for repeat analysis. 1) Azithromycin dihdyrate, 250mg tablets (Azithromycin, Sandoz) - AUST R 58797. This is a broad-spectrum antibiotic of the macrolide class. In this trial it will be used to treat Mycoplasma genitalium colonisation without macrolide resistance mutations. Azithromycin is the current gold standard for treatment of uncomplicated macrolide sensitive M. genitalium infections, with the 2021 European guidelines reporting a cure rate of 85-95%. Azithromycin is sold in a 500mg tablet form, but in this trial pharmacies will dispense it as 500mg tablets with defined break-points (already present from the manufacturer) and instruct participants on how to break the tablets in half to obtain 250mg doses. An initial dose of 500mg, followed by 250mg daily for a further four days is the recommended dosing regimen. 2) Doxycycline, 100mg tablets (Doxycycline, Sandoz) - AUST R 66302. Doxycycline is a broad-spectrum antibiotic of the tetracycline class that is effective against Gram positive and negative pathogens, as well as Genital Mycoplasmas, Spirochaetes and some parasites. In this trial it will be used to treat colonisation by Ureaplasma urealyticum and Mycoplasma hominis; it is well-recognised as being effective against both of these organisms, with low-levels of resistance documented. The dosing strategy to be used in this trial will mirror that used in a similar trial by Ahmadi et al. 2017, consisting of 100mg twice daily for seven days. 3) Moxifloxacin, 400mg tablets (Moxifloxacin APO) – AUST R 309824. Moxifloxacin is a broad-spectrum antibiotic of the quinolone class that is effective against Gram positive and negative pathogens, as well as Genital Mycoplasmas. In this trial it will be used to treat colonisation by macrolide-resistant M. genitalium. The dosing strategy to be used is as per the European Guidelines, consisting of 400mg daily for seven days. 4) Lactobacillus crispatus (2 billion CFU), Lactobacillus gasseri (2 billion CFU), Lactobacillus rhamnosus (1.25 billion CFU), Lactobacillus reuteri (1.25 billion CFU) (V-Spot, CGS Pharma/Amelia Bio). V-spot is a commercial vaginal probiotic preparation that is TGA-approved. It contains a mixture of Lactobacillus sp., including L. crispatus, L. gasseri, L. rhamnosus and L. reuteri. In the current trial it is being administered post-antibiotic treatment via vaginal application (insertion of a vaginal pessary) to help restore the vaginal microbiota to an optimal state. Dosing strategy is once daily for six days, followed by weekly administration for four weeks (five weeks treatment in total). Treatment compliance will be recorded using a medicine accountability log that is included with the treatment pack and will be returned at the same time follow-up samples are collected.