New AntiBiotic Treatment Options for Uncomplicated Anogenital GOnorrhoea

Inclusion criteria main study * 18 years or older * Anorectal, cervical/vaginal or urethral Ng infection, diagnosed by the following: * Ng-positive Gram-stained smear (intracellular Gram-negative diplococci and leukocytes) and/or * Positive for Ng by nucleic acid amplification test (NAAT) (Aptima Combo 2) and/or * Positive for Ng by culture * Provide samples from the included infection site for NAAT and direct culture immediately before treatment * Willing to abstain from anal, vaginal and oral sex until the test of cure (TOC)-visit, or use condoms during sex * Willing and able to return for a TOC-visit 7-14 days after treatment * Provide informed consent * Accept intramuscular injections Exclusion criteria main study Pre-randomisation: * Suspicion of a complicated Ng infection based on signs and/or symptoms indicating pelvic inflammatory disease (PID), epididymitis, prostatitis or gonococcal arthritis\* * Another (sexually transmitted) infection or a suspicion of another infection for which systemic antimicrobial therapy is indicated * Pregnancy, having a wish to become pregnant or breastfeeding (tested at inclusion visit) * Not able to read/understand Dutch or English * HIV infection if: * Newly diagnosed HIV infection (upon the inclusion visit) and/or * CD4+ cell-count \<200 cells/μL (as reported by the patient) * Known allergy or adverse reactions to ceftriaxone, ertapenemor gentamicin * Known renal impairment (based on estimated GFR using Cockroft and Gault formula using serum creatinin measured with a point-of-care (POC) test; cut off value renal impairment eGFR ≤ 50 ml/min) * Known liver cirrhosis (based on history) * Known congestive heart failure (based on history) * Known myasthenia gravis * Known hearing loss or balance disorder, confirmed by an ear-nose-throat (ENT)-doctor or for which an ENT doctor has been consulted and a diagnostic process is still in progress (based on history) * Concurrent use of any of the following medication: * systemic antibacterial antimicrobials other than nitrofurantoin or metronidazole * systemic immunosuppressive drugs * systemic valproic acid * Use of any antimicrobial therapy other than nitrofurantoin or metronidazole in the two weeks prior to study enrollment (based on history) * Previous enrollment in the study * Concurrent participation in other non-observational medical research\* * Unlikely to adhere to the study protocol Post-randomisation: Exclusion of participants from the modified intention to treat analysis (mITT): * Negative result of Ng NAAT of sample collected on T0 (the day of treatment). This could be the case in the following situations: 1. Negative NAAT in spite of positive gram stain. 2. Positive NAAT on pre-study visit but spontaneous clearance of the infection in the time period between first test and return visit for treatment (=study inclusion visit). A novel sample for NAAT will be collected on the study inclusion visit just before administration of treatment; if these results are Ng-negative a participant will be excluded of mITT. * Loss to follow-up, i.e. no study visit TOC 7-14 days after treatment administration. Exclusion from per protocol analysis (PP): * Exclusion of mITT * Use of non-study related antibiotics after inclusion and prior to TOC visit * Condomless sexual contact with the primary anatomical gonorrhea site involved after inclusion and prior to TOC visit * Other protocol violations Inclusion criteria PK substudy (healthy volunteers): * 18 years or older * Provide informed consent Exclusion criteria PK substudy (healthy volunteers) Pre-randomisation: * Pregnancy, having a wish to become pregnant or breastfeeding (tested at inclusion visit) * Not able to read/understand Dutch or English * Known allergy or adverse reactions to ceftriaxone, ertapenem, or fosfomycin. * Known renal impairment (based on estimated GFR using Cockroft and Gault formula using serum creatinin measured with a point-of-care (POC) test; cut off value renal impairment eGFR ≤ 50 ml/min) * Known liver cirrhosis (based on history) * Concurrent use of any of the following medication: * systemic valproic acid * systemic metoclopramide * Use of any systemic antimicrobial therapy other than nitrofurantoin or metronidazole in the two weeks prior to study enrollment (based on history) * Concurrent participation in other non-observational medical research (apart from NABOGO RCT) * Unlikely to adhere to the study