An overview of potential combination therapies with ceftriaxone as a treatment for gonorrhoea

Introduction
Ceftriaxone is the last available single dose therapy for gonorrhea that effectively treats infections at all sites. Over a quarter of isolates are now resistant to ceftriaxone in some countries. The introduction of carefully chosen combination therapy with ceftriaxone could retard the emergence of ceftriaxone resistance.

Areas covered
This review summarizes the findings of a PubMed search on the use of partner antimicrobial that could be used with ceftriaxone to prevent the emergence and spread of ceftriaxone resistance. We review 16 antimicrobials that could be partnered with ceftriaxone in terms of pharmacokinetic and pharmacodynamic compatibilities, activity against ceftriaxone resistant isolates and probability of antimicrobial resistance emerging.

Expert opinion
Of these 16 antimicrobials, we reject antimicrobials such as fosfomycin due to poor clinical efficacy and tigecycline due to its considerably longer half-life which would likely select for tetracycline resistance. The most promising agents for combination with ceftriaxone are zoliflodacin, delafloxacin, sitafloxacin, eravacycline and possibly gepotidacin and gentamicin. Clinical studies should be conducted to evaluate the efficacy of these combinations on the eradication of N. gonorrhoeae and their impact on AMR in N. gonorrhoeae and other bacterial species.