Can fosfomycin be used to treat prostatitis?

From the Guidelines

Fosfomycin should not be considered a first-line treatment option for prostatitis due to limited evidence on its effectiveness for this specific condition. The most recent guidelines for the prevention, diagnosis, and management of urinary tract infections, including prostatitis, do not provide clear recommendations for the use of fosfomycin in treating prostatitis 1. For acute bacterial prostatitis, fluoroquinolones or trimethoprim-sulfamethoxazole are typically preferred initial choices. Fosfomycin may be considered as an alternative therapy in cases where patients have multidrug-resistant organisms or cannot tolerate first-line antibiotics. Some key points to consider when evaluating the use of fosfomycin for prostatitis include:

• The lack of clear recommendations for the duration of treatment for prostatitis, with historical durations ranging from 14 days for acute bacterial prostatitis to 6 weeks or longer for chronic bacterial prostatitis 1.
• The variable penetration of fosfomycin into prostatic tissue, which may limit its effectiveness in treating prostatitis.
• The importance of guiding treatment by culture results when available to ensure the causative organism is susceptible to fosfomycin.
• The potential for off-label use of fosfomycin in prostatitis in some regions, as it is more commonly used for urinary tract infections. Given the limited evidence and potential limitations of fosfomycin in treating prostatitis, it is essential to carefully evaluate the risks and benefits of using this medication for this condition, and to consider alternative treatment options when possible.

From the FDA Drug Label

Fosfomycin is distributed to the kidneys, bladder wall, prostate, and seminal vesicles Fosfomycin has been shown to cross the placental barrier in animals and man Fosfomycin (the active component of fosfomycin tromethamine) has in vitro activity against a broad range of gram-positive and gram-negative aerobic microorganisms which are associated with uncomplicated urinary tract infections

Fosfomycin can be used to treat prostatitis because it is distributed to the prostate and has in vitro activity against a broad range of microorganisms associated with urinary tract infections 2.

From the Research

Fosfomycin for Prostatitis Treatment

• Fosfomycin has been evaluated as a treatment option for bacterial prostatitis due to its favorable pharmacokinetic profile and activity against multidrug-resistant (MDR) bacteria 3, 4, 5.
• The antibiotic has shown potent in vitro activity against various antimicrobial-resistant Escherichia coli genotypes/phenotypes, including ciprofloxacin-resistant, trimethoprim-sulfamethoxazole-resistant, extended-spectrum β-lactamase- (ESBL-) producing, and MDR isolates 5.
• Clinical cure rates for fosfomycin in treating bacterial prostatitis caused by antimicrobial-resistant E. coli have ranged from 50 to 77%, with microbiological eradication rates of >50% 5.

Efficacy and Safety

• Oral fosfomycin has been found to be effective in achieving clinical and microbiological cure in patients with acute and chronic bacterial prostatitis, including those with MDR Enterobacterales 4, 6, 7.
• The treatment has been well-tolerated, with minimal adverse effects reported, such as diarrhea and digestive disorders 6, 7.
• Fosfomycin may represent a valid therapeutic option for treating susceptible germs commonly causing prostatitis, including E. coli and other Enterobacterales, even as a first-line regimen in specific clinical settings 3.

Treatment Regimens

• Various treatment regimens have been used, including oral fosfomycin 3 g every 24-48 hours, with treatment durations ranging from 2-12 weeks 5, 6, 7.
• The choice of treatment regimen may depend on the specific clinical setting, patient characteristics, and resistance patterns of the causative organism 3, 4.