Mecillinam: a new antibiotic for enteric fever

Area of Science:

• Pharmacology
• Infectious Diseases
• Microbiology

Background:

• Mecillinam is a penicillin-related antibiotic with enhanced activity against Salmonella species, including Salmonella typhi.
• Mecillinam requires parenteral administration, but its ester, pivmecillinam, offers oral absorption for gastrointestinal delivery.

Purpose of the Study:

• To evaluate the efficacy and tolerability of pivmecillinam in patients with typhoid and paratyphoid fevers.
• To assess serum and bile concentrations of mecillinam in treated patients.

Main Methods:

• A clinical study involving nine patients diagnosed with typhoid or paratyphoid fever.
• Treatment administered with pivmecillinam, followed by measurement of serum and bile mecillinam levels.

Main Results:

• Seven out of eight patients with typhoid fever and the patient with paratyphoid fever showed satisfactory clinical responses.
• One patient experienced vomiting, leading to discontinuation of pivmecillinam; no other adverse reactions were reported.
• Achieved serum and bile mecillinam concentrations significantly exceeded the minimum inhibitory concentrations for most Salmonella strains.

Conclusions:

• Pivmecillinam demonstrates significant potential as an effective oral treatment for typhoid fever.
• The antibiotic is well-tolerated, with high drug concentrations achieved in relevant bodily fluids.
• Mecillinam represents a valuable addition to the therapeutic options for Salmonella infections.