Antibiotics treating community-acquired infections can be developed in both intravenous and oral formulations. Having both dosing formulations enables enrollment of moderately to seriously ill patients who require intravenous antibiotics and allows step-down therapy with the oral formulation. In the setting of highly prevalent bacterial resistance for serious infections and the need for urgent empiric therapy prior to culture and sensitivity results, older generic antibiotics can no longer be selected over newer, potent, and more expensive antibiotics.
Unlike other therapeutic classes, for example the statins, it is inappropriate to “try and fail” with older antibiotics. Resistant pathogens can kill the patient. Using the best antibiotic as the first choice in serious infections may be the only choice for that patient. After several years of use, safety can be proven in the setting of broad exposure, Phase IV studies can be conducted, and the oral formulations could become available for out-patient use.
The regulatory and clinical environment has evolved over the last decade with many ramifications. Today, clinical trial guidelines have focused on quantitative, highly measurable primary endpoints that occur early in the course of therapy. New antibiotics must be tested in moderate-to-severe infections, which are usually treated in the hospital. This means that oral-only therapies that are best positioned for treating community infections must take a different approach for seeking regulatory approval.
Pharmaceutical companies that can discover innovative antibiotics, particularly those that can be administered both intravenously and orally, are more likely to succeed through the regulatory process and may have the opportunity to be positioned to treat community infections.