Development of antibiotics a good sign

The CDC now estimates that more than 70% of bacteria that cause hospital-acquired infections are resistant to at least one of the drugs most commonly used to treat them. With an antibiotic pipeline that has been quite dry for some time, clinicians continue to worry about how they'll treat patients who develop resistant infections. Given the unrelenting nature of bacteria to mutate in an effort to outsmart even the most powerful antibiotics, creating new anti-infectives will always be required. Here are several drugs, currently under review by the FDA, that may soon offer us a few much-needed options:

Retapamulin's NDA is based on phase III data from 712 patients. The drug was studied in a total of 2,450 patients during clinical trials; however, the results from these studies have not yet been released by GSK. In laboratory studies presented at the 45th Interscience Conference of Antimicrobial Agents and Chemotherapy (ICAAC), the drug showed potency versus common pathogens found in skin infections and, according to GSK, demonstrated a low propensity for development of resistance in target pathogens. In vitro, the drug showed no target-specific cross-resistance to other antibiotics. Retapamulin's unique mechanism of action allows it to inhibit protein synthesis by binding to the 50s subunit of the bacterial ribosome, rendering it inactive.

Faropenem medoxomil is an ester prodrug of faropenem, which allows for improved oral bioavailability and higher systemic concentrations, according to the manufacturers. The NDA submission was based on data from 11 phase III trials in more than 5,000 patients and is seeking approval for the treatment of acute bacterial sinusitis, community-acquired pneumonia, acute exacerbations of chronic bronchitis, and uncomplicated skin and skin structure infections.

Replidyne is also planning to pursue pediatric indications for faropenem medoxomil and has another antibiotic in its pipeline, REP8839, a tRNA synthetase inhibitor that will be used topically to treat methicillin-resistant Staphylococcus aureus (MRSA).

Garenoxacin differs from conventional quinolones in that it lacks a fluorine atom at position 6 of the quinolone skeleton. According to Toyama, the drug has a broad spectrum of activity, especially against resistant strains of gram-positive organisms such as Streptococcus pneumoniae and MRSA. The FDA has granted garenoxacin a 10-month review, which could mean approval in December of this year.