Serum Pharmacokinetics and Bone Penetration of Novel Broad-Spectrum Anti-MRSA Agent Levonadifloxacin in Wistar Rats.

Objectives: Levonadifloxacin (IV) and alalevonadifloxacin (oral) are novel broad-spectrum anti-methicillin-resistant Staphylococcus aureus (S. aureus) agents based on novel benzoquinolizine core. Both are recently approved in India for the treatment of acute bacterial skin and skin structure infections, including diabetic foot infections and concurrent bacteremia. The present investigation reports the findings from preclinical pharmacokinetic (PK) studies that support the development of levonadifloxacin as a treatment option for bone and joint infections (BJIs). Methods: PK profiles of levonadifloxacin were obtained in serum, and/or various anatomical segments of femoral bone such as whole bone (WB), hard bone (HB), and bone marrow (BM) following subcutaneous administration of levonadifloxacin single doses at 50, 100, 200, and 400 mg/kg, as well as multiple doses at 200 mg/kg (BID (two times a day), 6 hours apart) for 5 days in Wistar rats. Results: The distribution of levonadifloxacin in bone was rapid, and the extent of distribution (B/S ratio; bone-to-serum area under the concentration-time curve ratio) was nearly comparable across bone segments. In single-dosage PK studies, the mean B/S ratio in WB, HB, and BM was 0.40, 0.33, and 0.34, respectively; however, in 5 days' repeated dose studies, it increased to 1.01, 1.14, and 0.61, respectively. Conclusions: On the basis of bone PK data in Wistar rat and ever-growing clinical experience in terms of safety and efficacy, levonadifloxacin has the potential to offer a well-differentiated therapy for the treatment of BJIs.