Preferred fluoroquinolone against m. leprae is -

Ans. is 'a' i.e., Ofloxacin Drugs acting on M. leprae* Established agents used to treat leprosy include dapsone (50-100 mg/d), clofazimine (50-100 mg/d, 100 mg three times weekly, or 300 mg monthly), and rifampin (600 mg daily or monthly. Of these drugs, only rifampin is bactericidal.* The sulfones (folate antagonists), the foremost of which is dapsone, were the first antimicrobial agents found to be effective for the treatment of leprosy and are still the mainstay of therapy.* Other antimicrobial agents active against M. leprae in animal models and at the usual daily doses used in clinical trials include ethionamide/prothionamide; the aminoglycosides streptomycin, kanamycin, and amikacin (but not gentamicin or tobramycin); minocycline; clarithromycin; and several fluoroquinolones, particularly preferred is ofloxacin.* Next to rifampin, minocycline, clarithromycin, and ofloxacin appear to be most bactericidal for M. leprae, but these drugs have not been used extensively in leprosy control programs. Most recently, rifapentine and moxifloxacin have been found to be especially potent against M. leprae in mice. In a clinical trial in lepromatous leprosy, moxifloxacin was profoundly bactericidal, matched in potency only by rifampin.