Gemifloxacin clinical studies

# CLINICAL STUDIES

# Acute Bacterial Exacerbation of Chronic Bronchitis (ABECB)
FACTIVE (320 mg once daily for 5 days) was evaluated for the treatment of acute bacterial exacerbation of chronic bronchitis in three pivotal double-blind, randomized, actively-controlled clinical trials (studies 068, 070, and 212). The primary efficacy parameter in these studies was the clinical response at follow-up (day 13 to 24). The results of the clinical response at follow-up for the principal ABECB studies demonstrate that FACTIVE 320 mg PO once daily for 5 days was at least as good as the comparators given for 7 days. The results are shown in Table 6 below.

## Community Acquired Pneumonia (CAP)
5 Day Treatment Regimen
To evaluate the safety and efficacy of a 5-day course of FACTIVE, 510 outpatient and hospitalized adults with clinically and radiologically determined mild to moderate community-acquired pneumonia were clinically evaluated in a double-blind, randomized, prospective, multicenter study comparing FACTIVE 320 mg for five days to FACTIVE 320 mg for seven days (Study OP-634-001).
Clinical success rates in the clinically evaluable population were 95.0% in the 5 day group and 92.1% in the 7 day group.
The microbiological efficacy of the 5-day regimen was documented for pathogens listed in Table 8 below.

## 7 Day Treatment Regimen
Previous clinical studies evaluated the efficacy of FACTIVE in a 7-day treatment of CAP in adults. This clinical program consisted of three double-blind, randomized, actively-controlled clinical studies (studies 011, 012, and 049) and one open-label, actively-controlled study (study 185). In addition, two uncontrolled studies (studies 061 and 287) were conducted. Three of the studies, controlled study 011 and the uncontrolled studies, had a fixed 7-day duration of treatment for FACTIVE. Controlled study 011 compared a 7-day course of FACTIVE with a 10-day treatment course of amoxicillin/clavulanate (1g/125 mg TID) and clinical success rates were similar between treatment arms. The results of comparative studies 049, 185, and 012 were supportive although treatment duration could have been 7 to 14 days. The results of the clinical studies with a fixed 7-day duration of FACTIVE are shown in Table 9.
The combined bacterial eradication rates for patients treated with a fixed 7-day treatment regimen of FACTIVE are shown in Table 10.
7 Day Treatment Regimen of Community-Acquired Pneumonia Due to Multi-Drug Resistant Streptococcus pneumoniae (MDRSP)
FACTIVE was also effective in the treatment of CAP due to multi-drug resistant Streptococcus pneumoniae (MDRSP*). Of 35 patients with MDRSP treated for 7 days, 29 (82.9%) achieved clinical and bacteriological success at follow-up. The clinical and bacteriological success for the 35 patients with MDRSP isolates are shown in Table 11.
- MDRSP: multi-drug resistant Streptococcus pneumoniae, includes isolates previously known as PRSP (penicillin-resistant Streptococcus pneumoniae), and are strains resistant to two or more of the following antibiotics: penicillin (MIC 2 g/mL), 2nd generation cephalosporins (e.g., cefuroxime), macrolides, tetracyclines and trimethoprim/sulfamethoxazole.
Not all isolates were resistant to all antimicrobial classes tested. Success and eradication rates are summarized in Table 12 below.

## Clinical Safety Study of Rash
To further characterize gemifloxacin-associated rash, which in early clinical studies appeared to be associated with age less than 40 and female gender, a clinical pharmacology study was conducted. The study enrolled 1,011 healthy female volunteers less than 40 years of age. Subjects were randomized in a 5:1 ratio to receive either FACTIVE 320 mg PO daily (819 subjects) or ciprofloxacin 500 mg PO twice daily for 10 days (164 subjects). This study was designed to enroll subjects at a high risk for rash (women 60% of the body surface area was involved; the characteristics of the rash were otherwise indistinguishable from those subjects reporting a mild rash. The histopathology was consistent with the clinical observation of uncomplicated exanthematous morbilliform eruption. Approximately 11% of the rashes were described as being urticaria-like. There were no documented cases of hypersensitivity syndrome or findings suggestive of angioedema or other serious cutaneous reactions.
The majority of rashes (81.9%) occurred on days 8 through 10 of the planned 10 day course of FACTIVE; 2.7% of rash events occurred within one day of the start of dosing. The median duration of rash was 6 days. The rash resolved without treatment in the majority of subjects. Approximately 19% received antihistamines and 5% received steroids, although the therapeutic benefit of these therapies is uncertain.
In the second part of this study after a 4 to 6 week wash out period, subjects developing a rash on FACTIVE were treated with ciprofloxacin (n=136) or placebo (n=50); 5.9% developed rash when treated with ciprofloxacin and 2.0% developed rash when treated with placebo. The cross sensitization rate to other fluoroquinolones was not evaluated in this clinical study. There was no evidence of sub-clinical sensitization to FACTIVE on a second exposure (i.e., subjects who had not developed a rash to FACTIVE in the first part of the study were not at higher risk of developing a rash to FACTIVE with a second exposure).
There was no relationship between the incidence of rash and systemic exposure (Cmax and AUC) to either gemifloxacin or its major metabolite, N-acetyl gemifloxacin.