The finding of the present study showed a lower rate of H. pylori eradication in the BPAL-7 regimen compared to the BPAL-10 regimen among patients with dyspepsia and H. pylori infection. Both BPAL-7 and PBAL-10 regimens were well-tolerated and had acceptable patient compliance.
Recent guidelines suggest the eradication rate of triple therapy with a PPI, amoxicillin or metronidazole, and clarithromycin as first-line regimens have decreased, particularly due to an increase in microbial resistance to clarithromycin [1]. Moreover, some recommended bismuth-based quadruple therapy regimens also have an eradication rate of less than 80% [31]. Therefore, more effective regimens are needed to eradicate the H. pylori infection.
A body of evidence suggested to using levofloxacin, a new generation fluoroquinolone with in vitro anti-H. pylori activity, as an alternative agent in clarithromycin-resistant cases. Levofloxacin containing triple, quadruple, and sequential regimens have demonstrated a various range of eradication rates [32–34].
A study compared a triple therapy consisting of esomeprazole, levofloxacin (500 mg daily), and amoxicillin with a standard regimen consist of esomeprazole, metronidazole, bismuth, and tetracycline for a period of 14 days. The eradication rate of levofloxacin containing regimen (96.3% ) was higher than the standard regimen (86.0%) in ITT analysis [24].
Gisbert et al. from Spain demonstrated the eradication rate of ranitidine bismuth citrate, levofloxacin, and amoxicillin as first-line triple therapy for H. pylori was 84.4 and ADRs, mainly including diarrhea, were reported in 9.5% of the patients [35]. This group carried out a trial with 1000 patients on the efficacy of omeprazole, levofloxacin, and amoxicillin for ten days. They reported an eradication rate of 73.8% and ADRs of 20%, which most commonly included nausea, metallic taste, and abdominal pain [25]. The dosage of levofloxacin was higher in these studies (500 mg twice a day). In a recent multicenter study conducted by Gisbert et al., 14 days treatment by esomeprazole, amoxicillin, levofloxacin (500 mg daily), and bismuth as a rescue therapy achieved more than 90% of eradiation rate [26]. In another Spanish study, the eradication rate of omeprazole, levofloxacin (500 mg twice a day), and amoxicillin combination for a ten-day period also had about 20% failure rate [36].
A study from Kosovo randomized 105 patients to either seven or ten days levofloxacin-based regimens, including omeprazole, levofloxacin (500 mg daily), and amoxicillin. The eradication rates were 86.2% and 93.6%, respectively. About 5% of patients experienced ADRs, mostly nausea and diarrhea [27].
Several Taiwanese studies evaluated the efficacy of levofloxacin-containing regimens as rescue therapy for the eradication of H. pylori. Kuo et al. reported the eradication rate of esomeprazole, amoxicillin, and levofloxacin (500 mg daily) regimen for seven days is similar to a second line quadruple standard regimens (about 60–70%) [37]. Four years later, the same group published a study comparing a levofloxacin-containing quadruple therapy (esomeprazole, bismuth, tetracycline, and 500 mg of levofloxacin once daily) for ten days with high-dose metronidazole- containing standard quadruple regimen. Based on their findings, eradication rates of about 80% was reached for both regimens [38]. On the other hand, Hsu et al. showed a ten-day quadruple therapy consist of esomeprazole, bismuth, tetracycline, and levofloxacin (500 mg daily) achieved a very high eradication rate (95.8%) at this geographical area. ADRs were detected in 25.0% of patients [39]. In another study, the efficacy of adding bismuth to a levofloxacin-based triple regimen (rabeprazole, bismuth, amoxicillin, and 500 mg of levofloxacin daily) assessed. The results revealed no further significant eradication rat (67.6%), but no more ADRs were noted [40].
According to the results of the present study, the BPAL-7 and the PBAL-10 regimens were not clinically successful in the treatment of H. pylori with an eradication rate of 62.7 % and 49.1 % by ITT analyses, respectively. Both regimens achieved neither cut point of an ideal regimen (eradication rate of > 90 %), nor acceptable eradication rate of Maastricht and other guidelines (> 80 %) [41]. The low efficacy of these regimens is likely related to the regional pattern of bacterial resistance. The results of these regimens are consistent with a previous Iranian study evaluating the efficacy of a 14-day triple therapy, comprised of omeprazole, levofloxacin (500 mg daily), amoxicillin with success rate of 75 % [42]. However, studies conducted in other parts of Iran revealed fluoroquinolone-containing regimens including a 14-day of omeprazole, levofloxacin (250 mg twice a day) and amoxicillin as well as a 14-day of omeprazole, levofloxacin (500 mg twice a day), and amoxicillin as rescue therapies of H. pylori had eradication rate of 90 % and 86.7 %, respectively [43, 44]. Moreover, there are some other Iranian investigations that evaluated the efficacy of levofloxacin-based, sequential therapy in the treatment of H. pylori, and the eradication rate ranged from 70.8% to 85.1 % [45–47].
No relationship was observed between patient demographic characteristics including age, gender, cigarette smoking, and alcohol drinking and the success rate of both BPAL-7 and PBAL-10 regimens. Previous studies have also demonstrated the eradication rate of levofloxacin-containing regimens was not associated with age [45, 47, 44], gender [46, 45, 44], smoking status [48, 45], and education level [45].
Although high efficacy along with compatibility with the pattern of regional bacterial resistance are the main properties of an ideal pharmacological regimen for eradication of H. pylori, tolerability, patient compliance, simplicity, and cost-efficacy should not be neglected [30]. The compliance rates for the BPAL-7 and PBAL-10 regimens were 97.3 % and 99.1 %, respectively. In spite of high compliance rats, ADRs were reported in one-third of patients. The most-reported ADRs were epigastric pain, nausea, vomiting, and bitter taste. Generally, BPAL-7 and PBAL-10 regimens were patient compatible and well-tolerated.
Limitations
The main limitations of the present study are the lack of regional pattern of antibiotic resistance and a local estimate of H. pylori eradication rate as well as the small number of patients in the groups. The absence of pretreatment susceptibility assessment to levofloxacin is another drawback. Moreover, the finding may not be applicable to patients with previous treatment failure and recurrence disease.