Efficacy of chemotherapy and atezolizumab in patients with non-small-cell lung cancer receiving antibiotics and proton pump inhibitors: pooled post hoc analyses of the OAK and POPLAR trials

BACKGROUND

Preclinical data have shown that proton pump inhibitors (PPI) can modulate the microbiome, and single-arm studies suggested that antibiotics (ATB) may decrease the efficacy of immune checkpoint inhibitors (ICI), but randomized controlled trial data are lacking. This pooled analysis evaluated the effect of ATB and PPI on outcome in patients randomized between ICI and chemotherapy.

PATIENTS AND METHODS

This retrospective analysis used pooled data from the phase II POPLAR (NCT01903993) and phase III OAK (NCT02008227) trials, which included 1512 patients with previously treated non-small-cell lung cancer (NSCLC) randomly assigned to receive atezolizumab (n = 757) or docetaxel (n = 755). The main objective of this analysis was to assess the impact of ATB and PPI use on overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 169 (22.3%) patients in the atezolizumab group and 202 (26.8%) in the docetaxel group received ATB, and 234 (30.9%) and 260 (34.4%), respectively, received PPI. Multivariate analysis in all patients revealed that ATB were associated with shorter OS [hazard ratio (HR) 1.20, 95% confidence interval (CI) 1.04-1.39], as was PPI (HR 1.26, 95% CI 1.10-1.44). Within the atezolizumab population, OS was significantly shorter in patients who received ATB (8.5 versus 14.1 months, HR 1.32, 95% CI 1.06-1.63, P = 0.01) or PPI (9.6 versus 14.5 months, HR 1.45, 95% CI 1.20-1.75, P = 0.0001). PPI use was associated with shorter PFS in the atezolizumab population (1.9 versus 2.8 months, HR 1.30, 95% CI 1.10-1.53, P = 0.001). There was no association between ATB and PPI use and PFS or OS within the docetaxel population.

CONCLUSION

In this unplanned analysis from two randomized trials, data suggest that ATB or PPI use in patients with metastatic NSCLC is associated with poor outcome and may influence the efficacy of ICI.

Endodontic Rotary Systems: Comparison between Gentlefile and Pro Taper Universal for removal of Enterococcus faecalis

Background

As a resistant bacterium species in infected root canals, Enterococcus faecalis needs to be removed in any endodontic treatment. So, we aimed to compare the effectiveness of two rotary systems, Gentlefile and Pro Taper Universal, in removing Enterococcus faecalis (E. faecalis) from the infected root canal system.

Material and Methods

Forty single-root premolar teeth were collected and randomly divided into two groups: Gentlefile (n=18) and Pro Taper Universal (n=18). In addition, four teeth were used as a negative control. The root canals were prepared and infected with E. faecalis and incubated for 4 weeks. Samples were obtained from the root canal immediately before and after instrumentation. A reduction in bacteria was determined by the colony count method.

Results

Colony numbers of E. faecalis were significantly different before and after instrumentation in all groups (p<0.001). Furthermore, Gentlefile group illustrated a higher percentage of bacterial reduction (96.1%) compared to Pro Taper Universal group (90%). Accordingly, Gentlefile group was found to be significantly (p<0.001) more effective in decreasing bacterial populations than Pro Taper Universal group.

Conclusions

Although both rotary systems were highly effective in bacterial reduction from root canals, Gentlefile demonstrated better bacterial reduction percentage from root canals than Pro Taper Universal. Key words:Enterococcus faecalis, Gentlefile, Pro Taper Universal, Rotary systems.

Prevalence of Porphyromonas gingivalis and Bacteroides forsythus in chronic periodontitis by multiplex PCR

The present research decided to study prevalence of Porphyromonas gingivalis and Bacteroides forsythus in chronic periodontitis patient by use of Multiplex PCR. The subgingival plaque samples from 61 patients suffering from chronic periodontitis with probing depth PD > or = 6 and 40 healthy controls were collected by sterile curette. In this study we used two species-specific Forward primers in combination with a single Reverse primer. These primers target variable and conserved region of 16S rRNA gene, respectively. The study included 61 patients (34 women, 27 men; 24-69 years of age; mean 43) and 40 periodontally healthy controls (22 Women, 18 men, 21-69 years in age; mean 41.35%). Porphyromonas gingivalis was detected in 51 samples (83.61%) and 16 samples (40%) of chronic periodontitis patients and healthy subjects, respectively and Bacteroides forsythus was detected in 32 samples (52.50%) of chronic periodontitis patients and was not detected in any sample from healthy persons. We set up Multiplex PCR in order to detect P. gingivalis and B. forsythus simultaneously. The present data suggest that P. gingivalis is a more important cofactor in etiology of chronic periodontitis. Further studies are needed to determine spectrum of pathogenicity of the disease and effective management of diagnosis and treatment in order to decrease the risk of periodontic complicates such as systemic infection.

Prevalence of Epstein-Barr virus type 1 in patients with chronic periodontitis by nested-PCR

The present study evaluated the subgingival presence of Epstein-Barr virus type 1 (EBV-1) in patients with chronic periodontitis with nested-PCR. Subgingival plaque samples from 61 patients with chronic periodontitis with Probing Depth (PD) > or = 6 and 40 healthy controls were collected by sterile curette. DNA was extracted. A nested Polymerase Chain Reaction (PCR) method determined presence of EBV-1. The study included 61 patients (34 women, 27 men; 24-69 years of age; mean 43) and 40 periodontally health controls (22 Women, 18 men, 21-69 years in age; mean 41.35%). EBV type 1 was detected in 37 samples (60.7%) and 1 samples (2.5%) of chronic periodontitis patients and healthy subjects, respectively. This study demonstrated that EBV-1 infection is associated with the activity of chronic periodontitis.

Successful Transthoracic Drainage of a Large Pneumatocele in a Premature Infant

Pulmonary pneumatocele is an unusual complication of bacteria Pneumonia in the neonatal period. They usually develop during the recovery phase, and generally resolve spontaneously within seeks to months [1], We present a premature newborn that developed a large pneumatocele secondary to staphylococcus aureus pneumonia that was treated successfully with a test tube inserted into the pneumatocele. This resulted in complete resolution of the pneumatocele in four days.