Impact of Proton Pump Inhibitor Use on the Effectiveness of Immune Checkpoint Inhibitors in Advanced Cancer Patients

Analysis of immune checkpoint inhibitors for advanced non-small cell lung cancer in patients receiving antacids

BACKGROUND

Proton pump inhibitors (PPIs) are reported to decrease the efficacy of immune checkpoint inhibitors (ICIs), but there are few reports on the association between ICI efficacy and antacids other than PPIs, and simultaneous examination of the effects of antacids, corticosteroids, and non-steroidal anti-inflammatory drugs (NSAIDs) on ICI therapy.

METHODS

We conducted a retrospective study of 381 patients with non-small cell lung cancer who received ICI therapy from January 1, 2016 to December 31, 2022. The primary endpoint was overall survival (OS) and the secondary endpoint was progression-free survival (PFS). Antacids included histamine type 2 receptor antagonists (H2RAs), PPIs, and potassium-competitive acid blockers (P-CABs).

RESULTS

Antacids were administered to 218 patients, including 168 with PPIs, 37 with P-CABs, and 13 with H2RAs. Patients with antacids had worse median PFS and OS than those without antacids (PFS, 2.9 vs. 6.2 months; OS, 12.3 vs. 24.0 months), and those with PPIs, P-CABs, or H2RAs had similar results. However, there were no significant differences between patients with and without antacids when stratified by corticosteroid and NSAID use. Multivariate analyses showed that corticosteroids and NSAIDs administered for cancer-associated symptoms were related to poor prognosis, but antacids including PPIs, P-CABs, or H2RAs were not related.

CONCLUSIONS

Antacids were not related to ICI efficacy when NSAIDs or corticosteroids were taken into consideration. This may be because the most frequent reason for administering NSAIDs and corticosteroids was cancer-associated symptoms, which are a poor prognostic factor, and most of the patients treated with these medications also received antacids.

Clinical evidence for the prognostic impact of metformin in cancer patients treated with immune checkpoint inhibitors

BACKGROUND

Preclinical studies suggest that metformin might enhance the efficacy of immune checkpoint inhibitors (ICIs) and potentially influence the prognoses of cancer patients undergoing ICIs treatment. This study endeavors to assess the prognostic significance of metformin in cancer patients undergoing ICIs therapy, aiming to furnish evidence-based insights for clinical practice.

METHODS

A thorough literature search was conducted across electronic databases to encompass all potential records published before November 20th, 2023. A meta-analysis was executed utilizing Stata 17.0 to derive pooled hazard ratios (HRs) with 95% confidence intervals (CIs) for both overall survival (OS) and progression-free survival (PFS).

RESULTS

A total of 22 studies encompassing 9,011 patients met the inclusion criteria. Meta-analyses revealed a significant correlation between metformin use and poorer OS (HR, 1.13; 95 %CI, 1.04-1.23; P = 0.004) rather than PFS (HR, 1.04; 95 %CI, 0.96-1.14; P = 0.345) among cancer patients undergoing ICIs treatment. Subgroup analysis delineated that the concurrent administration of metformin and ICIs significantly associated with adverse prognoses in the European population (OS: HR, 1.23; 95 %CI, 1.10-1.39; P = 0.001; PFS: HR, 1.14; 95 %CI, 1.02-1.28; P = 0.024).

CONCLUSION

Based on current clinical evidence, concomitant metformin use does not appear to improve the prognostic outcomes for cancer patients undergoing ICIs therapy and may potentially correlate with inferior prognoses. Further studies are imperative to comprehensively elucidate the impact of metformin within the realm of ICIs therapy.

Review article: Contemporary management of gastrointestinal, pancreatic and hepatic toxicities of immune checkpoint inhibitors

BACKGROUND

Immune checkpoint inhibitors (ICIs) are effective oncologic agents which frequently cause immune-related adverse events (irAEs) which can impact multiple organ systems. Onco-Gastroenterology is a novel and emerging subspecialty within gastroenterology focused on cancer treatment-related complications. Gastroenterologists must be prepared to identify and manage diverse immune-mediated toxicities including enterocolitis, hepatitis, pancreatitis and other ICI-induced toxicities.

AIM

To provide a narrative review of the epidemiology, diagnostic evaluation and management of checkpoint inhibitor-induced gastrointestinal and hepatic toxicities.

METHODS

We searched Cochrane and PubMed databases for articles published through August 2023.

RESULTS

Gastrointestinal and hepatic irAEs include most commonly enterocolitis and hepatitis, but also pancreatitis, oesophagitis, gastritis, motility disorders (gastroparesis) and other rarer toxicities. Guidelines from the National Comprehensive Cancer Network, American Society of Clinical Oncology and European Society for Medical Oncology, in combination with emerging cohort and clinical trial data, offer strategies for management of ICI toxicities. Evaluation of irAEs severity by formal classification and clinical stability, and a thorough workup for alternative etiologies which may clinically mimic irAEs underlie initial management. Treatments include corticosteroids, biologics and other immunosuppressive agents plus supportive care; decisions on dosing, timing and choice of steroid adjuncts and potential for subsequent checkpoint inhibitor dosing are nuanced and toxicity-specific.

CONCLUSIONS

Expanding clinical trial and cohort data have clarified the epidemiology and clinical characteristics of gastrointestinal, pancreatic and hepatic toxicities of ICIs. Guidelines, though valuable, remain based principally on retrospective cohort data. Quality prospective, controlled studies may refine algorithms for treatment and potential immunotherapy rechallenge.

Predictive Factors in Metastatic Melanoma Treated with Immune Checkpoint Inhibitors: From Clinical Practice to Future Perspective

The introduction of immunotherapy revolutionized the treatment landscape in metastatic melanoma. Despite the impressive results associated with immune checkpoint inhibitors (ICIs), only a portion of patients obtain a response to this treatment. In this scenario, the research of predictive factors is fundamental to identify patients who may have a response and to exclude patients with a low possibility to respond. These factors can be host-associated, immune system activation-related, and tumor-related. Patient-related factors can vary from data obtained by medical history (performance status, age, sex, body mass index, concomitant medications, and comorbidities) to analysis of the gut microbiome from fecal samples. Tumor-related factors can reflect tumor burden (metastatic sites, lactate dehydrogenase, C-reactive protein, and circulating tumor DNA) or can derive from the analysis of tumor samples (driver mutations, tumor-infiltrating lymphocytes, and myeloid cells). Biomarkers evaluating the immune system activation, such as IFN-gamma gene expression profile and analysis of circulating immune cell subsets, have emerged in recent years as significantly correlated with response to ICIs. In this manuscript, we critically reviewed the most updated literature data on the landscape of predictive factors in metastatic melanoma treated with ICIs. We focus on the principal limits and potentiality of different methods, shedding light on the more promising biomarkers.

Effect of Concomitant Use of Proton Pump Inhibitors on Immunotherapy Clinical Response in Advanced Cancer Patients: Real-Life Setting

The alteration of the gut microbiota mediated by proton pump inhibitor (PPI) drugs could be involved in the clinical response associated with immunotherapy [immunocheckpoint inhibitors (ICIs)] in cancer patients. Due to the current controversy in the scientific evidence, it has been proposed to evaluate the correlation between the concomitant use of PPIs and the effectiveness of immunotherapy in a real clinical practice setting. Single-center retrospective cohort study that included patients treated with anti-PD-1 or anti-CTLA4, including nivolumab, pembrolizumab, atezolizumab, or the combination ipilimumab-nivolumab in metastatic neoplastic disease. The clinical effectiveness of ICI, measured in progression-free survival (PFS) and overall survival (OS), was compared between the PPI-use versus PPI-no-use group. PPI-use group was associated with lower PFS [hazard ratio (HR):1.89 (1.38-2.59), P<0.001] and OS [HR: 2.02 (1.45-2.82), P<0.001] versus PPI-no-use group. However, this difference was not observed for pembrolizumab PFS [HR: 1.38 (0.93-2.39), P=0.160] and OS [HR: 1.41 (0.81-2.44), P=0.187]. The study showed significantly lower PFS and OS in the chronic PPI-use group (P<0.001), recent PPI-use group (P<0.001) and concomitant PPI-use group (P=0.001, 0.007) versus PPI-no-use group. However, late PPI use >30 days after the onset of ICI has no significant effect on the efficacy of treatment [HR: 0.92 (0.49-1.70), P=0.791; HR: 1.10 (0.59-2.05), P=0.756]. The concomitant use of PPIs in immunotherapy is associated with worse clinical outcomes compared with the group without PPI use. In addition, the study shows how the late use of PPIs does not have a significant effect on clinical benefit.

Abnormalities on baseline chest imaging are risk factors for immune checkpoint inhibitor associated pneumonitis

BACKGROUND

Chronic lung disease is a proposed risk factor for immune checkpoint inhibitor pneumonitis (ICI-pneumonitis); however, data is sparse regarding the impact of pre-existing lung disease and baseline chest imaging abnormalities on the risk of developing ICI-pneumonitis.

METHODS

We conducted a retrospective cohort study of patients with ICI treatment for cancer from 2015 to 2019. ICI-pneumonitis was determined by the treating physician with corroboration via an independent physician review and exclusion of alternative etiologies. Controls were patients treated with ICI without a diagnosis of ICI-pneumonitis. Fisher's exact tests, Student's t-tests, and logistic regression were used for statistical analysis.

RESULTS

We analyzed 45 cases of ICI-pneumonitis and 135 controls. Patients with abnormal baseline chest CT imaging (emphysema; bronchiectasis; reticular, ground glass and/or consolidative opacities) had increased risk for ICI-pneumonitis (OR 3.41, 95%CI: 1.68-6.87, p = 0.001). Patients with gastroesophageal reflux disease (GERD) (OR 3.83, 95%CI: 1.90-7.70, p = < 0.0001) also had increased risk for ICI-pneumonitis. On multivariable logistic regression, patients with abnormal baseline chest imaging and/or GERD remained at increased risk for ICI-pneumonitis. Eighteen percent of all patients (32/180) had abnormal baseline chest CT consistent with chronic lung disease without a documented diagnosis.

CONCLUSION

Patients with baseline chest CT abnormalities and GERD were at increased risk for developing ICI-pneumonitis. The large proportion of patients with baseline radiographic abnormalities without a clinical diagnosis of chronic lung disease highlights the importance of multidisciplinary evaluation prior to ICI initiation.

Acid suppressants reduce the therapeutic effect of immune checkpoint inhibitors and increase the risk of acute kidney injury: a meta-analysis

BACKGROUND

Immune checkpoint inhibitors (ICIs) are used in cancer immunotherapy; however, they can lead to immune-related adverse events (irAEs) through immune function of patients. Therefore, this meta-analysis aimed to assess the concomitant effect of acid suppressants (ASs) on ICIs, including several subgroup analyses.

METHODS

We identified related studies and generated the forest plot. The primary endpoint was defined as the change in progression free survival (PFS) and overall survival (OS) with or without ASs administration. We also evaluated the effect of ASs on the incidence of irAEs.

RESULTS

The total hazard ratio (HR) of ASs on PFS with ICI treatment was 1.39 and the 95% confidence interval (95% CI) was 1.21-1.59 (Z: p < 0.00001). Moreover, the total HR of ASs on OS was 1.40 and the 95% CI was 1.21-1.61 (Z: p < 0.00001), suggesting that ASs reduced ICI's therapeutic effect. The total odds ratio (OR) for evaluating the effect of ASs on irAEs was 1.23 with a 95% CI of 0.81-1.88 (Z: p = 0.34). However, ASs significantly worsened acute kidney injury (AKI) (total OR 2.10; 95% CI 1.74-2.53 (Z, p < 0.00001)). Furthermore, although proton pump inhibitors (PPIs) reduced ICI's therapeutic effect, histamine H2-receptor antagonists (H2RAs) did not affect OS.

CONCLUSIONS

It was shown that ASs, especially PPIs, reduced ICI's therapeutic effect, while H2RAs had no effect, and ASs did not affect irAEs; however, it is a risk factor for ICIs-induced AKI.

Machine Learning Approaches for Assessing Risk Factors of Adrenal Insufficiency in Patients Undergoing Immune Checkpoint Inhibitor Therapy

Adrenal insufficiency is a rare, yet life-threatening immune-related adverse event of immune checkpoint inhibitors (ICIs). This study aimed to establish a risk scoring system for adrenal insufficiency in patients receiving anti-programmed cell death 1 (PD-1) or anti-programmed cell death-ligand 1 (PD-L1) agents. Moreover, several machine learning methods were utilized to predict such complications. This study included 209 ICI-treated patients from July 2015 to February 2021, excluding those with prior adrenal insufficiency, previous steroid therapy, or incomplete data to ensure data integrity. Patients were continuously followed up at Gyeongsang National University Hospital, with morning blood samples taken for basal cortisol level measurements, facilitating a comprehensive analysis of their adrenal insufficiency risk. Using a chi-squared test and logistic regression model, we derived the odds ratio and adjusted odds ratio (AOR) through univariate and multivariable analyses. This study utilized machine learning algorithms, such as decision trees, random forests, support vector machines (SVM), and logistic regression to predict adrenal insufficiency in patients treated with ICIs. The performance of each algorithm was evaluated using metrics like accuracy, sensitivity, specificity, precision, and the area under the receiver operating characteristic curve (AUROC), ensuring rigorous assessment and reproducibility. A risk scoring system was developed from the multivariable and machine learning analyses. In a multivariable analysis, proton pump inhibitors (PPIs) (AOR 4.5), and α-blockers (AOR 6.0) were significant risk factors for adrenal insufficiency after adjusting for confounders. Among the machine learning models, logistic regression and elastic net showed good predictions, with AUROC values of 0.75 (0.61-0.90) and 0.76 (0.64-0.89), respectively. Based on multivariable and machine learning analyses, females (1 point), age ≥ 65 (1 point), PPIs (1 point), α-blockers (2 points), and antipsychotics (3 points) were integrated into the risk scoring system. From the logistic regression curve, patients with 0, 1, 2, 4, 5, and 6 points showed approximately 1.1%, 2.8%, 7.3%, 17.6%, 36.8%, 61.3%, and 81.2% risk for adrenal insufficiency, respectively. The application of our scoring system could prove beneficial in patient assessment and clinical decision-making while administering PD-1/PD-L1 inhibitors.

Comedications with Immune Checkpoint Inhibitors: Involvement of the Microbiota, Impact on Efficacy and Practical Implications

Immune checkpoint inhibitors (ICIs) have been a major breakthrough in solid oncology over the past decade. The immune system and the gut microbiota are involved in their complex mechanisms of action. However, drug interactions have been suspected of disrupting the fine equilibrium necessary for optimal ICI efficacy. Thus, clinicians are facing a great deal of sometimes contradictory information on comedications with ICIs and must at times oppose conflicting objectives between oncological response and comorbidities or complications. We compiled in this review published data on the role of the microbiota in ICI efficacy and the impact of comedications. We found mostly concordant results on detrimental action of concurrent corticosteroids, antibiotics, and proton pump inhibitors. The timeframe seems to be an important variable each time to preserve an initial immune priming at ICIs initiation. Other molecules have been associated with improved or impaired ICIs outcomes in pre-clinical models with discordant conclusions in retrospective clinical studies. We gathered the results of the main studies concerning metformin, aspirin, and non-steroidal anti-inflammatory drugs, beta blockers, renin-angiotensin-aldosterone system inhibitors, opioids, and statins. In conclusion, one should always assess the necessity of concomitant treatment according to evidence-based recommendations and discuss the possibility of postponing ICI initiation or switching strategies to preserve the critical window.

The Impact of Concomitant Proton Pump Inhibitors Therapy on Clinical Outcome of Cancer Patients Treated With Immune Checkpoint Inhibitors: A Meta-analysis

BACKGROUND

In patients with advanced cancer receiving immune checkpoint inhibitors (ICIs) therapy, there are conflict perspectives about the influence of concomitant use of proton pump inhibitors (PPIs). We are aimed at exploring the influence of concomitant PPIs exposure on clinical outcome among cancer patients receiving ICIs treatment.

METHODS

We searched relevant literatures in PubMed, EMBASE, and the Cochrane Library without language restrictions. We extracted the data from selected studies and calculated the pooled hazard ratios (HRs) with 95% CIs through professional software for overall survival and progression-free survival among cancer patients undergoing ICIs therapy exposed to PPIs.

RESULTS

Fourteen studies including 6716 advanced cancer patients receiving ICIs treatment were appropriate for analysis judging by pre-set inclusion and exclusion criteria. The result indicated that concomitant PPIs exposure was significantly related to shorter overall survival (HR=1.388; 95% CI: 1.278-1.498, P <0.001) and progression-free survival (HR=1.285; 95% CI: 1.193-1.384, P <0.001) among multiple cancer patients receiving ICIs therapy.

CONCLUSIONS

Our meta-analysis showed that concomitant PPIs exposure had an adverse impact on clinical outcome among patients receiving ICIs therapy. Clinical oncologists must be cautious of PPIs delivery during ICIs treatment.

Drug-drug interactions with proton pump inhibitors in cancer patients: an underrecognized cause of treatment failure

New concepts and drugs have revolutionized medical treatment for cancers. These drugs, which are very expensive and usually well tolerated, have dramatically improved cancer prognosis. We must use them wisely for patients to fully benefit. Gastric acid antisecretory drugs and particularly proton pump inhibitors (PPIs) revolutionized the treatment of gastroduodenal ulcers and severe gastroesophageal reflux, but are frequently overused for symptomatic treatment of epigastric pain or heartburn. Long-term acid suppression may alter the efficacy of many anticancer drugs, such as tyrosine kinase inhibitors (TKIs), cyclin-dependent kinase (CDK) 4/6 inhibitors and immune checkpoint inhibitors (ICIs), by either decreasing gastric acid secretion and thus drug absorption, or by modifying the gut microbiome that modulates the response to ICIs. Oncologists thus need to pay particular attention to the concomitant use of PPIs and anticancer drugs. These interactions translate into major clinical impacts, with demonstrated loss of efficacy for some TKIs (erlotinib, gefitinib, pazopanib), and conflicting results with many other oral drugs, including capecitabine and CDK 4/6 inhibitors. Furthermore, the profound changes in the gut microbiome due to using PPIs have shown that the benefit of using ICIs may be suppressed in patients treated with PPIs. As the use of PPIs is not essential, we must apply the precautionary principle. The first sentence of a recent Comment in Nature was "Every day, millions of people are taking medications that will not help them". We fear that every day millions of cancer patients are taking medications that harm them. While this may well be only association and not causation, there is enough to make us pause until we reach a clear answer. All these data should encourage medical oncologists to refrain from prescribing PPIs, explaining to patients the risks of interaction in order to prevent inappropriate prescription by another physician.

Effect of Antacid Use on Immune Checkpoint Inhibitors in Advanced Solid Cancer Patients: A Systematic Review and Meta-analysis

The influence of antacids use on immune checkpoint inhibitor (ICI) efficacy remains unclear. A systematic review and meta-analysis was performed to evaluate the effect of proton pump inhibitors (PPIs) and histamine-2-receptor antagonists (H2RAs) on ICI efficacy in advanced solid cancer patients. A systematic literature search in PubMed, EMBASE, and Web of Science was performed to retrieve studies investigating the effect of antacid use on ICI efficacy. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and immune-related adverse events were measured using hazard ratios (HRs) or odds ratios (ORs). Thirty studies enrolling 16,147 advanced cancer patients receiving ICI treatment were included. The pooled analysis indicated that PPI use was associated with shorter OS (HR=1.40, 95% CI, 1.25-1.57) and PFS (HR=1.34, 95% CI, 1.19-1.52) in advanced cancer patients treated with ICIs. PPI use did not show effect on ORR or immune-related adverse event of advanced cancer patients receiving ICI treatment. OS, PFS, and ORR did not differ between H2RA users and non-H2RA users. In subgroup analyses, PPI use was associated with shorter OS and PFS in NSCLC and urothelial carcinoma patients and in patients treated with anti-programmed cell death 1 or anti-programmed cell death ligand 1 monotherapy. In addition, ICI efficacy was different in the antacid exposure time frame subgroups. In conclusion, PPI use has a negative effect on OS and PFS among advanced cancer patients receiving ICI treatment. PPIs should be cautiously administered among advanced cancer patients treated with ICI. The safety of H2RAs and the influence of H2RAs on ICI efficacy need further investigation.

A systematic review and meta-analysis evaluating the impact of antibiotic use on the clinical outcomes of cancer patients treated with immune checkpoint inhibitors

Background

Immune checkpoint inhibitors (ICIs) have considerably improved patient outcomes in various cancer types, but their efficacy remains poorly predictable among patients. The intestinal microbiome, whose balance and composition can be significantly altered by antibiotic use, has recently emerged as a factor that may modulate ICI efficacy. The objective of this systematic review and meta-analysis is to investigate the impact of antibiotics on the clinical outcomes of cancer patients treated with ICIs.

Methods

PubMed and major oncology conference proceedings were systematically searched to identify all studies reporting associations between antibiotic use and at least one of the following endpoints: Overall Survival (OS), Progression-Free Survival (PFS), Objective Response Rate (ORR) and Progressive Disease (PD) Rate. Pooled Hazard Ratios (HRs) for OS and PFS, and pooled Odds Ratios (ORs) for ORR and PD were calculated. Subgroup analyses on survival outcomes were also performed to investigate the potential differential effect of antibiotics according to cancer types and antibiotic exposure time windows.

Results

107 articles reporting data for 123 independent cohorts were included, representing a total of 41,663 patients among whom 11,785 (28%) received antibiotics around ICI initiation. The pooled HRs for OS and PFS were respectively of 1.61 [95% Confidence Interval (CI) 1.48-1.76] and 1.45 [95% CI 1.32-1.60], confirming that antibiotic use was significantly associated with shorter survival. This negative association was observed consistently across all cancer types for OS and depending on the cancer type for PFS. The loss of survival was particularly strong when antibiotics were received shortly before or after ICI initiation. The pooled ORs for ORR and PD were respectively of 0.59 [95% CI 0.47-0.76] and 1.86 [95% CI 1.41-2.46], suggesting that antibiotic use was significantly associated with worse treatment-related outcomes.

Conclusion

As it is not ethically feasible to conduct interventional, randomized, controlled trials in which antibiotics would be administered to cancer patients treated with ICIs to demonstrate their deleterious impact versus control, prospective observational studies and interventional trials involving microbiome modifiers are crucially needed to uncover the role of microbiome and improve patient outcomes. Such studies will reduce the existing publication bias by allowing analyses on more homogeneous populations, especially in terms of treatments received, which is not possible at this stage given the current state of the field. In the meantime, antibiotic prescription should be cautiously considered in cancer patients receiving ICIs.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42019145675.

Do proton pump inhibitors alter the response to immune checkpoint inhibitors in cancer patients? A meta-analysis

Introduction

Gut microbiota can significantly affect the effectiveness of immune checkpoint inhibitors (ICIs) in cancer patients. Recently, antibiotics were shown to decrease survival rate of patients treated by ICIs. Proton pump inhibitors (PPIs) can indeed modulate microbiota's diversity, therefore altering ICIs response. A meta-analysis was performed based on published data to verify this hypothesis.

Methods

In this study, over 41 publications, exploring the impact of concomitant PPI treatment on outcomes of ICI-treated patients, were analyzed. Evaluated endpoints were overall survival (OS) and progression-free survival (PFS). Pooled hazard ratios (HRs) with a 95% confidence interval (CI) were reported in ICIs in PPI users versus non-PPI users. Subgroup analyses were performed to minimize the impact of study heterogeneity and to investigate the influence of PPI on the different groups of interest. There was no evidence of publication bias for OS and PFS analysis in subgroup analysis.

Results

Forty-one studies were included in the meta-analysis, including a total of 20,042 patients. OS of patients receiving ICIs was negatively correlated in patients concomitantly treated with PPI (HR=1.37; 95%CI, 1.23-1.52). PFS of cancer patients receiving ICIs was also negatively correlated with PPI treatment (HR=1.28; 95%CI, 1.15-1.42). PPI and ICI use was associated with worst OS and PFS not only for non-small-cell lung cancer (NSCLC) or urothelial cancer patients but also for patients treated with anti PD-1 (OS) and anti PD-L1 (OS and PFS) immunotherapies when administered in non-first line and when PPI was received as baseline treatment or in 60 days before ICI initiation. PPI and ICI use also showed the worst OS and PFS for patients from Europe and Asia.

Conclusion

This meta-analysis suggests that PPI treatment leads to significantly worse outcomes in advanced cancer patients treated by ICIs in terms of PFS and OS.

The Association between Baseline Proton Pump Inhibitors, Immune Checkpoint Inhibitors, and Chemotherapy: A Systematic Review with Network Meta-Analysis

(1) Although emerging evidence suggests that proton pump inhibitor (PPI)-induced dysbiosis negatively alters treatment response to immune checkpoint inhibitors (ICIs) in cancer patients, no study systematically investigates the association between PPIs, ICIs, and chemotherapy; (2) Cochrane Library, Embase, Medline, and PubMed were searched from inception to 20 May 2022, to identify relevant studies involving patients receiving ICIs or chemotherapy and reporting survival outcome between PPI users and non-users. Survival outcomes included overall survival (OS) and progression-free survival (PFS). Network meta-analyses were performed using random-effects models. p-scores, with a value between 0 and 1, were calculated to quantify the treatment ranking, with a higher score suggesting a higher probability of greater effectiveness. We also conducted pairwise meta-analyses of observational studies to complement our network meta-analysis; (3) We identified 62 studies involving 26,484 patients (PPI = 8834; non-PPI = 17,650), including non-small cell lung cancer (NSCLC), urothelial carcinoma (UC), melanoma, renal cell carcinoma (RCC), hepatocellular carcinoma (HCC), and squamous cell carcinoma (SCC) of the neck and head. Eight post-hoc analyses from 18 randomized-controlled trials were included in our network, which demonstrated that, in advanced NSCLC and UC, patients under ICI treatment with concomitant PPI (p-score: 0.2016) are associated with both poorer OS (HR, 1.49; 95% CI, 1.37 to 1.67) and poorer PFS (HR, 1.41; 95% CI, 1.25 to 1.61) than those without PPIs (p-score: 1.000). Patients under ICI treatment with concomitant PPI also had poorer OS (HR, 1.18; 95% CI, 1.07 to 1.31) and poorer PFS (HR, 1.30; 95% CI, 1.14 to 1.48) in comparison with those receiving chemotherapy (p-score: 0.6664), implying that PPIs may compromise ICI's effectiveness, making it less effective than chemotherapy. Our pairwise meta-analyses also supported this association. Conversely, PPI has little effect on patients with advanced melanoma, RCC, HCC, and SCC of the neck and head who were treated with ICIs; (4) "PPI-induced dysbiosis" serves as a significant modifier of treatment response in both advanced NSCLC and UC that are treated with ICIs, compromising the effectiveness of ICIs to be less than that of chemotherapy. Thus, clinicians should avoid unnecessary PPI prescription in these patients. "PPI-induced dysbiosis", on the other hand, does not alter the treatment response to ICIs in advanced melanoma, RCC, HCC, and SCC of the head and neck.

Effects of PPIs use on clinical outcomes of urothelial cancer patients receiving immune checkpoint inhibitor therapy

Objective: Immune checkpoint inhibitors (ICIs) have recently demonstrated promising performance in improving the prognosis of urological cancer patients. The goal of this meta-analysis was to determine the impact of PPI use on the clinical outcomes of urological cancer patients receiving ICI therapy.

Methods: Before 6 May 2022, the eligible literature was searched using PubMed, EMBASE, Cochrane Library, and Google Scholar. The clinical outcomes were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR).

Results: A total of six articles met the inclusion criteria, and of the 1980 patients with advanced or metastatic urothelial cancers (UC) included. The meta-analysis displayed that PPI use could increase the risk of progression by 50.7% (HR: 1.507, 95% CI: 1.327–1.711, p < 0.001) and death by 58.7% (HR: 1.587, 95% CI: 1.367–1.842, p < 0.001), and reduce the ORR (OR: 0.503, 95% CI: 0.360–0.703, p < 0.001) in UC patients receiving ICIs. No significant heterogeneity and publication bias existed. Sensitivity analysis proved that the results were stable and reliable.

Conclusion: The meta-analysis indicated that concomitant PPI use was significantly associated with low clinical benefit in UC patients.

Effect of proton pump inhibitors on the clinical outcomes of PD-1/PD-L1 inhibitor in solid cancer patients

BACKGROUND

Some concomitant drugs may affect the efficacy of programmed death protein-1/ ligand-1 (PD-1/L1) inhibitors. Among the various concomitant drugs, proton-pump inhibitors (PPI) have attracted some attention but have not reached a conclusion. We conducted a meta-analysis to evaluate the impact of PPIs on the survival of cancer patients treated with PD-1/L1 inhibitors.

MATERIAL/METHODS

Related databases and conferences reports were searched. Studies that reported the relationship between PPI use and clinical outcomes of PD-1/L1 inhibitors were included. Meta-analysis was conducted to obtain pooled hazard ratios (HR)s with 95% confidence interval (CI).

RESULTS

Eight studies involving 4869 cancer patients were included. Meta-analysis showed that PPI use was associated with worse overall survival (OS) (HR = 1.43, 95% CI 1.32-1.56), worse progression free survival (PFS) (HR = 1.30, 95% CI 1.20-1.40), and decreased objective response (odds ratio = 0.71, 95% CI 0.58-0.87) in cancer patients receiving PD-1/L1 inhibitors. Neither cancer type nor therapy type affected the effect of concomitant PPIs on the OS and PFS. In the subgroup of studies with a population size <500, PPIs did not reduce the OS, but the PFS. Only 1 single-center study was conducted, showing that PPI use did not affect the OS and PFS. There was no evidence of publication bias among included studies.

CONCLUSION

Concomitant PPI use was correlated with worse clinical outcomes in cancer patients treated by PD-1/L1 inhibitors. Further prospective clinical and experimental studies are needed to confirm the effect and mechanism of PPI in worsening the clinical outcome of PD-1/L1 inhibitors.

Concomitant Use of Statins, Metformin, or Proton Pump Inhibitors in Patients with Advanced Renal Cell Carcinoma Treated with First-Line Combination Therapies

BACKGROUND

Drug-drug interactions are a major concern in oncology and may potentially affect the outcome of patients with cancer.

OBJECTIVE

In this study, we aimed to determine whether the concomitant use of statins, metformin, or proton pump inhibitors affects survival in patients with metastatic renal cell carcinoma treated with first-line combination therapies.

METHODS

Medical records of patients with documented metastatic renal cell carcinoma between January 2016 and November 2021 were reviewed at 17 participating centers. This research was conducted in ten institutions, including both referral centers and local hospitals. Patients were assessed for overall survival, progression-free survival, and overall clinical benefit. Univariate and multivariate analyses were conducted to explore the association of variables of interest with overall survival and progression-free survival.

RESULTS

A total of 304 patients receiving dual immunotherapy (51%) or immunotherapy/vascular endothelial growth factor-tyrosine kinase inhibitor (49%) combinations were eligible for inclusion in this retrospective study. Statin use was a significant prognostic factor for longer overall survival in a univariate analysis (hazard ratio 0.48, 95% confidence interval 0.26-0.87; p = 0.016) and a multivariate analysis (hazard ratio 0.48, 95% confidence interval 0.31-0.74; p < 0.001) and was significantly associated with an overall clinical benefit (83% in statin users vs 71% in non-users; p = 0.045). Otherwise, the use of metformin or proton pump inhibitors did not affect the outcome of these patients.

CONCLUSIONS

Our study suggests a prognostic impact of statin use in patients receiving first-line immuno-oncology combinations. The mechanism of this interaction warrants further elucidation.

Association of proton pump inhibitor use with survival outcomes in cancer patients treated with immune checkpoint inhibitors: a systematic review and meta-analysis

Background:

Proton pump inhibitors (PPIs) have been shown to regulate the gut microbiome and affect the response to immune checkpoint inhibitors (ICIs). Contradictory results on survival have been observed in patients concomitantly treated with ICIs and PPIs. We performed a systematic review and meta-analysis to determine the association between PPI use and survival outcomes in ICI-treated cancer patients.

Methods:

EMBASE, MEDLINE/PubMed, Cochrane Library databases, and major oncology conference proceedings were searched. Studies comparing overall survival (OS) and progression-free survival (PFS) between PPI-treated and PPI-free groups of ICI-treated cancer patients were included. Data regarding study and patient characteristics, ICI and PPI treatments, and survival outcomes were extracted. Hazard ratios (HRs) with 95% confidence interval (CI) were pooled using random effects models. Subgroup meta-analyses and meta-regressions were performed to explore possible factors of heterogeneity among the studies.

Results:

A total of 33 studies were included, comprising 7383 ICI- and PPI-treated patients and 8574 ICI-treated and PPI-free patients. The pooled HR was 1.31 (95% CI, 1.19–1.44; p < 0.001) for OS and 1.30 (95% CI, 1.17–1.46; p < 0.001) for PFS, indicating a significant negative association between PPI use and survival in ICI-treated patients. Subgroup meta-analyses by factors including cancer type, ICI type, and time window of PPI use revealed that ICI and PPI use impacted survival in patients with non-small cell lung or urothelial cancer, patients treated with anti-PD-1/PD-L1 antibodies, and patients receiving PPI as baseline treatment or 60 days before ICI treatment initiation.

Conclusions:

PPI use in patients treated with ICIs was associated with shorter OS and PFS, especially in several specific subgroups of cancer patients. PPIs should be strictly controlled and appear to not impact survival if given temporarily after ICI initiation. These observations could provide the basis for clinical guidelines for concomitant PPI and ICI use.

The Correlation between the Use of the Proton Pump Inhibitor and the Clinical Efficacy of Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer

Background. To determine if the use of the Proton Pump Inhibitors (PPI) impacts the clinical efficacy of Immune Checkpoint Inhibitors (ICIs) in Non-Small Cell Lung Cancer (NSCLC), a meta-analysis was conducted. Method. Eleven studies from PubMed, EMBASE, Cochrane Library, Web of Science, and other databases up to May 2022, were selected. The pertinent clinical outcomes were assessed by applying the Progression-free survival (PFS), Overall Survival (OS), Hazard Ratio (HR), and 95% Confidence Interval (CI). Result. This study included eleven articles containing 7,893 NSCLC patients. The result indicated that PPI use was dramatically related to poor OS (HR: 1.30 [1.10–1.54]), and poor PFS (HR: 1.25 [1.09–1.42]) in case of patients treated with ICIs. With regard to the subgroup analysis, PPI use was dramatically associated with poor OS (Europe: HR = 1.48 [1.26, 1.74], Worldwide: HR = 1.54 [1.24, 1.91]), and poor PFS (Europe: HR = 1.36 [1.18, 1.57], Worldwide: HR = 1.34 [1.16, 1.55]) in patients from Europe and multi-center studies across the world, poor OS in patients with age less than or equal to 65 (HR = 1.56 [1.14, 2.15]), poor PFS in patients aged more than 65 (HR = 1.36 [1.18, 1.57]), poor OS for patients receiving with PD-1 (HR = 1.37 [1.04, 1.79]), poor PFS for patients receiving with PD-L1 (HR = 1.33 [1.19, 1.49]), and poor OS (−30: HR = 1.89 [1.29, 2.78], ±30: HR = 1.44 [1.27, 1.64]) and poor PFS (−30: HR = 1.51 [1.11, 2.05], ±30: HR = 1.32 [1.20, 1.45]) for patients who received PPI at 30 days before and/or after starting the ICIs treatment. Conclusion. Our meta-analysis indicated that PPI combined with ICIs in the treatment of NSCLC patients could result in poor OS and PFS. PPI use should be extremely cautious in clinical practices to avoid the impact on the efficacy of the ICIs.

Impact of proton-pump inhibitors on the efficacy of immune checkpoint inhibitors in non-small cell lung cancer: A systematic review and meta-analysis

Introduction

Immune checkpoint inhibitors (ICI) is a rapidly evolving treatment modality for stage IV non-small cell lung cancer (NSCLC). Concomitant proton pump inhibitor (PPI) use can potentially reduce the clinical efficacy of ICIs; however, the consensus in recent literature has been conflicting. This study aims to analyze overall survival (OS) and progression-free survival (PFS) outcomes in patients with NSCLC on ICI and concomitant PPI therapy.

Methods

A literature search was done in 3 databases (Pubmed/Medline, Embase, and Cochrane Central). All studies meeting the inclusion criteria assessing the impact of PPIs on the efficacy of ICI in NSCLC patients were systematically identified. A random-effects network meta-analysis evaluated OS and PFS in the two arms.

Results

Four studies with 2,940 patients are included in our analysis. ICI usage alone was associated with significantly better OS [HR = 1.46, 95% CI = 1.27–1.67, P < 0.00001] and PFS [HR = 1.31, 95% CI = 1.17–1.47, P < 0.00001] when compared to concomitant PPI and ICI therapy.

Conclusion

The concomitant use of PPIs during ICI therapy significantly worsens clinical outcomes with shorter OS and increased risk of disease progression in patients with NSCLC.

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Immune checkpoint inhibitors are a rapidly evolving treatment regime used for various cancer therapies. The role of other medications in their effectiveness remains conflicted. Proton Pump Inhibitors are one of the most commonly prescribed medications and are particularly often prescribed to cancer patients.

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Our study finds that Proton Pump Inhibitors worsen the outcomes of overall survival and increase risk of disease progression in Non-Small Cell Lung Carcinoma.

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We hope that this study will enlighten providers to use proton pump inhibitors more judiciously in patients with Non-Small Cell Lung Carcinoma.

An Up-To-Date Investigation Into the Correlation Between Proton Pump Inhibitor Use and the Clinical Efficacy of Immune Checkpoint Inhibitors in Advanced Solid Cancers: A Systematic Review and Meta-Analysis

Background

Although immune checkpoint inhibitors (ICIs) have revolutionized the current anticancer therapies, a considerable proportion of patients are found to hardly benefit from these drugs. Accumulating studies have demonstrated that concomitant proton pump inhibitor (PPI) use may affect the clinical efficacy of ICIs; however, their results are inconsistent. In this study, based on updated evidence, we aimed to perform a meta-analysis to clarify the prognostic significance of PPI use in advanced solid cancer patients receiving ICI therapy.

Methods

Eligible literature was searched using PubMed, Cochrane Library, Web of Science, EMBASE, and other network resources before July 2021. Clinical outcome was evaluated using overall survival (OS) and progression-free survival (PFS). The correlation of PPI use with OS or PFS was determined based on hazard ratios (HRs) and 95% confidence intervals (CIs).

Results

A total of 17 studies enrolling 9,978 ICI-treated cancer patients were included in our meta-analysis. The global analysis demonstrated that PPI use was significantly correlated with worse OS [HR = 1.29 (1.10-1.50)] instead of PFS [HR = 1.19 (0.98-1.44)] in solid cancer patients receiving ICI therapy. In a subgroup analysis, the negative correlation of PPI use with ICI efficacy was significant in patients with non-small cell lung cancer [PFS, HR = 1.27 (1.10-1.47)] and urothelial carcinoma [OS, HR = 1.55 (1.31-1.84), PFS, HR = 1.52 (1.13-2.06)] and mixed cohorts containing multiple cancer types [OS, HR = 1.40 (1.16-1.69)], while an opposite result was observed in the PFS of patients with melanoma [HR = 0.48 (0.25-0.90)]. Moreover, the unfavorable prognostic impact of PPI use was also significant in patients over 65 years old [OS, HR = 1.28 (1.05-1.55), PFS, HR = 1.32 (1.12-1.56)] or those receiving anti-PD-1 [OS, HR = 1.37 (1.04-1.79)] or anti-PD-L1 therapies (OS, HR = 1.49 (1.30-1.69), PFS, HR = 1.34 (1.20-1.50). Finally, PPI use was significantly correlated with a worse prognosis in patients receiving PPIs 30 days before and/or after ICI initiation (OS, HR = 1.38 (1.18-1.62), PFS, HR = 1.23 (1.06-1.43)).

Conclusion

Although our global analysis revealed PPI use was not correlated with the PFS of ICI-treated patients, considering the results of our subgroup analysis, PPIs should be still cautiously used shortly before or during ICI therapy. Furthermore, more clinical validations and related mechanism investigations are of great necessity to clarify the clinical correlation of PPI use with ICI efficacy.

Systematic Review Registration

[https://www.crd.york.ac.uk/prospero/], PROSPERO [No. CRD42021243707].

Impact of Proton Pump Inhibitors and Histamine-2-Receptor Antagonists on Non-Small Cell Lung Cancer Immunotherapy: A Systematic Review and Meta-Analysis

Simple Summary

The current meta-analysis highlighted that proton pump inhibitors (PPIs) and histamine-2-receptor antagonists (H2RAs) could impact immune checkpoint inhibitors (ICIs) efficacy in NSCLC patients, highlighting the need for a deeper comprehension of factors involved in treatment response or resistance. Since the number of indications and NSCLC patients receiving ICIs is supposed to increase further soon, identifying the impact of these agents on NSCLC immunotherapy represents a compelling and urgent need regarding NSCLC.

Abstract

(1) Background: In recent years, immunotherapy has revolutionized the treatment landscape of non-small cell lung cancer (NSCLC), representing a therapeutic breakthrough in this field. Antacid agents such as proton pump inhibitors (PPIs) and histamine-2-receptor antagonists (H2RAs) are commonly prescribed for extended periods in NSCLC patients, and these drugs have the potential to modify the efficacy of immune checkpoint inhibitors (ICIs). (2) Materials and Methods: Herein, we conducted a systematic review and meta-analysis to investigate the impact of PPIs and H2RAs on progression-free survival (PFS) and overall survival (OS) among patients receiving immunotherapy for metastatic NSCLC. Effect measures for OS were Hazard Ratios (HRs) and 95% Confidence Intervals (CIs), which were extracted from available studies. Forest plots were used to assess HRs to describe the relationship between treatment and OS in the specified cohorts of patients. (3) Results: Six studies were included in the analysis, involving 2267 patients. The pooled HRs for OS and PFS were 1.4 (95% CI, 1.25–1.58) and 1.29 (95% CI, 1.17–1.43), respectively, suggesting that PPIs and H2RAs administration was negatively associated with PFS and OS. (4) Conclusion: Concomitant antacid use could modify the activity of ICIs in NSCLC patients.

Long-Term Use of Proton Pump Inhibitors in Cancer Patients: An Opinion Paper

Simple Summary

Proton pump inhibitors are frequently used in cancer patients to alleviate some symptoms, epigastric pain or heartburn. However, acid suppression decreases the absorption of some oral-targeted anticancer treatments (tyrosine kinase inhibitors, CDK4/6 inhibitors) and induces changes in the gut microbiome. Recent data are showing that these interactions have important clinical impacts and medical oncologists and patients must be aware of these possible interactions.

Abstract

Multikinase inhibitors (MKIs), and particularly tyrosine kinase inhibitors (TKIs) and immune checkpoint inhibitors (CPIs), are currently some of the major breakthroughs in cancer treatment. Proton pump inhibitors (PPIs) revolutionised the treatment of acid-related diseases, but are frequently overused for epigastric pain or heartburn. However, long-term acid suppression from using PPIs may lead to safety concerns, and could have a greater impact in cancer patients undergoing therapy, like bone fractures, renal toxicities, enteric infections, and micronutrient deficiencies (iron and magnesium). Moreover, acid suppression may also affect the pharmacokinetics of drugs (at least during acid suppression) and decrease the absorption of many molecularly-targeted anticancer therapies, which are mostly weak bases with pH-dependent absorption. This type of drug-drug interaction may have detrimental effects on efficacy, with major clinical impacts described for some orally administrated targeted therapies (erlotinib, gefitinib, pazopanib, palbociclib), and conflicting results with many others, including capecitabine. Furthermore, the long-term use of PPIs results in severe alterations to the gut microbiome and recent retrospective analyses have shown that the benefit of using CPIs was suppressed in patients treated with PPIs. These very expensive drugs are of great importance because of their efficacy. As the use of PPIs is not essential, we must apply the precautionary principle. All these data should encourage medical oncologists to refrain from prescribing PPIs, explaining to patients the risks of interaction in order to prevent inappropriate prescription by another physician.