Atezolizumab (MPDL3280A) Monotherapy for Patients With Metastatic Urothelial Cancer: Long-term Outcomes From a Phase 1 Study

Rogaratinib Plus Atezolizumab in Cisplatin-Ineligible Patients With FGFR RNA-Overexpressing Urothelial Cancer: The FORT-2 Phase 1b Nonrandomized Clinical Trial

Importance

The oral pan-fibroblast growth factor receptor inhibitor rogaratinib previously demonstrated encouraging safety and efficacy in a phase 1 study of patients with urothelial cancer (UC) overexpressing FGFR messenger RNA (mRNA).

Objective

To evaluate the safety, pharmacokinetics, and preliminary efficacy of rogaratinib in combination with the programmed cell death 1 ligand 1 (PD-L1) inhibitor atezolizumab in cisplatin-ineligible patients with FGFR mRNA-positive, locally advanced/metastatic UC.

Design, Setting, and Participants

The FORT-2 nonrandomized clinical trial was an open-label, single-arm, multicenter study conducted between May 15, 2018, and July 16, 2021, in 30 centers across Asia, Europe, and North America. Eligible patients had locally advanced/metastatic UC with FGFR1/3 mRNA overexpression and were ineligible for cisplatin-based chemotherapy. The data analysis was completed from July 2022 to September 2022.

Interventions

Patients received rogaratinib 600 mg or rogaratinib 800 mg twice daily in combination with intravenous atezolizumab 1200 mg every 21 days.

Main Outcomes and Measures

Primary end points included safety, tolerability, and the recommended phase 2 dose (RP2D) of rogaratinib in combination with atezolizumab.

Results

Among 153 patients screened, 73 (48%) had tumors with FGFR1/3 mRNA overexpression, and 37 patients were enrolled and treated (median [range] age, 75.0 [47.0-85.0] years; 32 [87%] male). The most common treatment-emergent adverse events (TEAEs) included diarrhea in 23 patients (62%), hyperphosphatemia in 19 (51%), and fatigue in 15 (41%). Grade 3 or higher TEAEs were reported in 27 patients (73%), and 4 grade 5 TEAEs were reported, though unrelated to treatment. The RP2D was rogaratinib 600 mg in combination with atezolizumab 1200 mg. At the RP2D, the overall response rate was 53.8% in the rogaratinib 600 mg group, including 4 patients (15%) with complete responses; 12 responders (86%) did not have an FGFR3 gene alteration, and 11 (79%) had low PD-L1 expression.

Conclusions and Relevance

In this phase 1b nonrandomized clinical trial, rogaratinib plus atezolizumab demonstrated a manageable safety profile, with no unexpected safety signals. Efficacy for this combination at the RP2D was observed in tumors with low PD-L1 and was not dependent on FGFR3 gene alterations, suggesting broad potential benefit for patients with locally advanced/metastatic UC and FGFR mRNA overexpression.

Trial Registration

ClinicalTrials.gov Identifier: NCT03473756.

Alternative splicing regulation and its therapeutic potential in bladder cancer

Bladder cancer is one of the leading causes of mortality globally. The development of bladder cancer is closely associated with alternative splicing, which regulates human gene expression and enhances the diversity of functional proteins. Alternative splicing is a distinctive feature of bladder cancer, and as such, it may hold promise as a therapeutic target. This review aims to comprehensively discuss the current knowledge of alternative splicing in the context of bladder cancer. We review the process of alternative splicing and its regulation in bladder cancer. Moreover, we emphasize the significance of abnormal alternative splicing and splicing factor irregularities during bladder cancer progression. Finally, we explore the impact of alternative splicing on bladder cancer drug resistance and the potential of alternative splicing as a therapeutic target.

Efficacy of Antibody Drug Conjugates Alone and in Combination with other Agents in Metastatic Urothelial Carcinoma: A Scoping Review

INTRODUCTION

Antibody drug conjugates represent a promising class of antineoplastic agents comprised of a monoclonal antibody linked to a potent cytotoxic payload for targeted delivery of chemotherapy to tumors. Various antibody drug conjugates have demonstrated impressive efficacy in patients with metastatic urothelial carcinoma in clinical trials, leading to two FDA approved therapies and several other agents and combinations in clinical development.

MATERIALS AND METHODS

A comprehensive systematic review was undertaken utilizing the principles of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Queried databases included Ovid MEDLINE, Ovid Embase, Web of Science Core Collection and Cochrane CENTRAL Trials. The search sought to identify prospective therapeutic clinical trials in humans with metastatic urothelial carcinoma with a single-arm or randomized controlled trial design investigating antibody drug conjugate-containing regimens.

RESULTS

The literature search yielded 4,929 non-duplicated articles, of which 30 manuscripts and conference abstracts were included, which derived from 15 clinical trials including 19 separate cohorts with efficacy outcome results. Eleven trials investigated ADC monotherapy, while two investigated combination regimens, and the remaining two studies were mixed. Five unique ADC targets were represented including Nectin-4, Trop-2, HER2, Tissue Factor, and SLITRK6. Twelve clinical trial cohorts required prior treatment (63%). Objective response rate was reported for all studies and ranged from 27-52% for ADC monotherapies and 34-75% for ADC plus anti-PD-1 agents. Time to event outcome reporting was highly variable.

CONCLUSION

In addition to enfortumab vedotin and sacituzumab govitecan, various HER2-targeted antibody drug conjugates and ADC-anti-PD-1 combination regimens have demonstrated efficacy in clinical trials and are poised for clinical advancement.

Pan-cancer analysis of PLAU indicates its potential prognostic value and correlation with neutrophil infiltration in BLCA

BACKGROUND

PLAU is known as a selected serine protease converting plasminogen to plasmin. The role of PLAU in the development of pan-cancer, especially bladder urothelial carcinoma (BLCA) remains unclear.

METHOD

A variety of online tools and cancer databases, including TCGA, GETx, HPA database, GSCALite, UALCAN, ESTIMATE, CIBERSORT, ssGSEA algorithms and SangerBox website, were applied to investigate the associations between PLAU expression and prognosis, genetic alterations, pathway activation, and tumor immunity in pan-cancer. Through cBioPortal and STITCH platforms, the oncogenic role of PLAU and related targeting medicines in BLCA were also explored. We verified the expression of PLAU in pan-cancer cells and its function in bladder cancer cell lines using wet-lab experiments.

RESULTS

PLAU expression levels were significantly higher in most cancer tissues. PLAU had a certain accuracy in the diagnosis of various types of cancers (90 % AUC > 0.700). In BLCA, PLAU has abundant methylated sites and showed statistical differences in clinical features. PLAU was involved in tumor immune infiltration, and especially positively correlated with neutrophil infiltration. High-expressed PLAU indicated poorer prognosis in the BLCA patients receiving Atezolizumab. A high mRNA and protein expression levels of PLAU were observed in pan-cancer cell lines, especially BLCA cells. Knockdown of PLAU inhibited the invasive, proliferative, and aggressive phenotypes of bladder cancer cells. Immunohistochemical staining validated PLAU's higher expression in BLCA tissues than in adjacent non-cancerous tissues. And overexpression of PLAU was associated with more advanced TNM stage, and high infiltrating depth.

CONCLUSION

Our study revealed that PLAU can serve as a potential therapeutic target and prognostic marker for various malignancies, especially BLCA.

Incidence of Cutaneous Immune-Related Adverse Events and Outcomes in Immune Checkpoint Inhibitor-Containing Regimens: A Systematic Review and Meta-Analysis

Immune checkpoint inhibitors (ICIs) are used to treat many cancers, and cutaneous immune-related adverse events (cirAEs) are among the most frequently encountered toxic effects. Understanding the incidence and prognostic associations of cirAEs is of importance as their uses in different settings, combinations, and tumor types expand. To evaluate the incidence of cirAEs and their association with outcome measures across a variety of ICI regimens and cancers, we performed a systematic review and meta-analysis of published trials of anti-programmed death-1/ligand-1 (PD-1/PD-L1) and anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) ICIs, both alone and in combination with chemotherapy, antiangiogenic agents, or other ICIs in patients with melanoma, renal cell carcinoma, non-small cell lung cancer, and urothelial carcinoma. Key findings of our study include variable cirAE incidence among tumors and ICI regimens, positive association with increased cirAE incidence and response rate, as well as significant association between increased vitiligo incidence and overall survival. Across 174 studies, rash, pruritis, and vitiligo were the most reported cirAEs, with incidences of 16.7%, 18.0%, and 6.6%, respectively. Higher incidence of cirAEs was associated with ICI combination regimens and with CTLA-4-containing regimens, particularly with higher doses of ipilimumab, as compared to PD-1/L1 monotherapies. Outcome measures including response rate and progression-free survival were positively correlated with incidence of cirAEs. The response rate and incidence of pruritis, vitiligo, and rash were associated with expected rises in incidence of 0.17% (p = 0.0238), 0.40% (p = 0.0010), and 0.18% (p = 0.0413), respectively. Overall survival was positively correlated with the incidence of pruritis, vitiligo, and rash; this association was significant for vitiligo (p = 0.0483). Our analysis provides benchmark incidence rates for cirAEs and links cirAEs with favorable treatment outcomes at a study level across diverse solid tumors and multiple ICI regimens.

The poor antitumor effect of pembrolizumab in advanced upper urothelial carcinoma with renal parenchymal invasion

OBJECTIVES

We investigated poor prognosticators in advanced or unresectable urothelial carcinoma, focusing on renal parenchymal invasion (RPI).

METHODS

This study included 48 bladder cancer (BC) and 67 upper tract urothelial carcinoma (UTUC) patients treated with pembrolizumab from December 2017 to September 2022 at Kobe University Hospital. Medical records were retrospectively reviewed for clinical characteristics, objective response rate (ORR), progression-free survival (PFS), and overall survival (OS). Multivariate analyses were performed using the Cox proportional hazard regression model to identify parameters associated with either PFS or OS.

RESULTS

Of 67 UTUC patients, 23 had RPI and 41 patients did not, while 3 cases could not be evaluated. Patients with RPI were predominantly elderly and had liver metastases. ORR for patients with RPI was 8.7%, while it was 19.5% for those without RPI. PFS was significantly shorter for patients with RPI compared with those without RPI. Patients with RPI had significantly shorter OS than those without RPI. On multivariate analysis, performance status (PS) ≥ 2, neutrophil-lymphocyte ratio (NLR) ≥ 3, C-reactive protein ≥0.3 mg/dL and RPI were independent prognostic factors for PFS. PS ≥ 2, NLR ≥ 3, visceral metastasis and RPI were independent prognostic factors for OS. UTUC patient OS was significantly shorter than BC patient OS, while no significant difference in PFS or OS was observed between BC patients and UTUC patients without RPI.

CONCLUSIONS

RPI was a poor prognostic factor in advanced urothelial carcinoma treated with pembrolizumab, possibly resulting in a poorer prognosis for UTUC compared with BC.

New developments in the mechanism and application of immune checkpoint inhibitors in cancer therapy (Review)

The use of immune checkpoint inhibitors (ICIs) has been demonstrated in the treatment of numerous types of cancer and ICIs have remained a key focus of cancer research. However, improvements in survival rates only occur in a subset of patients, due to the complexity of drug resistance. Therefore, further investigations are required to identify predictive biomarkers that distinguish responders and non‑responders. Combined therapeutics involving ICIs and other modalities demonstrate potential in overcoming resistance to ICIs; however, further preclinical and clinical trials are required. Concurrently, prompt recognition and intervention of immune‑related adverse events are crucial to optimize the use of ICIs in clinical treatment. The present study aimed to review the current literature surrounding the mechanisms and application of ICIs, with the aim of providing a theoretical basis for clinicians.

Immunotherapy with or without targeted therapy for metastatic upper tract urothelial carcinoma: case report and literature review

Background

Immune checkpoint inhibitors (ICIs) have been proved having a better safety profile compared to platinum-based chemotherapy and have demonstrated encouraging anti-tumor therapeutic effects for patients with metastatic urothelial carcinoma (mUC). However, few studies have evaluated the efficacy of ICIs in patients with metastatic upper tract urothelial carcinoma (mUTUC).

Case reports

Case 1 was a 71-year-old male patient diagnosed with left renal pelvic carcinoma, accompanied by a metastasis to the second lumbar spine. As the patient became refractory to chemotherapy, four cycles of camrelizumab, one of the ICIs, were administered, which helped to control the metastases and extend the patient's progression-free survival to five months. Case 2 was an 88-year-old female with middle and lower right ureter carcinoma with right iliac arteriovenous invasion. The patient received five cycles of camrelizumab plus vascular endothelial growth factor receptor 2 (VEGFR2) inhibitors and achieved stable disease.

Conclusion

For patients who are ineligible for chemotherapy, immunotherapy might be a feasible treatment, regardless of whether or not they are given VEGFR2 inhibitors.

Microsomal Prostaglandin E Synthase-1 and -2: Emerging Targets in Non-Alcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) affects a substantial proportion of the general population and is even more prevalent in obese and diabetic patients. NAFLD, and particularly the more advanced manifestation of the disease, nonalcoholic steatohepatitis (NASH), increases the risk for both liver-related and cardiovascular morbidity. The pathogenesis of NAFLD is complex and multifactorial, with many molecular pathways implicated. Emerging data suggest that microsomal prostaglandin E synthase-1 and -2 might participate in the development and progression of NAFLD. It also appears that targeting these enzymes might represent a novel therapeutic approach for NAFLD. In the present review, we discuss the association between microsomal prostaglandin E synthase-1 and -2 and NAFLD.

The evolving role of checkpoint inhibitors in the treatment of urothelial carcinoma

The most prevalent pathological subtype of bladder and upper urinary tract malignancy is urothelial carcinoma (UC). Traditional therapies mainly include surgical resection, chemotherapy and radiotherapy. Checkpoint inhibitors, which are monoclonal antibodies developed to specifically target immune checkpoint molecules, have recently emerged as potential treatment options for UC patients, especially those targeting the programmed cell death protein 1 (PD-1) and its ligand (PD-L1). However, anti-PD-1/PD-L1 therapy does not work for a considerable number of UC patients. Current antitumour immunotherapy research hotspots include seeking biomarkers that might predict therapeutic effects and exploring novel immune checkpoint molecules crucial for the antitumour immune response. Hence, we will recapitulate the latest preclinical and clinical trials of 5 PD-1/PD-L1 inhibitors, 1 cytotoxic T-lymphocyte-associated protein 4 inhibitor and combination therapies for UC treatment, including combined immunotherapy and immunotherapy with chemotherapy or radiotherapy. We will also summarize other potential immune checkpoint molecules found in ongoing UC studies. Moreover, we will highlight the role of biomarkers linked with the oncological efficacy of anti-PD-1/PD-L1 immunotherapy and address the mechanisms of immunotherapy drug resistance in UC, with the hope of providing more systematic guidance for its application and development.

Therapeutic Potential of Targeting Transforming Growth Factor-beta (TGF-β) and Programmed Death-ligand 1 (PD-L1) in Pancreatic Cancer

Pancreatic cancer (PC) is one the most lethal malignancies worldwide affecting around half a million individuals each year. The treatment of PC is relatively difficult due to the difficulty in making an early diagnosis. Transforming growth factor-beta (TGF-β) is a multifunctional factor acting as both a tumor promoter in early cancer stages and a tumor suppressor in advanced disease. Programmed death-ligand 1 (PD-L1) is a ligand of programmed death-1 (PD-1), an immune checkpoint receptor, allowing tumor cells to avoid elimination by immune cells. Recently, targeting the TGF-β signaling and PD-L1 pathways has emerged as a strategy for cancer therapy. In this review, we have summarized the current knowledge regarding these pathways and their contribution to tumor development with a focus on PC. Moreover, we have reviewed the role of TGF-β and PD-L1 blockade in the treatment of various cancer types, including PC, and discussed the clinical trials evaluating TGF-β and PD-L1 antagonists in PC patients.

Monoclonal antibodies in cervical malignancy-related HPV

Despite many efforts to treat HPV infection, cervical cancer survival is still poor for several reasons, including resistance to chemotherapy and relapse. Numerous treatments such as surgery, radiation therapy, immune cell-based therapies, siRNA combined with various drugs, and immunotherapy are being studied and performed to provide the best treatment. Depending on the stage and size of the tumor, methods such as radical hysterectomy, pelvic lymphadenectomy, or chemotherapy can be utilized to treat cervical cancer. While accepted, these treatments lead to interruptions in cellular pathways and immune system homeostasis. In addition to a low survival rate, cervical neoplasm incidence has been rising significantly. However, new strategies have been proposed to increase patient survival while reducing the toxicity of chemotherapy, including targeted therapy and monoclonal antibodies. In this article, we discuss the types and potential therapeutic roles of monoclonal antibodies in cervical cancer.

Combination of Atezolizumab and Tazemetostat in Patients With Relapsed/Refractory Diffuse Large B-Cell Lymphoma: Results From a Phase Ib Study

BACKGROUND

The combination of atezolizumab, a monoclonal antibody that targets programmed death-ligand 1 (PD-L1) and inhibits the interaction between PD-L1 and its receptors, and tazemetostat, an EZH2 inhibitor, may lead to selective epigenetic reprogramming, alter the tumor microenvironment, and provide additive or synergistic response to patients with relapsed/refractory (R/R) diffuse large B-cell lymphoma (DLBCL).

MATERIALS AND METHODS

This was an open-label, phase Ib study assessing the safety, tolerability, and preliminary efficacy of atezolizumab plustazemetostat in patients with R/R DLBCL. Atezolizumab (1200 mg) was administered via intravenous (IV) infusion on day 1 of each cycle and tazemetostat (800 mg) was given orally twice daily (BID) on days 1 to 21. Primary endpoints were safety and tolerability, and to identify a recommended phase II dose (RP2D) for atezolizumab. Secondary efficacy endpoints included response rate and duration of response.

RESULTS

A total of 43 patients were enrolled, receiving a median of 3 prior lines of treatment (range: 1-9). The RP2D for atezolizumab was 1200 mg IV infusion every 3 weeks in combination with tazemetostat 800 mg BID. At the RP2D, adverse events reported in ≥20% patients were anemia(11 patients [26%]), fatigue (10 patients [23%]), and nausea (10 patients [23%]). Overall response rate was 16% (complete response rate: 7%). Median progression-free survival was 2 months (range: 0-24) and median overall survival was 13 months (range: 1-29).

CONCLUSIONS

The combination of atezolizumab and tazemetostat was determined to be safe and tolerable. However, anti-tumor activity of the combination was modest.

Advances in Diagnosis and Therapy for Bladder Cancer

Bladder cancer (BCa) is one of the most common and expensive urinary system malignancies for its high recurrence and progression rate. In recent years, immense amounts of studies have been carried out to bring a more comprehensive cognition and numerous promising clinic approaches for BCa therapy. The development of innovative enhanced cystoscopy techniques (optical techniques, imaging systems) and tumor biomarkers-based non-invasive urine screening (DNA methylation-based urine test) would dramatically improve the accuracy of tumor detection, reducing the risk of recurrence and progression of BCa. Moreover, intravesical instillation and systemic therapeutic strategies (cocktail therapy, immunotherapy, vaccine therapy, targeted therapy) also provide plentiful measures to break the predicament of BCa. Several exploratory clinical studies, including novel surgical approaches, pharmaceutical compositions, and bladder preservation techniques, emerged continually, which are supposed to be promising candidates for BCa clinical treatment. Here, recent advances and prospects of diagnosis, intravesical or systemic treatment, and novel drug delivery systems for BCa therapy are reviewed in this paper.

Insights on recent innovations in bladder cancer immunotherapy

Bladder carcinoma is the most common genitourinary cancer, with a high prevalence and global incidence. In addition to early detection by cytology, the management of bladder cancer has recently advanced, not only by improvements in conventional treatments such as surgery and chemotherapy, but also through the introduction of immunotherapeutic strategies. The number of approved immunotherapeutic agents has dramatically increased, with various preclinical and clinical applications in cancer drug discovery. Some bladder cancer immunotherapies include immune checkpoint inhibitors, adoptive cell therapy, cytokine-based therapy, bispecific antibodies, and antibody-drug conjugates. This review provides an overview of some of the innovative immunotherapeutic agents approved and in development that can potentially be used in the treatment of bladder cancer.

Optimal Sequential Predictive Probability Designs for Early-Phase Oncology Expansion Cohorts

PURPOSE

The customary approach to early-phase clinical trial design, where the focus is on identification of the maximum tolerated dose, is not always suitable for noncytotoxic or other targeted therapies. Many trials have continued to follow the 3 + 3 dose-escalation design, but with the addition of phase I dose-expansion cohorts to further characterize safety and assess efficacy. Dose-expansion cohorts are not always planned in advance nor rigorously designed. We introduce an approach to the design of phase I expansion cohorts on the basis of sequential predictive probability monitoring.

METHODS

Two optimization criteria are proposed that allow investigators to stop for futility to preserve limited resources while maintaining traditional control of type I and type II errors. We demonstrate the use of these designs through simulation, and we elucidate their implementation with a redesign of the phase I expansion cohort for atezolizumab in metastatic urothelial carcinoma.

RESULTS

A sequential predictive probability design outperforms Simon's two-stage designs and posterior probability monitoring with respect to both proposed optimization criteria. The Bayesian sequential predictive probability design yields increased power while significantly reducing the average sample size under the null hypothesis in the context of the case study, whereas the original study design yields too low type I error and power. The optimal efficiency design tended to have more desirable properties, subject to constraints on type I error and power, compared with the optimal accuracy design.

CONCLUSION

The optimal efficiency design allows investigators to preserve limited financial resources and to maintain ethical standards by halting potentially large dose-expansion cohorts early in the absence of promising efficacy results, while maintaining traditional control of type I and II error rates.

Tumor immunotherapies by immune checkpoint inhibitors (ICIs); the pros and cons

The main breakthrough in tumor immunotherapy was the discovery of immune checkpoint (IC) proteins, which act as a potent suppressor of the immune system by a myriad of mechanisms. After that, scientists focused on the immune checkpoint molecules mainly. Thereby, much effort was spent to progress novel strategies for suppressing these inhibitory axes, resulting in the evolution of immune checkpoint inhibitors (ICIs). Then, ICIs have become a promising approach and shaped a paradigm shift in tumor immunotherapies. CTLA-4 plays an influential role in attenuation of the induction of naïve and memory T cells by engagement with its responding ligands like B7-1 (CD80) and B7-2 (CD86). Besides, PD-1 is predominantly implicated in adjusting T cell function in peripheral tissues through its interaction with programmed death-ligand 1 (PD-L1) and PD-L2. Given their suppressive effects on anti-tumor immunity, it has firmly been documented that ICIs based therapies can be practical and rational therapeutic approaches to treat cancer patients. Nonetheless, tumor inherent or acquired resistance to ICI and some treatment-related toxicities restrict their application in the clinic. The current review will deliver a comprehensive overview of the ICI application to treat human tumors alone or in combination with other modalities to support more desired outcomes and lower toxicities in cancer patients. Video Abstract.

Immune Checkpoint Inhibitors Induced Hepatotoxicity; Gastroenterologists' Perspectives

BACKGROUND: Immune checkpoint inhibitors (ICIs) have promising clinical activity and are essential medications for patients with several malignancies. However, by deranging the immune system, these novel agents could lead to immune-related adverse events (IRAEs). Hepatotoxicity with checkpoint inhibitors usually results in acute hepatitis or drug-induced liver injury. METHODS: This review article discusses the recent clinical evidence available regarding checkpoint inhibitor-induced hepatitis and reviews an approach to their diagnosis and management. CONCLUSION: ICIs have improved patients' outcomes with different forms of malignancy; however, ICIs-related liver damage is a clinically significant entity in these patients. All patients should be monitored carefully for IRAEs while undergoing treatment with ICIs.

Phase II multicohort study of atezolizumab monotherapy in multiple advanced solid cancers

BACKGROUND

The programmed death-ligand 1 inhibitor atezolizumab had shown clinical activity against several advanced malignancies.

PATIENTS AND METHODS

This phase II, open-label basket study (NCT02458638) was conducted in 16 main cohorts of patients aged ≥18 years with stage III or IV solid tumors. In stage I, 12 patients were enrolled into each cohort. Treatment was atezolizumab 1200 mg intravenously every 3 weeks until loss of clinical benefit or unacceptable toxicity. The primary efficacy endpoint was the non-progression rate (NPR) at 18 weeks in treated, assessable patients. NPR ≤20% was not of interest for development as monotherapy, and NPR ≥40% was defined as the threshold of benefit/success. If ≥3 patients had non-progressive disease in stage I (interim analysis), 13 additional patients could be enrolled into stage II (final analysis). Secondary efficacy and safety endpoints were also evaluated.

RESULTS

Overall, 474 patients were enrolled and treated; 433 were included in the efficacy set. Due partly to slow recruitment because of competing trials and limited efficacy at interim analyses, enrollment was stopped early, including in cohorts that passed stage I boundaries of success. NPR was >20% in five cohorts: cervical cancer {n = 27; NPR 44.4% [95% confidence interval (CI) 25.5% to 64.7%]}; follicular/papillary thyroid cancer [n = 11; 54.5% (95% CI 23.4% to 83.3%)]; thymoma [n = 13; 76.9% (95% CI: 46.2% to 95.0%)]; gastroenteropancreatic (GEP) and lung neuroendocrine tumors [NETs; n = 24; 41.7% (95% CI 22.1% to 63.4%)], and low/intermediate grade carcinoid GEP and lung NETs [n = 12; 58.3% (95% CI 27.7% to 84.8%)]. Treatment-related adverse events occurred in 55.3% of patients overall, and at grade 3, 4, and 5 in 10.3%, 1.7%, and 0.4%, respectively.

CONCLUSIONS

Atezolizumab monotherapy was effective in the cervical cancer cohort. The interim benefit threshold was crossed in patients with follicular/papillary thyroid cancer, thymoma, and GEP and lung NETs, but recruitment was stopped before these signals could be confirmed in stage II. Safety was consistent with previous findings.

Immunological significance of alternative splicing prognostic signatures for bladder cancer

Background

Bladder cancer (BLCA) is the most common malignant tumor in the genitourinary system, and the complex tumor microenvironment (TME) of BLCA is the main factor in its difficult treatment. Accumulated evidence supports that alternative splicing (AS) events frequently occur in cancer and are closely related to the TME. Therefore, there is an urgent need to comprehensively analyze the prognostic value of AS events in BLCA.

Method

The clinical, transcriptome and AS data of BLCA were downloaded from the Cancer Genome Atlas database, and a Cox proportional hazard regression model and LASSO regression were used to establish a prognostic signature. Then, the prognostic value of the signature was verified by clinical survival status, clinicopathologic features, tumor immune microenvironment (TIME), and immune checkpoint. Next, we screened the AS-related genes with the largest expression differences between tumor and normal samples by gene differential expression analysis. Finally, the regulatory network of AS-splicing factors (SFs) was established to unravel the potential regulatory mechanism of AS events in BLCA.

Results

A BLCA prognostic signature related to seven AS events was constructed, and the prognostic value of the signature was also verified from multiple perspectives. Moreover, there was significant abnormal expression of PTGER3, a gene implicated in AS events, the expression of which was associated with the survival, clinicopathological features, TIME, and immunotherapy of BLCA, suggesting that it has potential clinical application value. Furthermore, the AS-SF regulatory network indicated that splicing factors (PRPF39, LUC7L, HSPA8 and DDX21) might be potential biomarkers of BLCA.

Conclusions

Our study revealed the potential role of AS events in the prognosis, TIME and immunotherapy of BLCA and yielded new insights into the molecular mechanisms of and personalized immunotherapy for BLCA.

Adverse Events of Immune Checkpoint Inhibitors Therapy for Urologic Cancer Patients in Clinical Trials: A Collaborative Systematic Review and Meta-analysis

CONTEXT

Therapies based on immune checkpoint inhibitors (ICIs) are transforming the treatment landscape of urologic oncology. Nevertheless, an exhaustive overview of the toxicity spectrum of these novel therapies has yet to be provided.

OBJECTIVE

To comprehensively investigate the incidence and profile of ICI therapy-related adverse events (AEs) across urologic cancers.

EVIDENCE ACQUISITION

We searched for all clinical trials investigating the role of ICI therapy published between January 2010 and September 2021. Studies involving urologic cancers with reported overall incidence or tabulated data of treatment-related AEs (trAEs) or immune-related AEs (irAEs) were included. A systematic review and meta-analysis was performed after protocol registration in PROSPERO (CRD42021276435).

EVIDENCE SYNTHESIS

We identified 2638 records, of which 92 studies (including 22942 participants) met the inclusion criteria. The pooled overall incidence was 81.6% (95% confidence interval [CI] 78.0-84.7) for any-grade trAEs and 29.3% (95% CI 24.9-34.1) for grade ≥3 trAEs. The pooled overall incidence was 34.3% (95% CI 28.5-40.7) for any-grade irAEs and 10.2% (95%CI 8.2-12.7) for grade ≥3 irAEs. On a multivariable analysis, cancer type, therapy combination, clinical settings (perioperative vs advanced/metastatic), and drug exposure were independently associated with the occurrence of trAEs or irAEs. The overall rate of treatment-related mortality was 0.94% (140 of 14 899 participants), with pneumonitis (9.3%), pneumonia (7.9%), and respiratory failure (7.1%) being the most common causes. Immune-related mortality occurred in 0.26% (28 of 10 723) patients, with pneumonitis (35.7%), hepatic failure (10.7%), and hepatitis (7.1%) being most common.

CONCLUSIONS

Our study provides a comprehensive overview of ICI-associated AEs in urologic cancer patients. The spectrum and incidence of AEs vary across cancer types, ICI types, clinical settings, and therapy combinations. These findings provide important guidance to clinicians in counseling and management of patients with urologic cancers.

PATIENT SUMMARY

A high proportion of patients experience immune checkpoint inhibitor-associated toxicity. Physician and patient education is critical for early recognition and proper management.

Safety and Antitumor Activity of α-PD-L1 Antibody as Monotherapy or in Combination with α-TIM-3 Antibody in Patients with Microsatellite Instability-High/Mismatch Repair-Deficient Tumors

PURPOSE

Immune checkpoint inhibitors show high response rates and durable clinical benefit in microsatellite instability-high/mismatch repair-deficient (MSI-H/dMMR) tumors. However, 50%-60% do not respond to single-agent anti-programmed death-1/programmed death ligand 1 (PD-1/PD-L1) antibodies, and approximately 50% of responders relapse within 6-12 months. This phase Ib trial evaluated safety and antitumor activity of anti-PD-L1 antibody LY3300054 monotherapy or in combination with anti-TIM-3 antibody LY3321367 in patients with MSI-H/dMMR advanced solid tumors.

PATIENTS AND METHODS

Eligible patients ≥18 years without prior anti-PD-1/PD-L1 therapy received LY3300054 monotherapy (N = 40) or combination (N = 20); patients with PD-1/PD-L1 inhibitor-resistant/refractory tumors received the combination (N = 22). LY3300054 (700 mg) and anti-TIM-3 antibody (cycles 1-2: 1,200 mg, cycle 3 onward: 600 mg) were administered intravenously every 2 weeks. Primary endpoints were safety and tolerability.

RESULTS

Eighty-two patients were enrolled. Most had colorectal (n = 39, 47.6%) or endometrial (n = 14, 17.1%) tumors. More than 70% of patients in the PD-1/PD-L1 inhibitor-resistant/refractory combination cohort had received ≥3 treatment lines. Treatment-related adverse events (TRAE) occurred in 22 patients (55.0%) receiving monotherapy, 13 (65.0%) in the PD-1/PD-L1 inhibitor-naïve combination cohort, and 6 (27.3%) in the PD-1/PD-L1 inhibitor-resistant/refractory combination cohort. A total of 2 patients (5.0%) receiving monotherapy and 3 (7.1%) receiving the combination experienced grade ≥3 TRAEs. Objective responses occurred in 13 patients (32.5%) with monotherapy, 9 (45.0%) in the PD-1/PD-L1 inhibitor-naïve combination cohort, and 1 patient (4.5%) in the PD-1/PD-L1 inhibitor-resistant/refractory combination cohort.

CONCLUSIONS

LY3300054 monotherapy and combined LY3300054/anti-TIM-3 had manageable safety profiles. Both regimens showed promising clinical activity against PD-1/PD-L1 inhibitor-naïve MSI-H/dMMR tumors. The combination had limited clinical benefit in patients with PD-1/PD-L1 inhibitor-resistant/refractory MSI-H/dMMR tumors.

Checkpoint Inhibition in Bladder Cancer: Clinical Expectations, Current Evidence, and Proposal of Future Strategies Based on a Tumor-Specific Immunobiological Approach

Simple Summary

In contrast with other strategies, immunotherapy is a treatment aimed at empowering the patient’s immune system in order to increase immunity and the response against cancer. Recently, a new class of drugs, immune checkpoint inhibitors, has shown potential in increasing treatment chances for patients with bladder cancers, improving their survival. However, predicting the response to immune checkpoint inhibition is important, since only a group of patients develop a good response. Biomarkers to predict the response to checkpoint inhibition must identify tumors’ and patients’ specific profiles. This study reviews the current knowledge on this most relevant clinical topic, focusing on bladder cancer, going from basic science to ongoing clinical trials and available clinical evidence. Finally, a critical analysis of published data is provided, and an original panel of biomarkers, able to select the right patients for treatments, based on patient-specific immune profiling, is proposed.

Abstract

In contrast with other strategies, immunotherapy is the only treatment aimed at empowering the immune system to increase the response against tumor growth. Immunotherapy has a role in the treatment of bladder cancer (BC) due to these tumors’ high tumor mutational burden (TMB) and mostly prominent immune infiltrate. The therapy or combination has to be adjusted to the tumor’s immunobiology. Recently, a new class of immunotherapeutic agents, immune checkpoint inhibitors (ICI), has shown potential in increasing treatment chances for patients with genitourinary cancers, improving their oncological outcomes. The clinical efficacy of ICI has been shown in both the first-line treatment of cisplatin-ineligible patients, with programmed death ligand 1 (PD-L1)-positive tumors (atezolizumab, pembrolizumab), and in second-line settings, for progression after platinum-based chemotherapy (atezolizumab, pembrolizumab, and nivolumab for FDA and EMA; durvalumab and avelumab for FDA alone). Predicting the response to ICI is important since only a subset of patients undergoing ICI therapy develop a concrete and lasting response. Most of the patients require a different therapy or therapy combination to achieve tumor control. The cancer immunity cycle provides a conceptual framework to assist therapy selection. Biomarkers to predict response to ICI must identify where the cancer immunity cycle is disrupted. We reviewed the current knowledge on ICI treatment in BC, going from basic science to current data and available clinical evidence. Secondly, a critical analysis of published data is provided, and an original panel of biomarkers able to predict response to ICI treatment, based on tumor-specific immune profiling, is proposed.

The efficacy and safety of PD-1/PD-L1 immune checkpoint inhibitors in treating advanced urothelial cancer: a meta-analysis of clinical trials

Survival outcomes in advanced urothelial cancer (UC) are dismal. Over the past years, immunotherapy remains an evolving treatment modality for these patients. This meta-analysis was performed to comprehensively evaluate the efficacy and safety of immune checkpoint inhibitors. For this purpose, 18 clinical trials comprising a total of 3,144 patients were identified from the PubMed database up to September 2020. Overall, the objective response rate (ORR) to PD-1/PD-L1 inhibitors was 0.20 [95% confidence intervals (CI) 0.17-0.23]. Furthermore, the pooled 1-year overall survival (OS) and 1-year progression-free survival (PFS) rates were 0.43 (95% CI 0.33-0.53) and 0.19 (95% CI 0.17-0.21), respectively. The summary rates of any-grade and grade ≥3 adverse events (AEs) were 0.66 (95% CI 0.58-0.74) and 0.13 (95% CI 0.09-0.18), respectively. Among the different subgroups, PD-1/PD-L1 inhibitors elicited a promising ORR in patients with lymph node-only metastasis compared to those with visceral metastasis (0.41 VS. 0.17). Additionally, patients with primary tumor in the lower tract had higher ORR compared to those with primary tumor in the upper tract (0.24 VS. 0.15). Briefly speaking, this immunotherapy protocol showed an encouraging efficacy and acceptable safety profile in the treatment of advanced UC. Moreover, our findings provided potential clinical significance for patients with lymph node-only metastasis or primary tumor in the lower tract. However, these exciting findings need further confirmation.

Identification of immune-related genes that predict prognosis and risk of bladder cancer: bioinformatics analysis of TCGA database

Background: Bladder cancer (BLCA) is the major tumor of the urinary system, and immune-related genes (IRGs) contribute significantly to its initiation and prognosis.

Results: A total of 51 prognostic IRGs significantly associated with overall survival were identified. Functional enrichment analysis revealed that these genes were actively involved in tumor-related functions and pathways. Using multivariate Cox regression analysis, we detected 11 optimal IRGs (ADIPOQ, PPY, NAMPT, TAP1, AHNAK, OLR1, PDGFRA, IL34, MMP9, RAC3, and SH3BP2). We validated the prognostic value of this signature in two validation cohorts: GSE13507 (n = 165) and GSE32894 (n = 224). Furthermore, we performed a western blot and found that the expression of these IRGs matched their mRNA expression in TCGA. Moreover, correlations between risk score and immune-cell infiltration indicated that the prognostic signature reflected infiltration by several types of immune cells.

Conclusion: We identified and validated an 11-IRG-based risk signature that may be a reliable tool to evaluate the prognosis of BLCA patients and help to devise individualized immunotherapies.

Methods: Bioinformatics analysis was performed using TCGA and ImmPort databases. Cox regression was used to identify prognostic signatures. Two external GEO cohorts and western blotting of samples were performed to validate the IRG signature.

PD-L1 detection on circulating tumor-derived extracellular vesicles (T-EVs) from patients with lung cancer

Background

Recent breakthroughs in therapies with immune checkpoint inhibitors (ICIs) have revolutionized the treatment of lung cancer. However, only 15–25% of patients respond to the ICIs therapy, and methods to identify those responsive patients are currently a hot research topic. PD-L1 expression measured on tumor tissues using immunohistochemistry (IHC) was approved as one of the companion diagnostic methods, but it is invasive and cannot be used to monitor dynamic changes in PD-L1 expression during treatments.

Methods

In this study, we developed an Epcam-PD-L1 extracellular vesicle (EV) detection prototype using the Simoa platform. This assay detected PD-L1 expression levels on tumor-derived exosomes from the lung cancer cell lines A549 and SK-MES1. In addition, 35 plasma samples from patients with lung cancer were tested with this assay and the results were compared to the tissue PD-L1 expression levels represented by the tumor proportion score (TPS).

Results

PD-L1 TPS-positive patients (≥1% IHC TPS) had significantly higher Simoa Epcam-PD-L1 signals than TPS-negative patients (<1% IHC TPS, P=0.026). The Simoa Epcam-PD-L1 area under curve (AUC) reached 0.776, with a sensitivity of 92.86% and a specificity of 71.43%. When PD-L1 TPS-positive patients were defined as having an IHC TPS ≥10%, the greatest difference in Epcam-PD-L1 signals was observed between IHC TPS-positive and IHC TPS-negative groups (P=0.0024) and the Simoa Epcam-PD-L1 AUC reached 0.832. Finally, the Spearman’s correlation coefficient showed a significant correlation between the TPS and Simoa Epcam-PD-L1 signals (0.428, P=0.0104).

Conclusions

Based on our results, our Simoa Epcam-PD-L1 EV detection assay is a potential liquid biopsy method to predict the PD-L1 expression level in patients with lung cancer.

Moving Beyond 3+3: The Future of Clinical Trial Design

Misgivings have been raised about the operating characteristics of the canonical 3+3 dose-escalation phase I clinical trial design. Yet, the traditional 3+3 design is still the most commonly used. Although it has been implied that adhering to this design is due to a stubborn reluctance to adopt change despite other designs performing better in hypothetical computer-generated simulation models, the continued adherence to 3+3 dose-escalation phase I strategies is more likely because these designs perform the best in the real world, pinpointing the correct dose and important side effects with an acceptable degree of precision. Beyond statistical simulations, there are little data to refute the supposed shortcomings ascribed to the 3+3 method. Even so, to address the unique nuances of gene- and immune-targeted compounds, a variety of inventive phase 1 trial designs have been suggested. Strategies for developing these therapies have launched first-in-human studies devised to acquire a breadth of patient data that far exceed the size of a typical phase I design and blur the distinction between dose selection and efficacy evaluation. Recent phase I trials of promising cancer therapies assessed objective tumor response and durability at various doses and schedules as well as incorporated multiple expansion cohorts spanning a variety of histology or biomarker-defined tumor subtypes, sometimes resulting in U.S. Food and Drug Administration approval after phase I. This article reviews recent innovations in phase I design from the perspective of multiple stakeholders and provides recommendations for future trials.

Treatment-Related Serious Adverse Events of Immune Checkpoint Inhibitors in Clinical Trials: A Systematic Review

Background

Immune Checkpoint Inhibitors (ICI) have been progressively used in cancer treatment and produced unique toxicity profiles. This systematic review aims to comprehend the patterns and occurrence of treatment-related adverse events (trAEs) based on ICI.

Methods

PICOS/PRISMA methods were used to identify published English-language on PubMed, Web of Science, and Scopus from 2015 to 2020. Published clinical trials on ICI monotherapy, combined ICIs, and ICI plus other treatment with tabulated data on grade≥3 trAEs were included. Odds ratio (OR), χ² tests were used to analyze for effect size and associations.

Results

This review included 145 clinical trials involving 21786 patients. Grade 3-5 trAEs were more common with ICI when they were plused with other treatments compared with ICI monotherapy(54.3% versus 17.7%, 46.1%, p<0.05). Grade 3-5 trAEs were also more common with CTLA-4 mAbs compared with anti-PD-1 and anti-PD-L1 (34.2% versus 15.1%, 13.6%, p<0.05). Hyperthyroidism (OR 3.8, 95%CI 1.7–8.6), nausea (OR 3.7, 95%CI 2.5–5.3), diarrhea (OR 2.7, 95%CI 2.2–3.2), colitis (OR 3.4, 95%CI 2.7–4.3), ALT increase (OR 4.9, 95%CI 3.9–6.1), AST increase (OR 3.8, 95%CI 3.0–4.9), pruritus (OR 2.4, 95%CI 1.5–3.9), rash (OR 2.8, 95%CI 2.1–3.8), fatigue (OR 2.8, 95%CI 2.2–3.7), decreased appetite (OR 2.4, 95%CI 1.5–3.8), and hypophysitis (OR 2.0, 95%CI 1.2–3.3) were more frequent with combined ICIs. Diarrhea (OR 8.1, 95%CI 6.4–10.3), colitis (OR 12.2, 95%CI 8.7–17.1), ALT increase (OR 5.1, 95%CI 3.5–7.4), AST increase (OR 4.2, 95%CI 2.8–6.3), pruritus (OR 4.1, 95%CI 2.0–8.4), rash (OR 4.4, 95%CI 2.9–6.8), hypophysitis (OR 12.1, 95%CI 6.3–23.4) were more common with CTLA-4 mAbs; whereas pneumonitis (OR 4.7, 95% CI 2.1–10.3) were more frequent with PD-1 mAbs.

Conclusions

Different immune checkpoint inhibitors are associated with different treatment-related adverse events profiles. A comprehensive data in this systematic review will provide comprehensive information for clinicians.

Time-dependent population PK models of single-agent atezolizumab in patients with cancer

PURPOSE

The time-varying clearance (CL) of the PD-L1 inhibitor atezolizumab was assessed on a population of 1519 cancer patients (primarily with non-small-cell lung cancer or metastatic urothelial carcinoma) from three clinical studies.

METHODS

The first step was to identify the baseline covariates affecting atezolizumab CL without including time-varying components (stationary covariate model). Two time-varying models were then investigated: (1) a model allowing baseline covariates to vary over time (time-varying covariate model), (2) a model with empirical time-varying Emax CL function.

RESULTS

The final stationary covariate model included main effects of body weight, albumin levels, tumor size, anti-drug antibodies (ADA) and gender on atezolizumab CL. Both time-varying models resulted in a clear improvement of the data fit and visual predictive checks over the stationary model. The time-varying covariate model provided the best fit of the data. In this model, the main driver for change in CL over time was variations in albumin level with an increase in serum albumin (improvement in a patient's status) mirroring a decrease in CL. Time-varying ADAs had a small impact (9% increase in CL). None of the covariates impacted atezolizumab CL by more than ± 30% from median. The estimated maximum decrease in CL with time was 22% with the Emax model.

CONCLUSION

The overall impact of covariates on atezolizumab CL did not warrant any change in atezolizumab dosing recommendations. The results support the hypothesis that variation in atezolizumab CL over time is associated with patients' disease status, as shown with other checkpoint inhibitors.

Response Efficacy of PD-1 and PD-L1 Inhibitors in Clinical Trials: A Systematic Review and Meta-Analysis

Background

Immune checkpoint inhibitors targeting the PD-1/PD-L1 pathway have demonstrated promise in treating a variety of advanced cancers; however, little is known regarding their efficacy under various clinical situations, including different cancer types, treatment lines, drug combinations, and therapeutic regimens.

Methods

Published articles and conference abstracts (in English) in PubMed, Embase, the Cochrane Central Register, and Web of Science were searched up to February 10, 2020. The data were analyzed by the meta-analysis program in Stata.

Results

A total of 16,400 patients from 91 clinical trials were included in this meta-analysis. PD-1/PD-L1 inhibitors had a mean ORR of 19.56% (95% CI: 15.09–24.03), a median TTR of 2.05 months (m) (95%CI: 1.85–2.26), and a median DOR of 10.65 m (95%CI: 7.78–13.52). First-line treatment had a higher ORR (36.57% vs. 13.18%) but a shorter DOR (9.00 m vs. 13.42 m) compared to the second-line or subsequent treatment. Immunotherapy combined with chemotherapy (I+C) (46.81% [95%CI: 36.02–57.60]) had a statistically significant higher ORR compared to immunotherapy (I) (17.75% [95%CI: 14.47–21.03]) or immunotherapy combined with immunotherapy (I+O) (12.25% [95%CI: 1.56–22.94]), while I+C (8.09 m [95%CI: 6.86–9.32]) appeared to reduce the DOR compared to I (12.39 m [95%CI: 7.60–17.18]). PD-1 inhibitors were associated with better ORR (21.65% vs. 17.60%) and DOR (11.26 m vs. 10.03 m) compared to PD-L1 inhibitors. There were no significant differences in TTR under different situations.

Conclusions

PD-1/PD-L1 inhibitors were promising immunotherapeutic agents to achieve satisfactory response efficacies with different cancer types, treatment lines, drug combinations, and therapeutic regimens. This comprehensive summary of the response efficacy of PD-1/PD-L1 inhibitors serves as a reference for clinicians to make evidence-based decisions.

Safety and Activity of Programmed Cell Death 1 Versus Programmed Cell Death Ligand 1 Inhibitors for Platinum-Resistant Urothelial Cancer: A Meta-Analysis of Published Clinical Trials

Background

Programmed death 1/ligand 1 (PD-1/L1) inhibitors have acceptable antitumor activity in patients with platinum-resistant urothelial cancer (UC). However, the reliability and comparability of the antitumor activity, safety profiles and survival outcomes of different immune checkpoint inhibitors are unknown. Our objective was to compare the clinical efficacy and safety of anti–PD-1/PD-L1 therapies in platinum-resistant UC patients.

Methods

We reviewed the published trials from the PubMed, Embase and Cochrane Library databases up to August 2020. A well-designed mirror principle strategy to screen and pair trial characteristics was used to justify indirect comparisons. The primary end point was the objective response rate (ORR). The safety profile and survival outcomes were also evaluated. The restricted mean survival time (RMST) up to 12 months was calculated.

Results

Eight studies including 1,666 advanced or metastatic UC patients (1,021 patients with anti–PD-L1 treatment and 645 patients with anti–PD-1 treatment) met the study criteria. The ORRs of anti–PD-1 and PD-L1 therapy were 22% (95% CI, 18%–25%) and 15% (95% CI, 13%–17%) with all studies combined. The proportions of the treated population with a confirmed objective response (I² = 0; P = 0.966; HR, 1.60; 95% CI, 1.23–2.07; P < 0.001) and disease control (I² = 30.6%; P = 0.229; HR, 1.35; 95% CI, 1.10–1.66; P = 0.004) were higher with anti–PD-1 therapy than with anti–PD-L1 therapy. The treatment-related adverse events (AEs) (I² = 78.3%; P = 0.003; OR, 1.09; 95% CI, 0.65–1.84; P = 0.741) and grade 3–5 treatment-related AEs (I² = 68.5%; P = 0.023; OR, 1.69; 95% CI, 0.95–3.01; P = 0.074) of anti–PD-1 therapy were comparable to those of anti–PD-L1 therapy. The RMST values at the 12-month follow-up were 9.4 months (95% CI,: 8.8–10.0) for anti–PD-1 therapy and 9.3 months (95% CI, 8.8–9.7) for anti–PD-L1 therapy (z = 0.26, P = 0.794). There was no significant difference between patients in the anti–PD-1 and anti–PD-L1 groups (12-month overall survival (OS): 43% versus 42%, P = 0.765. I² = 0; P = 0.999; HR, 0.95; 95% CI, 0.83–1.09; P = 0.474).

Conclusions

The results of our systematic comparison suggest that anti–PD-1 therapy exhibits better antitumor activity than anti–PD-L1 therapy, with comparable safety profiles and survival outcomes. These findings may contribute to enhanced treatment awareness in patients with platinum-resistant UC.

The Mechanisms Leading to Distinct Responses to PD-1/PD-L1 Blockades in Colorectal Cancers With Different MSI Statuses

Current clinical studies showed distinct therapeutic outcomes, in which CRC patients with mismatch repair-deficient (dMMR)/microsatellite instability high (MSI-H) seem to be relatively more "sensitive" in response to anti-programmed death-1 receptor (PD-1)/programmed death-1 receptor ligand 1 (PD-L1) therapy than those with mismatch repair-proficient (pMMR)/microsatellite instability-low (MSI-L). The mechanisms by which the same PD-1/PD-L1 blockades lead to two distinct therapeutic responses in CRC patients with different MSI statuses remain poorly understood and become a topic of great interest in both basic research and clinical practice. In this review of the potential mechanisms for the distinct response to PD-1/PD-L1 blockades between dMMR/MSI-H CRCs and pMMR/MSI-L CRCs, relevant references were electronically searched and collected from databases PubMed, MEDLINE, and Google scholar. Sixty-eight articles with full text and 10 articles by reference-cross search were included for final analysis after eligibility selection according to the guidelines of PRISMA. Analysis revealed that multiple factors e.g. tumor mutation burden, immune cell densities and types in the tumor microenvironment, expression levels of PD-1/PD-L1 and cytokines are potential determinants of such distinct response to PD-1/PD-L1 blockades in CRC patients with different MSI statuses which might help clinicians to select candidates for anti-PD-1/PD-L1 therapy and improve therapeutic response in patients with CRC.

Efficacy of immune-checkpoint inhibitors in PD-L1 selected or unselected patients vs. control group in patients with advanced or metastatic urothelial carcinoma

Most patients with advanced or metastatic urothelial carcinoma do not benefit significantly from Immune checkpoint inhibitors (ICIs) use. A systematic review and meta-analysis of randomized controlled trials to assess the efficacy and activity of ICIs, in terms of Overall Survival (OS), Progression-free survival (PFS), and Objective Response Rate (ORR). We systematically searched for articles from PubMed, Cochrane Library, Embase, and Web of science from their inception to December 1, 2020 with no language restrictions. The search was performed to identify all clinical trials (phase I, phase II, phase III) of ICIs for treating urothelial carcinoma. The endpoints of the meta-analysis were OS, PFS, and ORR, compared unselected patients and in the subgroup of patients characterized by high expression of PD-L1 (PD-L1 selected patients). Sixteen studies comprising 5559 patients were identified, of which data for OS comparison were available from 4 RCTs (2342 patients), two studies for PFS (649 patients), and four RCTs were eligible for ORR analysis (2921 patients). Both pembrolizumab and atezolizumab have showed to improve OS compared to chemotherapy in unselected patients (HR 0.86, 95% CI 0.80-0.93, P = .0001, I2 = 60%), while the difference was not significant in PD-L1 selected patients (HR 0.91, 95% CI 0.77-1.07, P = .23, I2 = 0%). PFS difference was not observed in neither unselected population nor PD-L1 selected patients, the pooled HR of PFS for immunotherapy compared to control treatment was 1.05 (95% CI 0.74-1.49, P = .79, I2 = 85%) and 0.84 (95% CI 0.68-1.03, P = .09, I2 = 0%, respectively. Similar result was observed in ORR, the pooled HR of ORR for immunotherapy compared to control treatment was 1.45 (95% CI 0.53-3.98, P = .47, I2 = 95%) and 2.19 (95% CI 0.79-6.08, P = .13, I2 = 83%), respectively. Immunotherapy could significantly improve survival advantage in unselected patients but not in PD-L1 selected population, indicating that PD-L1 expression may not be a reliable marker in previously platinum-treated patients.

Tumor Microenvironment Analysis Identified Subtypes Associated With the Prognosis and the Tumor Response to Immunotherapy in Bladder Cancer

Background: The efficiency of immune checkpoint inhibitors (ICIs) in bladder cancer (BLCA) treatment has been widely validated; however, the tumor response to ICIs was generally low. It is critical and urgent to find biomarkers that can predict tumor response to ICIs. The tumor microenvironment (TME), which may play important roles to either dampen or enhance immune responses, has been widely concerned. Methods: The cancer genome atlas BLCA (TCGA-BLCA) cohort (n = 400) was used in this study. Based on the proportions of 22 types of immune cells calculated by CIBERSORT, TME was classified by K-means Clustering and differentially expressed genes (DEGs) were determined. Based on DEGs, patients were classified into three groups, and cluster signature genes were identified after reducing redundant genes. Then TMEscore was calculated based on cluster signature genes, and the samples were classified to two subtypes. We performed somatic mutation and copy number variation analysis to identify the genetic characteristics of the two subtypes. Correlation analysis was performed to explore the correlation between TMEscore and the tumor response to ICIs as well as the prognosis of BLCA. Results: According to the proportions of immune cells, two TME clusters were determined, and 1,144 DEGs and 138 cluster signature genes were identified. Based on cluster signature genes, samples were classified into TMEscore-high (n = 199) and TMEscore-low (n = 201) subtypes. Survival analysis showed patients with TMEscore-high phenotype had better prognosis. Among the 45 differentially expressed micro-RNAs (miRNAs) and 1,033 differentially expressed messenger RNAs (mRNAs) between the two subtypes, 16 miRNAs and 287 mRNAs had statistically significant impact on the prognosis of BLCA. Furthermore, there were 94 genes with significant differences between the two subtypes, and they were enriched in RTK-RAS, NOTCH, WNT, Hippo, and PI3K pathways. The Tumor Immune Dysfunction and Exclusion (TIDE) score of TMEscore-high BLCA was statistically lower than that of TMEscore-low BLCA. Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) of TMEscore and tumor mutation burden (TMB) is 0.6918 and 0.5374, respectively. Conclusion: We developed a method to classify BLCA patients to two TME subtypes, TMEscore-high and TMEscore-low, and we found TMEscore-high subtype of BLCA had a good prognosis and a good response to ICIs.

Safety and Clinical Activity of a New Anti-PD-L1 Antibody as Monotherapy or Combined with Targeted Therapy in Advanced Solid Tumors: The PACT Phase Ia/Ib Trial

PURPOSE

This phase Ia/Ib PACT study evaluated the safety, pharmacokinetics, pharmacodynamics, and antitumor activity of a new programmed cell death ligand 1 (PD-L1) inhibitor, LY3300054, as monotherapy or in combination with ramucirumab, abemaciclib, or merestinib (a type II MET kinase inhibitor) in patients with advanced, refractory solid tumors (NCT02791334).

PATIENTS AND METHODS

Patients were enrolled into cohorts of escalating LY3300054 dose (phase Ia) as monotherapy (N = 15) or combined with ramucirumab (N = 10), abemaciclib (N = 24), or merestinib (N = 12). The phase Ib dose expansion enrolled 8 patients with melanoma in the monotherapy arm and 12 patients with pancreatic cancer in the merestinib combination arm. Combination treatments were administered concurrently from day 1 of each cycle. A 14-day lead-in abemaciclib arm was also explored. Primary endpoints were dose-limiting toxicity (DLT) and safety.

RESULTS

Treatment-related adverse events included fatigue and nausea in the monotherapy arm (13% for each), hypothyroidism (30%) in the ramucirumab arm, diarrhea (54%) in the abemaciclib arm, and nausea (25%) in the merestinib arm. DLTs associated with hepatoxicity were observed in 3 of 4 patients in the abemaciclib lead-in cohorts. No DLTs or grade 3 or 4 hepatoxicity were reported in the concurrent abemaciclib arm. Pharmacokinetic characteristics were comparable with other PD-L1 inhibitors. One patient in each arm experienced a partial response per RECIST v1.1 lasting ≥7 months.

CONCLUSIONS

LY3300054 was well tolerated without unexpected safety concerns when administered alone or concurrently with ramucirumab, abemaciclib, or merestinib. Lead-in abemaciclib before combining with LY3300054 was not feasible due to hepatotoxicity. Durable clinical benefits were seen in all regimens.

Management of Clinically Regional Node-Positive Urothelial Carcinoma of the Bladder

PURPOSE OF REVIEW

Clinically regional node-positive (cN+) urothelial carcinoma of the bladder requires a multi-modal management approach amidst growing recognition that it represents a spectrum of disease. Herein, we review the contemporary evidence for the natural history, evaluation, and management of clinically regional node-positive urothelial carcinoma of the bladder, highlighting recent changes in lymph node staging.

RECENT FINDINGS

Despite advances in techniques, cross-sectional imaging remains relatively insensitive for the detection of lymph node metastases. Recent changes to nodal staging that distinguish between cN1, cN2-3, and non-regional lymph node metastases reflect an increasing understanding that node-positive disease is heterogeneous and its management must be individualized according to nodal staging. Systemic therapy remains the initial management strategy, either alone or in conjunction with radiotherapy, with choice and sequencing of agents extrapolated from studies of metastatic disease. Consolidative radical cystectomy is an option for patients with disease response to upfront systemic therapy, and several series demonstrate a subset of patients with favorable oncologic outcomes. The comparative effectiveness of radiotherapy and radical cystectomy as local therapy remains an important evidence gap. Future studies that identify predictive biomarkers will help inform optimal choice of systemic therapy. The management of clinically regional node-positive disease requires a multimodal approach comprising both systemic and local therapy, tailored to the patient and to disease response. While choice of systemic therapy will be informed by ongoing studies in patients with metastatic disease, including the elucidation of predictive biomarkers, the comparative effectiveness of local therapies remains an important evidence gap.

Outcome of patients with advanced upper tract urothelial carcinoma treated with immune checkpoint inhibitors: A systematic review and meta-analysis

BACKGROUND

Advanced upper tract urothelial carcinoma (UTUC) has different molecular and genetic features from the commonest carcinoma of the bladder, suggesting a possible different sensitivity to immune-checkpoint inhibitors (ICI).

METHODS

A systematic review and meta-analysis of all relevant clinical studies including advanced UTUC patients treated with ICI was conducted according to PRISMA guidelines.

RESULTS

Six prospective trials for a total 2537 patients, including 396 (15.6 %) with advanced UTUC, were eligible for the analysis. In UTUC patients, the pooled ORR was 21.2 % (95 % CI, 12.5 %-33.7 %); the risk of death was reduced by 24 % over the standard platinum-based chemotherapy, but this was not statistically significant (hazard ratio = 0.76; 95 % confidence interval, 0.41-1.40; p = 0.37, χ2 = 3.28, p = 0.07; I2 = 70 %).

CONCLUSIONS

The current evidence does not support a statistically significant effect from ICI over the standard treatment for advanced UTUC patients. Properly performed pre-planned subgroup analyses from randomized clinical trials are eagerly awaited.

Identification of a novel immune microenvironment signature predicting survival and therapeutic options for bladder cancer

Few studies have investigated the potential of tumor immune microenvironment genes as indicators of urinary bladder cancer. Here, we sought to establish an immune-related gene signature for determining prognosis and treatment options. We developed a ten-gene tumor immune microenvironment signature and evaluated its prognostic capacity on internal and external cohorts. Multivariate Cox regression and nomogram analyses revealed the prognostic risk model as an independent and effective indicator of prognosis. We observed lower proportions of CD8+ T cells, dendritic cells, regulatory T cells, higher proportions of macrophages and neutrophils in high UBC risk group. UBC tissues with high-risk score tend to exhibit high TP53 and RB1 mutation rates, high PD1/PD-L1 expression and poor-survival basal squamous subtypes, while those with low-risk score tend to have high FGFR3 mutation rates and luminal papillary subtypes. Unexpectedly, we found a highly significant positive correlation between glycolytic genes and risk score, highlighting metabolic competition in tumor ecosystem and potential therapeutic avenues. Our study thus revealed a tumor immune microenvironment signature for predicting prognostic and response to immune checkpoint inhibitors against bladder cancer. Prospective studies are required to further test the predictive capacity of this model.

Immune checkpoint inhibition in muscle-invasive and locally advanced bladder cancer

PURPOSE OF REVIEW

Immune-checkpoint inhibitors (CPIs) have been implemented in the treatment algorithm of metastatic urothelial cancer as they have shown higher and more sustained responses compared with conventional second-line chemotherapy. Recently, several clinical trials have reported on CPIs in earlier disease stages such as muscle-invasive bladder cancer (MIBC). This review summarizes ongoing clinical trials and results from early phase clinical trials in muscle invasive and locally advanced bladder cancer.

RECENT FINDINGS

In phase II clinical trials, neoadjuvant use of CPIs as mono and combination therapy, in patients with MIBC planned for radical cystectomy, has shown promising pathological complete response rates. Whether this will translate in survival benefit remains to be assessed. Combination of CPIs and conventional chemotherapy or other targeted agents promises to increase the efficacy of perioperative systemic therapy with potentially additive toxicities. Recently, preclinical models of combined trimodal therapy with CPIs delivered the proof of principle leading to several ongoing trials in this setting.

SUMMARY

First results of clinical trials evaluating CPIs in MIBC demonstrate very promising results that warrant further investigation as they could revolutionize management of MIBC in the near future. The trend and hope are toward higher rates of safe and sustained bladder preservation.

Expression of PD-L1 for predicting response to immune checkpoint inhibitors in metastatic urothelial carcinoma: a systematic review and meta-analysis

Background

We conducted this meta-analysis and systematic literature review to study the ability of PD-L1 to predict objective response in patients with urothelial cancer treated with PD-1/PD-L1 inhibitors.

Methods

Relevant studies of PD-1 or PD-L1 inhibitors in urothelial cancer that reported objective response rate (orr) based on PD-L1 expression status in PubMed, embase, and the Cochrane Library were retrieved. Efficacy of PD-L1 expression status in predicting orr and the efficacy, safety of PD-1 and PD-L1 drugs were analyzed.

Results

Studies were divided into ≥1%, ≥5%, and ≥25% based on PD-L1 positivity threshold, and the patients were grouped into PD-L1 positive and negative. In all 3 expression thresholds, patients with positive PD-L1 expression were more likely to experience an objective response [≥1% threshold odds ratio (or): 1.74; 95% confidence interval (ci): 1.20 to 2.53; ≥5% threshold or: 2.74; 95% ci: 2.01 to 3.724; ≥25% threshold or: 7.13; 95% ci: 2.38 to 21.40] in comparison with patients with negative PD-L1 expression. Of the 3 thresholds, the ≥25% threshold was better in predicting orr (1.74 vs. 2.93 vs. 7.13; p < 0.0001). The ≥1% PD-L1 threshold had a relatively high sensitivity in predicting orr; the ≥5% PD-L1 threshold was better for specificity. Sensitivity was higher at the ≥25% threshold than at the other two thresholds, but specificity was lower. Further, we found that there is no statistically significant difference in efficacy between PD-1 and PD-L1 drugs.

Conclusions

Urothelial cancer patients with PD-L1 positive expression responded better than PD-L1 negative patients did, and a threshold of ≥5% or greater for PD-L1 expression might predict positive clinical response.

The Extrinsic and Intrinsic Roles of PD-L1 and Its Receptor PD-1: Implications for Immunotherapy Treatment

Programmed death-ligand 1 (PD-L1) is an immune checkpoint inhibitor that binds to its receptor PD-1 expressed by T cells and other immune cells to regulate immune responses; ultimately preventing exacerbated activation and autoimmunity. Many tumors exploit this mechanism by overexpressing PD-L1 which often correlates with poor prognosis. Some tumors have also recently been shown to express PD-1. On tumors, PD-L1 binding to PD-1 on immune cells promotes immune evasion and tumor progression, primarily by inhibition of cytotoxic T lymphocyte effector function. PD-1/PD-L1-targeted therapy has revolutionized the cancer therapy landscape and has become the first-line treatment for some cancers, due to their ability to promote durable anti-tumor immune responses in select patients with advanced cancers. Despite this clinical success, some patients have shown to be unresponsive, hyperprogressive or develop resistance to PD-1/PD-L1-targeted therapy. The exact mechanisms for this are still unclear. This review will discuss the current status of PD-1/PD-L1-targeted therapy, oncogenic expression of PD-L1, the new and emerging tumor-intrinisic roles of PD-L1 and its receptor PD-1 and how they may contribute to tumor progression and immunotherapy responses as shown in different oncology models.

Metastatic sites as predictors in advanced NSCLC treated with PD-1 inhibitors: a systematic review and meta-analysis

BACKGROUND

Programmed cell death protein 1 (PD-1) inhibitors are the first-line treatment for advanced non-small-cell lung cancer (NSCLC) patients. However, their efficacy in metastatic NSCLC patients remains controversial.

AIM OF THE STUDY

The aim of our study was to evaluate the prognosis of advanced metastatic NSCLC patients treated with PD-1 inhibitors, and discuss the predictive effect of metastatic site on the long-term outcome.

METHODS

The Embase, Ovid Medline, Cochrane Central Register of Controlled Trials, and PubMed databases were systematically screened up to February 10, 2020. Twenty-five eligible studies, involving 8,067 patients that assessed the impact of metastatic sites on survival outcome were incorporated in our study. Overall survival (OS) and progression-free survival (PFS) were described as hazard ratio (HR) with 95% confidence interval (CI).

RESULTS

Among the advanced NSCLC patients, the median proportion of brain, liver, bone, and adrenal gland metastases were 21%, 17%, 35%, and 21%, respectively. Patients with metastases to the brain, liver, and bone had worse OS compared to patients without these metastases when treated with PD-1 inhibitors. Similarly, patients with metastasis to the brain and liver were more likely to progress when treated with PD-1 inhibitors. Besides, patients with multiple metastatic sites had worse PFS compared to patients with one metastatic site, while no significant difference was found in terms of OS.

CONCLUSIONS

Based on the findings of our systematic review and meta-analysis, metastatic sites were independent predictors of the survival outcome for advanced NSCLC patients treated with PD-1 inhibitors.

Combined radiotherapy and immunotherapy in urothelial bladder cancer: harnessing the full potential of the anti-tumor immune response

PURPOSE

Radiotherapy (RT), as part of trimodal therapy, is an attractive alternative treatment in patients with urothelial muscle-invasive bladder cancer (MIBC). There is accumulating evidence suggesting the immunomodulatory effects of RT and its potential synergy when combined with immunotherapy. The aim of this review was to report on the most recent advances on this combination, including the mechanisms of RT immunomodulation, practical approach to combining RT and immunotherapy, and ongoing clinical trials in bladder cancer.

METHODS

Using the PubMed database, we identified articles published between March 2004 and April 2020 on the combination of RT with immunotherapy in localized or metastatic MIBC. A search of the Clinicaltrials.gov and Clinicaltrialsregister.eu/ retrieved ongoing clinical trials on the topic as well.

RESULTS

Combination of RT with immunotherapy leads to immunogenic cell death and an increase in immune markers thus leading to improved tumor control. For localized MIBC, there are safety concerns related to the use of concurrent immunotherapy with hypofractionated RT, thus neoadjuvant or adjuvant immunotherapy is preferred. In the metastatic setting, the combination of multi-site RT with SBRT-like doses (≥ 6 Gy per fraction) and concurrent immunotherapy seems most efficacious at harnessing the abscopal effect. At least 25 clinical trials combining immunotherapy and RT in MIBC are currently ongoing and will answer pending questions on safety, efficacy, and practical considerations on RT scheduling, fractionation, and targets volumes.

CONCLUSION

RT has the potential to synergize with immunotherapy to improve oncological outcomes in patient with localized or metastatic MIBC. Clinical trials results are eagerly awaited.

Safety and efficacy of atezolizumab in patients with autoimmune disease: Subgroup analysis of the SAUL study in locally advanced/metastatic urinary tract carcinoma

AIM

Patients with pre-existing autoimmune disease (AID) are typically excluded from clinical trials of immune checkpoint inhibitors, and there are limited data on outcomes in this population. The single-arm international SAUL study of atezolizumab enrolled a broader 'real-world' patient population. We present outcomes in patients with a history of AID.

METHODS

Patients with locally advanced/metastatic urinary tract carcinoma received atezolizumab 1200 mg every 3 weeks until loss of clinical benefit or unacceptable toxicity. The primary end-point was safety. Overall survival (OS) was a secondary end-point. Subgroup analyses of AID patients were prespecified.

RESULTS

Thirty-five of 997 treated patients had AID at baseline, most commonly psoriasis (n = 15). Compared with non-AID patients, AID patients experienced numerically more adverse events (AEs) of special interest (46% versus 30%; grade ≥3 14% versus 6%) and treatment-related grade 3/4 AEs (26% versus 12%), but without relevant increases in treatment-related deaths (0% versus 1%) or AEs necessitating treatment discontinuation (9% versus 6%). Pre-existing AID worsened in four patients (11%; two flares in two patients); three of the six flares resolved, one was resolving, and two were unresolved. Efficacy was similar in AID and non-AID patients (median OS, 8.2 versus 8.8 months, respectively; median progression-free survival, 4.4 versus 2.2 months; disease control rate, 51% versus 39%).

CONCLUSIONS

In 35 atezolizumab-treated patients with pre-existing AID, incidences of special- interest and treatment-related AEs appeared acceptable. AEs were manageable, rarely requiring atezolizumab discontinuation. Treating these patients requires caution, but pre-existing AID does not preclude atezolizumab therapy.

TRIAL REGISTRATION

NCT02928406.

Different patterns of treatment-related adverse events of programmed cell death-1 and its ligand-1 inhibitors in different cancer types: A meta-analysis and systemic review of clinical trials

Programmed cell death receptor-1 and its ligand-1 (PD-1/PD-L1) inhibitors have been applied to many cancers, but the difference of treatment-related adverse events (AEs) across cancer types remains unknown. We performed a meta-analysis and systemic review to compare the incidences of commonly reported all-grade AEs across cancer types and found that the most frequent AEs were fatigue, rash/pruritus, loss of appetite/nausea and diarrhea. However, each cancer type also had its higher incidences of AEs involving a relevant system, such as melanoma with epidermal AEs (rash, diarrhea and enterocolitis), lung cancer with dyspnea and pneumonitis, digestive system cancers with amylase and lipase elevation; and renal cell and urothelial cancer with kidney injury (creatinine elevation and proteinuria). However, the incidence of hepatitis did not follow the pattern to show a difference. We did another comparison between PD-1 and PD-L1 inhibitors in lung cancer and urothelial cancer respectively, and found that the risk of most AEs did not differ much, except for more hypothyroidism in PD-1 inhibitors, and more kidney injury in PD-L1 inhibitors. Besides possible immunological mechanisms for treatment-related AEs, the influence of previous radiotherapy and the clinical characteristics of the diseases themselves should also be considered and is worth further investigation. With the result of this meta-analysis, clinicians could estimate the risk of certain AE in certain cancer type, to make treatment options and to customize monitor strategies.

Randomized phase III KEYNOTE-045 trial of pembrolizumab versus paclitaxel, docetaxel, or vinflunine in recurrent advanced urothelial cancer: results of >2 years of follow-up

Background

Novel second-line treatments are needed for patients with advanced urothelial cancer (UC). Interim analysis of the phase III KEYNOTE-045 study showed a superior overall survival (OS) benefit of pembrolizumab, a programmed death 1 inhibitor, versus chemotherapy in patients with advanced UC that progressed on platinum-based chemotherapy. Here we report the long-term safety and efficacy outcomes of KEYNOTE-045.

Patients and methods

Adult patients with histologically/cytologically confirmed UC whose disease progressed after first-line, platinum-containing chemotherapy were enrolled. Patients were randomly assigned 1 : 1 to receive pembrolizumab [200 mg every 3 weeks (Q3W)] or investigator’s choice of paclitaxel (175 mg/m² Q3W), docetaxel (75 mg/m² Q3W), or vinflunine (320 mg/m² Q3W). Primary end points were OS and progression-free survival (PFS) per Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST v1.1) by blinded independent central radiology review (BICR). A key secondary end point was objective response rate per RECIST v1.1 by BICR.

Results

A total of 542 patients were enrolled (pembrolizumab, n = 270; chemotherapy, n = 272). Median follow-up as of 26 October 2017 was 27.7 months. Median 1- and 2-year OS rates were higher with pembrolizumab (44.2% and 26.9%, respectively) than chemotherapy (29.8% and 14.3%, respectively). PFS rates did not differ between treatment arms; however, 1- and 2-year PFS rates were higher with pembrolizumab. The objective response rate was also higher with pembrolizumab (21.1% versus 11.0%). Median duration of response to pembrolizumab was not reached (range 1.6+ to 30.0+ months) versus chemotherapy (4.4 months; range 1.4+ to 29.9+ months). Pembrolizumab had lower rates of any grade (62.0% versus 90.6%) and grade ≥3 (16.5% versus 50.2%) treatment-related adverse events than chemotherapy.

Conclusions

Long-term results (>2 years’ follow-up) were consistent with those of previously reported analyses, demonstrating continued clinical benefit of pembrolizumab over chemotherapy for efficacy and safety for treatment of locally advanced/metastatic, platinum-refractory UC.

Trial registration

ClinicalTrials.gov: NCT02256436.

Efficacy of PD-1/PD-L1 blockade monotherapy in clinical trials

Background:

Inhibitors targeting programmed cell death 1 (PD-1) and programmed death-ligand 1 (PD-L1) have unprecedented effects in cancer treatment. However, the objective response rates (ORRs), progression-free survival (PFS), and overall survival (OS) of PD-1/PD-L1 blockade monotherapy have not been systematically evaluated.

Methods:

We searched Embase, PubMed, and Cochrane database from inception to July 2019 for prospective clinical trials on single-agent PD-1/PD-L1 antibodies (avelumab, atezolizumab, durvalumab, cemiplimab, pembrolizumab, and nivolumab) with information regarding ORR, PFS, and OS.

Results:

Totally, 28,304 patients from 160 perspective trials were included. Overall, 4747 responses occurred in 22,165 patients treated with PD-1/PD-L1 monotherapy [ORR, 20.21%; 95% confidence interval (CI), 18.34–22.15%]. Compared with conventional therapy, PD-1/PD-L1 blockade immunotherapy was associated with more tumor responses (odds ratio, 1.98; 95% CI, 1.52–2.57) and better OS [hazard ratio (HR), 0.75; 95% CI, 0.67–0.83]. The ORRs varied significantly across cancer types and PD-L1 expression status. Line of treatment, clinical phase and drug target also impacted the response rates in some tumors. A total of 2313 of 9494 PD-L1 positive patients (ORR, 24.39%; 95% CI, 22.29–26.54%) and 456 of 4215 PD-L1 negative patients (ORR, 10.34%; 95% CI, 8.67–12.14%) achieved responses. For PD-L1 negative patients, the ORR (odds ratio, 0.92; 95% CI, 0.70–1.20) and PFS (HR, 1.15; 95% CI, 0.87–1.51) associated with immunotherapy and conventional treatment were similar. However, PD-1/PD-L1 blockade monotherapy decreased the risk of death in both PD-L1 positive (HR, 0.66; 95% CI, 0.60–0.72) and PD-L1 negative (HR, 0.86; 95% CI, 0.74–0.99) patients compared with conventional therapy.

Conclusion:

The efficacies associated with PD-1/PD-L1 monotherapy vary significantly across cancer types and PD-L1 expression. This comprehensive summary of clinical benefit from immunotherapy in cancer patients provides an important guide for clinicians.

[Immunotherapies in non-muscle invasive bladder cancer: immunotherapies and NMIBC]

Local and systemic immunotherapies are used for the management of bladder cancer in daily practice. BCG has been administered for almost 40 years in patients with non-muscle invasive bladder cancer (NMIBC). Despite its efficacy, disease progression is observed in nearly 30% of patients. Given the antitumor activity of immune checkpoint inhibitors in metastatic setting, these therapies are currently investigated in NMIBC. Pembrolizumab is now approved by the Food and Drug Administration (FDA) for the treatment of patients with BCG-unresponsive, high-risk, NMIBC with carcinoma in situ with or without papillary tumors who are ineligible for or have not elected to undergo cystectomy. Several phase 3 trials are ongoing to investigate the efficacy of PD(L)1 inhibitors combined with BCG such as ALBAN study in France.