Safety and activity of pembrolizumab in patients with locally advanced or metastatic urothelial cancer (KEYNOTE-012): a non-randomised, open-label, phase 1b study

Expansion of tumor infiltrating lymphocytes (TIL) from bladder cancer

Advanced bladder cancer patients have limited therapeutic options resulting in a median overall survival (OS) between 12 and 15 months. Adoptive cell therapy (ACT) using tumor infiltrating lymphocytes (TIL) has been used successfully in treating patients with metastatic melanoma, resulting in a median OS of 52 months. In this study, we investigated the feasibility of expanding TIL from the tumors of bladder cancer patients. Primary bladder tumors and lymph node (LN) metastases were collected. Tumor specimens were minced into fragments, placed in individual wells of a 24-well plate, and propagated in high dose IL-2 for four weeks. Expanded TIL were phenotyped by flow cytometry and anti-tumor reactivity was assessed after co-culture with autologous tumor digest and IFN-gamma ELISA. Of the 28 transitional cell bladder or LN tumors collected, 14/20 (70%) primary tumors and all of the LN metastases demonstrated TIL expansion. Expanded TIL were predominantly CD3⁺ (median 63%, range 10-87%) with a median of 30% CD8 + T cells (range 5-70%). TIL secreted IFN-gamma in response to autologous tumor. Addition of agonisitic 4-1BB antibody improved TIL expansion from primary bladder tumors regardless of pre-treatment with chemotherapy. This study establishes the practical first step towards an autologous TIL therapy process for therapeutic testing in patients with bladder cancer.

Pembrolizumab monotherapy versus chemotherapy for treatment of advanced urothelial carcinoma with disease progression during or following platinum-containing chemotherapy. A Cochrane Rapid Review

BACKGROUND

The use of systemic immunotherapy targets is emerging as an important treatment option for metastatic urothelial carcinoma, particularly for patients who cannot tolerate or who fail cisplatin-based chemotherapy. One such target is the inhibition of the checkpoint protein programmed cell death-1 (PD-1) receptor and its ligand (PD-L1) by monoclonal antibodies.

OBJECTIVES

To assess the effects of pembrolizumab monotherapy versus chemotherapy for treatment of advanced urothelial carcinoma with disease progression during or following platinum-containing chemotherapy.

SEARCH METHODS

We performed a Cochrane Rapid Review, limiting our search to published studies in the English language. We searched databases of the medical literature, including the Cochrane Central Register of Controlled Trials and MEDLINE, as well as trial registries including ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP). Our search extended from January 2000 to June 2018.

SELECTION CRITERIA

We included randomised controlled trials except cross-over trials and cluster randomised trials. We excluded all other study designs. Participants included had locally advanced or metastatic urothelial carcinoma of the bladder, with disease progression during or following platinum-containing chemotherapy (synonymous with second-/third-/fourth-line therapy). This review focused on pembrolizumab (synonyms: MK-3475, lambrolizumab, Keytruda).

DATA COLLECTION AND ANALYSIS

Two review authors independently classified and abstracted data from the included study. The certainty of evidence was rated according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We identified one randomised controlled trial that included 542 participants, which compared the use of pembrolizumab monotherapy versus chemotherapy for the treatment of advanced urothelial carcinoma with disease progression during or following platinum-containing chemotherapy. Results were reported after a median follow-up of 14.1 months (range 9.9 to 22.1 months).Primary outcomesPembrolizumab probably reduces the risk of death from any cause (hazard ratio (HR) 0.73, 95% confidence interval (CI) 0.59 to 0.90; moderate certainty evidence). This corresponds to 115 fewer deaths (191 fewer to 38 fewer) per 1000 participants with pembrolizumab at 12 months. We downgraded the certainty of evidence one level for imprecision.Pembrolizumab may slightly improve quality of life (change from baseline to week 15 assessed with the Core Quality of Life Questionnaire; higher value reflects better quality of life; scale 0 to 100) with a mean difference (MD) of 9.05, 95% CI 4.61 to 13.50; low certainty evidence). We downgraded the certainty of evidence two levels for study limitations and imprecision.Secondary outcomesPembrolizumab may have little or no effect on disease progression (HR 0.98, 95% CI 0.81 to 1.19; low certainty evidence). This corresponds to three fewer patients (42 fewer to 24 more) whose disease progressed per 1000 participants at 12 months. We downgraded the certainty of evidence two levels for study limitations and imprecision.Pembrolizumab probably improves treatment response (based on complete or partial radiologic response) with a risk ratio (RR) of 1.85, 95% CI 1.24 to 2.77; moderate certainty evidence). This corresponds to 97 more respondents (27 more to 202 more) per 1000 participants with pembrolizumab. We downgraded the certainty of evidence one level for imprecision.Pembrolizumab may have little or no effect on treatment-related mortality (RR 0.96, 95% CI 0.24 to 3.79; low certainty evidence). This corresponds to one fewer (12 fewer to 44 more) treatment-related deaths per 1000 participants with pembrolizumab. We downgraded the certainty of evidence two levels for study limitations and imprecision.Pembrolizumab may have little or no effect on discontinuations due to adverse events (RR 0.66, 95% CI 0.39 to 1.10). This corresponds to 54 fewer discontinuations per 1000 participants (95% CI 79 fewer to 7 more). We downgraded the certainty of evidence for study limitations and imprecision.Pembrolizumab may reduce serious adverse events (RR 0.83, 95 CI 0.72 to 0.97; low certainty evidence). This corresponds to 107 fewer serious averse events per 1000 participants (95% CI 19 fewer to 176 fewer). We downgraded two levels for study limitations and imprecision.

AUTHORS' CONCLUSIONS

The use of pembrolizumab in men with advanced urothelial carcinoma with disease progression during or following platinum-containing chemotherapy probably improves overall survival when compared with chemotherapy alone. At 12 months follow-up about 70% of those in the chemotherapy group had died, compared with 59% of those treated with pembrolizumab. We are very uncertain about the effects of pembolizumab on quality of life. Pembolizumab may also improve treatment response rates, and reduce the risk of serious adverse events, but may make little or no difference to discontinuations of treatment due to adverse events. These conclusions are based on a single trial that was sponsored by the producer of pembrolizumab.

Immune-checkpoint inhibitors in previously treated patients with advanced or metastatic urothelial carcinoma: A systematic review and meta-analysis

Immunotherapy represents a new hope for patients with advanced urothelial carcinoma (UC). However, to date, only one of two randomized studies showed a clear survival advantage with these treatments. Aimed to investigate the role of immune-checkpoint inhibitors in patients with platinum progressed metastatic UC we performed a systematic review and meta-analysis of clinical trials to evaluate the efficacy and activity, in terms of Overall Survival (OS) and Objective Response Rate (ORR). Immune checkpoint inhibitors have showed to improve OS compared to chemotherapy in unselected patients (HR 0.80, 95% CI 0.69-0.93, p = 0.003), while the difference was not significant in patients selected for PD-L1 expression (HR 0.72, 95% CI 0.48-1.09, p = 0.12). Pooled probability of response was 0.18 (95% CI 0.16-0.20) in unselected patients and 0.27 (95% CI 0.25-0.32) in PD-L1 selected patients. Immunotherapy results in a significant survival advantage in PD-L1 unselected patients suggesting that PD-L1 expression may not be a reliable marker in previously platinum treated patients.

Immunotherapy Combinations and Sequences in Urothelial Cancer: Facts and Hopes

Immune checkpoint inhibitors (ICI) have emerged as a novel therapeutic strategy that achieves significant clinical benefit in several tumor types, including urothelial cancer. Overall, these agents have shown objective response rates of around 20% to 23%, which indicates that a significant proportion of patients do not benefit from immunotherapy when given as monotherapy. Moreover, despite an initial response to therapy and an improvement in the median duration of response compared with chemotherapy, still only half of the patients develop long-term maintained remissions. Active research is ongoing in several fields, aiming to increase the number of patients that benefit from ICI, and this research is largely based on the development of biomarkers for personalized immunotherapy and novel combinations of ICI with other agents. This article will review ongoing efforts to develop combinations of ICI with other therapeutic strategies in patients with urothelial cancer, including chemotherapy, targeted agents, other immunotherapy strategies, and radiotherapy.

From Clinical Trials to Real-life Clinical Practice: The Role of Immunotherapy with PD-1/PD-L1 Inhibitors in Advanced Urothelial Carcinoma

CONTEXT

A number of PD-1/PD-L1 inhibitors have recently been approved for use in patients with locally advanced or metastatic urothelial carcinoma (UC) on the basis of results from several clinical trials.

OBJECTIVE

To review the evidence from these trials and consider what it means for the use of these drugs in first-line and post-platinum settings in real-life clinical practice.

EVIDENCE ACQUISITION

PubMed was searched for full reports of clinical trials of single-agent PD-1/PD-L1 inhibitors in advanced UC. Twelve publications were included.

EVIDENCE SYNTHESIS

Responses to PD-1/PD-L1 inhibitors appear to be durable but are only achieved in 17-26% of patients. These drugs offer different toxicity and efficacy profiles to standard chemotherapy regimens. This should be considered when choosing a treatment strategy for each patient.

CONCLUSIONS

PD-1/PD-L1 inhibitors represent a major step forward in the management of advanced UC, although several questions remain regarding their optimal use in routine clinical practice. A validated predictive biomarker of response is yet to be defined, and this is perhaps the most significant unmet need for currently available drugs.

PATIENT SUMMARY

We reviewed the results from clinical trials that investigated how well certain types of anticancer drugs called PD-1/PD-L1 inhibitors worked in patients with bladder cancer. We found that more research is required to identify (1) the factors that might predict which patients with bladder cancer will respond to PD-1/PD-L1 inhibitors and (2) the optimum duration of treatment with these drugs.

Efficacy and safety of pembrolizumab in recurrent/metastatic head and neck squamous cell carcinoma: pooled analyses after long-term follow-up in KEYNOTE-012

BACKGROUND

Second-line treatment options for advanced head and neck squamous cell carcinoma (HNSCC) are limited. The phase Ib KEYNOTE-012 study evaluated the safety and the efficacy of pembrolizumab for the treatment of HNSCC after long-term follow-up.

METHODS

Multi-centre, non-randomised trial included two HNSCC cohorts (initial and expansion) in which 192 patients were eligible. Patients received pembrolizumab 10 mg/kg every 2 weeks (initial cohort; N = 60) or 200 mg every 3 weeks (expansion cohort; N = 132). Co-primary endpoints were safety and overall response rate (ORR; RECIST v1.1; central imaging vendor review).

RESULTS

Median follow-up was 9 months (range, 0.2-32). Treatment-related adverse events (AEs) of any grade and grade 3/4 occurred in 123 (64%) and 24 (13%) patients, respectively. No deaths were attributed to treatment-related AEs. ORR was 18% (34/192; 95% CI, 13-24%). Median response duration was not reached (range, 2+ to 30+ months); 85% of responses lasted ≥6 months. Overall survival at 12 months was 38%.

CONCLUSIONS

Some patients received 2 years of treatment and the responses were ongoing for more than 30 months; the durable anti-tumour activity and tolerable safety profile, observed with long-term follow-up, support the use of pembrolizumab as a treatment for recurrent/metastatic HNSCC.

Immune checkpoint inhibitors in urothelial cancer: recent updates and future outlook

Bladder cancer is the sixth most common cancer in the US and most tumors have urothelial (transitional cell) histology. Platinum-based chemotherapy has long been the standard of care in advanced disease, but long-term outcomes have largely remained poor. Since the peak incidence of bladder cancer is in the eighth decade of life and beyond, medical comorbidities may often limit the use of chemotherapy. Immune checkpoint inhibitors with their favorable toxicity profiles and notable antitumor activity have ushered in a new era in the treatment of advanced urothelial cancer (UC) with five agents targeting the PD-1/PD-L1 pathway being recently approved by the US Food and Drug administration. A plethora of clinical trials are ongoing in diverse disease settings, employing agents targeting PD-1/PD-L1 and related immune checkpoint pathways. While reactivating anti-tumor immunity, these agents may lead to a unique constellation of immune-related adverse events, which may warrant discontinuation of therapy and potential use of immunosuppression. Novel combinations with various treatment modalities and optimal sequencing of active therapies are being investigated in prospective clinical trials and retrospective registries. At the era of precision molecular medicine, and since patients do not respond uniformly to these agents, there is a growing need for identification and validation of biomarkers that can accurately predict treatment response and assist in patient selection. This review discusses current updates and future directions of immunotherapy in advanced UC.

Immune-related musculoskeletal toxicities among cancer patients treated with immune checkpoint inhibitors: a systematic review

AIM

Immune-related musculoskeletal toxicities are uncommon but potentially serious adverse events; and they may accompany the use of immune checkpoint inhibitors (ICIs). The objective of this systematic review is to assess the patterns of these musculoskeletal toxicities.

METHODS & RESULTS

PubMed database has been searched till May 2017. Clinical studies and case reports reporting the occurrence of immune-related musculoskeletal toxicities (other than arthralgia and myalgia) in cancer patients treated with ICIs were included. Eight trials with 2263 participants were included. Likewise, nine case reports reporting the outcomes of 12 patients were included.

CONCLUSION

Immune-related arthritis and myositis occur uncommonly in cancer patients treated with ICIs. Further studies are required to better describe the pathogenesis as well as the time course of these events.

PD-L2 amplification and durable disease stabilization in patient with urothelial carcinoma receiving pembrolizumab

We report the immunological profile of a patient with upper-tract urothelial carcinoma experiencing stable disease on pembrolizumab for 20 months. The tumor exhibited extensive infiltration by CD8⁺ cytotoxic T lymphocytes, low-to-moderate mutational burden, no PD-L1 staining by commercially available immunohistochemical assays, but amplification of CD274 (coding for PD-L1) and/or PDCD1LG2 (encoding PD-L2) by fluorescence in situ hybridization. RNA-seq revealed multiple biomarkers of an ongoing immune response and compensatory immune evasion, including moderate PD-L1 levels coupled with robust PD-L2 expression. Pending validation in additional patients, these findings suggest that PD-L2 expression levels may constitute a biomarker of response to immune checkpoint blockade in urothelial carcinoma.

Emerging intravesical drugs for the treatment of non muscle-invasive bladder cancer

INTRODUCTION

Bladder cancer (BC) is a severe health burden: and has high recurrence and progression rates. Standard treatment starts with TURB followed by intravesical chemotherapy with Mitomycin C or immunotherapy with BCG. However, successful management still remains a challenge, because approximately 30% of patients have recurrence or progression within 5 years, and treatment has considerable side effects. Anticipating on the upcoming BCG shortage emphasizes, moreover, the necessity to develop and study novel treatments. This review explores emerging and novel salvage treatments as well as approaches of current treatments with decrease side-effects for non muscle-invasive bladder cancer (NMIBC). Areas covered: In this review, the authors provide an overview of the novel and emerging therapies for NMIBC. They also provide the currently available data and ongoing trials. Expert opinion: Key findings in the field of research on emerging intravesical drugs for the treatment of NMIBC are the promising results for device assisted treatments, treatment with intravesical immunotherapy, and treatments to expedite the immunotherapy checkpoint inhibitors. Other novel therapies are still in an experimental stage and have to make the transition towards the clinical setting to determine the benefit in terms of reduced side-effects, recurrence and progression rates.

Safety and Efficacy of Pembrolizumab Monotherapy in Patients With Previously Treated Advanced Gastric and Gastroesophageal Junction Cancer: Phase 2 Clinical KEYNOTE-059 Trial

IMPORTANCE

Therapeutic options are needed for patients with advanced gastric cancer whose disease has progressed after 2 or more lines of therapy.

OBJECTIVE

To evaluate the safety and efficacy of pembrolizumab in a cohort of patients with previously treated gastric or gastroesophageal junction cancer.

DESIGN, SETTING, AND PARTICIPANTS

In the phase 2, global, open-label, single-arm, multicohort KEYNOTE-059 study, 259 patients in 16 countries were enrolled in a cohort between March 2, 2015, and May 26, 2016. Median (range) follow-up was 5.8 (0.5-21.6) months.

INTERVENTION

Patients received pembrolizumab, 200 mg, intravenously every 3 weeks until disease progression, investigator or patient decision to withdraw, or unacceptable toxic effects.

MAIN OUTCOMES AND MEASURES

Primary end points were objective response rate and safety. Objective response rate was assessed by central radiologic review per Response Evaluation Criteria in Solid Tumors, version 1.1, in all patients and those with programmed cell death 1 ligand 1 (PD-L1)-positive tumors. Expression of PD-L1 was assessed by immunohistochemistry. Secondary end points included response duration.

RESULTS

Of 259 patients enrolled, most were male (198 [76.4%]) and white (200 [77.2%]); median (range) age was 62 (24-89) years. Objective response rate was 11.6% (95% CI, 8.0%-16.1%; 30 of 259 patients), with complete response in 2.3% (95% CI, 0.9%-5.0%; 6 of 259 patients). Median (range) response duration was 8.4 (1.6+ to 17.3+) months (+ indicates that patients had no progressive disease at their last assessment). Objective response rate and median (range) response duration were 15.5% (95% CI, 10.1%-22.4%; 23 of 148 patients) and 16.3 (1.6+ to 17.3+) months and 6.4% (95% CI, 2.6%-12.8%; 7 of 109 patients) and 6.9 (2.4 to 7.0+) months in patients with PD-L1-positive and PD-L1-negative tumors, respectively. Forty-six patients (17.8%) experienced 1 or more grade 3 to 5 treatment-related adverse events. Two patients (0.8%) discontinued because of treatment-related adverse events, and 2 deaths were considered related to treatment.

CONCLUSIONS AND RELEVANCE

Pembrolizumab monotherapy demonstrated promising activity and manageable safety in patients with advanced gastric or gastroesophageal junction cancer who had previously received at least 2 lines of treatment. Durable responses were observed in patients with PD-L1-positive and PD-L1-negative tumors. Further study of pembrolizumab for this group of patients is warranted.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT02335411.

Long-term Survival After Treating Cardiac Metastasis With Radiation and Immune Therapy: A Case Report

Cardiac metastases are a rare clinical entity and they generally portend a poor prognosis. Management is generally directed toward symptom control and maintaining cardiac function; however, long-term survival is rare. Here, we report a case of isolated metastatic urothelial cell carcinoma to the right ventricle that was functionally limiting the patient. The metastasis was successfully palliated for 17 months following radiation and immune therapy; however, disease progression in and around his heart ultimately led to a cardiac arrest.

Programmed cell death-1 and programmed cell death ligand-1 antibodies-induced dysthyroidism

BACKGROUND

Monoclonal antibodies blocking the programmed cell death-1 (PD-1) or its ligand (PD-L1) are a group of immune checkpoints inhibitors (ICIs) with proven antitumor efficacy. However, their use is complicated by immune-related adverse events (irAEs), including endocrine adverse events (eAEs).

PURPOSE

We review the incidence, time to onset and resolution rate of dysthyroidism induced by PD-1/PD-L1 Ab, and the clinical, biological and radiological findings. We aim to discuss the potential mechanisms of PD-1/PD-L1 Ab-induced dysthyroidism, and to propose a management algorithm.

METHODS

We performed a literature search of available clinical trials regarding PD-1/PD-L1 Ab in the PubMed database. We selected all English language clinical trials that included at least 100 patients. We also present selected case series or reports, retrospective studies and reviews related to this issue.

FINDINGS

In patients treated with PD-1 Ab, hypothyroidism occurred in 2-10.1% and hyperthyroidism occurred in 0.9-7.8%. When thyroiditis was reported separately, it occurred in 0.34-2.6%. Higher rates were reported when PD-1 Ab were associated with other ICI or chemotherapy. The median time to onset of hyperthyroidism and hypothyroidism after PD-1 Ab initiation was 23-45 days and 2-3.5 months, respectively. Regarding PD-L1 Ab, hypothyroidism occurred in 0-10% and hyperthyroidism in 0.5-2% of treated patients. The average time to onset of dysthyroidism after PD-L1 Ab was variable and ranged from 1 day after treatment initiation to 31 months.

CONCLUSION

Dysthyroidism occurs in up to 10% of patients treated with PD-1/PD-L1 Ab. Hypothyroidism and reversible destructive thyroiditis are the most frequent endocrine adverse events (eAE) in PD-1/PD-L1 treated patients. Immune and non-immune mechanisms are potentially involved, independently of the presence of thyroid antibodies.

Clinical Role of Programmed Cell Death-1 Expression in Patients with Non-muscle-invasive Bladder Cancer Recurring After Initial Bacillus Calmette-Guérin Therapy

BACKGROUND

The programmed cell death-1 (PD-1) pathway has been suggested to play an important role in tumor immune escape. We evaluated changes in PD-1 expression before and after Bacillus Calmette-Guérin (BCG) therapy and its prognostic significance in non-muscle-invasive bladder cancer (NMIBC) patients.

METHODS

We examined 78 paired tissue samples of NMIBC in tumors just before BCG therapy and BCG-relapsing tumors, defined as recurrence after achieving disease-free status by initial BCG instillations for 6 months. We counted PD-1-positive cells, and PD-1 expression was defined as high when the number of PD-1-positive cells was more than 18 under ×200 magnification.

RESULTS

The median number of PD-1-positive cells in tumors just before BCG therapy was 3.5, significantly lower than that in BCG-relapsing tumors (17.0, p < 0.001). High PD-1 expression was observed in 20 tumors just before BCG therapy (25.6%) and 36 BCG-relapsing tumors (46.2%). Fifty-two cases (66.6%) showed an increase in the number of PD-1-positive cells in BCG-relapsing tumors. High PD-1 expression in BCG-relapsing tumors was independently associated with subsequent tumor recurrence (p = 0.011) and stage progression (p = 0.033). The 5-year recurrence-free and progression-free survival rates were 40.7 and 74.1% in patients with high PD-1 expression in BCG-relapsing tumors, significantly lower than those in their counterparts (72.9 and 94.1%, respectively).

CONCLUSIONS

PD-1 was induced by BCG therapy, and its expression in BCG-relapsing tumors may be an important indicator for predicting worse clinical outcomes in NMIBC patients treated with BCG therapy.

[Advanced bladder cancer : From chemo- to immunotherapy]

In November 2016, the results of a phase III clinical trial with the protein cell death (PD)-1 inhibitor pembrolizumab for second-line treatment of metastatic urothelial carcinoma were published and showed an overall survival benefit in comparison with conventional chemotherapy with vinflunine, docetaxel, or paclitaxel. In a similar trial the PD-L1 antibody atezolizumab showed no significant benefit in comparison to chemotherapy in the subgroup of PD-L1-positive patients and, thus, missed its primary endpoint. For other PD-1/PD-L1 directed substances, large phase I/II trials reported data concerning response rates and overall survival. This substance class will most likely become the new treatment standard in second-line treatment of metastatic urothelial cancer. Currently, PD-1/PD-L1 inhibitors are also being tested within randomized phase III trials for first-line treatment using different approaches either as a monotherapy or a combination with conventional chemotherapy or cytotoxic T‑lymphocyte-associated protein (CTLA)-4 inhibitors. Whereas data from single-arm phase II clinical trials have already been published, preliminary phase III data are expected in 2018.

Emerging Role of Immunotherapy in Advanced Urothelial Carcinoma

PURPOSE OF REVIEW

Advanced urothelial carcinoma (aUC) has long been treated preferably with cisplatin-based chemotherapy, but many patients are cisplatin-ineligible whereas for those who progress on a platinum-based regimen treatment options are limited. We review key recent data regarding immune checkpoint inhibitors that are changing this treatment landscape.

RECENT FINDINGS

Since May 2016, five different agents targeting the PD-1/PD-L1 pathway (atezolizumab, pembrolizumab, nivolumab, avelumab, durvalumab) have received FDA approval for the treatment of aUC in the platinum-refractory setting, while pembrolizumab and atezolizumab are FDA-approved for cisplatin-ineligible patients in the first-line setting. Clinical outcomes and safety profiles of these agents appear relatively comparable across separate trials; however, only pembrolizumab is supported by level I evidence from a large randomized phase III trial showing overall survival benefit over conventional cytotoxic salvage chemotherapy in the platinum-refractory setting. Pembrolizumab has the highest level of evidence in platinum-refractory aUC, whereas pembrolizumab and atezolizumab have comparable level of evidence in the frontline setting in cisplatin-ineligible patients. Ongoing research is evaluating novel agents, various rational combinations, and sequences, as well as predictive and prognostic biomarkers.

Immune checkpoint inhibitors in gastrointestinal malignancies

Gastrointestinal (GIT) tumors are extremely fatal and lethal tumors with limited therapeutic options. Antitumor immunity is new line of research in management of solid tumors. Immune check points are negative regulators of immune system and control the immune response. These checkpoints are exploited by cancer cells. Cancer cells causes early activation of checkpoints and suppress the immune response, and therefore have unchecked growth and metastasis of malignant cells. Immune checkpoint inhibitors (ICIs), downregulates these checkpoints and activate the proliferation of cytotoxic T cells which helps in lysis of tumor cells. ICIs have shown the promising results in management of melanoma, non-small cell lung cancer and renal cell carcinoma. Encouraged by their recent success in solid tumors many clinical trials are ongoing to evaluate their efficacy in GIT tumors. In this article we will try to explain rationale for use of ICIs in GIT tumors. We will summarize the ongoing research, preliminary results and future aspects of ICIs in GIT malignancies.

Anti-Programmed Cell Death 1/Ligand 1 (PD-1/PD-L1) Antibodies for the Treatment of Urothelial Carcinoma: State of the Art and Future Development

Immunotherapy with programmed cell death 1/ligand 1 (PD-1/PD-L1) checkpoint inhibitors has expanded a previously limited pool of effective treatment options for patients with metastatic urothelial carcinoma, particularly those with recurring or refractory disease and those who are ineligible for cisplatin. This review reports key findings from completed and ongoing clinical trials that highlight the potential of PD-1/PD-L1 blockade in urothelial carcinoma. A literature search was performed of PubMed, Embase, ClinicalTrials.gov, and selected annual congress abstracts. Prospective studies, reviews, editorials, and descriptions of ongoing anti-PD-1/PD-L1 studies in bladder cancer were included. Anti-PD-1/PD-L1 monoclonal antibodies have shown efficacy and safety across patient subgroups with urothelial carcinoma, including those with poor prognostic factors. Efficacy was similar across different anti-PD-1/PD-L1 agents. Although these antibodies have demonstrated durable responses in a subset of patients with urothelial carcinoma, clinicians are currently unable to predict which patients may derive benefit from immune checkpoint blockade. Anti-PD-1/PD-L1 antibodies have shown favorable clinical activity and tolerability in patients with metastatic urothelial carcinoma refractory to platinum-based therapy or who are ineligible for cisplatin. The activity of PD-1/PD-L1 inhibitors is now also being studied as first-line monotherapy in cisplatin-eligible patients in combination with chemotherapy as maintenance therapy after first-line chemotherapy, and in earlier disease states, such as muscle-invasive and non-muscle-invasive bladder cancer. Better predictive tools to define target patient populations are needed, as are further investigations to define optimal combinations or sequencing of treatments.

Health-Related Quality-of-Life Analysis From KEYNOTE-045: A Phase III Study of Pembrolizumab Versus Chemotherapy for Previously Treated Advanced Urothelial Cancer

Purpose In the phase III KEYNOTE-045 study ( ClinicalTrials.gov identifier: NCT02256436), pembrolizumab significantly prolonged overall survival compared with investigator's choice of chemotherapy in patients with previously treated advanced urothelial cancer. Here, we report the results of health-related quality-of-life (HRQoL) analyses from the KEYNOTE-045 trial. Patients and Methods Patients were randomly assigned 1:1 to pembrolizumab 200 mg or investigator's choice of docetaxel 75 mg/m², paclitaxel 175 mg/m², or vinflunine 320 mg/m² administered intravenously every 3 weeks. Key prespecified HRQoL analyses were time to deterioration (TTD) and mean change from baseline to week 15 in European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire C30 global health status/quality-of-life score. Results Of 542 patients who were randomly assigned, 519 were included in HRQoL analyses (pembrolizumab, n = 266; chemotherapy, n = 253). HRQoL compliance was > 95% at baseline and approximately 88% at week 15 for both groups. Pembrolizumab prolonged TTD in global health status/quality-of-life score compared with chemotherapy (median, 3.5 months v 2.3 months; hazard ratio, 0.72; nominal one-sided P = .004). Mean (95% CI) change from baseline to week 15 in global health status/quality-of-life score was 0.69 (-2.40 to 3.77) with pembrolizumab and -8.36 (-11.84 to -4.89) with chemotherapy (mean difference, 9.05 points; 95% CI, 4.61 to 13.50; nominal two-sided P < .001). Conclusion Pembrolizumab prolonged TTD in HRQoL compared with chemotherapy. Patients who were treated with pembrolizumab had stable or improved global health status/quality of life, whereas those who were treated with investigator's choice of chemotherapy experienced declines in global health status/quality of life. Combined with efficacy and safety outcomes, these data support pembrolizumab as standard of care for patients with platinum-refractory advanced urothelial cancer.

A novel monoclonal antibody KMP1 has potential antitumor activity of bladder cancer by blocking CD44 in vivo and in vitro

Bladder cancer becomes a serious medical and social concern due to its high recurrence and mortality rates. Thus, it is urgent to search a novel prognostic biomarker and targeted therapy with high sensitivity and specificity. In this study, we used the human bladder cancer cell line EJ as an immunogen to generate a novel mouse monoclonal antibody KMP1 that specifically bound to bladder cancer, and then, the antitumor effect of KMP1 against bladder cancer was investigated both in vivo and in vitro. The results showed that expression of the KMP1 epitope is consistent with clinical severity and prognosis of bladder cancer. Furthermore, KMP1 not only significantly inhibited the proliferation, migration, and adhesion of EJ cells in vivo, but also suppressed the xenograft tumor growth in nude mice compared with the control group treated with mIgG. Subsequently, the underlying mechanism of KMP1 against bladder cancer was explored via antigen affinity chromatography and mass spectrometry. CD44 located on the cytomembrane was found as the antigen of KMP1. Using RNA interference technology to knock down CD44 expression, we further identified that KMP1 has the antitumor activity by binding to CD44 and blocking its functions. In conclusion, KMP1 might be valuable for development as a promising specific diagnostic biomarker or targeted agent for bladder cancer.

Pembrolizumab in Asia-Pacific patients with advanced head and neck squamous cell carcinoma: Analyses from KEYNOTE-012

KEYNOTE-012 was a phase Ib, multicohort study designed to investigate efficacy and safety of pembrolizumab in advanced solid tumors. Results from the subset of patients with recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) from the Asia-Pacific region are reported. Patients with recurrent/metastatic HNSCC, measurable disease (RECIST version 1.1), and ECOG performance status (PS) 0-1 were eligible for enrollment in the HNSCC expansion cohort. Patients received pembrolizumab 200 mg every 3 weeks. Response was assessed every 8 weeks. Co-primary end-points were safety and overall response rate (RECIST version 1.1, central review). Secondary end-points included overall survival and response duration. Patients enrolled at any of the five centers throughout the Asia-Pacific region were included in these analyses. Twenty-six patients with HNSCC from the Asia-Pacific region received pembrolizumab. The median age was 62 years, 65% of patients had ECOG PS 1, and 62% had received two or more prior therapies for recurrent/metastatic disease. Sixteen (62%) patients experienced a treatment-related adverse event of any grade, including two (8%) patients who experienced one or more events of grade 3 severity. No treatment-related deaths occurred. The overall response rate was 19% (95% confidence interval, 7%-39%). After a median follow-up of 12 months (range, 2-21 months), a median response duration was not reached (range, 6 to 17+ months); four of five responses lasted ≥6 months. Median overall survival was 11.6 months (95% confidence interval, 4.7-17.7 months). Pembrolizumab was well tolerated and had durable antitumor activity in patients with HNSCC from the Asia-Pacific region. (Trial registration no. NCT01848834.).

Atezolizumab versus chemotherapy in patients with platinum-treated locally advanced or metastatic urothelial carcinoma (IMvigor211): a multicentre, open-label, phase 3 randomised controlled trial

BACKGROUND

Few options exist for patients with locally advanced or metastatic urothelial carcinoma after progression with platinum-based chemotherapy. We aimed to assess the safety and efficacy of atezolizumab (anti-programmed death-ligand 1 [PD-L1]) versus chemotherapy in this patient population.

METHODS

We conducted this multicentre, open-label, phase 3 randomised controlled trial (IMvigor211) at 217 academic medical centres and community oncology practices mainly in Europe, North America, and the Asia-Pacific region. Patients (aged ≥18 years) with metastatic urothelial carcinoma who had progressed after platinum-based chemotherapy were randomly assigned (1:1), via an interactive voice and web response system with a permuted block design (block size of four), to receive atezolizumab 1200 mg or chemotherapy (physician's choice: vinflunine 320 mg/m², paclitaxel 175 mg/m², or 75 mg/m² docetaxel) intravenously every 3 weeks. Randomisation was stratified by PD-L1 expression (expression on <1% [IC0] or 1% to <5% [IC1] of tumour-infiltrating immune cells vs ≥5% of tumour-infiltrating immune cells [IC2/3]), chemotherapy type (vinflunine vs taxanes), liver metastases (yes vs no), and number of prognostic factors (none vs one, two, or three). Patients and investigators were aware of group allocation. Patients, investigators, and the sponsor were masked to PD-L1 expression status. The primary endpoint of overall survival was tested hierarchically in prespecified populations: IC2/3, followed by IC1/2/3, followed by the intention-to-treat population. This study, which is ongoing but not recruiting participants, is registered with ClinicalTrials.gov, number NCT02302807.

FINDINGS

Between Jan 13, 2015, and Feb 15, 2016, we randomly assigned 931 patients from 198 sites to receive atezolizumab (n=467) or chemotherapy (n=464). In the IC2/3 population (n=234), overall survival did not differ significantly between patients in the atezolizumab group and those in the chemotherapy group (median 11·1 months [95% CI 8·6-15·5; n=116] vs 10·6 months [8·4-12·2; n=118]; stratified hazard ratio [HR] 0·87, 95% CI 0·63-1·21; p=0·41), thus precluding further formal statistical analysis. Confirmed objective response rates were similar between treatment groups in the IC2/3 population: 26 (23%) of 113 evaluable patients had an objective response in the atezolizumab group compared with 25 (22%) of 116 patients in the chemotherapy group. Duration of response was numerically longer in the atezolizumab group than in the chemotherapy group (median 15·9 months [95% CI 10·4 to not estimable] vs 8·3 months [5·6-13·2]; HR 0·57, 95% CI 0·26-1·26). In the intention-to-treat population, patients receiving atezolizumab had fewer grade 3-4 treatment-related adverse events than did those receiving chemotherapy (91 [20%] of 459 vs 189 [43%] of 443 patients), and fewer adverse events leading to treatment discontinuation (34 [7%] vs 78 [18%] patients).

INTERPRETATION

Atezolizumab was not associated with significantly longer overall survival than chemotherapy in patients with platinum-refractory metastatic urothelial carcinoma overexpressing PD-L1 (IC2/3). However, the safety profile for atezolizumab was favourable compared with chemotherapy, Exploratory analysis of the intention-to-treat population showed well-tolerated, durable responses in line with previous phase 2 data for atezolizumab in this setting.

FUNDING

F Hoffmann-La Roche, Genentech.

Atezolizumab for the treatment of colorectal cancer: the latest evidence and clinical potential

INTRODUCTION

Atezolizumab is a fully humanized, engineered monoclonal antibody that specifically targets PD-L1, key molecule in the cancer-immunity pathway. Atezolizumab is currently approved for the treatment of metastatic non-small-cell lung cancer and advanced urothelial carcinomas. Areas covered: In this review, we will present the available data supporting the efficacy of atezolizumab for the treatment of metastatic colorectal cancer (mCRC). We will also provide an update on the ongoing/future clinical trials evaluating the role of atezolizumab for the treatment of CRC in different settings (alone or in combination with other checkpoint inhibitors and/or targeted therapies). So far, a small subgroup of mCRC (those with deficiency in mismatch repair - dMMR) appears to benefit significantly from checkpoint inhibitors. As expected, further research is needed to develop biomarkers, effective therapeutic strategies and novel combinations to overcome immune escape resistance and achieve better responses with minimal toxicities. Expert opinion: Interim analyses from ongoing early-phase studies in mCRC have shown encouraging activity of atezolizumab in combination with chemotherapy and/or targeted therapies, especially with MEK inhibitor cobimetinib. Within the next few years, this PD-L1 checkpoint inhibitor will likely be included as one of the treatment options for CRC, at least for patients with dMMR.

Atezolizumab in Platinum-treated Locally Advanced or Metastatic Urothelial Carcinoma: Clinical Experience from an Expanded Access Study in the United States

BACKGROUND

Atezolizumab (anti-programmed death-ligand 1) was approved in the USA, Europe, and elsewhere for treatment-naive and platinum-treated locally advanced/metastatic urothelial carcinoma (mUC).

OBJECTIVE

To report efficacy and safety from an atezolizumab expanded access study.

DESIGN, SETTING, AND PARTICIPANTS

This single-arm, open-label study enrolled 218 patients at 36 US sites. Key eligibility criteria included progression during/following ≥1 platinum-based chemotherapy for mUC or in perioperative setting (progression within 12 mo) and Eastern Cooperative Oncology Group performance status (ECOG PS) 0-2.

INTERVENTION

Patients received atezolizumab1200mg intravenously every 3 wk until loss of clinical benefit, unacceptable toxicity, consent withdrawal, decision to discontinue, death, atezolizumab commercial availability, or study closure.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Key end points reported herein included Response Evaluation Criteria in Solid Tumors v1.1 objective response rate and duration, disease control rate (DCR; response or stable disease), and safety.

RESULTS AND LIMITATIONS

All patients received prior systemic therapy (68% mUC; 27% adjuvant; and 26% neoadjuvant). At baseline, 57% of 214 treated patients had ECOG PS ≥1, 19% had hemoglobin <10g/dl, and 25% had liver metastases. Median treatment duration was 9 wk (interquartile range [IQR], 6-12 wk). Median follow-up duration was 2.3 mo (IQR, 1.6-3.4 mo) overall and 2.7 mo (IQR, 2.0-3.5 mo) in patients not known to have died. Seventeen of 114 evaluable patients (15%) had objective responses (16 ongoing at study termination). DCR was 49%. Treatment-related adverse events (mostly fatigue) occurred in 98 of 214 treated patients.

CONCLUSIONS

The benefit/risk profile of atezolizumab was consistent with that observed in previous studies, despite pretreatment and poor prognostic factors. These results suggest a potential role for atezolizumab in a broader patient range than typically eligible for phase 1-3 studies.

PATIENT SUMMARY

In this expanded access study, atezolizumab was active and tolerable in a range of patients with platinum-treated metastatic urothelial carcinoma.

Therapeutic strategies for organ-confined and non-organ-confined bladder cancer after radical cystectomy

INTRODUCTION

In patients with muscle invasive or Bacillus Calmette-Guérin refractory urothelial carcinoma of the urinary bladder (UCUB) radical cystectomy represents the standard of care. However, a proportion of patients experience disease progression, local recurrence and/or metastatic disease. Areas covered: This review provides an overview of available therapeutic strategies after radical cystectomy and examines ongoing clinical trials including cytotoxic chemotherapy and immunotherapy. Expert commentary: Cytotoxic chemotherapy offers limited benefit in UCUB patients. However, the recent introduction of immunotherapy provides new hope for durable responses or possibly complete cures.

Recent developments in the treatment of advanced bladder cancer

Urothelial carcinoma of the bladder is a common malignancy which has historically been difficult to treat in its advanced stages. Clinically effective treatment options for locally advanced/inoperable or metastatic urothelial carcinoma (mUC) consisted of cisplatin-based chemotherapy regimens, with few other impactful therapeutic options. The past 2 years have seen a remarkable shift in the therapeutic landscape of mUC, with 5 novel immunotherapy agents receiving FDA approval for mUC, including first-line and second-line postplatinum settings. There are now many important clinical trials ongoing seeking to answer how best to use chemotherapy, immunotherapy, and targeted therapy agents in patients with mUC. Here we review the current standard of care for patients with mUC based on published data from the past 2 years, and look forward toward future research directions.

Surrogate end points for overall survival in trials of PD-(L)1 inhibitors for urinary cancers: a systematic review

Aim: Numerous trials for PD-(L)1 inhibitors in the management of advanced urinary cancers (urothelial carcinoma and renal cell carcinoma) were published recently. It is not known exactly what should be the optimal surrogate end point for overall survival (OS) in this context. Materials & methods: PubMed database and ASCO meeting library were searched till August 2017. Eligible studies included prospective clinical studies evaluating PD-(L)1 inhibitors for the management of advanced urothelial carcinoma or renal cell carcinoma. The review author extracted relevant data on the characteristics of participants and the outcomes of the different studies. In order to conduct a proper correlation analysis, normality testing using Shapiro-Wilk test was first used. Based on the result of the normality testing, either Pearson's product–moment correlation or Spearman's rank correlation was used. Results: Thirteen trials (nine urothelial carcinoma and four renal cell carcinoma trials) with 2792 participants were included. The correlation of overall response rate with median OS was very weak to weak (for urothelial carcinoma: r = -0.120, n = 9, p = 0.758; for renal cell carcinoma: r = -0.397, n = 6, p = 0.436). Likewise, the correlation of progression-free survival with median OS was very weak to weak (for urothelial carcinoma: r = -0.024, n = 8, p = 0.955; for renal cell carcinoma: r = 0.394, n = 6, p = 0.440). On the other hand, 1-year survival rate may be a better surrogate end point for median OS (for urothelial carcinoma: r = 0.806, n = 8, p = 0.016; for renal cell carcinoma: r = 0.941, n = 6, p = 0.005). Conclusion: RECIST-defined overall response rate and progression-free survival are not reliable surrogate end points for median OS in trials of PD-(L)1 inhibitor therapy for urinary cancers. The use of other surrogate end points (e.g., 1-year survival) in early phase studies may be considered.

Immune checkpoint inhibitors for metastatic bladder cancer

Chemotherapy has represented the standard therapy for unresectable or metastatic urothelial carcinoma for more than 20 years. The growing knowledge of the interaction between tumour and immune system has led to the advent of new classes of drugs, the immune-checkpoints inhibitors, which are intended to change the current scenario. To date, immunotherapy is able to improve the overall responses and survival. Moreover, thanks to its safety profile immune-checkpoint inhibitors could be proposed also to patients unfit for standard chemotherapy. No doubts that these agents have started a revolution expected for years, but despite this encouraging results it appears clear that not all subjects respond to these agents and requiring the development of reliable predictive response factors able to isolate patients who can more benefit from these treatments as well as new strategies aimed to improve immunotherapy clinical outcome. In this review we describe the active or ongoing clinical trials involving Programmed Death Ligand 1 (PD-L1), Programmed Death receptor 1 (PD-1) and Cytotoxic-T Lymphocyte Antigen 4 (CTLA 4) inhibitors in urothelial carcinoma focusing our attention on the developing new immune-agents and combination strategies with immune-checkpoint inhibitors.

Blockade of Tumor-Expressed PD-1 promotes lung cancer growth

Anti-PD-1 immunotherapy is the standard of care for treating many patients with non-small cell lung cancer (NSCLC), yet mechanisms of treatment failure are emerging. We present a case of NSCLC, who rapidly progressed during a trial (NCT02318771) combining palliative radiotherapy and pembrolizumab. Planned tumor biopsy demonstrated PD-1 expression by NSCLC cells. We validated this observation by detecting PD-1 transcript in lung cancer cells and by co-localizing PD-1 and lung cancer-specific markers in resected lung cancer tissues. We further investigated the biological role of cancer-intrinsic PD-1 in a mouse lung cancer cell line, M109. Knockout or antibody blockade of PD-1 enhanced M109 viability in-vitro, while PD-1 overexpression and exposure to recombinant PD-L1 diminished viability. PD-1 blockade accelerated growth of M109-xenograft tumors with increased proliferation and decreased apoptosis in immune-deficient mice. This represents a first-time report of NSCLC-intrinsic PD-1 expression and a potential mechanism by which PD-1 blockade may promote cancer growth.

Tackling Cancer Resistance by Immunotherapy: Updated Clinical Impact and Safety of PD-1/PD-L1 Inhibitors

Cancer therapy has been constantly evolving with the hope of finding the most effective agents with the least toxic effects to eradicate tumors. Cancer immunotherapy is currently among the most promising options, fulfilling this hope in a wide range of tumors. Immunotherapy aims to activate immunity to fight cancer in a very specific and targeted manner; however, some abnormal immune reactions known as immune-related adverse events (IRAEs) might occur. Therefore, many researchers are aiming to define the most proper protocols for managing these complications without interfering with the anticancer effect. One of these targeted approaches is the inhibition of the interaction between the checkpoint protein, programmed death-receptor 1 (PD-1), and its ligand, programmed death-ligand 1 (PD-L1), via a class of antibodies known as PD-1/PD-L1 inhibitors. These antibodies achieved prodigious success in a wide range of malignancies, including those where optimal treatment is not yet fully identified. In this review, we have critically explored and discussed the outcome of the latest PD-1 and PD-L1 inhibitor studies in different malignancies compared to standard chemotherapeutic alternatives with a special focus on the clinical efficacy and safety. The approval of the clinical applications of nivolumab, pembrolizumab, atezolizumab, avelumab, and durvalumab in the last few years clearly highlights the hopeful future of PD-1/PD-L1 inhibitors for cancer patients. These promising results of PD-1/PD-L1 inhibitors have encouraged many ongoing preclinical and clinical trials to explore the extent of antitumor activity, clinical efficacy and safety as well as to extend their applications.

Role of immunotherapy in bladder cancer: past, present and future

As research focus in oncology has recently shifted from oral targeted therapy to immunomodulation, the era of successful drug development in bladder cancer has just begun. This has led to unprecedented approval of five immunotherapeutic agents by regulatory agencies for metastatic bladder cancer within a span of 12 months. With an initial triumph of anti-programmed cell death-1 (anti-PD-1) and anti-programmed cell death ligand-1 (anti-PDL-1) drugs, ongoing efforts are aimed at identification and validation of new druggable immune targets to consolidate the initial gains. In this paper, we review the role of immunotherapy in the treatment of bladder cancer as well as the various emerging immunotherapeutic agents and their possible use in bladder cancer.

Effectiveness of anti-PD-1/PD-L1 antibodies in urothelial carcinoma patients with different PD-L1 expression levels: a meta-analysis

Background

Urothelial carcinoma ranks the ninth among malignant cancers. We conducted this study to identify which patients could benefit more from the treatment of programmed death-1 (PD–1)/programmed death-ligand1 (PD–L1) inhibitors.

Materials and Methods

We performed literature searches, combined data from qualified literature and performed comparative analyses on the effectiveness of anti-PD–1/PD–L1 antibodies in patients with different PD–L1 expression levels.

Results

We divided patients into three groups according to the percentages of PD–L1-positive cells, namely the low- PD-L1 (PD-L1 < 1%), the medium-PD-L1 (PD-L1 ≥ 1 and < 5%) and the high–PD–L1 (PD-L1 ≥ 5%) groups. We found that the high-PD-L1 group responded significantly better than other groups (P = 0.0003, ORs = 0.45, 95%CI: 0.29-071; P = 0.0009, ORs = 0.43, 95%CI: 0.25-0.73, for low-PD-L1 and medium-PD-L1 groups, respectively), while the latter two groups responded similarly (P = 0.90, ORs = 1.06, 95%CI: 0.62-1.83) to both PD–1 and PD–L1 inhibitors. Furthermore, we found that the medium-PD–L1 and high-PD–L1 groups responded similarly to PD-1/ PD-L1 inhibitors (P = 0.65, ORs = 1.11, 95%CI: 0.69–1.77), while the low-PD–L1 group responded better to PD-1 inhibitors than PD-L1 inhibitors (P = 0.046, ORs = 1.92, 95%CI: 0.98–3.89).

Conclusions

Our results suggest that PD–L1 positive patients should be defined as those with ≥ 5% or greaterPD-L1-positive cells. PD-1 antibodies performed better only in the low-group patients, likely because they could block the interactions of PD–1 with both PD–L1 and PD–L2.

New therapies in nonmuscle invasive bladder cancer treatment

Introduction:

Nonmuscle invasive bladder cancer (NMIBC) remains a very challenging disease to treat with high rates of recurrence and progression associated with current therapies. Recent technological and biological advances have led to the development of novel agents in NMIBC therapy.

Methods:

We reviewed existing literature as well as currently active and recently completed clinical trials in NMIBC by querying PubMed.gov and clinicaltrials.gov.

Results:

A wide variety of new therapies in NMIBC treatment are currently being developed, utilizing recent developments in the understanding of immune therapies and cancer biology.

Conclusion:

The ongoing efforts to develop new therapeutic approaches for NMIBC look very promising and are continuing to evolve.

Investigational PD-1 inhibitors in HL and NHL and biomarkers for predictors of response and outcome

INTRODUCTION

Inhibitors against the PD-1/PD-L1 pathway are revolutionizing the treatment and management of malignancies.

AREAS COVERED

We summarize our current understanding of the function of PD-1, its role in immune evasion, the clinical data available that support the use of PD-1 antagonist in Hodgkin and non-Hodgkin lymphomas, and potential predictors of response.

EXPERT OPINION

We anticipate that in the next 10 years, agents that modulate the immune system such as PD-1 antagonists will be increasingly used in favor over traditional cytotoxic chemotherapeutic agents. PD-1 antagonists will be combined with future immunotherapies or used as adjuncts to cellular therapy to boost tumor-specific immune responses.

Current Role of Checkpoint Inhibitors in Urologic Cancers

Harnessing the host immune system to combat genitourinary cancers has key theoretical advantages over other anticancer strategies including specificity and memory which should translate to favorable tolerability and response durability in the clinic. Indeed, key examples of the potential for immunotherapeutic treatment of solid tumors are derived from data in genitourinary cancers including Bacillus Calmette-Guerin for urothelial cancer, sipuleucel-T for prostate cancer, and interleukin-2 for renal cancer. Despite these successes, developing effective immunotherapeutic strategies for the treatment of cancer has largely been hampered by an incomplete understanding of tumor immunobiology and mechanisms of immune resistance. In just a few years since entering the clinic, immune checkpoint blockade has dramatically changed the landscaped of treatment for genitourinary cancer and has secured a place as a standard pillar of treatment. Further iterative bench-bedside-bench research is anticipated to extend the benefits of immunotherapeutic-based approaches to additional patients.

Pembrolizumab for the treatment of bladder cancer

INTRODUCTION

Until recently, patients with locally advanced or metastatic urothelial carcinoma after progression on cisplatin-containing chemotherapy had limited systemic treatment options with no significant survival benefit and poor tolerability. Advances in the field of immunotherapy with the introduction of checkpoint inhibitors have led to paradigm shifts in the treatment of various malignancies. Areas covered: The current review will summarize the clinical evidence of checkpoint inhibitors in bladder cancer, with a focus on pembrolizumab. Expert commentary: Category 1 evidence indicates that the checkpoint inhibitor pembrolizumab improves overall survival in patients with locally advanced or metastatic urothelial carcinoma who progressed after or during cisplatin-containing therapy as compared to current standard of care chemotherapy. Phase 1 and 2 evidence also indicates that checkpoint inhibitors are active in first line in patients who are ineligible for cisplatin-containing chemotherapy.

Avelumab in metastatic urothelial carcinoma after platinum failure (JAVELIN Solid Tumor): pooled results from two expansion cohorts of an open-label, phase 1 trial

BACKGROUND

The approval of anti-programmed death ligand 1 (PD-L1) and anti-programmed death 1 agents has expanded treatment options for patients with locally advanced or metastatic urothelial carcinoma. Avelumab, a human monoclonal anti-PD-L1 antibody, has shown promising antitumour activity and safety in this disease. We aimed to assess the safety profile in patients (both post-platinum therapy and cisplatin-naive) treated with avelumab and to assess antitumour activity of this drug in post-platinum patients.

METHODS

In this pooled analysis of two cohorts from the phase 1 dose-expansion JAVELIN Solid Tumor study, patients aged 18 years and older with histologically or cytologically confirmed locally advanced or metastatic urothelial carcinoma that had progressed after at least one previous platinum-based chemotherapy were enrolled from 80 cancer treatment centres or hospitals in the USA, Europe, and Asia. Eligible patients had adequate end-organ function, an Eastern Cooperative Oncology Group performance status of 0 or 1, life expectancy of at least 3 months, and at least one measurable lesion. Cisplatin-ineligible patients who might have been previously treated in the perioperative setting, including platinum-naive patients, were also eligible. Patients unselected for PD-L1 expression received avelumab (10 mg/kg, 1 h intravenous infusion) every 2 weeks until confirmed disease progression, unacceptable toxicity, or other criterion for withdrawal. The primary endpoint for this efficacy expansion cohort was confirmed best overall response (according to RECIST version 1.1), adjudicated by independent review. Safety analysis was done in all patients who received at least one dose of avelumab. Antitumour activity was assessed in post-platinum patients who received at least one dose of avelumab. This trial is registered with ClinicalTrials.gov, number NCT01772004; enrolment in this cohort of patients with metastatic urothelial carcinoma is closed and the trial is ongoing.

FINDINGS

Between Sept 3, 2014, and March 15, 2016, 329 patients with advanced metastatic urothelial carcinoma were screened for enrolment into this study; 249 patients were eligible and received treatment with avelumab for a median of 12 weeks (IQR 6·0-19·7) and followed up for a median of 9·9 months (4·3-12·1). Safety and antitumour activity were evaluated at data cutoff on June 9, 2016. In 161 post-platinum patients with at least 6 months of follow-up, a best overall response of complete or partial response was recorded in 27 patients (17%; 95% CI 11-24), including nine (6%) complete responses and 18 (11%) partial responses. The most frequent treatment-related adverse events (any grade in ≥10% patients) were infusion-related reaction (73 [29%]; all grade 1-2) and fatigue (40 [16%]). Grade 3 or worse treatment-related adverse events occurred in 21 (8%) of 249 patients, the most common of which were fatigue (four [2%]), and asthenia, elevated lipase, hypophosphataemia, and pneumonitis in two (1%) patients each. 19 (8%) of 249 patients had a serious adverse event related to treatment with avelumab, and one treatment-related death occurred (pneumonitis).

INTERPRETATION

Avelumab showed antitumour activity in the treatment of patients with platinum-refractory metastatic urothelial carcinoma; a manageable safety profile was reported in all avelumab-treated patients. These data provide the rationale for therapeutic use of avelumab in metastatic urothelial carcinoma and it has received accelerated US FDA approval in this setting on this basis.

FUNDING

Merck KGaA, and Pfizer Inc.

Do we have biomarkers to predict response to neoadjuvant and adjuvant chemotherapy and immunotherapy in bladder cancer?

Radical cystectomy (RC) is the standard of care treatment of localized muscle-invasive bladder cancer (BC). However, about 50% of patients develop metastases within 2 years after cystectomy. Neoadjuvant cisplatin-based chemotherapy before cystectomy improves the overall survival (OS) in patients with muscle-invasive BC. Pathological response to neoadjuvant treatment is a strong predictor of better disease-specific survival. Nevertheless, some patients do not benefit from chemotherapy. The identification of reliable biomarkers enabling clinicians to identify patients who might benefit from chemotherapy is a very important clinical task. An identification tool could lead to individualized therapy, optimizing response rates. In addition, unnecessary treatment with chemotherapy which potentially leads to a loss of quality of life and which might also might cause a delay of cystectomy in a neoadjuvant setting could be avoided. The present review aims to summarize and discuss the current literature on biomarkers for the prediction of response to systemic therapy in muscle-invasive BC. Tremendous efforts in genetic and molecular characterization have led to the identification of predictive candidate biomarkers in urothelial carcinoma (UC), although prospective validation is pending. Ongoing clinical trials examining the benefit of individual therapies in UC of the bladder (UCB) by molecular patient selection hold promise to shed light on this question.

Pembrolizumab in the treatment of advanced urothelial cancer

Pembrolizumab is a humanized monoclonal antibody that targets PD-1. In the Phase III trial KEYNOTE-045, pembrolizumab was associated with a significant overall survival benefit when compared with docetaxel, paclitaxel and vinflunine in second line metastatic urothelial carcinoma (UC). Additionally, in the first line, early results from an interim analysis of the Phase II trial Keynote-052 study indicated that pembrolizumab is efficacious for cisplatin-ineligible patients. Based on data from these trials, pembrolizumab was the most recent among the five checkpoint inhibitors tested in UC to be approved by the US FDA in May 2017. It was granted regular approval for patients with advanced-stage UC who progress after receiving platinum-based chemotherapy and accelerated approval in the first line for patients who are ineligible to receive cisplatin.

Assessing Tumor-Infiltrating Lymphocytes in Solid Tumors: A Practical Review for Pathologists and Proposal for a Standardized Method from the International Immuno-Oncology Biomarkers Working Group: Part 2: TILs in Melanoma, Gastrointestinal Tract Carcinomas, Non-Small Cell Lung Carcinoma and Mesothelioma, Endometrial and Ovarian Carcinomas, Squamous Cell Carcinoma of the Head and Neck, Genitourinary Carcinomas, and Primary Brain Tumors

Assessment of the immune response to tumors is growing in importance as the prognostic implications of this response are increasingly recognized, and as immunotherapies are evaluated and implemented in different tumor types. However, many different approaches can be used to assess and describe the immune response, which limits efforts at implementation as a routine clinical biomarker. In part 1 of this review, we have proposed a standardized methodology to assess tumor-infiltrating lymphocytes (TILs) in solid tumors, based on the International Immuno-Oncology Biomarkers Working Group guidelines for invasive breast carcinoma. In part 2 of this review, we discuss the available evidence for the prognostic and predictive value of TILs in common solid tumors, including carcinomas of the lung, gastrointestinal tract, genitourinary system, gynecologic system, and head and neck, as well as primary brain tumors, mesothelioma and melanoma. The particularities and different emphases in TIL assessment in different tumor types are discussed. The standardized methodology we propose can be adapted to different tumor types and may be used as a standard against which other approaches can be compared. Standardization of TIL assessment will help clinicians, researchers and pathologists to conclusively evaluate the utility of this simple biomarker in the current era of immunotherapy.

Potential role of radiation therapy in augmenting the activity of immunotherapy for gynecologic cancers

Immune checkpoint inhibitors have become an area of intense interest in oncology and are actively being studied in a variety of cancer types with a wide range of success. In vitro data suggest mechanisms by which radiation can activate the immune system, and ongoing studies are exploring the potential interaction of checkpoint inhibitors with radiotherapy in both preclinical and clinical settings. Gynecologic malignancies are a heterogeneous group of tumors with varying prognoses, intrinsic immunogenicity, and potential for response to immune-based therapies. In this review, we focus on the rationale for immunotherapy and opportunities for augmentation by photon radiotherapy in cancers of the cervix, endometrium, and ovary.