Endocytosis Inhibition in Humans to Improve Responses to ADCC-Mediating Antibodies.

A safe and controlled manipulation of endocytosis in vivo may have disruptive therapeutic potential. Here, we demonstrate that the anti-emetic/anti-psychotic prochlorperazine can be repurposed to reversibly inhibit the in vivo endocytosis of membrane proteins targeted by therapeutic monoclonal antibodies, as directly demonstrated by our human tumor ex vivo assay. Temporary endocytosis inhibition results in enhanced target availability and improved efficiency of natural killer cell-mediated antibody-dependent cellular cytotoxicity (ADCC), a mediator of clinical responses induced by IgG1 antibodies, demonstrated here for cetuximab, trastuzumab, and avelumab. Extensive analysis of downstream signaling pathways ruled out on-target toxicities. By overcoming the heterogeneity of drug target availability that frequently characterizes poorly responsive or resistant tumors, clinical application of reversible endocytosis inhibition may considerably improve the clinical benefit of ADCC-mediating therapeutic antibodies.

Reshaping the tumor microenvironment of cold soft-tissue sarcomas with oncolytic viral therapy: a phase 2 trial of intratumoral JX-594 combined with avelumab and low-dose cyclophosphamide.

Most soft-tissue sarcomas (STS) exhibit an immunosuppressive tumor microenvironment (TME), leading to resistance against immune checkpoint inhibitors (ICIs) and limited therapeutic response. Preclinical data suggest that oncolytic viral therapy can remodel the TME, facilitating T cell accumulation and enhancing the immunogenicity of these tumors.We conducted the METROMAJX, a phase II clinical trial, to investigate the combination of JX-594, an oncolytic vaccinia virus engineered for selective tumor cell replication, with metronomic cyclophosphamide and the PD-L1 inhibitor avelumab in patients with advanced, 'cold' STS, characterized by an absence of tertiary lymphoid structures. The trial employed a two-stage Simon design. JX-594 was administered intratumorally at a dose of 1.109 pfu every 2 weeks for up to 4 intra-tumoral administrations. Cyclophosphamide was given orally at 50 mg twice daily in a week-on, week-off schedule, and avelumab was administered at 10 mg/kg biweekly. The primary endpoint was the 6-month non-progression rate.Fifteen patients were enrolled, with the most frequent toxicities being grade 1 fatigue and fever. Fourteen patients were assessable for efficacy analysis. At 6 months, only one patient remained progression-free, indicating that the trial did not meet the first stage endpoint of Simon's design. Analysis of sequential tissue biopsies and plasma samples revealed an increase in CD8 density and upregulation of immune-related protein biomarkers, including CXCL10.Intra-tumoral administration of JX-594 in combination with cyclophosphamide and avelumab is safe and capable of modulating the TME in cold STS. However, the limited efficacy observed warrants further research to define the therapeutic potential of oncolytic viruses, particularly in relation to specific histological subtypes of STS.

Avelumab treatment for patients with metastatic Merkel cell carcinoma can be safely stopped after 1 year and a PET/CT-confirmed complete response.

BACKGROUND: Immune checkpoint inhibitor treatment of patients with metastatic Merkel cell carcinoma (mMCC) has shown high response rates, ranging from 33% to 73%. The ideal duration of treatment, however, is currently unknown. The aim of this study was to evaluate if avelumab treatment for mMCC can be safely stopped after 1 year of treatment and a complete response (CR) confirmed by fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) imaging. METHODS: Patients who received more than one dose of avelumab treatment for mMCC between November 2017 and February 2022 were included in this study. Treatment was discontinued in case of a FDG-PET/CT confirmed CR after 1 year (26 cycles) of avelumab or a CR and unacceptable toxicity earlier. The primary end point was recurrence-free survival (RFS). RESULTS: Sixty-five patients were included: 25 (38%) had a FDG-PET/CT-confirmed CR at discontinuation of avelumab. In those 25 patients, reasons for discontinuation of treatment were completion of 1 year of treatment in 13 (52%), toxicity in five (20%), and patient preference in seven (28%). Median duration of treatment in this group was 11 months (interquartile range, 6.1-11.7). Median follow-up was 27 months (interquartile range, 15.8-33.8). The 12-month RFS was 88% (95% CI, 0.74-1) and median RFS was not reached. Two patients (8%) had a recurrence at 4 and 7 months after discontinuation of treatment. CONCLUSIONS: Patients with mMCC who acquire a CR on PET/CT imaging appear to have durable responses after discontinuation of treatment after 1 year.

MITO END-3: efficacy of avelumab immunotherapy according to molecular profiling in first-line endometrial cancer therapy.

BACKGROUND: Immunotherapy combined with chemotherapy significantly improves progression-free survival (PFS) compared to first-line chemotherapy alone in advanced endometrial cancer (EC), with a much larger effect size in microsatellite instability-high (MSI-H) cases. New biomarkers might help to select patients who may have benefit among those with a microsatellite-stable (MSS) tumor. PATIENTS AND METHODS: In a pre-planned translational analysis of the MITO END-3 trial, we assessed the significance of genomic abnormalities in patients randomized to standard carboplatin/paclitaxel without or with avelumab. RESULTS: Out of 125 randomized patients, 109 had samples eligible for next-generation sequencing analysis, and 102 had MSI tested. According to The Cancer Genome Atlas (TCGA), there were 29 cases with MSI-H, 26 with MSS TP53 wild type (wt), 47 with MSS TP53 mutated (mut), and 1 case with POLE mutation. Four mutated genes were present in >30% of cases: TP53, PIK3CA, ARID1A, and PTEN. Eleven patients (10%) had a BRCA1/2 mutation (five in MSI-H and six in MSS). High tumor mutational burden (≥10 muts/Mb) was observed in all MSI-H patients, in 4 out of 47 MSS/TP53 mut, and no case in the MSS/TP53 wt category. The effect of avelumab on PFS significantly varied according to TCGA categories, being favorable in MSI-H and worst in MSS/TP53 mut (P interaction = 0.003); a similar non-significant trend was seen in survival analysis. ARID1A and PTEN also showed a statistically significant interaction with treatment effect, which was better in the presence of the mutation (ARID1A P interaction = 0.01; PTEN P interaction = 0.002). CONCLUSION: The MITO END-3 trial results suggest that TP53 mutation is associated with a poor effect of avelumab, while mutations of PTEN and ARID1A are related to a positive effect of the drug in patients with advanced EC.

Immune Checkpoint Inhibitor Therapy for Periocular Merkel Cell Carcinoma.

We herein report four patients with periocular Merkel cell carcinoma treated with immune checkpoint inhibitors who experienced a dramatic response and, therefore, had less morbid surgery and/or avoided radiation therapy with its inherent ocular toxicity.

Experience and Prognostic Analysis with Avelumab Switch Maintenance Treatment in Metastatic Urothelial Carcinoma.

INTRODUCTION: Avelumab (Ave) is approved for metastatic urothelial carcinoma (mUC) maintenance therapy and prolongs overall survival (OS). We explored trends related to Ave treatment of mUC patients. METHODS: A total of 72 patients with mUC treated with first-line chemotherapy, from January 2019 to November 2022, at our affiliated institutions, were analyzed. We compared clinical parameters and the prognosis of patients treated with Ave (n = 43) because of progression during first-line chemotherapy, with untreated patients (Ave-untreated; n = 29). Among the Ave-treated group, we classified patients showing a complete or partial response or stable disease in their best response to Ave maintenance therapy as Ave-suitable patients; these were retrospectively analyzed. Potential prognostic factors, including the Geriatric Nutritional Risk Index (GNRI) for determining patients suitable for Ave, were evaluated. RESULTS: The basic clinical parameters of patients when first-line treatment was initiated were not statistically different between the two groups. The Ave-suitable group (median 26.6 months, 95% confidence interval [CI]: 19.4-not reached [NR]) showed significantly longer median OS after first-line treatment than the Ave-untreated group (median 12.0 months, 95% CI: 7.5-NR) with tolerable adverse events. The cut-off values of prognostic factors were set by the receiver operating characteristic curve. Low age and GNRI sustainability were revealed as significant prognostic factors for being Ave-suitable both in univariate and multivariate analysis. CONCLUSION: In mUC, Ave maintenance prolonged OS within tolerable safety profiles. GNRI sustainability may be used as a biomarker to predict being Ave-suitable.

Combination immune checkpoint and targeted protein kinase inhibitors for the treatment of renal cell carcinomas.

Kidney cancers comprise about 3% of all new malignancies in the United States. Renal cell carcinomas (RCCs) are the most common type of renal malignancy making up about 85% of kidney cancer cases. Signs and symptoms of renal cell carcinomas can result from local tumor growth, paraneoplastic syndromes, or distant metastases. The classic triad of presentation with flank pain, hematuria, and a palpable abdominal mass occurs in fewer than 10% of patients. Most diagnoses result from incidental imaging findings (ultrasonography or abdominal CT imaging) performed for another reason. Localized disease is treated by partial nephrectomy, total nephrectomy, or ablation (tumor destruction with heat or cold). When the tumors have metastasized, systemic therapy with protein-tyrosine kinase antagonists including sorafenib, sunitinib, pazopanib, and tivozanib that target vascular endothelial, platelet-derived, fibroblast, hepatocyte, and stem cell factor growth factor receptors (VEGFR, PDGFR, FGFR, MET, and Kit) were prescribed after 2005. The monoclonal antibody immune checkpoint inhibitor nivolumab (targeting programed cell death protein 1, PD1) was approved for the treatment of RCCs in 2015. It is usually used now in combination with ipilimumab (targeting CTLA-4) or cabozantinib (a multikinase blocker). Other combination therapies include pembrolizumab (targeting PD1) and axitinib (a VEGFR and PDGFR blocker) or lenvatinib (a multikinase inhibitor). Since the KEYNOTE-426 clinical trial, the use of immune checkpoint inhibitors in combination with protein-tyrosine kinase inhibitors is now the standard of care for most patients with metastatic renal cell carcinomas and monotherapies are used only in those individuals who cannot receive or tolerate immune checkpoint inhibitors.

Cost-effectiveness analysis for avelumab first-line maintenance treatment of advanced urothelial carcinoma in Scotland.

Aim: The cost-effectiveness of avelumab first-line maintenance treatment for locally advanced or metastatic urothelial carcinoma in Scotland was assessed. Materials & methods: A partitioned survival model was developed comparing avelumab plus best supportive care (BSC) versus BSC alone, incorporating JAVELIN Bladder 100 trial data, costs from national databases and published literature and clinical expert validation of assumptions. Incremental cost-effectiveness ratio (ICER) was estimated using lifetime costs and quality-adjusted life-years (QALY). Results: Avelumab plus BSC had incremental costs of £9446 and a QALY gain of 0.63, leading to a base-case (deterministic) ICER of £15,046 per QALY gained, supported by robust sensitivity analyses. Conclusion: Avelumab first-line maintenance is likely to be a cost-effective treatment for locally advanced or metastatic urothelial carcinoma in Scotland.

What is this article about? This study looked at the costs of avelumab when given as maintenance treatment for people in Scotland with advanced urothelial carcinoma, compared with the longer survival and other benefits that it provides. How was this done? Researchers estimated the costs and treatment benefits expected with avelumab using data from a clinical trial called JAVELIN Bladder 100, national databases, data from previously published studies and expert opinions. What were the results? Costs associated with using avelumab maintenance treatment for people with advanced urothelial carcinoma in Scotland were considered to be acceptable based on the benefits it provides. What do the results of the study mean? These results support the use of avelumab first-line maintenance as a standard treatment for people with advanced urothelial carcinoma in Scotland.

The JAVELIN Bladder Medley trial: avelumab-based combinations as first-line maintenance in advanced urothelial carcinoma.

Results from JAVELIN Bladder 100 established avelumab (anti-PD-L1) first-line maintenance as the standard-of-care treatment for patients with advanced urothelial carcinoma (UC) that has not progressed with first-line platinum-based chemotherapy. We describe the design of JAVELIN Bladder Medley (NCT05327530), an ongoing phase II, multicenter, randomized, open-label, parallel-arm, umbrella trial. Overall, 252 patients with advanced UC who are progression-free following first-line platinum-based chemotherapy will be randomized 1:2:2:2 to receive maintenance therapy with avelumab alone (control group) or combined with sacituzumab govitecan (anti-Trop-2/topoisomerase inhibitor conjugate), M6223 (anti-TIGIT) or NKTR-255 (recombinant human IL-15). Primary end points are progression-free survival per investigator and safety/tolerability of the combination regimens. Secondary end points include overall survival, objective response and duration of response per investigator, and pharmacokinetics.

Urothelial cancer develops in the urinary tract, which contains the parts of the body that move urine from the kidneys to outside of the body. Urothelial cancer is called advanced when it has spread outside of the urinary tract. Chemotherapy is often the first main treatment given to people with advanced urothelial cancer. Avelumab is an immunotherapy drug that can help the body's immune system find and destroy cancer cells. Results from a trial called JAVELIN Bladder 100 looked at avelumab maintenance treatment, which is given after chemotherapy. The trial showed that avelumab maintenance treatment helped people with advanced urothelial cancer live longer than people who were not treated with avelumab. Avelumab also helped people have a longer time without their cancer getting worse. Avelumab is the only approved maintenance treatment available for people with advanced urothelial cancer that has not worsened after chemotherapy. The JAVELIN Bladder Medley trial will assess whether avelumab maintenance treatment given in combination with other anticancer drugs can help people with advanced urothelial cancer live longer and have a longer time without their cancer getting worse compared with avelumab alone. Researchers will also look at the side effects people have when they receive avelumab alone or combined with the other anticancer drugs in this trial. Results will show whether the benefit of avelumab maintenance treatment can be improved by combining avelumab with other anticancer drugs. People started joining this trial in August 2022. Results will be reported in the future. Clinical Trial Registration: NCT05327530 (ClinicalTrials.gov).

Trend in overall survival from the start of first-line chemotherapy in patients with metastatic urothelial carcinoma.

New approaches involving immune checkpoint inhibitors and antibody-drug conjugates prolong overall survival in patients with metastatic urothelial carcinoma. However, the access to such systemic therapy in clinical practice is suboptimal, and whether these agents improve overall survival in patients with metastatic urothelial carcinoma over time remains unclear. Hence, we investigated the overall survival trend from the initiation of first-line therapy with these agents to identify changes due to the medication and time of treatment initiation. We retrospectively evaluated 195 patients from a single center. They were treated with chemotherapy, pembrolizumab, or avelumab or enfortumab vedotin. The treatment was categorized into chemotherapy, pembrolizumab or avelumab/enfortumab vedotin period. The new agents prolonged overall survival from the start of first-line therapy. Furthermore, sequential treatment with these agents in real-world clinical practice has been reported to prolong overall survival. These study results will have major implications when a new first-line therapy is approved in the future.

Enfortumab vedotin following platinum-based chemotherapy and immune checkpoint inhibitors for advanced urothelial carcinoma: response, survival and safety analysis from a multicentre real-world Japanese cohort.

OBJECTIVE: Real-world evidence regarding enfortumab vedotin for unresectable or metastatic urothelial carcinoma is scarce, particularly in Japan. We investigated real-world data focusing on patient background, previous treatments, response, survival and adverse events in patients receiving enfortumab vedotin. METHODS: A multicentre database was used to register 556 patients diagnosed with metastatic urothelial carcinoma from 2008 to 2023; 34 patients (6.1%) treated with enfortumab vedotin were included. Best radiographic objective responses were evaluated using the Response Evaluation Criteria in Solid Tumors (v1.1) during treatments. Overall survival and progression-free survival were estimated (Kaplan-Meier method). Toxicities were reported according to the Common Terminology Criteria for Adverse Events, version 5.0. The relative dose intensity, which could impact oncological outcomes, was calculated. RESULTS: The median number of enfortumab vedotin therapy cycles was 5. The best objective response to enfortumab vedotin was partial response, stable disease and progressive disease in 19 (56%), 5 (15%) and 10 (29%) patients, respectively. The median overall survival and progression-free survival after the first enfortumab vedotin dose were 16 and 9 months, respectively. No significant relationship was observed between survival outcomes after enfortumab vedotin initiation and the enfortumab vedotin relative dose intensity. The median overall survival from first-line platinum-based chemotherapy initiation was 42 months. Twenty-six (76%) patients experienced any grade of enfortumab vedotin-related toxicities; eight (24%) experienced Grades 3-4 toxicities, the most common being skin toxicity (any grade, 47%; Grades 3-4, 12%). CONCLUSIONS: Here, we report real-world evidence for enfortumab vedotin therapy in Japan. Tumour responses and safety profiles were comparable with those of clinical trials on this novel treatment.

Difference of oncological efficacy between two immune checkpoint inhibitors following first-line platinum-based chemotherapy in patients with unresectable, metastatic, advanced urothelial carcinoma: a multicenter real-world Japanese cohort.

BACKGROUND: Maintenance avelumab is currently recommended for patients with unresectable and/or metastatic (mUC) achieving at least stable disease (SD) on first-line platinum-based chemotherapy (1L-CT). Pembrolizumab is an alternative therapeutic avenue for this patient cohort in clinical practice. We investigated real-world data, focusing on the correlation between response to 1L-CT and oncological efficacy of subsequent immune checkpoint inhibitor (ICI) therapy with avelumab or pembrolizumab. METHODS: A multicenter database registered 626 patients with mUC diagnosed from 2008-2023; among these, 175 receiving 2-6 cycles of 1L-CT followed by ICI therapy. Patients were categorized based on response to 1L-CT using the Response Evaluation Criteria in Solid Tumors (v1.1). Objective response rate on ICI, progression to ICI-free survival (ICI-PFS), and overall survival from start of 1L-CT were compared between avelumab-treated and pembrolizumab-treated patients in each response subgroup. RESULTS: ICI-PFS was significantly longer in patients achieving partial response on 1L-CT and subsequently receiving pembrolizumab compared to those receiving avelumab. Notably, patients achieving SD on 1L-CT and subsequently receiving pembrolizumab manifested significantly higher objective response rate (14% and 41%, respectively) and prolonged ICI-PFS relative to those receiving avelumab. In contrast, overall survival did not delineate difference between patients treated with avelumab versus pembrolizumab. Similar findings were discerned in the subanalysis of patients having favorable SD (tumor shrinkage, from - 29 to 0%) and unfavorable SD (tumor enlargement, from + 1 to + 19%) on 1L-CT. CONCLUSIONS: Our study provides real-world evidence regarding difference of oncological efficacy between maintenance avelumab and subsequent pembrolizumab in patients with mUC who achieved partial response or SD on 1L-CT.

Changes in outcome of patients with advanced non-clear cell renal cell carcinoma from the tyrosine kinase inhibitor era to the immuno-oncology era.

BACKGROUND: The therapeutic benefit of immuno-oncology (IO) therapy for patients with advanced non-clear-cell renal cell carcinoma (nccRCC) remains unclear. PATIENTS AND METHODS: We reviewed clinical data from 93 patients with advanced nccRCC who received first-line systemic therapy including IO combination therapy and tyrosine kinase inhibitor (TKI) monotherapy at our affiliated institutions. Patients were divided based on the period when the treatment was implemented as the standard of care into the IO and TKI eras. Survival and tumor response outcomes were compared between the IO and TKI eras. RESULTS: Of the 93 patients, 50 (54%) and 43 (46%) were categorized as IO era and TKI era groups, respectively. Progression-free survival (PFS) and overall survival (OS) were significantly longer in the IO era than in the TKI era (median PFS: 8.97 vs. 4.96 months, p = 0.0152; median OS: 38.4 vs. 13.5 months, p = 0.0001). After the adjustment using other covariates, the treatment era was an independent factor for PFS (hazard ratio: 0.59, p = 0.0235) and OS (hazard ratio: 0.27, p < 0.0001). Objective response and disease control rates was not significantly different between the treatment eras (26% vs. 16.3%, p = 0.268; 62% vs. 62.8%, p = 0.594). CONCLUSION: The implementation of IO therapy was significantly associated with longer survival in the nccRCC population. Further studies are needed to establish a more effective treatment strategy in this population using multiple regimens of IO combination therapy.

Real-World Evidence of Tumor and Patient Characteristics and Survival with Avelumab Maintenance after Chemotherapy for Advanced and Metastatic Urothelial Carcinoma.

INTRODUCTION: Despite the prospective randomized controlled JAVELIN Bladder 100 trial, no real-world evidence exists regarding tumor characteristics, adverse events (AEs), and survival of avelumab maintenance (AVM)-treated patients with partial/complete response or stable disease after previous platinum-based chemotherapy for advanced/metastatic urothelial carcinoma (mUC). METHODS: We relied on our institutional database to identify mUC patients who received AVM between January, 2021 and December, 2023. The main outcomes consisted of overall survival (OS) and progression-free survival (PFS) and were computed by Kaplan-Meier estimates. Stratification was performed according to programmed death ligand 1 (PD-L1) status. RESULTS: Overall, 24 AVM patients were identified at a median age of 71 (interquartile range [IQR]: 67-76) years, of which 67% were males. Of these, 63%, 21%, and 17% received AVM therapy for bladder cancer and upper tract urothelial carcinoma or both, respectively. PD-L1 status was positive in 45% of patients. During AVM treatment, AEs were observed in 33% of patients; however, they were limited to ≤2 grade AEs. At a median follow-up of eight (IQR 4-20) months, 71% of patients had progressed under AVM with median PFS of 6.2 months (confidence interval [CI]: 3.2-18.2). Median OS was 13.4 (CI: 6.9 - not reached [NR]) months. One-year OS after AVM was 52%. In PD-L1-positive patients, median PFS and OS were 6.4 (CI: 2.7 - NR) months and 13.4 (CI: 7.7 months - NR), respectively. CONCLUSION: AVM is associated with moderate AE rates. Despite similarities in baseline characteristics compared to trial-selected JAVELIN Bladder 100 mUC patients, AVM resulted in longer/similar PFS but significantly shorter OS in real-world setting.

J-AVENUE: A retrospective, real-world study evaluating patient characteristics and outcomes in patients with advanced urothelial carcinoma treated with avelumab first-line maintenance therapy in Japan.

OBJECTIVES: The JAVELIN Bladder 100 phase 3 trial showed that avelumab first-line maintenance + best supportive care significantly prolonged overall survival and progression-free survival versus best supportive care alone in patients with advanced urothelial carcinoma who were progression-free following first-line platinum-based chemotherapy. We report findings from J-AVENUE (NCT05431777), a real-world study of avelumab first-line maintenance therapy in Japan. METHODS: Medical charts of patients with advanced urothelial carcinoma without disease progression following first-line platinum-based chemotherapy, who received avelumab maintenance between February and November 2021, were reviewed. Patients were followed until June 2022. The primary endpoint was patient characteristics; secondary endpoints included time to treatment failure and progression-free survival. RESULTS: In 79 patients analyzed, median age was 72 years (range, 44-86). Primary tumor site was upper tract in 45.6% and bladder in 54.4%. The most common first-line chemotherapy regimen was cisplatin + gemcitabine (63.3%). Median number of chemotherapy cycles received was four. Best response to chemotherapy was complete response in 10.1%, partial response in 58.2%, and stable disease in 31.6%. Median treatment-free interval before avelumab was 4.9 weeks. With avelumab first-line maintenance therapy, the disease control rate was 58.2%, median time to treatment failure was 4.6 months (95% CI, 3.3-6.4), and median progression-free survival was 6.1 months (95% CI, 3.6-9.7). CONCLUSIONS: Findings from J-AVENUE show the effectiveness of avelumab first-line maintenance in patients with advanced urothelial carcinoma in Japan in clinical practice, with similar progression-free survival to JAVELIN Bladder 100 and previous real-world studies, supporting its use as a standard of care.

Avelumab to treat Merkel cell carcinoma: real-life experience in a dedicated oncology center. / Avelumab en el tratamiento del carcinoma de células de Merkel: experiencia en vida real en un centro monográfico oncológico.

The arrival of immunotherapy has revolutioned the management of patients with metastatic Merkel cell carcinoma (MCC). We conducted an observational, retrospective study of 14 cases treated with avelumab. The response rate was 57%: complete response was reached in 29% of patients, and partial responses in 29%. The drug proved effective in 83% (5/6) of the patients with a single metastatic site. However, the disease progressed in 75% (3/4) of the patients with bone metastases. PD1-L expression, MCC polyomavirus (MCPyV) positivity, and an impaired neutrophil-to-lypmhocyte ratio (NLR) could not be associated with responses to the therapy. Avelumab is an effective and safe drug for the management of advanced MCC, and its effectiveness appears to be impacted by the number and location of metastases.

Avelumab in Patients With Metastatic Colorectal Cancer.

BACKGROUND: Metastatic colorectal cancer (mCRC) is incurable, and median overall survival is less than 2½ years. Although monoclonal antibodies that block PD-1/PD-L1 interactions are active in microsatellite unstable/mismatch repair deficient tumors, a growing dataset shows that most patients with microsatellite stable/mismatch repair proficient tumors will not benefit from the blockade of PD-1/PD-L1 interactions. Here we present results from patients with mCRC (n = 22) treated with the anti-PD-L1 monoclonal antibody avelumab. METHODS: Patients received treatment on a phase I, open-label, dose-escalation trial via a consecutive parallel-group expansion in colorectal cancer. Patients aged 18 years and older with mCRC measurable by RECIST v1.1 who had received at least 1 line of systemic therapy for metastatic disease enrolled. Patients with prior immune checkpoint inhibitor treatment were excluded. Patients received avelumab 10 mg/kg intravenously every 2 weeks. The primary endpoint was the objective response rate. RESULTS: Twenty-two participants received treatment from July 2013 to August 2014. There were no objective responses and median progression-free survival was 2.1 months (95% CI: 1.4-5.5 months). There were 5 grade 3 treatment-related adverse events: GGT elevation (n = 2), PRESS (n = 1), lymphopenia (n = 1), and asymptomatic amylase/lipase elevation (n = 1). CONCLUSION: As demonstrated with other anti-PD-1/PD-L1 monoclonal antibodies, avelumab is not active in unselected patients with mCRC (ClinicalTrials.gov Identifier: NCT01772004).

Black Patients with Metastatic Castrate-Resistant Prostate Cancer Have a Shorter Time Interval Between PSA and Clinical Progression on Novel Hormonal Therapies plus Avelumab.

BACKGROUND: Black men are at higher risk for prostate cancer death. Previous studies showed a benefit of different therapies, including immune-based therapy, for Black men with metastatic prostate cancer. We sought to explore the efficacy of the PD-L1 inhibitor avelumab in Black men with metastatic castrate-resistant prostate cancer (mCRPC) progressing after abiraterone or enzalutamide. METHODS: This pilot phase II study enrolled self-identified Black patients who developed mCRPC on next-generation hormonal therapies (NHTs) abiraterone acetate or enzalutamide (NCT03770455). Enrolled patients received avelumab 10mg/kg IV every 2 weeks while remaining on the same NHTs. The primary endpoint of our study was ≥ 50% reduction in prostate specific antigen (PSA) at ≥8 weeks. RESULTS: A total of eight patients were enrolled. The median duration on NHTs prior to enrollment was 364 days (95% CI, 260.9-467.1). The median time to initiate avelumab was 8 days (3-14). With a median follow-up of 196 days, no patients achieved the primary endpoint. The median time to PSA progression was 35 days (95 CI%, 0-94.8) and the median time to radiographic and/or clinical progression was 44 days (95 CI%, 0-118.5). The study was closed prematurely due to safety concerns related to the rapid clinical progression observed in the patients enrolled on study. CONCLUSION: In conclusion, the addition of avelumab to NHT did not demonstrate clinical activity in Black men with new mCRPC. The unexpected short interval between PSA and radiographic and/or clinical progression observed in this study has potential clinical implications.ClinicalTrials.gov Identifier: NCT03770455 (IND number 139559).

Phase I Trial of Combination Therapy With Avelumab and Cabozantinib in Patients With Newly Diagnosed Metastatic Clear Cell Renal Cell Carcinoma.

BACKGROUND: Combination immunotherapy is now considered the standard first-line therapy for patients with metastatic clear cell renal cell carcinoma (mccRCC) after multiple clinical trials demonstrated improved overall survival compared with single-agent tyrosine kinase inhibitors. Cabozantinib modulates critical components of the immune system, such as decreasing regulatory T cells and increasing T-effector cell populations, and is approved for the treatment of mRCC. Avelumab is a human IgG1 monoclonal antibody that binds to programmed death-ligand 1 protein and inhibits the interaction with PD-1. This phase I trial assessed the safety and clinical activity of avelumab and cabozantinib combination therapy in mccRCC. METHODS: This study was a phase I, 3+3 dose escalation clinical trial. The primary endpoint was the safety and identification of the recommended phase II dose (RP2D). Secondary endpoints included objective response rate (ORR) and radiographic progression-free survival (rPFS). There were 3 dose cohorts: cabozantinib 20, 40, and 60 mg/day, each combined with avelumab (10 mg/kg intravenously every 2 weeks). An additional 3 patients were included in the final dose cohort as a confirmation of the RP2D. No dose modifications were allowed for avelumab, but dose delays were permitted. Both dose reductions and holds were allowed for cabozantinib. Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, was used to determine ORR, and treatment beyond progression was allowed. RESULTS: Twelve patients with newly diagnosed mccRCC were enrolled from July 2018 until March 2020. Three patients were enrolled in the 20 and 40 mg cohorts each, and 6 were enrolled in the 60 mg cohort. The International Metastatic RCC Database Consortium (IMDC) risk categories for these patients were: 4 patients (favorable risk), 6 patients (intermediate risk), and 2 patients (poor risk). No dose-limiting toxicities (DLTs) were observed in any cohort. Six patients developed serious adverse events related to study treatment after the DLT window period. Immune-related adverse events (iRAEs) were reported in 11 patients; fatigue and diarrhea were the most common (each with n = 4, 33.3%), followed by maculopapular rash and hand-foot syndrome (each with n = 3, 25%). Dose reductions were required in 5 of 6 patients in the cabozantinib 60 mg cohort after the DLT period. One patient discontinued avelumab due to irAE (nephritis), while none discontinued cabozantinib due to toxicity. The ORR was 50%, with one complete response (CR) and 5 partial responses (PR). The disease control rate (CR + PR + stable disease) was noted in 92% of the patients. Radiological PFS survival rate at 6 and 12 months was reported in 67.7% and 33.5% of patients, respectively. CONCLUSION: Combination therapy with avelumab and cabozantinib is safe and showed preliminary clinical activity in mccRCC. Even though the DLT was not met in any of the 3 cohorts, the recommended RP2D dose for the combination is cabozantinib 40 mg/day due to a high incidence of grade 2 toxicity for cabozantinib 60 mg/day after the DLT period. (ClinicalTrials.gov Identifier: NCT03200587).

Switch-maintenance avelumab immunotherapy following first-line chemotherapy for patients with advanced, unresectable or metastatic urothelial carcinoma: the first Japanese real-world evidence from a multicenter study.

OBJECTIVE: To develop the first Japanese real-world evidence of switch-maintenance avelumab in advanced, unresectable or metastatic urothelial carcinoma (aUC). METHODS: A multicenter-derived database registered 505 patients diagnosed with aUC between 2008 and 2021. Of these, 204 patients (40%) were selected and stratified according to the type of therapy used: maintenance avelumab group (27 [5.3%]), second-line (2 L) pembrolizumab group (103 [20%]) and 2 L cytotoxic chemotherapy group (74 [15%]). The progression-free survival and overall survival from the initiation of following therapy were compared. Tumor response was evaluated based on the Response Evaluation Criteria in Solid Tumors guideline v1.1 during the treatment period. A detailed analysis was performed in the maintenance avelumab group to investigate possible factors associated with response to avelumab therapy. RESULTS: The maintenance avelumab group had a longer overall survival, not progression-free survival, compared with the other two treatment groups. The median treatment-free interval between the last dose of first-line (1 L) chemotherapy and the initiation of avelumab therapy was 6 weeks (range, 3-22). Disease control rate of maintenance avelumab therapy in patients with a treatment-free interval of ≤6 weeks was higher than that in patients with a treatment-free interval of >6 weeks (77 vs 40%, P = 0.029). The patients showing objective response to 1 L chemotherapy were less likely to experience tumor relapse (4 of 19) after the initiation of avelumab therapy compared with those showing stable disease (7 of 8). CONCLUSIONS: Objective response to 1 L chemotherapy and early induction of maintenance avelumab therapy may be associated with increased benefit from maintenance avelumab therapy.