Phase 1b study to assess the safety, tolerability, and clinical activity of pamiparib in combination with temozolomide in patients with locally advanced or metastatic solid tumors.

BACKGROUND: Pamiparib is a potent, selective, poly (ADP-ribose) polymerase 1/2 inhibitor that demonstrates synthetic lethality in cells with breast cancer susceptibility gene mutations or other homologous recombination deficiency. This two-stage phase 1b study (NCT03150810) assessed pamiparib in combination with temozolomide (TMZ) in adult patients with histologically confirmed locally advanced and metastatic solid tumors. METHODS: Oral pamiparib 60 mg was administered twice daily. During the dose-escalation stage, increasing doses of TMZ (40-120 mg once daily pulsed or 20-40 mg once daily continuous) were administered to determine the recommended dose to be administered in the dose-expansion stage. The primary objectives were to determine safety and tolerability, maximum tolerated/administered dose, recommended phase 2 dose and schedule, and antitumor activity of pamiparib in combination with TMZ. Pharmacokinetics of pamiparib and TMZ and biomarkers were also assessed. RESULTS: Across stages, 139 patients were treated (dose escalation, n = 66; dose expansion, n = 73). The maximum tolerated dose of TMZ, which was administered during dose expansion, was 7-day pulsed 60 mg once daily. The most common treatment-emergent adverse events (TEAEs) were anemia (dose escalation, 56.1%; dose expansion, 63.0%), nausea (dose escalation, 54.5%; dose expansion, 49.3%), and fatigue (dose escalation, 48.5%; dose expansion, 47.9%). In the dose-escalation stage, four patients experienced dose-limiting toxicities (three neutropenia and one neutrophil count decreased). No TEAEs considered to be related to study drug treatment resulted in death. Antitumor activity was modest, indicated by confirmed overall response rate (dose escalation, 13.8%; dose expansion, 11.6%), median progression-free survival (3.7 and 2.8 months), and median overall survival (10.5 and 9.2 months). Administration of combination therapy did not notably impact pamiparib or TMZ pharmacokinetics. CONCLUSIONS: Pamiparib in combination with TMZ had a manageable safety profile. Further investigation of the efficacy of this combination in tumor types with specific DNA damage repair deficiencies is warranted.

Association of Tumor-informed Circulating Tumor DNA Detectability Before and After Radical Cystectomy with Disease-free Survival in Patients with Bladder Cancer.

BACKGROUND AND OBJECTIVE: Despite curative-intent radical cystectomy (RC), patients with muscle-invasive bladder cancer (MIBC) are at high risk of recurrence. Biomarkers are urgently needed to refine prognostication and selection of appropriate perioperative systemic therapies. Our aim was to evaluate the prognostic and predictive value of tumor-informed circulating tumor DNA (ctDNA) results in a multicenter cohort of patients with bladder cancer who underwent RC. METHODS: We performed a retrospective analysis of real-world data for a commercial ctDNA test (Signatera; Natera, Austin, TX, USA) performed in 167 patients (852 plasma samples) before RC and during molecular residual disease (MRD; adjuvant decision) and surveillance windows. We assessed the correlation between recurrence and ctDNA status before and after RC using Cox regression analysis. RESULTS AND LIMITATIONS: During study-defined postoperative MRD and surveillance windows, detectable ctDNA was associated with shorter disease-free survival (DFS) when compared to undetectable ctDNA (MRD: hazard ratio 6.93; p < 0.001; surveillance: hazard ratio 23.02; p < 0.001). Of note, patients with undetectable ctDNA did not appear to benefit from adjuvant therapy (p = 0.34). Detectable ctDNA in the pre-RC (p = 0.045), MRD (p = 0.002), and surveillance (p < 0.001) windows was the only risk factor independently associated with shorter DFS. Limitations include the retrospective and nonrandomized nature of the study. CONCLUSIONS: ctDNA testing in patients with bladder cancer undergoing RC was prognostic and potentially predictive. Identification of patients at high risk of recurrence may aid in patient counseling and decision-making. PATIENT SUMMARY: We found that outcomes for patients with muscle-invasive bladder cancer are strongly linked to detection of tumor DNA in blood samples. The results show the value of tumor-informed testing for tumor DNA in blood for decisions on the best treatment for each individual patient.

Urine scRNAseq reveals new insights into the bladder tumor immune microenvironment.

Due to bladder tumors' contact with urine, urine-derived cells (UDCs) may serve as a surrogate for monitoring the tumor microenvironment (TME) in bladder cancer (BC). However, the composition of UDCs and the extent to which they mirror the tumor remain poorly characterized. We generated the first single-cell RNA-sequencing of BC patient UDCs with matched tumor and peripheral blood mononuclear cells (PBMC). BC urine was more cellular than healthy donor (HD) urine, containing multiple immune populations including myeloid cells, CD4+ and CD8+ T cells, natural killer (NK) cells, B cells, and dendritic cells (DCs) in addition to tumor and stromal cells. Immune UDCs were transcriptionally more similar to tumor than blood. UDCs encompassed cytotoxic and activated CD4+ T cells, exhausted and tissue-resident memory CD8+ T cells, macrophages, germinal-center-like B cells, tissue-resident and adaptive NK cells, and regulatory DCs found in tumor but lacking or absent in blood. Our findings suggest BC UDCs may be surrogates for the TME and serve as therapeutic biomarkers.

Natural Killer Cell Dysfunction In Human Bladder Cancer Is Caused By Tissue-Specific Suppression of SLAMF6 Signaling.

NK cells are innate lymphocytes critical for surveillance of viruses and tumors, however the mechanisms underlying NK cell dysfunction in cancer are incompletely understood. We assessed the effector function of NK cells from bladder cancer patients and found severe dysfunction in NK cells derived from tumors versus peripheral blood. While both peripheral and tumor-infiltrating NK cells exhibited conserved patterns of inhibitory receptor over-expression, this did not explain the observed defects in NK surveillance in bladder tumors. Rather, TME-specific TGF-ß and metabolic perturbations such as hypoxia directly suppressed NK cell function. Specifically, an oxygen-dependent reduction in signaling through SLAMF6 was mechanistically responsible for poor NK cell function, as tumor-infiltrating NK cells cultured ex vivo under normoxic conditions exhibited complete restoration of function, while deletion of SLAMF6 abrogated NK cell cytolytic function even under normoxic conditions. Collectively, this work highlights the role of tissue-specific factors in dictating NK cell function, and implicates SLAMF6 signaling as a rational target for immuno-modulation to improve NK cell function in bladder cancer.

Advancements in Urothelial Cancer Care: Optimizing Treatment for Your Patient.

The standard treatment paradigm for muscle invasive bladder cancer has been neoadjuvant cisplatin-based chemotherapy followed by radical cystectomy. However, efforts are ongoing to personalize treatment by incorporating biomarkers to better guide treatment selection. In addition, bladder preservation strategies are aimed at avoiding cystectomy in well-selected patients. Similarly, in the metastatic urothelial cancer space, the standard frontline treatment option of platinum-based chemotherapy has changed with the availability of data from EV-302 trial, making the combination of enfortumab vedotin (EV) and pembrolizumab the preferred first-line treatment option. Here, we examine the optimization of treatment intensity and sequencing, focusing on the challenges and opportunities associated with EV/pembrolizumab therapy, including managing toxicities and exploring alternative dosing approaches. Together, these articles provide a comprehensive overview of contemporary strategies in bladder cancer management, highlighting the importance of individualized treatment approaches, ongoing research, and multidisciplinary collaboration to improve patient outcomes in this complex disease landscape.

Single-cell transcriptomic-informed deconvolution of bulk data identifies immune checkpoint blockade resistance in urothelial cancer.

Interactions within the tumor microenvironment (TME) significantly influence tumor progression and treatment responses. While single-cell RNA sequencing (scRNA-seq) and spatial genomics facilitate TME exploration, many clinical cohorts are assessed at the bulk tissue level. Integrating scRNA-seq and bulk tissue RNA-seq data through computational deconvolution is essential for obtaining clinically relevant insights. Our method, ProM, enables the examination of major and minor cell types. Through evaluation against existing methods using paired single-cell and bulk RNA sequencing of human urothelial cancer (UC) samples, ProM demonstrates superiority. Application to UC cohorts treated with immune checkpoint inhibitors reveals pre-treatment cellular features associated with poor outcomes, such as elevated SPP1 expression in macrophage/monocytes (MM). Our deconvolution method and paired single-cell and bulk tissue RNA-seq dataset contribute novel insights into TME heterogeneity and resistance to immune checkpoint blockade.

Novel bladder-sparing approaches in patients with muscle-invasive bladder cancer.

The pursuit of surgeons and oncologists in fulfilling the inherent desire of patients to retain their urinary bladder despite having muscle-invasive bladder cancer (MIBC) has sparked years of research and multiple debates, given its aggressive nature and the high risk of fatal metastatic recurrence. Historically, several approaches to bladder-sparing treatment have been explored, ranging from radical transurethral resection to concurrent chemoradiation. A less well-established approach involves a risk-adapted approach with local therapy deferred based on the clinical response to transurethral resection followed by systemic therapy. Each approach is associated with potential risks, benefits, and trade-offs. In this review, we aim to understand, navigate, and suggest future perspectives on bladder-sparing approaches in patients with MIBC.

C-reactive protein (CRP) as a prognostic biomarker in patients with urothelial carcinoma: A systematic review and meta-analysis.

C-reactive protein (CRP) may reflect a pro-inflammatory tumor microenvironment and could represent a biomarker to select patients with urothelial carcinoma more likely to benefit from therapies directed at modulating tumor-promoting inflammation. We performed a systematic review to evaluate survival outcomes based on pre-treatment CRP values in urothelial carcinoma. The hazard ratios (HRs) of survival such as overall survival (OS) and progression-free survival (PFS) between groups with high versus low CRP values were pooled by the random-effect model meta-analyses. Overall, 28 studies comprising 6789 patients were identified for meta-analyses. High CRP levels were associated with shorter OS (HR=1.96 [95% CI: 1.64-2.33], p < 0.01), particularly in advanced disease treated with immune checkpoint blockade (ICB, HR=1.78 [1.47-2.15], p < 0.01). Similar findings were observed in ICB-treated patients with PFS. These findings suggest that CRP could be an attractive biomarker to select patients with urothelial carcinoma for strategies seeking to modulate tumor-promoting inflammation.

Cooperativity of c-MYC with Krüppel-Like Factor 6 Splice Variant 1 induces phenotypic plasticity and promotes prostate cancer progression and metastasis.

Metastasis remains a major cause of morbidity and mortality in men with prostate cancer, and the functional impact of the genetic alterations, alone or in combination, driving metastatic disease remains incompletely understood. The proto-oncogene c-MYC, commonly deregulated in prostate cancer. Transgenic expression of c-MYC is sufficient to drive the progression to prostatic intraepithelial neoplasia and ultimately to moderately differentiated localized primary tumors, however, c-MYC-driven tumors are unable to progress through the metastatic cascade, suggesting that a "second-hit" is necessary in the milieu of aberrant c-MYC-driven signaling. Here, we identified cooperativity between c-MYC and KLF6-SV1, an oncogenic splice variant of the KLF6 gene. Transgenic mice that co-expressed KLF6-SV1 and c-MYC developed progressive and metastatic prostate cancer with a histological and molecular phenotype like human prostate cancer. Silencing c-MYC expression significantly reduced tumor burden in these mice supporting the necessity for c-MYC in tumor maintenance. Unbiased global proteomic analysis of tumors from these mice revealed significantly enriched vimentin, a dedifferentiation and pro-metastatic marker, induced by KLF6-SV1. c-MYC-positive tumors were also significantly enriched for KLF6-SV1 in human prostate cancer specimens. Our findings provide evidence that KLF6-SV1 is an enhancer of c-MYC-driven prostate cancer progression and metastasis, and a correlated genetic event in human prostate cancer with potential translational significance.

CREST: phase III study of sasanlimab and Bacillus Calmette-Guérin for patients with Bacillus Calmette-Guérin-naïve high-risk non-muscle-invasive bladder cancer.

Bacillus Calmette-Guérin (BCG) is the standard of care for patients with high-risk non-muscle-invasive bladder cancer (NMIBC) after transurethral resection of bladder tumor (TURBT). BCG in combination with programmed cell death-1 (PD-1) inhibitors may yield greater anti-tumor activity compared with either agent alone. CREST is a phase III study evaluating the efficacy and safety of the subcutaneous PD-1 inhibitor sasanlimab in combination with BCG for patients with BCG-naive high-risk NMIBC. Eligible participants are randomized to receive sasanlimab plus BCG (induction ± maintenance) or BCG alone for up to 25 cycles within 12 weeks of TURBT. The primary outcome is event-free survival. Secondary outcomes include additional efficacy end points and safety. The target sample size is around 1000 participants.

Non-muscle-invasive bladder cancer (NMIBC) is the most common type of bladder cancer. Most people have surgery to remove the cancer cells while leaving the rest of the bladder intact. This is called transurethral resection of a bladder tumor (TURBT). For people with high-risk NMIBC, a medicine called Bacillus Calmette-Guérin (BCG) is placed directly inside the bladder after TURBT. A 'high risk' classification means that the cancer is more likely to spread or come back after treatment. Some people's cancer does not respond to BCG or returns after BCG treatment. Researchers are currently looking at whether BCG combined with other immunotherapies may prevent cancer growth more than BCG on its own. Immunotherapy helps the immune system recognize and kill cancer cells. Sasanlimab is an immunotherapy medicine that is not yet approved to treat people with NMIBC. It is given as an injection under the skin. In this CREST study, researchers are looking at how safe and effective sasanlimab plus BCG is for people with high-risk NMIBC. Around 1000 people are taking part in CREST. They must have had TURBT 12 weeks or less before joining the study. Researchers want to know how long people live without certain events occurring, such as bladder cancer cells returning. A plain language summary of this article can be found as Supplementary Material. Clinical Trial Registration: NCT04165317; 2019-003375-19 (EudraCT) (ClinicalTrials.gov).

Immunomodulatory effects and improved outcomes with cisplatin- versus carboplatin-based chemotherapy plus atezolizumab in urothelial cancer.

In metastatic urothelial cancer (mUC), cisplatin versus carboplatin leads to durable disease control in a subset of patients. The IMvigor130 trial reveals more favorable effects with atezolizumab combined with gemcitabine and cisplatin (GemCis) versus gemcitabine and carboplatin (GemCarbo). This study investigates the immunomodulatory effects of cisplatin as a potential explanation for these observations. Our findings indicate that improved outcomes with GemCis versus GemCarbo are primarily observed in patients with pretreatment tumors exhibiting features of restrained adaptive immunity. In addition, GemCis versus GemCarbo ± atezolizumab induces transcriptional changes in circulating immune cells, including upregulation of antigen presentation and T cell activation programs. In vitro experiments demonstrate that cisplatin, compared with carboplatin, exerts direct immunomodulatory effects on cancer cells, promoting dendritic cell activation and antigen-specific T cell killing. These results underscore the key role of immune modulation in cisplatin's efficacy in mUC and highlight the importance of specific chemotherapy backbones in immunotherapy combination regimens.

Phase 2 trial of tremelimumab in patients with metastatic urothelial cancer previously treated with programmed death 1/programmed death ligand 1 blockade.

INTRODUCTION: Programmed death 1 (PD-1)/programmed death ligand 1 (PD-L1) blockade has changed the landscape of treatment for metastatic urothelial cancer, but single-agent cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) blockade in metastatic urothelial cancer has been underexplored. A prior phase 2 trial of tremelimumab in PD-1/PD-L1-blockade naive patients with metastatic urothelial cancer revealed activity comparable to that observed with PD-1/PD-L1 blockade raising the hypothesis that these classes of immune checkpoint inhibitors might be non-cross-resistant. METHODS: The current phase 2 trial treated patients with PD-1/PD-L1 blockade-resistant metastatic urothelial cancer with single-agent tremelimumab (750 mg intravenously every 28 days for up to 7 cycles). The primary end point was objective response rate. RESULTS: Twenty-six patients were enrolled and 24 patients were evaluable for response. The objective response rate was 8.3%, composed of a total of two partial responses that lasted 10.9 and 24.0 months. Stable disease was observed in another 20.8% of patients, with a median duration of stable disease of 5.4 months. Diarrhea occurred in 15 patients (58%), elevated hepatic transaminases occurred in seven patients (27%), and adrenal insufficiency occurred in two patients (8%); one patient died after experiencing immune-related hepatitis. CONCLUSIONS: High dose CTLA-4 blockade in patients with PD-1/PD-L1-resistant metastatic urothelial cancer has modest activity and is associated with treatment-related toxicity similar to prior reports.

Turning up the heat: CTLA4 blockade in urothelial cancer.

Anti-PD1 and anti-PDL1 monotherapies have shown clinical efficacy in stage IV urothelial cancer and are integrated into current clinical practice. However, only a small number of the patients treated with single-agent checkpoint blockade experience an antitumour response. Insufficient priming or inhibitory factors in the tumour immune microenvironment might have a role in the lack of response. CTLA4 is an inhibitory checkpoint on activated T cells that is being studied as a therapeutic target in combination with anti-PD1 or anti-PDL1 therapies in advanced urothelial cancer. In locally advanced urothelial cancer, this combination approach has shown encouraging antitumour effects when administered pre-operatively. We believe that the presence of pre-existing intratumoural T cell immunity is not a prerequisite for response to combination therapy and that the additional value of CTLA4 blockade might involve the broadening of peripheral T cell priming, thereby transforming immunologically cold tumours into hot tumours.

A SEER-Medicare Based Quality Score for Patients With Metastatic Upper Tract Urothelial Carcinoma.

BACKGROUND: Population-based studies evaluating outcomes for metastatic upper tract urothelial carcinoma (mUTUC) are sparse and rarely capture both patients with de novo (synchronous) metastases and those who progress to metastatic disease (metachronous). Herein we evaluated the outcomes and costs associated with synchronous and metachronous mUTUC, utilizing a novel Methodology. Additionally, we created a guideline-based quality score to improve care in this space. PATIENTS AND METHODS: We identified all patients with mUTUC aged 66 years and older included in the SEER-Medicare linked database between 2004 and 2012. Achievement of 3 quality criteria was assessed: (1) cancer-specific survival (CSS)>12 months; (2) receipt of systemic therapy; (3) receipt of hospice/palliative care. Total healthcare and out-of-pocket costs were evaluated. Regression analyses were performed to assess characteristics associated with quality criteria and total healthcare costs. RESULTS: Of the 1223 patients identified, at least one quality criterion was met in just 40.2% and only 54 patients (4.4%) received palliative care. In multivariable analysis, patients with synchronous mUTUC (OR:0.55, 95%CI:0.41-0.72), and at least 3 comorbidities (OR:0.68, 95%CI:0.47-0.98) were less likely to achieve at least 1 quality criterion. Meeting at least 1 quality criterion was associated with increased costs ($94,677, 95%CI:87,702-101,652 versus $63,575, 95%CI:59,598-67,552). CONCLUSIONS: Less than half of patients with mUTUC met at least 1 quality criterion. Quality score achievement was associated with a modest increase in total healthcare spending. These findings not only provide guidance for future study of rare diseases using secondary data, but also highlight inadequacies in the current management of mUTUC.

Atezolizumab plus chemotherapy versus placebo plus chemotherapy in untreated locally advanced or metastatic urothelial carcinoma (IMvigor130): final overall survival analysis results from a randomised, controlled, phase 3 study.

BACKGROUND: IMvigor130 demonstrated statistically significant investigator-assessed progression-free survival benefit with first-line atezolizumab plus platinum-based chemotherapy (group A) versus placebo plus platinum-based chemotherapy (group C) in patients with locally advanced or metastatic urothelial carcinoma. Overall survival was not improved in interim analyses. Here we report the final overall analysis for group A versus group C. METHODS: In this global, partially blinded, randomised, controlled, phase 3 study, patients (aged ≥18 years) with previously untreated locally advanced or metastatic urothelial cancer and who had an Eastern Cooperative Oncology Group performance status of 0-2 were enrolled at 221 hospitals and oncology centres in 35 countries. Patients were randomly assigned (1:1:1), with a permuted block method (block size of six) and an interactive voice and web response system, stratified by PD-L1 status, Bajorin risk factor score, and investigator's choice of platinum-based chemotherapy, to receive atezolizumab plus platinum-based chemotherapy (group A), atezolizumab monotherapy (group B), or placebo plus platinum-based chemotherapy (group C). Sponsors, investigators, and patients were masked to assignment to atezolizumab or placebo (ie, group A and group C) and atezolizumab monotherapy (group B) was open label. For groups A and C, all patients received gemcitabine (1000 mg/m2 intravenously; day 1 and day 8 of each 21-day cycle), plus investigator's choice of carboplatin (area under curve 4·5 mg/mL per min or 5 mg/mL per min; intravenously) or cisplatin (70 mg/m2 intravenously), plus either atezolizumab (1200 mg intravenously) or placebo on day 1 of each cycle. Co-primary endpoints of the study were investigator-assessed progression-free survival and overall survival for group A versus group C in the intention-to-treat (ITT) population (ie, all randomised patients), and overall survival for group B versus group C, tested hierarchically. Final overall survival and updated safety outcomes (safety population; all patients who received any amount of any study treatment component) for group A versus group C are reported here. The final prespecified boundary for significance of the overall survival analysis was one-sided p=0·021. The trial is registered with ClinicalTrials.gov, NCT02807636, and is active but no longer recruiting. FINDINGS: Between July 15, 2016, and July 20, 2018, 1213 patients were enrolled and randomly assigned to treatment, of whom 851 were assigned to group A (n=451) and group C (n=400). 338 (75%) patients in group A and 298 (75%) in group C were male, 113 (25%) in group A and 102 (25%) in group C were female, and 346 (77%) in group A and 304 (76%) in group C were White. At data cutoff (Aug 31, 2022), after a median follow up of 13·4 months (IQR 6·2-30·8), median overall survival was 16·1 months (95% CI 14·2-18·8; 336 deaths) in group A versus 13·4 months (12·0-15·3; 310 deaths) in group C (stratified hazard ratio 0·85 [95% CI 0·73-1·00]; one-sided p=0·023). The most common grade 3-4 treatment-related adverse events were anaemia (168 [37%] of 454 patients who received atezolizumab plus chemotherapy vs 133 [34%] of 389 who received placebo plus chemotherapy), neutropenia (167 [37%] vs 115 [30%]), decreased neutrophil count (98 [22%] vs 95 [24%]), thrombocytopenia (95 [21%] vs 70 [18%]), and decreased platelet count (92 [20%] vs 92 [24%]). Serious adverse events occurred in 243 (54%) patients who received atezolizumab plus chemotherapy and 196 (50%) patients who received placebo plus chemotherapy. Treatment-related deaths occurred in nine (2%; acute kidney injury, dyspnoea, hepatic failure, hepatitis, neutropenia, pneumonitis, respiratory failure, sepsis, and thrombocytopenia [n=1 each]) patients who received atezolizumab plus chemotherapy and four (1%; unexplained death, diarrhoea, febrile neutropenia, and toxic hepatitis [n=1 each]) who received placebo plus chemotherapy. INTERPRETATION: Progression-free survival benefit with first-line combination of atezolizumab plus platinum-based chemotherapy did not translate into a significant improvement in overall survival in the ITT population of IMvigor130. Further research is needed to understand which patients might benefit from first-line combination treatment. No new safety signals were observed. FUNDING: F Hoffmann-La Roche.

Atezolizumab monotherapy versus chemotherapy in untreated locally advanced or metastatic urothelial carcinoma (IMvigor130): final overall survival analysis from a randomised, controlled, phase 3 study.

BACKGROUND: The primary analysis of IMvigor130 showed a significant progression-free survival benefit with first-line atezolizumab plus platinum-based chemotherapy (group A) versus placebo plus platinum-based chemotherapy (group C) in patients with locally advanced or metastatic urothelial cancer. However, this finding did not translate into significant overall survival benefit for group A versus group C at the final analysis, precluding formal statistical testing of outcomes with atezolizumab monotherapy (group B) versus group C. Here we report the final overall survival results for group B versus group C; this report is descriptive and should be considered exploratory due to the study's statistical design. METHODS: In this global, partially blinded, randomised, controlled, phase 3 study, patients (aged ≥18 years) who had locally advanced or metastatic urothelial cancer previously untreated in the metastatic setting and Eastern Cooperative Oncology Group performance status of 0-2 were enrolled at 221 hospitals and oncology centres in 35 countries. Patients were randomly assigned (1:1:1), using a permuted block method (block size of six) and an interactive voice and web response system, stratified by PD-L1 status, Bajorin score, and investigator's choice of platinum-based chemotherapy, to receive either atezolizumab plus platinum-based chemotherapy (group A), atezolizumab alone (group B), or placebo plus platinum-based chemotherapy (group C). Sponsors, investigators, and patients were masked to assignment to atezolizumab or placebo in group A and group C; atezolizumab monotherapy in group B was open label. For groups B and C, atezolizumab (1200 mg) or placebo was administered intravenously every 3 weeks. Chemotherapy involved 21-day cycles of gemcitabine (1000 mg/m2 body surface area on day 1 and day 8 of each cycle) plus the investigator's choice of carboplatin (area under the curve 4·5 mg/mL per min or 5 mg/mL per min) or cisplatin (70 mg/m2 body surface area), administered intravenously. Co-primary endpoints were progression-free survival and overall survival in group A versus group C, and overall survival in group B versus group C, tested hierarchically, in the intention-to-treat (ITT) population, and then the populations with high PD-L1 tumour expression (immune cell [IC] expression score of IC2/3) if the results from group A versus group C were significant. Here, we report the co-primary endpoint of overall survival for group B versus group C in the ITT and IC2/3 populations. The ITT population for this analysis comprised concurrently enrolled patients in groups B and C who were randomly assigned to treatment. For the safety analysis, all patients enrolled in group B and group C who received any study treatment were included. The trial is registered with ClinicalTrials.gov, NCT02807636, and is active but no longer recruiting. FINDINGS: Between July 15, 2016, and July 20, 2018, 1213 patients were enrolled and randomly assigned to treatment, of whom 362 patients were assigned to group B and 400 to group C, of whom 360 and 359, respectively, were enrolled concurrently (ITT population). 543 (76%) of 719 patients were male, 176 (24%) were female, and 534 (74%) were White. As of data cutoff (Aug 31, 2022), after a median follow-up of 13·4 months (IQR 6·2-30·8), median overall survival was 15·2 months (95% CI 13·1-17·7; 271 deaths) in group B and 13·3 months (11·9-15·6; 275 deaths) in group C (stratified hazard ratio 0·98 [95% CI 0·82-1·16]). The most common grade 3-4 treatment-related adverse events were anaemia (two [1%] in patients who received atezolizumab monotherapy vs 133 [34%] in those who received placebo plus chemotherapy), neutropenia (one [<1%] vs 115 [30%]), decreased neutrophil count (0 vs 95 [24%]), and decreased platelet count (one [<1%] vs 92 [24%]). Serious adverse events occurred in 163 (46%) patients versus 196 (50%). Treatment-related deaths occurred in three (1%; n=1 each, pneumonia, interstitial lung disease, large intestinal obstruction) patients who received atezolizumab monotherapy and four (1%; n=1 each, diarrhoea, febrile neutropenia, unexplained death, toxic hepatitis) who received placebo plus chemotherapy. INTERPRETATION: The final analysis from IMvigor130 did not show a significant improvement in overall survival with first-line atezolizumab monotherapy compared with platinum-based chemotherapy in the intention-to-treat population. The safety profile of atezolizumab monotherapy remained acceptable after extended follow-up, with no new safety signals. FUNDING: F Hoffmann-La Roche.