Unexpected response to cisplatin rechallenge after immune checkpoint inhibitors in patients with metastatic urothelial carcinoma refractory to platinum regimen

Durable Response to Enfortumab Vedotin Compared to Re-challenging Chemotherapy in Metastatic Urothelial Carcinoma After Checkpoint Inhibitors

BACKGROUND

Enfortumab vedotin (EV), an antibody-drug conjugate targeting Nectin-4, has been used for patients with metastatic urothelial carcinoma (mUC) after progressing on checkpoint inhibitors (CPIs). Re-challenging chemotherapy with platinum agents and continuing CPIs beyond progressive disease (PD) have often been chosen following PD on CPIs, and several studies indicate favorable treatment effects of re-challenging chemotherapy. There is little evidence for comparing EV and re-challenging chemotherapy in real-world clinical practice.

OBJECTIVE

The aim was to reveal the real-world treatment outcomes of EV, re-challenging chemotherapy, and continuing CPIs beyond PD in mUC patients.

PATIENTS AND METHODS

A multi-institutional dataset of 350 mUC patients treated with CPIs was utilized. Overall survival (OS), progression-free survival (PFS), objective response rate (ORR), and duration of response (DOR) were evaluated to compare the treatment arms.

RESULTS

One hundred and nine mUC patients were treated with EV with a median follow-up of 6.4 months. The ORR and disease control rate (DCR) were 48% and 70%, respectively. The OS from PD on pembrolizumab exhibited significant differences among the three groups, with a median OS of 8, 14, and 29 months in continuing pembrolizumab beyond PD, re-challenging chemotherapy, and EV, respectively. When comparing the survival outcomes from the initiation of the treatment, there is neither a difference in OS (p = 0.124), PFS (p = 0.936), nor ORR (p = 0.816) between EV and re-challenging chemotherapy. Notably, the DOR in patients who achieved an objective response was significantly longer in the EV group than the re-challenging chemotherapy group (a median of 11 and 5 months, p = 0.049). For OS, the difference was not statistically significant (27 and 11 months in EV and re-challenging chemotherapy, respectively: p = 0.05).

CONCLUSIONS

A superior effect of EV on patient survival compared to re-challenging chemotherapy and continuing pembrolizumab beyond PD was observed in our real-world analysis, which is attributed to the durable DOR in EV treatment despite the similar ORR to re-challenging chemotherapy.

Latest evidence on clinical outcomes and prognostic factors of advanced urothelial carcinoma in the era of immune checkpoint inhibitors: a narrative review

The management of advanced (locally advanced or metastatic) urothelial carcinoma has been revolutionized since pembrolizumab was introduced in 2017. Several prognostic factors for advanced urothelial carcinoma treated with pembrolizumab have been reported, including conventional parameters such as performance status and visceral (especially liver) metastasis, laboratory markers such as the neutrophil-to-lymphocyte ratio, sarcopenia, histological/genomic markers such as programmed cell death ligand 1 immunohistochemistry and tumor mutational burden, variant histology, immune-related adverse events, concomitant medications in relation to the gut microbiome, primary tumor site (bladder cancer versus upper tract urothelial carcinoma) and history/combination of radiotherapy. The survival time of advanced urothelial carcinoma has been significantly prolonged (or 'doubled' from 1 to 2 years) after the advent of pembrolizumab, which will be further improved with novel agents such as avelumab and enfortumab vedotin. This review summarizes the latest evidence on clinical outcomes and prognostic factors of advanced urothelial carcinoma in the contemporary era of immune checkpoint inhibitors.

Enfortumab vedotin versus platinum rechallenge in post-platinum, post-pembrolizumab advanced urothelial carcinoma: A multicenter propensity score-matched study

OBJECTIVE

Enfortumab vedotin (EV) was approved for advanced urothelial carcinoma (UC) in 2021 after the EV-301 trial showed its superiority to non-platinum-based chemotherapy as later-line treatment after platinum-based chemotherapy and immune checkpoint inhibitors including pembrolizumab. However, no study has compared EV with rechallenging platinum-based chemotherapy (i.e., "platinum rechallenge") in that setting.

METHODS

In total, 283 patients received pembrolizumab for advanced UC after platinum-based chemotherapy between 2018 and 2023. Of them, 41 and 25 patients received EV and platinum rechallenge, respectively, as later-line treatment after pembrolizumab. After excluding two patients with EV without imaging evaluation, we compared oncological outcomes, including progression-free survival (PFS) and overall survival (OS), between the EV (n = 39) and platinum rechallenge groups (n = 25) using propensity score matching (PSM).

RESULTS

Analyses on crude data (n = 64) showed no significant differences between the two groups regarding patients' baseline characteristics. PFS (5 months) and OS (11 months) in the EV group were comparable to those (8 and 12 months, respectively) in the platinum rechallenge group. After PSM (n = 36), the baseline characteristics between the two groups became more balanced, and PFS (not reached) and OS (not reached) in the EV group were comparable to those (8 and 11 months, respectively) in the platinum rechallenge group.

CONCLUSIONS

EV and platinum rechallenge showed equivalent oncological outcomes, even after PSM, and both treatments should therefore be effective treatment options for post-platinum, post-pembrolizumab advanced UC.

Treatment Patterns and Efficacy of Chemotherapy After Pembrolizumab in Advanced Urothelial Cancer-a Real-World Study in the pre-Antibody-Drug Conjugate Era

BACKGROUND

Immune checkpoint inhibitors (ICIs) have been established as a routine treatment in patients with metastatic urothelial cancer (mUC). However, there has been no standard of care after progression on ICIs. We investigated real-world treatment patterns and efficacy of chemotherapy (CHT) after pembrolizumab, in the era before introduction of maintenance avelumab and antibody-drug conjugates (ADC).

PATIENTS AND METHODS

An observational, retrospective study was conducted at twelve Nordic centers. Patients with mUC were treated according to investigator´s choice of CHT after pembrolizumab. Primary endpoint was overall response (ORR) and disease control rate (DCR); secondary endpoints were progression-free (PFS) and overall survival (OS).

RESULTS

In total, 102 patients were included whereof 23 patients received CHT after pembrolizumab as second line treatment (subcohort A) and 79 patients in third line (subcohort B). Platinum-gemcitabine combinations were the most common regimens in subcohort A, and vinflunine in subcohort B. The ORR and DCR were 36% and 47%, respectively. Presence of liver metastases was independently associated with lower ORR and DCR. The PFS and OS were 3.3 months and 7.7 months, respectively. Eastern Cooperative Oncology Group Performance Status (ECOG PS) and number of previous cycles of pembrolizumab were found to be independent prognostic factors associated with OS.

CONCLUSION

In a real-world setting, CHT showed clinically meaningful response rates and survival in mUC patients after progression with pembrolizumab. Clinical benefit may primarily be achieved in patients with favorable ECOG PS, in patients treated with > 6 cycles pembrolizumab as well as in patients without presence of liver metastases.

Chemotherapy postimmunotherapy for recurrent metastatic head and neck squamous cell carcinoma

PURPOSE OF REVIEW

Clinical data on salvage chemotherapy used after checkpoints inhibitors in oncology are reviewed, with a special focus on recurrent/metastatic head and neck squamous cell carcinoma (R/M HNSCC).

RECENT FINDINGS

Converging evidence is emerging about high response and/or disease control rates associated with salvage chemotherapy after immunotherapy failure in advanced solid tumours. This phenomenon is mainly reported in retrospective studies for "hot tumours" such as R/M HNSCC, melanoma, lung, urothelial or gastric cancers, but also in haematological malignancies. Some physiopathological hypotheses have been raised.

SUMMARY

Several independent series show increased response rates associated with postimmuno chemotherapy when compared with retrospective series in similar settings. Several mechanisms could be involved such as a "carry-over" allowed by a persistence of the checkpoint inhibitor, a modulation of tumour microenvironment components but also an intrinsic immunomodulatory effect of chemotherapy, increased by a specific immunologic state induced by the therapeutic pressure of checkpoint inhibitors. These data establish a rationale for prospectively evaluating the features of postimmunotherapy salvage chemotherapy.

Re-challenging chemotherapy after pembrolizumab in platinum-refractory urothelial carcinoma

OBJECTIVES

To assess the real-world clinical benefit of re-challenging chemotherapy after pembrolizumab in patients with metastatic urothelial carcinoma (mUC), as there have been several reports suggesting that programmed cell death protein-1/programmed death-ligand 1inhibitors can restore platinum sensitivity.

PATIENTS AND METHODS

Of 236 patients treated with pembrolizumab, we excluded 45 patients who did not experience progressive disease (PD) for pembrolizumab during the follow-up and 86 patients who discontinued pembrolizumab by the diagnosis of PD followed by the best supportive care. A total of 105 patients were identified for a logistic regression propensity score model to compare the survival outcomes between patients treated with continuing pembrolizumab (80) and re-challenging chemotherapy (25) after the diagnosis of PD for pembrolizumab.

RESULTS

A median overall survival (OS) from PD for pembrolizumab was 11 months in 105 patients. Of 25 patients treated with re-challenging chemotherapy, platinum-including chemotherapy (gemcitabine and cisplatin; gemcitabine/cisplatin/paclitaxel [GCP]; methotrexate and vinblastine and adriamycin and cisplatin; and methotrexate and carboplatin and vinblastine MCAVI) was offered in 20 patients (80%). The objective response rate (ORR) for the first-line chemotherapy in the 105 patients was 30%, with a comparable ORR in 25 patients treated with re-challenging chemotherapy of 28%. GCP as a re-challenging regimen was offered in 12 of 25 (48%) patients. The ORR for the GCP regimen was 50%. Propensity score matching was performed using putative clinical factors, from which 34 patients were identified as pair-matched groups. The OS for patients treated with re-challenging chemotherapy was significantly longer than continuing pembrolizumab (a median of 13.9 and 5.8 months, respectively: P = 0.048).

CONCLUSION

Re-challenging chemotherapy including platinum agents after PD with pembrolizumab offers clinical benefits in patients with mUC.

Chemotherapy following immune checkpoint inhibitors in patients with locally advanced or metastatic urothelial carcinoma

BACKGROUND

Recent studies suggest improvements in response to salvage chemotherapy (CT) after immune checkpoint inhibitors (ICIs) in several types of cancer. Our objective was to assess the efficacy of chemotherapy re-challenge after ICI, compared with second-line chemotherapy without previous ICI in patients with locally advanced or metastatic urothelial carcinoma (la/mUC).

METHODS

In this multicentre retrospective study, we included all patients with la/mUC initiating second or third-line chemotherapy from January 2015 to June 2020. We compared patients treated with second-line chemotherapy without previous ICI (CT2) and patients treated with third-line chemotherapy after ICI (CT3). The primary end-point was objective response rate (ORR) in CT3 compared with CT2. Secondary end-points included progression-free survival (PFS) and toxicities.

RESULTS

Overall, 553 patients were included. ORRs were 31.0% (95% CI, 26.5 to 35.5) and 29.2% (95% CI, 21.9 to 36.6), respectively, in CT2 and CT3, with no statistically significant differences (P = 0.62). In subgroup analyses, no differences in ORR were observed by Bellmunt risk group, type of chemotherapy (platinum or taxanes), duration of response to first-platinum-based chemotherapy (< or ≥ 12 months) or FGFR-status. Median PFS was 4.6 months (95% CI, 3.9 to 5.1) and 4.9 months (95% CI, 4.1 to 5.5) in CT2 and CT3, respectively, and grade 3-4 hematologic toxicity occurred in 35.0% and 22.4% of patients.

CONCLUSION

This large multicentre retrospective study provides clinically relevant real-world data. Chemotherapy re-challenge after ICI in la/mUC achieves ORR and PFS comparable with those obtained in CT2 with an acceptable safety profile. These updated results offer more promising outcomes than historically reported with second-line chemotherapy data.

Subsequent Systemic Therapy following Platinum and Immune Checkpoint Inhibitors in Metastatic Urothelial Carcinoma

Treatment of metastatic urothelial carcinoma (mUC) after failure with platinum-based chemotherapy and immune checkpoint inhibitors (ICIs) remains controversial. To explore the role of subsequent systemic therapy, medical records from 436 patients who were consecutively treated with chemotherapy for mUC between May 2017 and April 2021 were collected from a single-center cancer registry. The primary endpoint was overall survival (OS), and progression-free survival (PFS) and response rate (RR) were also assessed. Among the 318 patients who failed both platinum and ICIs, subsequent therapy was delivered to 166 (52%) patients: taxanes (n = 56), platinum rechallenge (n = 46), pemetrexed (n = 39), and clinical trials (n = 25). Objective responses to third-line therapy were noted in 50 patients (RR, 30%; 95% CI, 23–37%). The patients who were enrolled in clinical trials and treated with platinum rechallenge were significantly more likely to respond than those treated with taxanes or pemetrexed. The median PFS and OS were 3.5 months (95% CI, 2.9–4.2 months) and 9.5 months (95% CI, 8.1–11.0 months), respectively. Similar to RR, PFS and OS were longer for the patients who were enrolled in clinical trials. Based on multivariate analyses, good performance status and enrollment in clinical trials are associated with benefits from subsequent therapy for pretreated mUC.

Platinum-Based Chemotherapy 'Rechallenge' in Advanced Non-ovarian Solid Malignancies

Platinum-based chemotherapy forms the backbone of treatment for many solid cancers. However, resistance inevitably develops in those with advanced disease. Platinum rechallenge is a well-established concept in the management of ovarian cancer, small cell lung cancer and germ cell tumours. In other solid malignancies there is a lack of quality evidence to support platinum rechallenge, yet it is a widely adopted strategy. Often, patients are within the last year of life, making questions of efficacy, treatment-related toxicity and quality of life critical factors for treatment recommendations. In this overview we appraise the available evidence for platinum rechallenge and strategies being developed to attempt resensitisation of tumours to platinum-based chemotherapy.

Clinical practice pattern in patients with advanced urothelial cancer who had progressed on pembrolizumab in the pre-enfortumab vedotin era

OBJECTIVES

Pembrolizumab, an anti-PD-1 monoclonal antibody, revolutionized the treatment for advanced urothelial carcinoma. However, the standard treatment for patients after disease progression with pembrolizumab had not been established until the recent approval of enfortumab vedotin. We analyzed the treatment of these patients in the real world, and the patient background and outcomes.

METHODS

We extracted data from 543 patients who experienced progressive disease after pembrolizumab initiation from a Japanese nation-wide cohort of platinum-refractory, metastatic urothelial carcinoma.

RESULTS

The median overall survival of the 543 patients was 3.5 months (95% confidence interval 3.0-4.1). Of these, only 20.6% (n = 112) received chemotherapy as a subsequent systemic treatment after progressive disease. The regimen of chemotherapy was very diverse. The median overall survival was 11.9 months (95% confidence interval 9.2-14.7) for patients who received chemotherapy, compared to 2.4 months for those who did not receive chemotherapy (95% confidence interval 2.1-2.9; P < 0.0001). Patients who received subsequent chemotherapy were more likely to have better performance status, neutrophil-to-lymphocyte ratio <3, hemoglobin >11 mg/dL, and history of a single chemotherapeutic regimen at pembrolizumab initiation.

CONCLUSIONS

This report highlights the real-world practice of the management after pembrolizumab treatment failure in the pre-enfortumab vedotin era, characterized by infrequent use of subsequent anticancer therapy comprising various regimens, reflecting the lack of a standard treatment. Clinical introduction of enfortumab vedotin is expected to improve treatment outcomes in this setting. The present study will provide important baseline data for evaluating the influence of enfortumab vedotin on clinical practices and outcomes.

Metastatic Urothelial Cancer: a rapidly changing treatment landscape

Despite significant progress, metastatic urothelial cancer remains an incurable condition with a limited life expectancy. Platinum-based chemotherapy is still the mainstay of treatment for metastatic disease, but immunotherapy, antibody drug conjugates, and targeted agents have shown encouraging results in several recent practice changing trials. In this review, we discuss the standard of care, recent therapeutic advances, ongoing clinical trials, and future perspectives in metastatic urothelial carcinoma.

Clinical Outcomes of Patients With Metastatic Urothelial Carcinoma After Progression to Immune Checkpoint Inhibitors: A Retrospective Analysis by the Meet-Uro Group (Meet-URO 1 Study)

Background:

Immune checkpoint inhibitors (ICIs) are currently the standard of care for metastatic urothelial cancer (mUC) after the failure of previous platinum-based chemotherapy. The choice of further therapy after ICI progression is a new challenge, and scarce data support it. We aimed to examine the outcomes of mUC patients after progression to ICI, especially when receiving chemotherapy.

Methods:

Data were retrospectively collected from clinical records of mUC patients whose disease progressed to anti-programmed death 1 (PD-1)or programmed death ligand 1 (PD-L1) therapy at 14 Italian centers. Patients were grouped according to ICI therapy setting into SALVAGE (ie, ICI delivered ⩾ second-line therapy after platinum-based chemotherapy) and NAÏVE (ie, first-line therapy) groups. Progression-free survival (PFS) and overall survival (OS) rates were calculated using the Kaplan-Meier method and compared among subgroups. Cox regression assessed the effect of treatments after progression to ICI on OS. Objective response rate (ORR) was calculated as the sum of partial and complete radiologic responses.

Results:

The study population consisted of 201 mUC patients who progressed after ICI: 59 in the NAÏVE cohort and 142 in the SALVAGE cohort. Overall, 52 patients received chemotherapy after ICI progression (25.9%), 20 (9.9%) received ICI beyond progression, 115 (57.2%) received best supportive care only, and 14 (7.0%) received investigational drugs. Objective response rate to chemotherapy in the post-ICI setting was 23.1% (28.0% in the NAÏVE group and 18.5% in the SALVAGE group). Median PFS and OS to chemotherapy after ICI-PD was 5 months (95% confidence interval [CI]: 3-11) and 13 months (95% CI: 7-NA) for the NAÏVE group; 3 months (95% CI: 2-NA) and 9 months (95% CI: 6-NA) for the SALVAGE group, respectively. Overall survival from ICI initiation was 17 months for patients receiving chemotherapy (hazard ratio [HR] = 0.09, p < 0.001), versus 8 months for patients receiving ICI beyond progression (HR = 0.13, p < 0.001), and 2 months for patients who did not receive further active treatment (p < 0.001).

Conclusions:

Chemotherapy administered after ICI progression for mUC patients is advisable irrespective of the treatment line.

Organ-Specific Therapeutic Effect of Paclitaxel and Carboplatin Chemotherapy After Platinum-Based Chemotherapy and Pembrolizumab for Metastatic Urothelial Carcinoma

Background

To evaluate the organ-specific therapeutic effect of paclitaxel and carboplatin (TC) chemotherapy in patients who failed platinum-based chemotherapy and pembrolizumab for metastatic urothelial carcinoma (UC).

Patients and Methods

We retrospectively reviewed the data of patients with metastatic UC who had received TC chemotherapy after the failure of platinum-based chemotherapy and pembrolizumab. The RECIST 1.1 criteria were used to assess the objective response to pembrolizumab and TC chemotherapy at tumor sites.

Results

We analyzed 8 patients (male, n=5; female, n=3; median age, 65 years old). All patients except one had visceral metastasis. The median overall survival for TC was 10.9 months (95% confidence interval, 1.0‑12.7 months), and the objective response rate was 25.0% (partial response [PR]: 2 cases). The metastatic organs were the lymph nodes in 5 cases (number of tumor sites: 8), lung in 4 cases (number of tumor sites: 12), liver in 3 cases (number of tumor sites: 14), bone in 3 cases (number of tumor sites: 12), and primary lesion in 3 cases (number of tumor sites: 3). There were no cases of a complete response or progressive disease in any metastatic organs due to TC chemotherapy. A PR was seen in 2 cases of lymph node metastasis (40.0%), 2 cases of lung metastasis (50.0%), and 2 cases of liver metastasis (66.7%). All 3 cases of bone metastasis showed stable disease, as did all 3 cases of primary lesion. Improvement in the therapeutic effect of TC chemotherapy compared with pembrolizumab was observed in 2 cases (40.0%) of lymph node metastasis, 2 cases (50.0%) of lung metastasis, and 1 case (33.3%) of liver metastasis.

Conclusion

Lymph node, lung, and liver metastases may respond to TC chemotherapy, even if exacerbated with pembrolizumab after platinum-based chemotherapy in metastatic UC.

Clinical outcome after progressing to frontline and second-line Anti-PD-1/PD-L1 in advanced urothelial cancer

BACKGROUND

Immune checkpoint inhibitors (ICIs) are approved for first-line (cisplatin unfit, PD-L1+) and platinum-refractory urothelial carcinoma (UC). Still, most patients experience progressive disease (PD) as the best response. Although higher response rates to subsequent systemic treatment (SST) have been described, post-PD outcome data are scarce.

OBJECTIVE

To examine the outcome of UC patients who received SST and no SST after progressing to ICIs.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis of UC patients progressing to frontline or later-line anti-PD-1/PD-L1 therapy in 10 European institutions was conducted between March 2013 and September 2017.

INTERVENTION

Post-PD management as per standard practice.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Overall survival (OS) was analyzed with a Kaplan-Meier model. Cox regression was used for multivariate analysis (MV). Impact of SST on OS was examined with a time-varying covariate model.

RESULTS AND LIMITATIONS

A total of 270 UC patients with PD to ICIs (69 frontline, 201 later line) were analyzed. Of the patients, 57% of frontline-ICI-PD and 34% of later-line-ICI-PD patients received SST, and SST had an impact on OS in MV (frontline: hazard ratio [HR] 0.22, 95% confidence interval [CI] 0.10-0.51, p <  0.001; later line: HR 0.22, 95% CI 0.13-0.36, p <  0.001). In the frontline-ICI-PD group, median OS with and without SST was 6.8 mo (95% CI 5.0-8.6) and 1.9 mo (95% CI 0.9-3.0), respectively. High disease burden (three or more metastatic sites: HR 2.49, p =  0.03; simultaneous liver/bone metastases: HR 3.93, p =  0.03) predicted worse survival. In later-line-ICI-PD group, response to ICIs (HR 0.37, p =  0.03), longer exposure to ICIs (HR 0.89, p =  0.002), and bone metastasis (HR 2.42, p <  0.001) predicted survival. The retrospective nature of this study and a lack of certain parameters limit the interpretation of our analysis.

CONCLUSIONS

Patients progressing to frontline ICIs are at risk of early death, excluding them from experiencing potential benefit from chemotherapy PATIENT SUMMARY: Our analysis suggests that outcomes after failing immunotherapy are poor, particularly in UC patients who received no prior chemotherapy.