Early efficacy results from atezolizumab (ATZ) with split doses of cisplatin plus gemcitabine in patients with locally advanced or metastatic urothelial carcinoma (SOGUG-AUREA)

502

Background: Urothelial carcinoma (UC) commonly affects patients (pts) who are ineligible for full doses of cisplatin-based chemotherapy (CT) due to bad performance status, advanced age, or renal impairment. The combination of split-dose cisplatin with ATZ might be a feasible treatment for pts with UC who are unfit for full doses of cisplatin. Methods: The phase II SOGUG-AUREA clinical trial recruited treatment-naive pts in advanced or metastatic settings considered unfit for full dose of platinum-based CT. Pts received a split dose of cisplatin (35 mg/m2) and gemcitabine (1000 mg/m2) days 1 and 8 (up to 6 cycles) in combination with 3-weekly ATZ 1200 mg in D1 intravenously until progression, unacceptable toxicity, or absence of clinical benefit. Here we present the early results from the confirmed objective response rate (ORR) according to RECIST 1.1, the primary endpoint for efficacy, progression-free survival (PFS), overall survival (OS) and safety. Results: Between Jan 2021 and Mar 2022, 82 pts were screened, 66 pts were enrolled and received at least one dose of study treatment. Baseline characteristics are outlined in the table. The median duration of ATZ treatment was 4.4 months (m) (95%CI: 4.1-4.6). The confirmed ORR was 40.9%, with 5 (7.6%) pts having CR and 22 (33.3%) PR. The median duration of the response was 7 m (95%CI: 4.9-10.4). The clinical benefit rate (CBR) was 53%, and SD (maintained > 6m) was reported in 8 (12.1%) pts. Eight (12.1%) pts were not evaluable for response due to exitus previous to disease evaluation (9.1%), non measurable target lesions (1.5%) or withdrawal (1.5%). With a median follow-up of 9.3 m (range: 0.6-18.1), the median PFS was 6.9 m (95%CI: 6.4-9.2), with a 6-m PFS rate of 67.1% (95% CI: 56.5-79.7). The reasons for platinum ineligibility did not correlate with PFS. The 6-m OS rate was 78.2% (95%CI: 68.6-89). Most frequent grade 3-4 toxicities were neutrophil count decreased (24.2%), anemia (21.5%) and platelet count decreased (13.6%). Conclusions: ATZ with split doses of CT was safely administered in a population of frail pts with mUC who were unfit for CT showing promising preliminary survival outcomes in terms of response. Final survival results are awaited. Clinical trial information: NCT04602078 . [Table: see text]

Long-term Clinical Outcomes of a Spanish Cohort of Metastatic Renal Cell Carcinoma Patients with a Complete Response to Sunitinib

INTRODUCTION

The long-term clinical outcomes of patients with metastatic renal cell carcinoma (mRCC) and a complete response (CR) to the tyrosine kinase inhibitor (TKI) sunitinib are poorly known. The characteristics of these patients could reveal previously undetected associations with clinical variables.

PATIENTS AND METHODS

This observational, retrospective study (ATILA) used data from a registry of patients with mRCC who had received first-line sunitinib and had achieved CR from 2007 to 2018 in Spain.

RESULTS

Sixty-two patients with CR were included; 48 patients (77.4%) received sunitinib in monotherapy and 14 (22.6%) combined with or followed by local treatment. Median age was 58.5 years (range, 32-81). Most patients (79.0%) had clear cell histology and had undergone previous nephrectomy (90.3%). The majority (70.2%) had an intermediate IMDC prognosis, 23% favorable and 7.0% poor. The median time on treatment with sunitinib was 28.2 months (IQR, 16.7-41.0) and the median time to CR was 10.9 months (IQR, 7.2-19.3). After a median follow-up of 8 years (range, 3-13 years), the median PFS was not reached. The overall median duration of complete response was 64.1 months (IQR, 32.2-99.4). The tolerance and safety profile of sunitinib was consistent with previous reports.

CONCLUSION

Durable CR to sunitinib was observed in patients regardless the prognosis group, metastasis site or histology type, with 75% of patients remaining in CR after 10 years.

CLINICALTRIALS

gov: NCT03916458.

AUREA study: Atezolizumab (Atezo) combined with split-dose gemcitabine plus cisplatin (s-GC) in locally advanced or metastatic urothelial cancer (LA/mUC): A SOGUG study

TPS4589

Background: First-line cisplatin-based chemotherapy (70 mg/m2) is the standard of care for LA/mUC patients (pts). However, about 50% will be ineligible for Cisplatin according to Galsky´s criteria. Moreover, a significant proportion of cisplatin-fit pts will receive carboplatin based on physician criteria. s-GC represents a feasible alternative in such situations, and could improve response rate compared to carboplatin regimens. Atezo is a programmed death-ligand 1 (PD-L1) inhibitor that is approved as first line treatment for cisplatin-ineligible LA/mUC pts with PD-L1 expression ≥5% (Ventana SP142). We present the study design of a phase II single arm trial of Atezo +s-GC in previously untreated pts with LA/mUC (NCT04602078). Methods: This single arm, open-label, multicenter study evaluates the efficacy and safety of Atezo +s-GC in previously untreated pts with LA/mUC. 66 pts will be enrolled and receive s-GC x 6 cycles (Cisplatin 35mg/m2 + Gemcitabine 1000mg/m2 on days 1 and 8 Q3W) and Atezo (1200 mg IV Q3W), followed by Atezo (1200 mg IV Q3W) until disease progression, toxicity or absence of clinical benefit. Eligibility criteria include histologically confirmed unresectable LA/mUC, measurable disease per RECIST 1.1 and adequate organ and marrow. Pts must be unfit for full cisplatin dose based on: age > 70 years, PS ECOG 0-2, creatinine Clearance >30 and <60 mL/min per Cockroft-Gault formula or by 24-hour urine collection. Other reasons for cisplatin ineligibility as considered by investigator, including those uncovered by Galsky´s criteria, will be allowed, prior discussion with PI. Exclusion criteria include prior systemic therapy for LA/mUC (adjuvant/neoadjuvant allowed if finished > 12 months prior to inclusion), prior autoimmune disease and uncontrolled significant illnesses. The primary endpoint is ORR per RECIST 1.1 assessed by investigator; the secondary endpoints are DoR, OS, PFS and safety. Biomarker analysis, including PD-L1 expression and microbiome relationship, will be an exploratory objective. The first two patients were enrolled in February 2021. Clinical trial information: NCT04602078.

PROREPAIR-B: A Prospective Cohort Study of the Impact of Germline DNA Repair Mutations on the Outcomes of Patients With Metastatic Castration-Resistant Prostate Cancer

PURPOSE

Germline mutations in DNA damage repair (DDR) genes are identified in a significant proportion of patients with metastatic prostate cancer, but the clinical implications of these genes remain unclear. This prospective multicenter cohort study evaluated the prevalence and effect of germline DDR (gDDR) mutations on metastatic castration-resistance prostate cancer (mCRPC) outcomes.

PATIENTS AND METHODS

Unselected patients were enrolled at diagnosis of mCRPC and were screened for gDDR mutations in 107 genes. The primary aim was to assess the impact of ATM/BRCA1/BRCA2/ PALB2 germline mutations on cause-specific survival (CSS) from diagnosis of mCRPC. Secondary aims included the association of gDDR subgroups with response outcomes for mCRPC treatments. Combined progression-free survival from the first systemic therapy (PFS) until progression on the second systemic therapy (PFS2) was also explored.

RESULTS

We identified 68 carriers (16.2%) of 419 eligible patients, including 14 with BRCA2, eight with ATM, four with BRCA1, and none with PALB2 mutations. The study did not reach its primary end point, because the difference in CSS between ATM/BRCA1/BRCA2/PALB2 carriers and noncarriers was not statistically significant (23.3 v 33.2 months; P = .264). CSS was halved in germline BRCA2 (g BRCA2) carriers (17.4 v 33.2 months; P = .027), and g BRCA2 mutations were identified as an independent prognostic factor for CCS (hazard ratio [HR], 2.11; P = .033). Significant interactions between g BRCA2 status and treatment type (androgen signaling inhibitor v taxane therapy) were observed (CSS adjusted P = .014; PFS2 adjusted P = .005). CSS (24.0 v 17.0 months) and PFS2 (18.9 v 8.6 months) were greater in g BRCA2 carriers treated in first line with abiraterone or enzalutamide compared with taxanes. Clinical outcomes did not differ by treatment type in noncarriers.

CONCLUSION

g BRCA2 mutations have a deleterious impact on mCRPC outcomes that may be affected by the first line of treatment used. Determination of g BRCA2 status may be of assistance for the selection of the initial treatment in mCRPC. Nonetheless, confirmatory studies are required before these results can support a change in clinical practice.

Functional PTGS2 polymorphism-based models as novel predictive markers in metastatic renal cell carcinoma patients receiving first-line sunitinib

Sunitinib is the currently standard treatment for metastatic renal cell carcinoma (mRCC). Multiple candidate predictive biomarkers for sunitinib response have been evaluated but none of them has been implemented in the clinic yet. The aim of this study was to analyze single nucleotide polymorphisms (SNPs) in genes linked to mode of action of sunitinib and immune response as biomarkers for mRCC. This is a multicenter, prospective and observational study involving 20 hospitals. Seventy-five mRCC patients treated with sunitinib as first line were used to assess the impact of 63 SNPs in 31 candidate genes on clinical outcome. rs2243250 (IL4) and rs5275 (PTGS2) were found to be significantly associated with shorter cancer-specific survival (CSS). Moreover, allele C (rs5275) was associated with higher PTGS2 expression level confirming its functional role. Combination of rs5275 and rs7651265 or rs2243250 for progression free survival (PFS) or CSS, respectively, was a more valuable predictive biomarker remaining significant after correction for multiple testing. It is the first time that association of rs5275 with survival in mRCC patients is described. Two-SNP models containing this functional variant may serve as more predictive biomarkers for sunitinib and could suppose a clinically relevant tool to improve the mRCC patient management.

Cost analysis of skeletal-related events in Spanish patients with bone metastases from solid tumours

PURPOSE

To estimate the cost per skeletal-related event (SRE) in patients with bone metastases secondary to solid tumours in the Spanish healthcare setting.

METHODS

Patients diagnosed with bone metastases secondary to breast, prostate or lung cancer were included in this multicentre, observational study. SREs are defined as pathologic fracture (vertebral and non-vertebral fracture), radiation to bone, spinal cord compression or surgery to bone. Health resource utilisation associated with these events (inpatient stays, outpatient, emergency room and home health visits, nursing home stays and procedures) were collected retrospectively for all SREs that occurred in the 97 days prior to enrolment and prospectively during follow-up. Unit costs were obtained from the 2010 eSalud healthcare costs database.

RESULTS

A total of 93 Spanish patients with solid tumours were included (31 had breast cancer, 21 prostate cancer and 41 lung cancer), contributing a total of 143 SREs to this cost analysis. Inpatient stays (between 9.0 and 29.9 days of mean length of stay per inpatient stay by SRE type) and outpatient visits (between 1.7 and 6.4 mean visits per SRE type) were the most frequently reported types of health resources utilised. The mean cost per SRE was between <euro>2,377.79 (radiation to bone) and <euro>7,902.62 (spinal cord compression).

CONCLUSION

SREs are associated with a significant consumption of healthcare resources that generate a substantial economic burden for the Spanish healthcare system.