Final Results From a Phase I Trial and Expansion Cohorts of Cabozantinib and Nivolumab Alone or With Ipilimumab for Advanced/Metastatic Genitourinary Tumors.

PURPOSE: Cabozantinib and nivolumab (CaboNivo) alone or with ipilimumab (CaboNivoIpi) have shown promising efficacy and safety in patients with metastatic urothelial carcinoma (mUC), metastatic renal cell carcinoma (mRCC), and rare genitourinary (GU) tumors in a dose-escalation phase I study. We report the final data analysis of the safety, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) of the phase I patients and seven expansion cohorts. METHODS: This is an investigator-initiated, multicenter, phase I trial. CaboNivo doublet expansion cohorts included (1) mUC, (2) mRCC, and (3) adenocarcinoma of the bladder/urachal; CaboNivoIpi triplet expansion cohorts included (1) mUC, (2) mRCC, (3) penile cancer, and (4) squamous cell carcinoma of the bladder and other rare GU tumors (ClinicalTrials.gov identifier: NCT02496208). RESULTS: The study enrolled 120 patients treated with CaboNivo (n = 64) or CaboNivoIpi (n = 56), with a median follow-up of 49.2 months. In 108 evaluable patients (CaboNivo n = 59; CaboNivoIpi n = 49), the ORR was 38% (complete response rate 11%) and the median duration of response was 20 months. The ORR was 42.4% for mUC, 62.5% for mRCC (n = 16), 85.7% for squamous cell carcinoma of the bladder (n = 7), 44.4% for penile cancer (n = 9), and 50.0% for renal medullary carcinoma (n = 2). Grade ≥ 3 treatment-related adverse events occurred in 84% of CaboNivo patients and 80% of CaboNivoIpi patients. CONCLUSION: CaboNivo and CaboNivoIpi demonstrated clinical activity and safety in patients with multiple GU malignancies, especially clear cell RCC, urothelial carcinoma, and rare GU tumors such as squamous cell carcinoma of the bladder, small cell carcinoma of the bladder, adenocarcinoma of the bladder, renal medullary carcinoma, and penile cancer.

Cabozantinib plus Nivolumab Phase I Expansion Study in Patients with Metastatic Urothelial Carcinoma Refractory to Immune Checkpoint Inhibitor Therapy.

PURPOSE: This study investigated the efficacy and tolerability of cabozantinib plus nivolumab (CaboNivo) in patients with metastatic urothelial carcinoma (mUC) that progressed on checkpoint inhibition (CPI). PATIENTS AND METHODS: A phase I expansion cohort of patients with mUC who received prior CPI was treated with cabozantinib 40 mg/day and nivolumab 3 mg/kg every 2 weeks until disease progression/unacceptable toxicity. The primary goal was objective response rate (ORR) per RECIST v.1.1. Secondary objectives included progression-free survival (PFS), duration of response (DoR), overall survival (OS), safety, and tolerability. RESULTS: Twenty-nine out of 30 patients enrolled were evaluable for efficacy. Median follow-up was 22.2 months. Most patients (86.7%) received prior chemotherapy and all patients received prior CPI (median seven cycles). ORR was 16.0%, with one complete response and three partial responses (PR). Among 4 responders, 2 were primary refractory, 1 had a PR, and 1 had stable disease on prior CPI. Median DoR was 33.5 months [95% confidence interval (CI), 3.7-33.5], median PFS was 3.6 months (95% CI, 2.1-5.5), and median OS was 10.4 months (95% CI, 5.8-19.5). CaboNivo decreased immunosuppressive subsets such as regulatory T cells (Tregs) and increased potential antitumor immune subsets such as nonclassical monocytes and effector T cells. A lower percentage of monocytic myeloid-derived suppressor cells (M-MDSC) and polymorphonuclear MDSCs, lower CTLA-4 and TIM-3 expression on Tregs, and higher effector CD4+ T cells at baseline were associated with better PFS and/or OS. CONCLUSIONS: CaboNivo was clinically active, well tolerated, and favorably modulated peripheral blood immune subsets in patients with mUC refractory to CPI.

Circulating Tumor Cell Subtypes and T-cell Populations as Prognostic Biomarkers to Combination Immunotherapy in Patients with Metastatic Genitourinary Cancer.

PURPOSE: Circulating tumor cells (CTC) are under investigation as a minimally invasive liquid biopsy that may improve risk stratification and treatment selection. CTCs uniquely allow for digital pathology of individual malignant cell morphology and marker expression. We compared CTC features and T-cell counts with survival endpoints in a cohort of patients with metastatic genitourinary cancer treated with combination immunotherapy. EXPERIMENTAL DESIGN: Markers evaluated included pan-CK/CD45/PD-L1/DAPI for CTCs and CD4/CD8/Ki-67/DAPI for T cells. ANOVA was used to compare CTC burden and T-cell populations across timepoints. Differences in survival and disease progression were evaluated using the maximum log-rank test. RESULTS: From December 2016 to January 2019, 183 samples from 81 patients were tested. CTCs were found in 75% of patients at baseline. CTC burden was associated with shorter overall survival (OS) at baseline (P = 0.022), but not on-therapy. Five morphologic subtypes were detected, and the presence of two specific subtypes with unique cellular features at baseline and on-therapy was associated with worse OS (0.9-2.3 vs. 28.2 months; P < 0.0001-0.013). Increasing CTC heterogeneity on-therapy had a trend toward worse OS (P = 0.045). PD-L1+ CTCs on-therapy were associated with worse OS (P < 0.01, cycle 2). Low baseline and on-therapy CD4/CD8 counts were also associated with poor OS and response category. CONCLUSIONS: Shorter survival may be associated with high CTC counts at baseline, presence of specific CTC morphologic subtypes, PD-L1+ CTCs, and low %CD4/8 T cells in patients with metastatic genitourinary cancer. A future study is warranted to validate the prognostic utility of CTC heterogeneity and detection of specific CTC morphologies.

Phase I Study of Cabozantinib and Nivolumab Alone or With Ipilimumab for Advanced or Metastatic Urothelial Carcinoma and Other Genitourinary Tumors.

PURPOSE: We assessed the safety and efficacy of cabozantinib and nivolumab (CaboNivo) and CaboNivo plus ipilimumab (CaboNivoIpi) in patients with metastatic urothelial carcinoma (mUC) and other genitourinary (GU) malignances. PATIENTS AND METHODS: Patients received escalating doses of CaboNivo or CaboNivoIpi. The primary objective was to establish a recommended phase II dose (RP2D). Secondary objectives included objective response rate (ORR), progression-free survival (PFS), duration of response (DoR), and overall survival (OS). RESULTS: Fifty-four patients were enrolled at eight dose levels with a median follow-up time of 44.6 months; data cutoff was January 20, 2020. Grade 3 or 4 treatment-related adverse events (AEs) occurred in 75% and 87% of patients treated with CaboNivo and CaboNivoIpi, respectively, and included fatigue (17% and 10%, respectively), diarrhea (4% and 7%, respectively), and hypertension (21% and 10%, respectively); grade 3 or 4 immune-related AEs included hepatitis (0% and 13%, respectively) and colitis (0% and 7%, respectively). The RP2D was cabozantinib 40 mg/d plus nivolumab 3 mg/kg for CaboNivo and cabozantinib 40 mg/d, nivolumab 3 mg/kg, and ipilimumab 1 mg/kg for CaboNivoIpi. ORR was 30.6% (95% CI, 20.0% to 47.5%) for all patients and 38.5% (95% CI, 13.9% to 68.4%) for patients with mUC. Median DoR was 21.0 months (95% CI, 5.4 to 24.1 months) for all patients and not reached for patients with mUC. Median PFS was 5.1 months (95% CI, 3.5 to 6.9 months) for all patients and 12.8 months (95% CI, 1.8 to 24.1 months) for patients with mUC. Median OS was 12.6 months (95% CI, 6.9 to 18.8 months) for all patients and 25.4 months (95% CI, 5.7 to 41.6 months) for patients with mUC. CONCLUSION: CaboNivo and CaboNivoIpi demonstrated manageable toxicities with durable responses and encouraging survival in patients with mUC and other GU tumors. Multiple phase II and III trials are ongoing for these combinations.

Circulating microRNA profile predicts disease progression in patients receiving second-line treatment of lapatinib and capecitabine for metastatic pancreatic cancer.

Patients exhibiting pancreatic cancer possess poor rates of survival. Therefore, the identification of a biomarker that can be measured non-invasively and be used to predict patient outcomes is required for the successful treatment of pancreatic cancer. The present study evaluated serum microRNA (miRNA/miR) profiles in patients exhibiting pancreatic cancer, who were treated with lapatinib and capecitabine in a phase II trial. Serum samples were collected for the measurement of a panel of miRNAs (miR-21, miR-210, miR-221 and miR-7) associated with the epidermal growth factor receptor (EGFR)1 and human epidermal growth factor receptor (HER)2 pathways. Preclinically, human pancreatic cancer PANC-1, MIA PaCa-2 and BXCP-3 cell lines were utilized for miRNA and drug resistance studies. In total, 6/17 patients treated experienced disease progression following 2 cycles of treatment [non-responders (NRS)], while another 6/17 patients exhibited a stable disease state and received >4 cycles of treatment [responders (RS); range, 4-22 cycles]. Five patients withdrew from the study due to severe toxicity or mortality. The mean overall survival time was 6.5 vs. 10.4 months for NRS and RS, respectively. Significant upregulation of serum miRNAs at earlier time points (3-6 weeks) was observed in NRS. miRNA levels increased with cancer progression, and lapatinib and 5-fluorouracil (5-FU; the active form of capecitabine) treatment increased the miRNA levels (specifically miR-210 and miR-221) in the treatment-resistant pancreatic cancer PANC-1 and MIA PaCa-2 cell lines. However, lapatinib and 5-FU treatment did not increase the miRNA levels in the treatment-sensitive BXPC-3 cell line. Inhibition of miR-221 increased the sensitivity of the PANC-1 cells to treatment. In conclusion, an increase in specific serum miRNAs was associated with resistance to lapatinib and capecitabine treatment. Additional investigation is required with regard to the application of the miRNA panel investigated in the present study as a potential predictor of patient responses to anti-EGFR/HER2 treatment.

Phase II study of lapatinib and capecitabine in second-line treatment for metastatic pancreatic cancer.

PURPOSE: Patients with metastatic, gemcitabine-refractory pancreatic cancer typically have poor survival. Erlotinib, a targeted therapy that inhibits epidermal growth factor receptor (EGFR) activity (overexpressed in 40-60 % of pancreatic cancers), was FDA approved for the treatment of patients with advanced pancreatic cancer. Human epidermal growth factor receptor 2 (HER-2), another member of the ErbB family of growth factor receptor tyrosine kinases, has also been a therapeutic target of interest in pancreatic cancer; HER-2 overexpression is found in 20 % of pancreatic cancers. Lapatinib is a tyrosine kinase inhibitor that binds to both EGFR and HER-2. We conducted a single-arm phase II study to evaluate the combination of lapatinib and capecitabine in the second-line treatment of metastatic, gemcitabine-refractory pancreatic cancer. METHODS: Seventeen patients with metastatic, unresectable pancreatic cancer whose disease had progressed on first-line gemcitabine-based therapy were selected for this study. Patients were required to have an adequate performance status (ECOG 0-2) and normal hepatic and renal function prior to being enrolled. Patients received lapatinib 1250 mg PO daily 1 h before or after meals, and capecitabine 1000 mg/m(2) PO twice daily on days 1-14 of the 21-day cycle. The primary endpoint was median overall survival (OS), and the secondary endpoints were objective response rate, progression-free survival (PFS) and the safety profile of the combination therapy. Clinical toxicities were assessed according to the National Cancer Institute Common Toxicity Criteria for Adverse Events version 4.0. Radiographic response was evaluated by RECIST criteria. RESULTS: Clinically, six of the 17 patients treated had disease progression (PD) after two cycles, six of 17 patients had stable disease (SD) and received more than four cycles (SD, range 4-22 cycles). For all patients, median PFS was 2.6 months (95 % CI 1.3-3.8) and median OS was 5.2 months (95 % CI 3.4-9). Treatment-related toxicities were limited to three (17 %) patients developing grade 3 adverse events such as nausea, vomiting, diarrhea and fatigue. When stratifying patients by treatment response, we found a statistically significant difference in median PFS and OS: median PFS was 1.4 months (95 % CI 1.0-1.8) in the PD group versus 4.0 months (95 % CI 1.8-6.3) in the SD group (P value = 0.001). Median OS was 2.9 months (95 % CI 0-7.3) in the PD group versus 8.3 months (95 % CI 0-21.2) in the SD group (P value = 0.023). CONCLUSIONS: The combination of lapatinib and capecitabine is a tolerable regimen for patients with gemcitabine-refractory pancreatic cancer; however, this observation is based on the small number of patients enrolled in the trial. A subset of the enrolled patients had clinical benefit from treatment. Predictive biomarkers that allow selection of patients that will respond to this regimen should be further investigated.

Human Pancreatic Cancer-Associated Stellate Cells Remain Activated after in vivo Chemoradiation.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by an extensive fibrotic reaction or desmoplasia and complex involvement of the surrounding tumor microenvironment. Pancreatic stellate cells are a key mediator of the pancreatic matrix and they promote progression and invasion of pancreatic cancer by increasing cell proliferation and offering protection against therapeutic interventions. Our study utilizes human tumor-derived pancreatic stellate cells (HTPSCs) isolated from fine needle aspirates of pancreatic cancer tissue from patients with locally advanced, unresectable pancreatic adenocarcinoma before and after treatment with full-dose gemcitabine plus concurrent hypo-fractionated stereotactic radiosurgery. We show that HTPSCs survive in vivo chemotherapy and radiotherapy treatment and display a more activated phenotype post-therapy. These data support the idea that stellate cells play an essential role in supporting and promoting pancreatic cancer and further research is needed to develop novel treatments targeting the pancreatic tumor microenvironment.

Stereotactic body radiation therapy with concurrent full-dose gemcitabine for locally advanced pancreatic cancer: a pilot trial demonstrating safety.

BACKGROUND: Concurrent chemoradiation is a standard option for locally advanced pancreatic cancer (LAPC). Concurrent conventional radiation with full-dose gemcitabine has significant toxicity. Stereotactic body radiation therapy (SBRT) may provide the opportunity to administer radiation in a shorter time frame with similar efficacy and reduced toxicity. This Pilot study assessed the safety of concurrent full-dose gemcitabine with SBRT for LAPC. METHODS: Patients received gemcitabine, 1000 mg/m2 for 6 cycles. During week 4 of cycle 1, patients received SBRT (25 Gy delivered in five consecutive daily fractions of 5 Gy prescribed to the 75-83% isodose line). Acute and late toxicities were assessed using NIH CTCAE v3. Tumor response was assessed by RECIST. Patients underwent an esophagogastroduodenoscopy at baseline, 2, and 6 months to assess the duodenal mucosa. Quality of life (QoL) data was collected before and after treatment using the QLQ-C30 and QLQ-PAN26 questionnaires. RESULTS: Between September 2009 and February 2011, 11 patients enrolled with one withdrawal during radiation therapy. Patients had grade 1 to 2 gastrointestinal toxicity from the start of SBRT to 2 weeks after treatment. There were no grade 3 or greater radiation-related toxicities or delays for cycle 2 of gemcitabine. On endoscopy, there were no grade 2 or higher mucosal toxicities. Two patients had a partial response. The median progression free and overall survival were 6.8 and 12.2 months, respectively. Global QoL did not change between baseline and immediately after radiation treatment. CONCLUSIONS: SBRT with concurrent full dose gemcitabine is safe when administered to patients with LAPC. There is no delay in administration of radiation or chemotherapy, and radiation is completed with minimal toxicity.