A Pilot Study of F-18 Fluciclovine-PET/CT as a Diagnostic Tool for Bone Metastases in Patients With Castrate Resistant Prostate Adenocarcinoma and Correlative Analysis of Blood and Bone Molecular Testing (The FACT Study).

BACKGROUND: Suspicious F-18 fluciclovine PET/CT findings for osseous metastases from prostate cancer (PC) were targeted for core needle biopsy. We correlated the maximum standardized uptake value (SUVmax) of biopsied lesions, with biopsy results, other diagnostic outcomes, and blood and tissue molecular analysis (TMA). MATERIAL AND METHODS: Patients with castrate resistant prostate cancer (CRPC) were recruited from a university oncology clinic. SUVmax, histology, blood, and TMA were correlated. RESULTS: Fifteen patients were enrolled and 12 underwent bone biopsies. Fifty percent of bone biopsies demonstrated malignancy. Higher SUVmax was associated with positive biopsies for adenocarcinoma (P = .003), and lesions with SUVmax ≥ 5.1 were all positive for malignancy. Significant correlation between blood and somatic TMA (P = .002) was also found. CONCLUSION: Higher uptake of F-18 fluciclovine was associated with higher predictive value for osseous metastasis on biopsy. There was a significant correlation between blood and TMA.

A drug safety evaluation of pemigatinib for advanced cholangiocarcinoma.

INTRODUCTION: Pemigatinib is a selective small-molecule inhibitor of the fibroblast growth factor receptor (FGFR) 1-3. FGFR is associated with increased cell division, proliferation, and survival. Inhibition of this receptor is an effective treatment against tumors driven by activated fusions in FGFR2. AREAS COVERED: The drug was first evaluated in patients with advanced solid tumors and demonstrated a manageable safety profile, with the most common adverse events being oscillations in blood phosphate levels, fatigue, gastrointestinal symptoms, and skin and ocular toxicities. Pemigatinib was further evaluated in a phase II cohort study of patients with previously treated locally advanced or metastatic cholangiocarcinoma harboring FGFR2 genomic alterations. After a median follow-up of 17.8 months, the objective response rate in patients with tumors harboring FGFR2 fusions or rearrangements was 35.5% (95% CI, 26.5-45.4). Based on these results, the FDA granted accelerated approval on 17 April 2020, to pemigatinib, for the treatment of adults with previously treated, unresectable locally advanced or metastatic cholangiocarcinoma with an FGFR2 fusion or another rearrangement. Articles selected for this review were based on reported studies indexed in PubMed (2010-2023). EXPERT OPINION: Future perspectives in the treatment of FGFR2 fused cholangiocarcinoma include the evaluation of pemigatinib in previously untreated patients and possible active combinations or sequencing strategies with other drugs.

An Excellent Response of Microsatellite Instability-High Pancreatic Adenocarcinoma to Pembrolizumab Treatment: The Role of Circulating Tumor DNA Testing.

The role of circulating tumor DNA (ctDNA) is expanding in oncology practices, and it is increasingly being used for targeted therapies and disease monitoring. It is minimally invasive and provides data from both primary and secondary sites of disease. Herein, we report a unique case of a patient with microsatellite instability-high (MSI-H) pancreatic adenocarcinoma (PDAC) treated with neoadjuvant chemotherapy and pembrolizumab who achieved a pathologically confirmed complete resolution of the tumor. A 75-year-old female was diagnosed with pancreatic adenocarcinoma (PDAC) in the uncinate process with aortocaval and retrocrural adenopathy. Next-generation sequencing was obtained via ctDNA testing, and the patient was initiated on cytotoxic chemotherapy while awaiting results. ctDNA revealed MSI-H status, and pembrolizumab was added to the cytotoxic chemotherapy regimen. At follow-up after five cycles of treatment, excellent treatment response was noted on magnetic resonance imaging (MRI) of the abdomen, demonstrating the resolution of the pancreatic mass and adenopathy. Six months of neoadjuvant treatment was given in total, after which the patient underwent resection with curative intent and achieved a complete pathological response with no evidence of disease. The role of ctDNA testing in directing treatment and influencing follow-up has already demonstrated great value. In our case, ctDNA adequately replaced conventional tissue biopsy, alleviating the burden of invasive testing on the patient. This is of great value, especially for patients with non-resectable tumors as well as in several other clinical scenarios. Our case also contributes to the growing body of literature demonstrating the role of immune-directed therapy for MSI-H PDAC.

Targeting leukemia inhibitory factor in pancreatic adenocarcinoma.

INTRODUCTION: The Leukemia Inhibitory Factor (LIF) is a member of the interleukin-6 (IL-6) cytokine family. Known to induce differentiation of myeloid leukemia cells, evidence has accumulated supporting its role in cancer evolution through regulating cell differentiation, renewal, and survival. LIF has recently emerged as a biomarker and therapeutic target for pancreatic ductal adenocarcinoma (PDAC). The first in-human clinical trial has shown promising safety profile and has suggested a potential role for LIF inhibitor in combination regimen. AREAS COVERED: Herein, we summarize, discuss, and give an expert opinion on the role of LIF in PDAC promotion, and its potential role as a biomarker and target of anti-cancer therapy. We conducted an exhaustive PubMed search for English-language articles published from 1 January 1970, to 1 August 2022. EXPERT OPINION: PDAC carries a devastating prognosis for patients, highlighting the need for advancing drug development. The results of the phase 1 trial with MSC-1 demonstrated tolerability and safety but modest efficacy. Future research should focus on investigating LIF targets in combination with current standard-of-care chemotherapy, and immunotherapy can be a promising approach. Further, larger multicenter clinical trials are needed to define the use of LIF as a new biomarker in PDAC patients.

Proton Therapy With Concurrent Chemotherapy for Thoracic Esophageal Cancer: Toxicity, Disease Control, and Survival Outcomes.

Purpose: When treating esophageal cancer with radiation therapy, it is critical to limit the dose to surrounding structures, such as the lung and/or heart, as much as possible. Proton radiation therapy allows a reduced radiation dose to both the heart and lungs, potentially reducing the risk of cardiopulmonary toxicity. Here, we report disease control, survival, and toxicity outcomes among patients with esophageal cancer treated with proton radiation therapy and concurrent chemotherapy (chemoradiation therapy; CRT) with or without surgery. Materials and Methods: We enrolled 17 patients with thoracic esophageal carcinoma on a prospective registry between 2010 and 2021. Patients received proton therapy to a median dose of 50.4-GyRBE (range, 50.4-64.8) in 1.8-Gy fractions.Acute and late toxicities were graded per the Common Terminology Criteria for Adverse Events, version 4.0 (US National Cancer Institute, Bethesda, Maryland). In addition, disease control, patterns of failure, and survival outcomes were collected. Results: Nine patients received preoperative CRT, and 8 received definitive CRT. Overall, 88% of patients had adenocarcinoma, and 12% had squamous cell carcinoma. With a median follow-up of 2.1 years (range, 0.5-9.4), the 3-year local progression-free, disease-free, and overall survival rates were 85%, 66%, and 55%, respectively. Two patients (1 with adenocarcinoma and 1 with squamous cell carcinoma) recurred at the primary site after refusing surgery after a complete clinical response to CRT. The most common acute nonhematologic and hematologic toxicities, respectively, were grades 1 to 3 esophagitis and grades 1 to 4 leukopenia, both affecting 82% of patients. No acute cardiopulmonary toxicities were observed in the absence of surgical resection. Reagarding surgical complications, 3 postoperative cardiopulmonary complications occurred as follows: 1 grade 1 pleural effusion, 1 grade 3 pleural effusion, and 1 grade 2 anastomotic leak. Two severe late CRT toxicities occurred: 1 grade 5 tracheoesophageal fistula and 1 grade 3 esophageal stenosis requiring a feeding tube. Conclusion: Proton radiation therapy is a safe, effective treatment for esophageal cancer with increasing evidence supporting its role in reducing cardiopulmonary toxicity.

Novel precision therapies for cholangiocarcinoma: an overview of clinical trials.

INTRODUCTION: The treatment landscape of biliary cancers is rapidly changing. Inhibitors against the actionable targets FGFR and IDH1 are now being included in the treatment guidelines of multiple countries for patients with advanced cholangiocarcinoma. However, there remains an unmet need in identifying the mechanisms of resistance and treatment strategies involving possible tumor sequencing. AREAS COVERED: In this review article, we address clinical trials evaluating FGFR, IDH, BRAF and HER2 inhibitors in advanced cholangiocarcinoma. We also review the mechanisms of resistance described thus far and approaches to overcome them. Articles selected for this review were based on reported studies indexed in PubMed (2010-2022). EXPERT OPINION: Precision medicine in biliary cancers has already been incorporated into the treatment landscape of the disease in many countries. Fusions of FGFR2 and mutations in IDH1 are the first drivers with targetable treatments approved in these cancers. HER2 and BRAF would be the next drivers with possible tumor-agnostic or cholangiocarcinoma-specific approvals. The advent of ctDNA could improve the accessibility of sequencing and recruitment in these clinical trials. However, limitations of detecting fusions should be considered and addressed in these platforms.

Genomic landscape of advanced prostate cancer patients with BRCA1 versus BRCA2 mutations as detected by comprehensive genomic profiling of cell-free DNA.

BRCA1-mutated prostate cancer has been shown to be less responsive to poly (ADP-ribose) polymerase (PARP) inhibitors as compared to BRCA2-mutated prostate cancer. The reason for this differential response is not clear. We hypothesized this differential sensitivity to PARP inhibitors may be explained by distinct genomic landscapes of BRCA1 versus BRCA2 co-segregating genes. In a large dataset of 7,707 men with advanced prostate cancer undergoing comprehensive genomic profiling (CGP) of cell-free DNA (cfDNA), 614 men harbored BRCA1 and/or BRCA2 alterations. Differences in the genomic landscape of co-segregating genes was investigated by Fisher's exact test and probabilistic graphical models (PGMs). Results demonstrated that BRCA1 was significantly associated with six other genes, while BRCA2 was not significantly associated with any gene. These findings suggest BRCA2 may be the main driver mutation, while BRCA1 mutations tend to co-segregate with mutations in other molecular pathways contributing to prostate cancer progression. These hypothesis-generating data may explain the differential response to PARP inhibition and guide towards the development of combinatorial drug regimens in those with BRCA1 mutation.

Exceptional response to cyclophosphamide and dexamethasone in a patient with metastatic castrate-resistant prostate cancer and RB1 mutation.

Rates of prostate cancer relapsing from anti-androgen therapies are increasing in the United States and worldwide. It has been suggested that this is caused by variant and altered lineage marker expression within the tumor, allowing for lineage plasticity that then facilitates therapeutic resistance. The genomic landscape of castrate-resistant prostate cancer has been well-defined with the advent of next-generation sequencing, but the clinical applications of these findings as measured by patient outcomes remains poorly understood. Here, we report on a patient with recurrent, metastatic castrate-resistant prostate cancer and identified RB1 mutation with progressive symptomatology, who was treated with cyclophosphamide and dexamethasone after other standard treatment regimens failed. After completing 2 years of treatment, he experienced complete resolution of his symptoms. Disease remission was confirmed on multiple imaging modalities and through serial measurements of prostate-specific antigen levels that showed a reduction of 99%. Our patient's case supports ongoing research that genetic profiling can help elucidate key biological and molecular tumor components, which can then inform targeted, individualized treatment approaches in the management of recurrent, castrate-resistant prostate cancer.

Evaluation of Potential Drug-Drug Interaction Risk of Pexidartinib With Substrates of Cytochrome P450 and P-Glycoprotein.

Pexidartinib is approved for treatment of adults with symptomatic tenosynovial giant cell tumor. In vitro data showed pexidartinib's potential to inhibit and induce cytochrome P450 (CYP) 3A, inhibit CYP2C9, CYP2C19 and P-glycoprotein (P-gp). Herein, 2 open-label, single-sequence, crossover studies evaluated the drug-drug interaction potential of pexidartinib on CYP enzymes (CYP2C9, CYP2C19, and CYP3A) and P-gp. Thirty-two subjects received single oral doses of midazolam (CYP3A substrate) and tolbutamide (CYP2C9 substrate) alone and after single and multiple oral doses of pexidartinib. Twenty subjects received single oral doses of omeprazole (CYP2C19 substrate) and digoxin (P-gp substrate) alone or with pexidartinib. Analysis of variance was conducted to determine the effect of pexidartinib on various substrates' pharmacokinetics. No drug-drug interaction was concluded if the 90% confidence interval of the ratio of test to reference was within the range 80% to 125%. Coadministration of single and multiple doses of pexidartinib resulted in 21% and 52% decreases, respectively, in the area under the plasma concentration-time curve from time zero to the last measurable time point (AUClast ) of midazolam, whereas AUClast values of tolbutamide increased 15% and 36%, respectively. Omeprazole exposure decreased on concurrent administration with pexidartinib, the metabolite-to-parent ratio was similar following omeprazole administration alone vs coadministration with pexidartinib; pexidartinib did not affect CYP2C19-mediated metabolism. Maximum plasma concentrations of digoxin slightly increased (32%) with pexidartinib coadministration; no significant effect on digoxin AUClast . These results indicate that pexidartinib is a moderate inducer of CYP3A and a weak inhibitor of CYP2C9 and does not significantly affect CYP2C19-mediated metabolism or P-gp transport.

Contemporary Management of Pancreatic Cancer from an Internist Perspective.

Primary care physicians are in a favorable position to curb the growing burden of pancreatic ductal adenocarcinoma. This review aims to provide an overview of pancreatic ductal adenocarcinoma from a primary care perspective, with a specific focus on risk factors, selection of high-risk individuals for screening, patient presentation at the primary-care clinic, and the role of the internist in supportive care. Overall, the internist is an essential member of the multidisciplinary care team with respect to optimizing patients' quality of life across various stages of the pancreatic cancer.

Quantitative metric for assessment of pancreatic ductal adenocarcinoma treatment response in T1-weighted gadolinium-enhanced magnetic resonance imaging.

BACKGROUND: We theoretically derived a new quantitative metric reflecting the product of T1 signal intensity and contrast media concentration (T1C) using first principles for the signal provided by the gradient echo sequence. This metric can be used with conventional gadolinium contrast-enhanced magnetic resonance imaging (CE-MRI) exams. We used this metric to test our hypothesis that gadolinium enhancement changes with pancreatic ductal adenocarcinoma (PDA) treatment response, and that this metric may differentiate responders from non-responders. METHODS: Out of 264 initially identified patients, a final total of 35 patients with PDA were included in a retrospective study of responders (n=24) and non-responders (n=11), which used changes in cancer antigen 19-9 (CA 19-9) and tumor size as reference standards. T1C was computed for the pancreatic mass in the arterial, portal venous, and delayed phases in pre-treatment and post-treatment MRIs. Changes in measurements and correlations with treatment response were assessed by repeated measures analysis of variance and paired t-tests. RESULTS: In the treatment responder group, T1C significantly increased in the arterial, portal venous, and delayed phases (P=7.57e-5, P=3.25e-4, P=1.75e-4). In the non-responder group, T1C did not significantly change in any phase (P>0.58). Post-treatment T1C significantly differed between responders and non-responders (P=0.044) by repeated measures analysis of variance. CONCLUSIONS: T1C significantly increases in all phases of CE-MRI in responders to treatment, but does not change in non-responders. T1C correlates with treatment response, can be computed from clinical MRI exams, and may be useful as an additional metric to stratify patients undergoing treatment.

Clinical complexity of utilizing FGFR inhibitors in cancer therapeutics.

INTRODUCTION: Fibroblast growth factor receptors (FGFR 1-4) are a highly conserved family of receptor tyrosine kinases, involved in several physiological processes. Genetic aberrations of FGFRs and their ligands, fibroblast growth factors (FGFs) are involved in several pathological processes including cancer. The FGF-FGFR axis has emerged as a treatment target in oncology. Because these aberrations drive cancer progression, the development of FGFR targeted therapies have been accelerated. AREAS COVERED: In this comprehensive review, we evaluate molecular pathology and targeted therapies to FGFRs. We reviewed the evidence for safety and efficacy from preclinical and clinical studies (phase I-III) of FGFR targeted therapies. We also discuss potential challenges in bringing these targeted therapies from bench to bedside and the potential opportunities. EXPERT OPINION: Despite the challenges of the clinical development of FGFR targeted therapies, two FGFR small-molecule inhibitors, namely Erdafitinib and Pemigatinib, are FDA approved for urothelial cancer and cholangiocarcinoma, respectively. Understanding and detection of FGFR genomic aberrations, protein overexpression and the development of isoform-specific inhibitors are factors in the clinical success of these therapies. An enhanced understanding of patient selection based on a gene signatures or biomarkers is key to success of FGFR targeted therapies.

Rare Tumor-Normal Matched Whole Exome Sequencing Identifies Novel Genomic Pathogenic Germline and Somatic Aberrations.

Whole exome sequencing (WES) of matched tumor-normal pairs in rare tumors has the potential to identify genome-wide mutations and copy number alterations (CNAs). We evaluated 27 rare cancer patients with tumor-normal matching by WES and tumor-only next generation sequencing (NGS) as a comparator. Our goal was to: 1) identify known and novel variants and CNAs in rare cancers with comparison to common cancers; 2) examine differences between germline and somatic variants and how that functionally impacts rare tumors; 3) detect and characterize alleles in biologically relevant genes-pathways that may be of clinical importance but not represented in classical cancer genes. We identified 3343 germline single nucleotide variants (SNVs) and small indel variants-1670 in oncogenes and 1673 in tumor suppressor genes-generating an average of 124 germline variants/case. The number of somatic SNVs and small indels detected in all cases was 523:306 in oncogenes and 217 in tumor suppressor genes. Of the germline variants, six were identified to be pathogenic or likely pathogenic. In the 27 analyzed rare cancer cases, CNAs are variable depending on tumor type, germline pathogenic variants are more common. Cell fate pathway mutations (e.g., Hippo, Notch, Wnt) dominate pathogenesis and double hit (mutation + CNV) represent ~18% cases.

Analyzing outcomes of neoadjuvant and adjuvant treatment for borderline-resectable pancreatic adenocarcinoma in the perioperative period at an academic institution.

BACKGROUND: Only 15-20% of pancreatic ductal adenocarcinoma (PDAC) patients are upfront surgical candidates at presentation, and for this cohort of patients, the 5-year survival is a mere 20% despite adjuvant therapy. Previous data indicate that in clinical practice most of these cases are "borderline-resectable," and there is currently no mature data on perioperative treatment. METHODS: We performed a retrospective electronic chart review of patients with "borderline-resectable"PDAC treated at an academic comprehensive cancer center, dividing them into groups based on surgery alone, surgery plus neoadjuvant, adjuvant, or neoadjuvant plus adjuvant perioperative treatment groups. The objectives were to determine the median overall survival (mOS), progression-free survival (PFS) and disease-free survival (DFS). Statistical analysis was performed to assess the association of demographic, tumor traits, and interventions with OS, PFS and DFS. RESULTS: Only surgery followed by adjuvant therapy showed an increase in mOS [hazard ratio (HR) 0.22; 95% CI, 0.09-0.51; P<0.001), after adjustment for radiation (yes vs. no), resection margins (R0 vs. R1 or R2), and tumor location (head vs. body or tail). Patients who received adjuvant therapy after surgery had 2.1 times greater odds to be alive at 24 months after diagnosis than those who had surgery alone (P=0.015). PFS and DFS were not statistically significantly different among treatment groups after adjustment. Those whose disease was located in the head of the pancreas had a significantly improved OS (HR =0.27; 95% CI, 0.11-0.64; P=0.003), PFS (HR =0.40; 95% CI, 0.17-0.94; P=0.035), and DFS (HR =0.30; 95% CI, 0.13-0.67; P=0.004). Negative margins led to a significant improvement in PFS (HR =0.30; 95% CI, 0.16-0.57; P<0.001) and DFS (HR =0.30; 95% CI, 0.16-0.57; P<0.001). Those who received radiation had a non-significantly improved OS, PFS, and DFS (P>0.05). CONCLUSIONS: Our study corroborated that patients treated with adjuvant therapy after surgical resection had an mOS benefit as reported on prior phase III clinical trials. Patients with "borderline-resectable" pancreatic cancer are encouraged to participate in a clinical trial or clinically be treated with adjuvant therapy until more mature results from the ongoing perioperative prospective study are available.

Correction to: Evaluation of the bioequivalence and food effect on the bioavailability of CC-486 (oral azacitidine) tablets in adult patients with cancer.

In the original publication of the article the author has found few incorrect values in the Table 1.

A Comparative Analysis of Tumors and Plasma Circulating Tumor DNA in 145 Advanced Cancer Patients Annotated by 3 Core Cellular Processes.

Matched-targeted and immune checkpoint therapies have improved survival in cancer patients, but tumor heterogeneity contributes to drug resistance. Our study categorized gene mutations from next generation sequencing (NGS) into three core processes. This annotation helps decipher complex biologic interactions to guide therapy. We collected NGS data on 145 patients who have failed standard therapy (2016 to 2018). One hundred and forty two patients had data for tissue (Caris MI/X) and plasma cell-free circulating tumor DNA (Guardant360) platforms. The mutated genes were categorized into cell fate (CF), cell survival (CS), and genome maintenance (GM). Comparative analysis was performed for concordance and discordance, unclassified mutations, trends in TP53 alterations, and PD-L1 expression. Two gene mutation maps were generated to compare each NGS platform. Mutated genes predominantly matched to CS with concordance between Guardant360 (64.4%) and Caris (51.5%). TP53 alterations comprised a significant proportion of the mutation pool in Caris and Guardant360, 14.7% and 13.1%, respectively. Twenty-six potentially actionable gene alterations were detected from matching ctDNA to Caris unclassified alterations. The CS core cellular process was the most prevalent in our study population. Clinical trials are warranted to investigate biomarkers for the three core cellular processes in advanced cancer patients to define the next best therapies.

Evaluation of the bioequivalence and food effect on the bioavailability of CC-486 (oral azacitidine) tablets in adult patients with cancer.

PURPOSE: CC-486 is an oral formulation of azacitidine that allows for extended dosing schedules to prolong azacitidine exposure to malignant cells and maximize clinical activity. CC-486 300 mg daily, administered for 14 or 21 days of 28-day treatment cycles, is currently under investigation in two ongoing phase III trials. The 300-mg daily dose in these studies is administered as two 150-mg tablets (Formulation A). METHODS: We evaluated the bioequivalence of one 300-mg CC-486 tablet (Formulation B) with Formulation A and food effect on Formulation B, in adult patients with cancer in a 2-stage crossover design study. RESULTS: The ratios of the geometric means of the maximum azacitidine plasma concentration (Cmax) and of the area under the plasma concentration-time curve from time 0 extrapolated to infinity (AUC∞) were 101.5% and 105.7%, demonstrating the bioequivalence of Formulations A and B. Formulation B was rapidly absorbed under fasted and fed conditions. The geometric mean of Cmax was significantly decreased by ~ 21% in the fed state. Median Tmax was reached at 2 h and 1 h post-dose in fed and fasted states, respectively (P < 0.001). Nevertheless, systemic drug exposure (AUC) in fed and fasted states was within the 80-125% boundaries of bioequivalence and differences in Cmax and Tmax are not expected to have a clinical impact. CONCLUSION: The single 300-mg CC-486 tablet was bioequivalent to two 150-mg tablets, which have shown to be efficacious and generally well-tolerated in clinical trials, and can be taken with or without food.

Exposure to proton pump inhibitors and risk of pancreatic cancer: a meta-analysis.

Objectives: To estimate the pancreatic cancer risk among subjects exposed versus not exposed to proton pump inhibitors.Methods: The authors searched PubMed, EMBASE, Scopus, Cochrane Library, and clinicaltrials.gov to identify relevant studies. The authors quantified pancreatic cancer risk among subjects exposed versus not exposed to PPIs, expressed as the pooled (adjusted) odds ratio (OR/aOR) and 95% confidence interval (95%CI) in overall and sensitivity analyses.Results: One randomized trial, two cohort, four case-control, and five nested case-control studies with 700,178 subjects (73,985 cases; 626,193 controls) were retained. PPI exposure was associated with pancreatic cancer risk (OR = 1.75, 95%CI = 1.12-2.72, I2 = 99%); confirmed in sensitivity analyses for high-quality studies, observational studies, case-control studies, studies with pancreatic cancer as the primary outcome, and in sensitivity analyses for diabetes and obesity but not for pancreatitis and smoking. This association was independent of the duration and Defined Daily Dose of PPI exposure. Rabeprazole had a singular significant association with pancreatic cancer (OR = 5.40, 95%CI = 1.98-14.703, I2 = 87.9%).Conclusion: The class of PPIs is associated with a 1.75-fold increase in pancreatic cancer risk, confirmed in sensitivity analyses.

Response Rate Following Albumin-Bound Paclitaxel Plus Gemcitabine Plus Cisplatin Treatment Among Patients With Advanced Pancreatic Cancer: A Phase 1b/2 Pilot Clinical Trial.

Importance: Genomes of metastatic pancreatic cancers frequently contain intrachromosomal aberrations, indicating a DNA repair deficiency associated with sensitivity to DNA damaging agents, such as platinum. Objective: To determine response rate following treatment with nab-paclitaxel plus gemcitabine plus platinum-based cisplatin for patients with metastatic pancreatic ductal adenocarcinoma (PDA). Design, Setting, and Participants: This was a single-arm, open-label, phase 1b/2 clinical trial of nab-paclitaxel plus gemcitabine plus cisplatin treatment in which 25 patients with previously untreated metastatic PDA were enrolled. The trial was conducted from December 2013 to July 2016 at 3 US sites, with the last patient receiving study treatment at the end of October 2016, and the study closing January 2018. Interventions: Patients were treated with nab-paclitaxel plus gemcitabine plus various doses of cisplatin, 25 mg/m2, 37.5 mg/m2, and 50 mg/m2, on days 1 and 8 of a 21-day cycle. Main Outcomes and Measures: Primary end point was complete response rate as assessed by Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST), and levels of carbohydrate antigen 19-9 (or in nonexpressers, carbohydrate antigen 125 or carcinoembryonic antigen). Efficacy analysis included evaluable patients (those who received at least 1 dose of study treatment and had at least 1 postbaseline tumor assessment). Results: Of 25 patients enrolled in the study, the median (range) age was 65.0 (47.0-79.0) years, 14 (56%) were men, and most (24) were white (96%). The maximum tolerable dose of cisplatin was 25 mg/m2. The most common treatment-related adverse events grade 3 or higher were thrombocytopenia (17 patients [68%]), anemia (8 patients [32%]), and neutropenia (6 patients [24%]). Fatal events occurred for 3 patients (12%); 2 were related to study participation. A median (range) of 8 (1-15) cycles was completed. The RECIST responses in 24 evaluable patients included 2 complete responses (8%), which was below the primary end point of 25%, 15 partial responses (62%), 4 stable disease (17%), and 3 progressive disease (12%), with median overall survival of 16.4 (95% CI, 10.2-25.3) months; 16 patients (64%) were alive at 1 year, 10 (40%) at 2 years, 4 (16%) at 3 years, and 1 (4%) at 4 plus years. Overall survival ranged from 36 to 59 months. Median progression-free survival was 10.1 (95% CI, 6.0-12.5) months. Thus, the overall response rate was 71%, and the disease control rate was 88%. Conclusions and Relevance: This triple drug regimen showed substantial clinical activity in this small study. Although the primary end point was not reached, the high overall response rate, disease control rate, and median survival time among patients with advanced PDA treated with this combination are encouraging. The regimen is being studied in patients with PDA in the neoadjuvant setting and in patients with advanced biliary cancers. Trial Registration: ClinicalTrials.gov identifier: NCT01893801.