Prescribing Characteristics of Octreotide Immediate-Release and Long-Acting Release in Patients with Neuroendocrine Tumors.

BACKGROUND: Treatment recommendations for patients with neuroendocrine tumors (NETs) include the use of octreotide long-acting release (LAR) for long-term therapy and immediate-release (IR) as rescue therapy to control the breakthrough symptoms of carcinoid syndrome (CS). High doses of LAR are commonly used in clinical practice. This study aimed to evaluate the real-world utilization of LAR and preceding IR use at the prescription and patient levels. METHODS: We used an administrative claims database (2009-2018) containing privately insured enrollees. We calculated the normalized LAR dose from pharmacy claims and the initial mean IR daily dose at the prescription level. At the patient level, we conducted a retrospective cohort study that included patients continuously enrolled with ≥1 pharmacy claim of LAR and evaluated the frequency and the clinical reason for dose escalation of LAR. The definition of the above-label maximum dose of LAR was ≥30 mg/4 weeks. RESULTS: Nineteen percent of LAR prescriptions had an above-label maximum dose. Only 7% of LAR prescriptions had preceding IR use. There were 386 patients with NETs or CS vs. 570 with an unknown diagnosis. Comparing patients with NETs or CS to those with an unknown diagnosis, 22.3% vs. 11.0 % experienced dose escalations and 29.0% vs. 26.6% had IR use before dose escalation, respectively. LAR dose escalation occurred in 50.9% vs. 39.2% for symptom control, 12.3% vs. 7.1% for tumor progression control, and 16.6% vs. 6.0% for both reasons in NETs/CS and unknown groups, respectively. CONCLUSION: Octreotide LAR dosing above the label-maximum dose is common and IR rescue dosing appears to be underutilized.

Long-Term Treatment with Telotristat Ethyl in Patients with Carcinoid Syndrome Symptoms: Results from the TELEPATH Study.

INTRODUCTION: Telotristat ethyl is indicated for use in combination with somatostatin analogs (SSAs) to treat carcinoid syndrome (CS) diarrhea uncontrolled by SSAs alone in adults, but long-term safety and efficacy data beyond 48 weeks are needed. OBJECTIVES: The aims of the study were to evaluate the long-term safety and tolerability of telotristat ethyl and its effect on quality of life (QOL) in patients with CS. METHODS: In this phase 3, nonrandomized, multicenter, open-label, long-term extension study (TELEPATH), patients who participated in phase 2 or 3 trials of telotristat ethyl continued treatment at their present dose level (250 or 500 mg thrice daily) for 84 weeks. Safety and tolerability, the primary endpoint, were assessed by monitoring adverse events (AEs), serious AEs, AEs of special interest (AESIs; including liver-related AEs, depression, and gastrointestinal AEs), and deaths. The secondary objective was to evaluate changes in patients' QOL using validated cancer questionnaires and a subjective global assessment of CS symptoms. RESULTS: In 124 patients exposed to telotristat ethyl for a mean of 102.6 ± 53.2 weeks, the type and frequency of AEs were consistent with those reported in previous trials. The occurrence of AESIs was not related to dosage or duration of therapy. Most AEs were mild to moderate in severity, and no deaths were related to telotristat ethyl. QOL scores remained stable, and the majority of patients reported adequate symptom relief throughout the study. CONCLUSIONS: Safety results of TELEPATH support the long-term use of telotristat ethyl in patients with CS diarrhea. Telotristat ethyl was well-tolerated and associated with sustained improvement in QOL scores (NCT02026063).

Opportunities to Improve Symptom Control with Somatostatin Congeners in GEP-NETs: A Review of Key Issues.

Octreotide acetate (octreotide) is the most prescribed and most studied somatostatin congener, or analog, for gastroenteropancreatic neuroendocrine tumors (GEP-NETs) and carcinoid syndrome, the latter of which may be characterized by debilitating diarrhea and flushing. Approved in the U.S. more than 30 years ago, octreotide is widely used to control the symptoms of carcinoid syndrome and has been shown to demonstrate antiproliferative activity. The two formulations available in the U.S. include a subcutaneous immediate-release (IR) injection introduced in 1989 and a long-acting repeatable (LAR) intramuscular injection approved in 1999. Lanreotide depot (lanreotide), a more recent somatostatin congener, has been available in the U.S. since 2014. Despite widespread use of octreotide LAR, several key challenges exist with the current depot-based treatment paradigm. Studies indicate that LAR formulations are associated with continued unmet patient needs, owing in part to a loss of bioactivity over time that may necessitate progressive supplemental treatment with IR octreotide to adequately control symptoms. Clinicians should understand the key differences in the pharmacokinetic profiles of the LAR and IR formulations that may contribute to bioactivity loss and somatostatin receptor desensitization. In addition, there is a need to re-evaluate the role of IR octreotide in combination with depot therapy to provide consistent bioavailability and better control of carcinoid syndrome symptoms. The purpose of this review is to explore all these issues and to re-establish a rationale for the IR formulation, particularly with respect to novel use cases and its use during the COVID-19 pandemic. IMPLICATIONS FOR PRACTICE: There is a need to re-evaluate the role of immediate-release octreotide in combination with depot therapy to provide consistent bioavailability and better control of carcinoid syndrome symptoms.

Can an amino acid mixture alleviate gastrointestinal symptoms in neuroendocrine tumor patients?

BACKGROUND: Neuroendocrine tumors, although relatively rare in incidence, are now the second most prevalent gastrointestinal neoplasm owing to indolent disease biology. A small but significant sub-group of neuroendocrine tumor patients suffer from diarrhea. This is usually secondary to carcinoid syndrome but can also be a result of short gut syndrome, bile acid excess or iatrogenic etiologies. Recently, an amino acid based oral rehydration solution (enterade® Advanced Oncology Formula) was found to have anti-diarrheal properties in preclinical models. METHODS: A retrospective chart review of all NET patients treated with enterade® AO was performed after IRB approval. RESULTS: Ninety-eight NET patients who had received enterade® AO at our clinic from May 2017 through June 2019 were included. Patients (N = 49 of 98) with follow up data on bowel movements (BMs) were included for final analysis. Eighty-four percent of patients (41/49) had fewer BMs after taking enterade® AO and 66% (27/41) reported more than 50% reduction in BM frequency. The mean number of daily BMs was 6.6 (range, 3-20) at baseline before initiation of therapy, while the mean number of BMs at 1 week time point post enterade® AO was 2.9 (range, 0-11). CONCLUSIONS: Our retrospective observations are encouraging and support prospective validation with appropriate controls in NET patients. This is first published report of the potential anti-diarrheal activity of enterade® AO in NET patients.

Long-Term Safety Experience with Telotristat Ethyl Across Five Clinical Studies in Patients with Carcinoid Syndrome.

BACKGROUND: Patients with neuroendocrine tumors (NETs) and carcinoid syndrome experience considerable morbidity and mortality; carcinoid syndrome may be associated with shorter survival. Carcinoid syndrome is linked to tumoral secretion of serotonin and other bioactive substances. The subsequent debilitating diarrhea and urgency to defecate pose significant health risks. In previous studies, telotristat ethyl, a tryptophan hydroxylase inhibitor, was effective and well tolerated in treating carcinoid syndrome diarrhea. We present pooled safety data from five clinical trials with telotristat ethyl in patients with carcinoid syndrome. SUBJECTS, MATERIALS, AND METHODS: Adverse events reported during telotristat ethyl treatment were pooled from two phase II and three phase III clinical trials in 239 patients with carcinoid syndrome. Long-term safety of telotristat ethyl and causes of hospitalization and death were reviewed; overall survival was estimated. RESULTS: Mean (median; range) duration of exposure and follow-up was 1.3 years (1.1 years; 1 week to 5.7 years), with 309 total patient-years of exposure. Leading causes of hospitalization were gastrointestinal disorders or were related to the underlying tumor and related treatment. Survival estimates at 1, 2, and 3 years were 93%, 88%, and 77%. Nearly all deaths were due to progression or complication of the underlying disease; none were attributable to telotristat ethyl. There was one death in year 4. CONCLUSION: Based on long-term safety data, telotristat ethyl is well tolerated and has a favorable long-term safety profile in patients with carcinoid syndrome. IMPLICATIONS FOR PRACTICE: Carcinoid syndrome can cause persistent diarrhea, even in patients treated with somatostatin analogs. Across five clinical trials in patients with carcinoid syndrome, telotristat ethyl has been well tolerated and efficacious, providing clinicians with a new approach to help control carcinoid syndrome diarrhea, in addition to somatostatin analog therapy. By reducing the stool frequency in patients with carcinoid syndrome whose diarrhea is refractory to anticholinergics, such as loperamide and atropine/diphenoxylate, and somatostatin analog dose escalation, improvement in quality of life becomes an achievable goal.

Management of Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia: Review and a Single Center Experience.

BACKGROUND: Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare pulmonary condition, characterized by diffuse proliferation of neuroendocrine cells in the respiratory epithelium. DIPNECH lesions are less than 5 mm in size and are limited to the basement membrane with no invasion. There is limited information regarding epidemiology, natural history of disease progression, or the management of this rare entity. We present the experience of a center with extensive expertise in neuroendocrine disease. METHODS: A cohort of patients (N = 13) with DIPNECH treated and followed at our institution was identified. We describe the our approach to their care, our disease management and also provide a review of DIPNECH pathophysiology. RESULTS: Our patient cohort consisted of twelve females and one male with a mean age of 63 years at the time of diagnosis. Dyspnea on exertion and dry cough were the most common presenting symptoms. Two patients were under surveillance without treatment; three patients were treated with a short-acting somatostatin analog; three patients were treated with azithromycin alone; four were treated with a combination of long-acting monthly somatostatin analogs and azithromycin; one patient received a combination of long-acting somatostatin analog and everolimus. Five patients had concomitant bronchial carcinoids. CONCLUSIONS: DIPNECH is a rare pathology that can profoundly affect a patient's quality of life. Paroxysmal coughing episodes can be difficult to treat. Our limited single center experience shows encouraging response to use of somatostatin analogs, azithromycin, and everolimus in the management of debilitating DIPNECH associated symptoms.

Comprehensive genomic profiling in routine clinical practice leads to a low rate of benefit from genotype-directed therapy.

BACKGROUND: Describe a single-center real-world experience with comprehensive genomic profiling (CGP) to identify genotype directed therapy (GDT) options for patients with malignancies refractory to standard treatment options. METHODS: Patients who had CGP by a CLIA-certified laboratory between November 2012 and December 2015 were included. The medical records were analyzed retrospectively after Institutional Review Board (IRB) approval. The treating oncologist made the decision to obtain the assay to provide potential therapeutic options. The objectives of this study were to determine the proportion of patients who benefited from GDT, and to identify barriers to receiving GDT. RESULTS: A total of 125 pediatric and adult patients with a histologically confirmed diagnosis of malignancy were included. Among these, 106 samples were from adult patients, and 19 samples were from pediatric patients. The median age was 54 years for adults. The majority had stage IV malignancy (53%) and were pretreated with 2-3 lines of therapy (45%). The median age was 8 years for pediatric patients. The majority had brain tumors (47%) and had received none or 1 line of therapy (58%) when the profiling was requested. A total of 111 (92%) patients had genomic alterations and were candidates for GDT either via on/off-label use or a clinical trial (phase 1 through 3). Fifteen patients (12%) received GDT based on these results including two patients who were referred for genomically matched phase 1 clinical trials. Three patients (2%) derived benefit from their GDT that ranged from 2 to 6 months of stable disease. CONCLUSIONS: CGP revealed potential treatment options in the majority of patients profiled. However, multiple barriers to therapy were identified, and only a small minority of the patients derived benefit from GDT.

Defining the optimal timing of adjuvant therapy for resected pancreatic adenocarcinoma: A statewide cancer registry analysis.

BACKGROUND: Long-term results of the ESPAC-3 trial suggest that while completing adjuvant therapy (AT) is necessary after resection of pancreatic ductal adenocarcinoma (PDAC), early initiation (within 8 weeks) may not be associated with improved overall survival (OS). The primary aim of this study was to evaluate the OS impact of early versus late AT in a statewide analysis. METHODS: Patients with stages I-III PDAC in the Kentucky Cancer Registry (KCR) from 2004 to 2013, were evaluated. Those undergoing pancreatectomy were stratified into two groups ("early," <8 weeks, vs. "late," 8-16 weeks). RESULTS: Of 2,221 diagnosed patients with stages I-III, 831 (37.4%) underwent pancreatectomy upfront. Of these, only 420 (50.5%) received AT. Initiation date of AT was not associated with OS (median OS: early, 20.2 vs. late, 19.0 months, P = 0.97). On multivariate analysis, factors that affected OS included stage (II, HR-1.82, P = 0.017; III, HR-3.77, P < 0.001), node positivity (HR-1.51, P = 0.004), poorly/undifferentiated grade (HR-1.34; P = 0.011), but not AT initiation date. CONCLUSIONS: In this statewide analysis, there was no difference in OS between early and late AT initiation for resected PDAC. The ideal window for AT initiation remains unknown as tumor biology continues to trump regimens from the past decade. J. Surg. Oncol. 2016;114:451-455. © 2016 Wiley Periodicals, Inc.

Impact of Previous Somatostatin Analogue Use on the Activity of Everolimus in Patients with Advanced Neuroendocrine Tumors: Analysis from the Phase III RADIANT-2 Trial.

BACKGROUND/AIMS: The phase III placebo-controlled RADIANT-2 trial investigated the efficacy of everolimus plus octreotide long-acting repeatable (LAR) in patients with advanced neuroendocrine tumors (NET) associated with carcinoid syndrome. Here we report a secondary analysis based on the previous somatostatin analogue (SSA) exposure status of patients enrolled in RADIANT-2. METHODS: Patients were randomly assigned to receive oral everolimus 10 mg/day plus octreotide LAR 30 mg intramuscularly (i.m.) or to receive matching placebo plus octreotide LAR 30 mg i.m. every 28 days. SSA treatment before study enrollment was permitted. Patient characteristics and progression-free survival (PFS) were analyzed by treatment arm and previous SSA exposure status. RESULTS: Of the 429 patients enrolled in RADIANT-2, 339 were previously exposed to SSA (95% received octreotide); 173 of 339 patients were in the everolimus plus octreotide LAR arm. All patients had a protocol-specified history of secretory symptoms, but analysis by type showed that more patients who previously received SSA therapy had a history of flushing symptoms (77%), diarrhea (86%), or both (63%) compared with SSA-naive patients (62, 62, and 24%, respectively). Patients who received everolimus plus octreotide LAR had longer median PFS regardless of previous SSA exposure (with: PFS 14.3 months, 95% confidence interval, CI, 12.0-20.1; without: 25.2 months, 95% CI, 12.0-not reached) compared with patients who received placebo plus octreotide LAR (with: 11.1 months, 95% CI, 8.4-14.6; without: 13.6 months, 95% CI, 8.2-22.7). CONCLUSION: Everolimus in combination with octreotide improves PFS in patients with advanced NET associated with carcinoid syndrome, regardless of previous SSA exposure.

Inhibition of ribonucleotide reductase subunit M2 enhances the radiosensitivity of metastatic pancreatic neuroendocrine tumor.

Ribonucleotide Reductase (RNR) is a rate-limiting enzyme in the production of deoxyribonucleoside triphosphates (dNTPs), which are essential substrates for DNA repair after radiation damage. We explored the radiosensitization property of RNR and investigated a selective RRM2 inhibitor, 3-AP, as a radiosensitizer in the treatment of metastatic pNETs. We investigated the role of RNR subunit, RRM2, in pancreatic neuroendocrine (pNET) cells and responses to radiation in vitro. We also evaluated the selective RRM2 subunit inhibitor, 3-AP, as a radiosensitizer to treat pNET metastases in vivo. Knockdown of RNR subunits demonstrated that RRM1 and RRM2 subunits, but not p53R3, play significant roles in cell proliferation. RRM2 inhibition activated DDR pathways through phosphorylation of ATM and DNA-PK protein kinases but not ATR. RRM2 inhibition also induced Chk1 and Chk2 phosphorylation, resulting in G1/S phase cell cycle arrest. RRM2 inhibition sensitized pNET cells to radiotherapy and induced apoptosis in vitro. In vivo, we utilized pNET subcutaneous and lung metastasis models to examine the rationale for RNR-targeted therapy and 3-AP as a radiosensitizer in treating pNETs. Combination treatment significantly increased apoptosis of BON (human pNET) xenografts and significantly reduced the burden of lung metastases. Together, our results demonstrate that selective RRM2 inhibition induced radiosensitivity of metastatic pNETs both in vitro and in vivo. Therefore, treatment with the selective RRM2 inhibitor, 3-AP, is a promising radiosensitizer in the therapeutic armamentarium for metastatic pNETs.

Deregulation of Wnt/ß-catenin signaling through genetic or epigenetic alterations in human neuroendocrine tumors.

Carcinoid tumors are rare neuroendocrine tumors (NETs) that are increasing in incidence. Mutation and altered expression of Wnt/ß-catenin signaling components have been described in many tumors but have not been well-studied in NETs. Here, we observed accumulation of ß-catenin in the cytoplasm and/or nucleus in 25% of clinical NET tissues. By mutational analysis, the mutations of ß-catenin (I35S) and APC (E1317Q, T1493T) were identified in NET cells and the tissues. Expression of representative Wnt inhibitors was absent or markedly decreased in BON, a human pancreatic carcinoid cell line; treatment with 5-aza-2'-deoxycytidine (5-aza-CdR) increased expression levels of the Wnt inhibitors. Methylation analyses demonstrated that CpG islands of SFRP-1 and Axin-2 were methylated, whereas the promoters of DKK-1, DKK-3 and WIF-1 were unmethylated in four NET cells. Aberrant methylation of SFRP-1 was particularly observed in most of clinical NET tissues. In addition, the repression of these unmethylated genes was associated with histone H3 lysine 9 dimethylation (H3K9me2) in BON cells. Together, 5-aza-CdR treatment inhibited cell proliferation and decreased the protein levels of H3K9me2 and G9a. Moreover, a novel G9a inhibitor, UNC0638, suppressed BON cell proliferation through inhibition of Wnt/ß-catenin pathway. Overexpression of the inhibitory genes, particularly SFRP-1 and WIF-1 in BON cells, resulted in suppression of anchorage-independent growth and inhibition of tumor growth in mice. Our findings suggest that aberrant Wnt/ß-catenin signaling, through either mutations or epigenetic silencing of Wnt antagonists, contributes to the pathogenesis and growth of NETs and have important clinical implications for the prognosis and treatment of NETs.

Everolimus plus octreotide long-acting repeatable in patients with colorectal neuroendocrine tumors: a subgroup analysis of the phase III RADIANT-2 study.

INTRODUCTION: The incidence of colorectal neuroendocrine tumors (NETs) is increasing, and patients with this disease have particularly poor prognoses. Treatment options are limited, and survival times have not improved in the past decade. METHODS: A post hoc analysis of the efficacy and tolerability of everolimus plus octreotide long-acting repeatable (LAR) was conducted in patients with colorectal NETs enrolled in the phase III RAD001 in Advanced Neuroendocrine Tumors, Second Trial (RADIANT-2) study. The primary endpoint (progression-free survival [PFS]), secondary endpoints (including objective response rate), and safety were assessed. RESULTS: Patients with colorectal NETs receiving everolimus plus octreotide LAR had a significantly longer median PFS (29.9 months; n = 19) than did those receiving placebo plus octreotide LAR (6.6 months; n = 20). Everolimus plus octreotide LAR treatment also significantly reduced the risk for disease progression (hazard ratio: 0.34; 95% confidence interval: 0.13-0.89; p = .011). Although no objective responses were observed, tumor shrinkage was more frequently noted in the everolimus plus octreotide LAR arm than in the placebo plus octreotide LAR arm (67% vs. 37%, respectively). The combination of everolimus plus octreotide LAR was generally well tolerated by patients with colorectal NETs; rash and stomatitis were the most commonly reported adverse events. CONCLUSIONS: Everolimus plus octreotide LAR treatment had significant benefits and improved outcomes for patients with advanced colorectal NETs compared with placebo plus octreotide LAR treatment. Results of this exploratory analysis are consistent with those reported from the RADIANT-2 primary analysis. These findings support additional investigations of everolimus plus octreotide LAR in patients with colorectal NETs.

hPG80 (Circulating Progastrin), a Novel Blood-Based Biomarker for Detection of Poorly Differentiated Neuroendocrine Carcinoma and Well Differentiated Neuroendocrine Tumors.

Current blood-based biomarkers for neuroendocrine neoplasms (NENs) lack both sensitivity and specificity. Human circulating progastrin (hPG80) is a novel biomarker that can be easily measured in plasma by ELISA. This study is the first to examine hPG80 in NENs. Plasma hPG80 was quantified from 95 stage IV NEN patients, using DxPG80 technology (ECS Progastrin, Switzerland) and compared with hPG80 concentrations in two cohorts of healthy donor controls aged 50-80 (n = 252) and 18-25 (n = 137). Median hPG80 in NENs patients was 5.54 pM compared to 1.5 pM for the 50-80 controls and 0.29 pM the 18-25 cohort (p < 0.0001). Subgroup analysis revealed median hPG80 levels significantly higher than for either control cohort in neuroendocrine carcinoma (NEC; n = 25) and neuroendocrine tumors (NET; n = 70) including the small-cell lung cancer (SCLC) sub-cohort (n = 13). Diagnostic accuracy, estimated by AUCs, was high for NENs, as well as both sub-groups (NEC/NET) when compared to the younger and older control groups. Plasma hPG80 in NENs may be a diagnostic blood biomarker for both low- and high-grade NENs; further study is warranted. A prospective multi-center trial is ongoing in NET to evaluate hPG80 as a means of monitoring disease (NCT04750954).

68Ga-DOTATATE PET/CT: The Optimum Standardized Uptake Value (SUV) Internal Reference.

RATIONALE AND OBJECTIVES: Standardized Uptake Value (SUV) is an important semiquantitative measurement used in the clinical and research domains to assess radiopharmaceutical concentration in tumors versus normal organs, but is susceptible to many factors beyond the tumor biological environment. So, the aim of this study is to identify the optimum internal reference among organs with physiological uptake in 68Ga-DOTATATE PET/CT (DOTA PET/CT) scans. MATERIALS AND METHODS: This HIPAA-compliant, IRB-approved study with waiver of consent included retrospective imaging review of 180 consecutive patients with neuroendocrine tumors presenting for DOTA PET/CT image acquisition: Ga-68 DOTATATE dose was reported as (0.054 mCi/Kg) scans between September 2018 and May 2019. Mean value of body weight normalized SUV (SUVbw) and lean body mass normalized SUV (SUL) of liver and spleen were measured. Information about the patients and scan characteristics were collected. The paired Grambsch test was used to compare variance among the measured SUVs. Spearman's rank correlation coefficient was used to assess correlation between SUVs and potential patient- and scan-specific confounding factors. RESULTS: Variance of SUL was significantly lower than variance of SUVbw in both liver and spleen (p-value < 0.0001). Variances of liver SUVbw and SUL were significantly lower than the corresponding spleen SUVs. Liver SUL showed the lowest variance (3.69% ± 1.25%) among all measured SUVs. CONCLUSION: SUL is a more reproducible, less variable, and therefore more reliable quantitative measure in DOTA PET/CT scans, compared SUVbw. Among the available organs with physiological uptake, liver SUL is the optimum internal reference given the liver's larger size and uniform SUL values resulting in lower variability and better reproducibility.

Management of Large Cell Neuroendocrine Carcinoma.

BACKGROUND: Large cell neuroendocrine carcinoma (LCNEC) is a rare, aggressive cancer with a dismal prognosis. The majority of cases occur in the lung and the gastrointestinal tract; however, it can occur throughout the body. Recently advances in the understanding of the molecular underpinnings of this disease have paved the way for additional novel promising therapies. This review will discuss the current best evidence for management of LCNEC and new directions in the classification and treatment of this rare disease. METHODS: We performed a PubMed search for "Large cell neuroendocrine carcinoma" and "High grade neuroendocrine carcinoma." All titles were screened for relevance to the management of LCNEC. Papers were included based on relevance to the management of LCNEC. RESULTS: Papers were included reviewing both pulmonary and extra pulmonary LCNEC. We summarized the data driven best practices for the management of both early and advanced stage LCNEC. We describe emerging therapies with promising potential. DISCUSSION: LCNEC are rare and aggressive neoplasms. In advanced disease, the historical regimen of platinum based therapy in combination with etoposide or irinotecan remains among the commonly used first line therapies, however for extra thoracic LCNEC regimens like FOLFOX, FOLFOIRI and CAPTEM can also be used. Further effective and safe treatment options are desperately needed. Recently, new advances including a new understanding of the genetic subcategories of LCNEC and immunotherapy agents may guide further treatments.

Time to Sustained Improvement in Bowel Movement Frequency with Telotristat Ethyl: Analyses of Phase III Studies in Carcinoid Syndrome.

BACKGROUND: Telotristat ethyl is approved to treat carcinoid syndrome diarrhea in combination with somatostatin analogs. In TELESTAR and TELECAST phase III studies, patients with carcinoid syndrome received telotristat ethyl 250 or 500 mg 3 times per day (tid) or placebo tid in addition to somatostatin analogs. The aim of this prespecified analysis was to examine the time to reductions in bowel movements (BMs) in the TELESTAR and TELECAST studies using survival analysis methods. METHODS: First occurrence of sustained response was defined as the time to the first day of 2 consecutive weeks with a mean BM frequency improvement of ≥ 30% from baseline during the 12-week double-blind treatment periods. Time to first ≥ 30% worsening in BM frequency was also measured. Treatments were compared with the log-rank test; Cox regression models provided point and confidence interval estimates of the hazard ratios for each trial. RESULTS: In TELESTAR and TELECAST, majority of patients (69%) on telotristat ethyl experienced a sustained ≥ 30% improvement in BM frequency. The median time to sustained reduction of at least 30% in BM frequency was significantly faster (fewer days to onset) for telotristat ethyl compared with placebo in both TELESTAR (250 mg, HR = 2.3 [95% CI, 1.3-4.1, P = 0.004]; 500 mg, HR = 2.2 [95% CI, 1.2-3.9, P = 0.009]) and TELECAST (250 mg, HR = 3.9 [95% CI, 1.6-11.1, P = 0.003]; 500 mg, HR = 4.2 [95% CI, 1.7-11.7, P = 0.002]). In TELECAST, 42% of patients on placebo experienced sustained worsening in BM frequency compared with 20% on telotristat ethyl; no significant difference was observed in TELESTAR. CONCLUSION: The time of onset of sustained BM frequency improvement mean and range are important when considering use of telotristat ethyl in patients with carcinoid syndrome diarrhea. Telotristat ethyl may also reduce sustained worsening in BM frequency. TRIAL REGISTRATION: ClinicalTrials.gov Identifiers: NCT01677910, NCT02063659.

PI3K/mTOR Dual Inhibitor PF-04691502 Is a Schedule-Dependent Radiosensitizer for Gastroenteropancreatic Neuroendocrine Tumors.

Patients with advanced-stage gastroenteropancreatic neuroendocrine tumors (GEP-NETs) have a poor overall prognosis despite chemotherapy and radiotherapy (e.g., peptide receptor radionuclide therapy (PRRT)). Better treatment options are needed to improve disease regression and patient survival. The purpose of this study was to examine a new treatment strategy by combining PI3K/mTOR dual inhibition and radiotherapy. First, we assessed the efficacy of two PI3K/mTOR dual inhibitors, PF-04691502 and PKI-402, to inhibit pAkt and increase apoptosis in NET cell lines (BON and QGP-1) and patient-derived tumor spheroids as single agents or combined with radiotherapy (XRT). Treatment with PF-04691502 decreased pAkt (Ser473) expression for up to 72 h compared with the control; in contrast, decreased pAkt expression was noted for less than 24 h with PKI-402. Simultaneous treatment with PF-04691502 and XRT did not induce apoptosis in NET cells; however, the addition of PF-04691502 48 h after XRT significantly increased apoptosis compared to PF-04691502 or XRT treatment alone. Our results demonstrate that schedule-dependent administration of a PI3K/mTOR inhibitor, combined with XRT, can enhance cytotoxicity by promoting the radiosensitivity of NET cells. Moreover, our findings suggest that radiotherapy, in combination with timed PI3K/mTOR inhibition, may be a promising therapeutic regimen for patients with GEP-NET.

Benchmarks for Academic Oncology Faculty.

The role of clinical researchers is vital to cancer progress. The teaching, research, and leadership roles that academic oncologists hold need to be accounted for and appropriately compensated. National metrics are currently inexistent, but are necessary to move the oncology research field forward. Clinical research and routine clinical care must be harmoniously integrated without competing. This article reviews the national landscape of clinical cancer research and proposes a call for action.

A phase I/II study of rovalpituzumab tesirine in delta-like 3-expressing advanced solid tumors.

Delta-like protein 3 (DLL3) is highly expressed in solid tumors, including neuroendocrine carcinomas/neuroendocrine tumors (NEC/NET). Rovalpituzumab tesirine (Rova-T) is a DLL3-targeting antibody-drug conjugate. Patients with NECs and other advanced DLL3-expressing tumors were enrolled in this phase I/II study (NCT02709889). The primary endpoint was safety. Two hundred patients were enrolled: 101 with NEC/NET (large-cell NEC, gastroenteropancreatic NEC, neuroendocrine prostate cancer, and other NEC/NET) and 99 with other solid tumors (melanoma, medullary thyroid cancer [MTC], glioblastoma, and other). The recommended phase II dose (RP2D) was 0.3 mg/kg every 6 weeks (q6w) for two cycles. At the RP2D, grade 3/4 adverse events included anemia (17%), thrombocytopenia (15%), and elevated aspartate aminotransferase (8%). Responses were confirmed in 15/145 patients (10%) treated at 0.3 mg/kg, including 9/69 patients (13%) with NEC/NET. Rova-T at 0.3 mg/kg q6w had manageable toxicity, with antitumor activity observed in patients with NEC/NET, melanoma, MTC, and glioblastoma.