A dose-finding, pharmacokinetic and pharmacodynamic study of a novel schedule of flavopiridol in patients with advanced solid tumors.

PURPOSE: Based on the promising activity and tolerability of flavopiridol administered with a pharmacokinetically-derived dosing schedule in chronic lymphocytic leukemia (CLL), we conducted a phase I study using this schedule in patients with advanced solid tumors. EXPERIMENTAL DESIGN: Flavopiridol was given IV as a 30-min loading dose followed by a 4-hr infusion weekly for 4 weeks repeated every 6 weeks. Dose-escalation was in cohorts of three patients using the standard 3+3 phase I study design. Blood samples were obtained for pharmacokinetic and pharmacodynamic studies. RESULTS: Thirty-four eligible patients with advanced solid tumors received a total of 208 doses (median 7, range 1-24). Total doses ranged from 40 to 105 mg/m(2). The primary dose limiting toxicity was cytokine release syndrome (CKRS). No antitumor responses were observed. The mean peak plasma concentration across all doses was 1.65 ± 0.86 µM. Area under the concentration-versus-time curve ([Formula: see text]) ranged from 4.31 to 32.2 µM[Symbol: see text]hr with an overall mean of 13.6 ± 7.0 µM[Symbol: see text]hr. Plasma flavopiridol concentrations and AUC increased proportionally with dose. There was no correlation between cytokine levels and clinical outcomes. CONCLUSIONS: The maximum-tolerated dose of flavopiridol is 20 mg/m(2) bolus followed by 20 mg/m(2) infusion over 4 h given weekly for 4 weeks on a 6-week cycle in patients with advanced solid tumors. Flavopiridol PK was notably different, and there was a higher frequency of CKRS, despite prophylactic steroids, seen in this patient group compared to previous studies with CLL using a similar dosing schedule.

Lack of therapeutic effect of the histone deacetylase inhibitor vorinostat in patients with metastatic radioiodine-refractory thyroid carcinoma.

CONTEXT: Aberrant histone deacetylase activity is seen in a variety of malignancies, and histone deacetylase inhibitors such as vorinostat have been shown to induce cell death and sensitize cells to cytotoxic chemotherapy in thyroid cancer cell lines. This phase II study was undertaken to assess objective response to vorinostat in patients with advanced thyroid cancer. EXPERIMENTAL DESIGN: A total of 19 patients with differentiated thyroid cancer (n = 16) and medullary thyroid cancer (n = 3) were enrolled in the study. Patients received oral vorinostat at a starting dose of 200 mg twice daily, with dose adjustments allowed as necessary for toxicity. Patients were treated for 2 wk, followed by 1 wk off therapy (3-wk cycle) until disease progression or study withdrawal. Responses were measured by Response Evaluation Criteria in Solid Tumors criteria and correlated with tumor markers. RESULTS: No patient achieved a partial or complete response. Median duration of therapy in patients with differentiated thyroid cancer was 17 wk, whereas in medullary thyroid cancer patients it was 25 wk. Reasons for termination included progression of disease by RECIST criteria (n = 7), clinical progression (n = 3), and adverse events (AEs) (n = 9). AEs were primarily grade 1-3; no clinical grade 4 or grade 5 events were observed. Clinical grade 3 AEs consisted of fatigue, dehydration, ataxia, pneumonia, bruises, and deep vein thrombosis. Severe thrombocytopenia was seen in seven patients (grade 3, n = 5; grade 4, n = 2) and was associated with minor bleeding or bruises. CONCLUSIONS: Vorinostat at this dose and schedule is not an effective treatment for advanced thyroid cancer.

Cardiotoxicity of histone deacetylase inhibitor depsipeptide in patients with metastatic neuroendocrine tumors.

PURPOSE: This phase II study was undertaken to assess objective response and toxicity of histone deacetylase inhibitor depsipeptide in patients with neuroendocrine tumors. EXPERIMENTAL DESIGN: A total of 15 patients with metastatic neuroendocrine tumors received a 4-hour i.v. infusion of depsipeptide at 14 mg/m2 on days 1, 8, and 15 every 28 days. Tumor response was assessed at 8-week intervals using Response Evaluation Criteria in Solid Tumors. Most patients were chemo-naïve (n = 12) but receiving long-acting octreotide for carcinoid syndrome (n = 11). All patients had Eastern Cooperative Oncology Group performance status of 0 to 1. RESULTS: The study was terminated prematurely due to an unexpected high number of serious cardiac adverse events so the objective response rate could not be determined. A total of 77 doses of depsipeptide with a median of four doses (range, 2-13) per patient were administered. The most common adverse events included nausea (86%), anorexia (73%), vomiting (66%), and fatigue (73%). A sudden death attributed to possible fatal ventricular arrhythmia occurred within 24 hours after the fifth dose of depsipeptide. Furthermore, asymptomatic grade 2 ventricular tachycardia (n = 2) and prolonged QTc (n = 3) probably related to depsipeptide were observed. Plasma depsipeptide levels measured in a subset of patients failed to reveal differences among patients with or without cardiac adverse events. CONCLUSIONS: Depsipeptide was associated with a high number of potentially serious cardiac adverse events in patients with metastatic neuroendocrine tumor. As sudden death possibly associated with depsipeptide was observed in this trial, the risks for potentially life-threatening arrhythmia associated with this agent need to be comprehensively evaluated.

Phase II study of celecoxib in metastatic differentiated thyroid carcinoma.

CONTEXT: There is increased cyclooxygenase-2 (COX-2) expression in malignant thyroid nodules compared with nonneoplastic and benign thyroid tissue. OBJECTIVE: The objective of the study was to evaluate the efficacy of celecoxib, a selective COX-2 inhibitor, in treating patients with progressive metastatic differentiated thyroid cancer (DTC) and to explore the relationship of clinical response to tumor COX-2 expression with immunohistochemistry in a subset of patients. DESIGN: The study was a prospective phase II trial with Fleming single-stage design powered at 80% with a 5% rejection error to detect more than 20% progression-free survival at 12 months. SETTING: Ambulatory patients were from tertiary referral academic medical centers. PATIENTS: Patients in the study had progressive metastatic DTC and had failed prior standard therapy. INTERVENTION: Patients were treated with celecoxib 400 mg orally twice a day for 12 months. MAIN OUTCOME MEASURE: The main outcome measure was progression-free survival at 12 months of treatment using Response Evaluation Criteria in Solid Tumors and/or serum thyroglobulin. RESULTS: Twenty-three of 32 patients experienced progressive disease or stopped therapy due to toxicity, thus fulfilling the intent-to-treat study endpoint for celecoxib failure. One patient achieved partial response, and one patient completed 12 months of therapy progression-free. The patient with partial response was on therapy along with seven other patients when the study was terminated. CONCLUSIONS: Celecoxib 400 mg orally twice per day fails to halt progressive metastatic DTC in most patients.

Enteral feedings with comfort and safety.

Patients who are unable to eat by mouth can be fed in a manner that maintains the structural and functional integrity of the gastrointestinal tract. The appropriate choice of type of feeding tube to use is based on the reasons patients need to be tube fed and the expected duration of need for the tube. Once the tubes are placed, verification of placement is critical for safe use. Patients, family caregivers, and staff must assess for potential complications. Misplacement is the most common problem of feeding tubes. Life-threatening complications can include "refeed syndrome" and "buried bumper syndrome." Additional threats include contaminated tube feeding and inappropriate medication administration. Feeding too rapidly into the small intestine can cause necrosis of the small bowel. To maintain patient comfort, site care is critical. Nasogastric tubes can cause permanent deformity of the nares. Gastric drainage on the skin can cause painful excoriation that is difficult to manage. With careful monitoring of tube feedings, positive nutritional status can be achieved. A positive nutritional status assists in promoting health and immune function.

Phase II clinical trial of sorafenib in metastatic medullary thyroid cancer.

PURPOSE: Mutations in the RET proto-oncogene and vascular endothelial growth factor receptor (VEGFR) activity are critical in the pathogenesis of medullary thyroid cancer (MTC). Sorafenib, a multikinase inhibitor targeting Ret and VEGFR, showed antitumor activity in preclinical studies of MTC. PATIENTS AND METHODS: In this phase II trial of sorafenib in patients with advanced MTC, the primary end point was objective response. Secondary end points included toxicity assessment and response correlation with tumor markers, functional imaging, and RET mutations. Using a two-stage design, 16 or 25 patients were to be enrolled onto arms A (hereditary) and B (sporadic). Patients received sorafenib 400 mg orally twice daily. RESULTS: Of 16 patients treated in arm B, one achieved partial response (PR; 6.3%; 95% CI, 0.2% to 30.2%), 14 had stable disease (SD; 87.5%; 95% CI, 61.7% to 99.5%), and one was nonevaluable. In a post hoc analysis of 10 arm B patients with progressive disease (PD) before study, one patient had PR of 21+ months, four patients had SD >or= 15 months, four patients had SD

Phase II trial of sorafenib in metastatic thyroid cancer.

PURPOSE: Based on the pivotal role of Ras-Raf-MAP-ERK signaling and vascular endothelial growth factor (VEGF) in papillary thyroid cancer (PTC), we conducted a phase II clinical trial of sorafenib targeting RAF and VEGF receptor kinases in PTC. PATIENTS AND METHODS: The primary end point was the objective response rate. Secondary end points included response correlation with serum thyroglobulin (Tg); functional imaging; tumor genotype; and signaling inhibition in tumor biopsies. Using a Simon minimax two-stage design, 16 or 25 chemotherapy-naïve metastatic PTC patients were to be enrolled in arm A (accessible tumor for biopsy). Arm B patients had other subtypes of thyroid carcinoma or prior chemotherapy, and did not require tumor biopsies. Patients received 400 mg orally twice per day of sorafenib. Response was assessed every 2 months using RECIST (Response Evaluation Criteria in Solid Tumors). RESULTS: Of 41 PTC patients, six patients had a partial response (PR; 15%; 95% CI, 6 to 29) and 23 patients (56%; 95% CI, 40 to 72) had stable disease longer than 6 months. Median duration of PR was 7.5 months (range, 6 to 14). Median progression-free survival was 15 months (95% CI, 10 to 27.5). In 14 (78%) of 18 Tg-assessable PTC patients, Tg declined more than 25%. Common grade 3 adverse events included hand-foot skin reaction, musculoskeletal pain, and fatigue. BRAF mutation was detected in 17 (77%) of 22 PTCs analyzed. Four of 10 paired tumor biopsies from PTC patients showed a reduction in levels of vascular endothelial growth factor receptor phosphorylation, ERK phosphorylation, and in VEGF expression during sorafenib therapy. No PRs were noted among non-PTC patients. CONCLUSION: Sorafenib is reasonably well-tolerated therapy with clinical and biologic antitumor activity in metastatic PTC.