Lori J. Wirth

Cabozantinib in Progressive Medullary Thyroid Cancer

PURPOSE Cabozantinib, a tyrosine kinase inhibitor (TKI) of hepatocyte growth factor receptor (MET), vascular endothelial growth factor receptor 2, and rearranged during transfection (RET), demonstrated clinical activity in patients with medullary thyroid cancer (MTC) in phase I. PATIENTS AND METHODS We conducted a double-blind, phase III trial comparing cabozantinib with placebo in 330 patients with documented radiographic progression of metastatic MTC. Patients were randomly assigned (2:1) to cabozantinib (140 mg per day) or placebo. The primary end point was progression-free survival (PFS). Additional outcome measures included tumor response rate, overall survival, and safety. RESULTS The estimated median PFS was 11.2 months for cabozantinib versus 4.0 months for placebo (hazard ratio, 0.28; 95% CI, 0.19 to 0.40; P < .001). Prolonged PFS with cabozantinib was observed across all subgroups including by age, prior TKI treatment, and RET mutation status (hereditary or sporadic). Response rate was 28% for cabozantinib and 0% for placebo; responses were seen regardless of RET mutation status. Kaplan-Meier estimates of patients alive and progression-free at 1 year are 47.3% for cabozantinib and 7.2% for placebo. Common cabozantinib-associated adverse events included diarrhea, palmar-plantar erythrodysesthesia, decreased weight and appetite, nausea, and fatigue and resulted in dose reductions in 79% and holds in 65% of patients. Adverse events led to treatment discontinuation in 16% of cabozantinib-treated patients and in 8% of placebo-treated patients. CONCLUSION Cabozantinib (140 mg per day) achieved a statistically significant improvement of PFS in patients with progressive metastatic MTC and represents an important new treatment option for patients with this rare disease. This dose of cabozantinib was associated with significant but manageable toxicity.

Motesanib diphosphate in progressive differentiated thyroid cancer

BACKGROUND The expression of vascular endothelial growth factor (VEGF) is characteristic of differentiated thyroid cancer and is associated with aggressive tumor behavior and a poor clinical outcome. Motesanib diphosphate (AMG 706) is a novel oral inhibitor of VEGF receptors, platelet-derived growth-factor receptor, and KIT. METHODS In an open-label, single-group, phase 2 study, we treated 93 patients who had progressive, locally advanced or metastatic, radioiodine-resistant differentiated thyroid cancer with 125 mg of motesanib diphosphate, administered orally once daily. The primary end point was an objective response as assessed by an independent radiographic review. Additional end points included the duration of the response, progression-free survival, safety, and changes in serum thyroglobulin concentration. RESULTS Of the 93 patients, 57 (61%) had papillary thyroid carcinoma. The objective response rate was 14%. Stable disease was achieved in 67% of the patients, and stable disease was maintained for 24 weeks or longer in 35%; 8% had progressive disease as the best response. The Kaplan-Meier estimate of the median duration of the response was 32 weeks (the lower limit of the 95% confidence interval [CI] was 24; the upper limit could not be estimated because of an insufficient number of events); the estimate of median progression-free survival was 40 weeks (95% CI, 32 to 50). Among the 75 patients in whom thyroglobulin analysis was performed, 81% had decreased serum thyroglobulin concentrations during treatment, as compared with baseline levels. The most common treatment-related adverse events were diarrhea (in 59% of the patients), hypertension (56%), fatigue (46%), and weight loss (40%). CONCLUSIONS Motesanib diphosphate can induce partial responses in patients with advanced or metastatic differentiated thyroid cancer that is progressive. (ClinicalTrials.gov number, NCT00121628.)

Lenvatinib versus Placebo in Radioiodine-Refractory Thyroid Cancer

BACKGROUND Lenvatinib, an oral inhibitor of vascular endothelial growth factor receptors 1, 2, and 3, fibroblast growth factor receptors 1 through 4, platelet-derived growth factor receptor α, RET, and KIT, showed clinical activity in a phase 2 study involving patients with differentiated thyroid cancer that was refractory to radioiodine (iodine-131). METHODS In our phase 3, randomized, double-blind, multicenter study involving patients with progressive thyroid cancer that was refractory to iodine-131, we randomly assigned 261 patients to receive lenvatinib (at a daily dose of 24 mg per day in 28-day cycles) and 131 patients to receive placebo. At the time of disease progression, patients in the placebo group could receive open-label lenvatinib. The primary end point was progression-free survival. Secondary end points included the response rate, overall survival, and safety. RESULTS The median progression-free survival was 18.3 months in the lenvatinib group and 3.6 months in the placebo group (hazard ratio for progression or death, 0.21; 99% confidence interval, 0.14 to 0.31; P<0.001). A progression-free survival benefit associated with lenvatinib was observed in all prespecified subgroups. The response rate was 64.8% in the lenvatinib group (4 complete responses and 165 partial responses) and 1.5% in the placebo group (P<0.001). The median overall survival was not reached in either group. Treatment-related adverse effects of any grade, which occurred in more than 40% of patients in the lenvatinib group, were hypertension (in 67.8% of the patients), diarrhea (in 59.4%), fatigue or asthenia (in 59.0%), decreased appetite (in 50.2%), decreased weight (in 46.4%), and nausea (in 41.0%). Discontinuations of the study drug because of adverse effects occurred in 37 patients who received lenvatinib (14.2%) and 3 patients who received placebo (2.3%). In the lenvatinib group, 6 of 20 deaths that occurred during the treatment period were considered to be drug-related. CONCLUSIONS Lenvatinib, as compared with placebo, was associated with significant improvements in progression-free survival and the response rate among patients with iodine-131-refractory thyroid cancer. Patients who received lenvatinib had more adverse effects. (Funded by Eisai; SELECT ClinicalTrials.gov number, NCT01321554.).

Phase II Study of Safety and Efficacy of Motesanib in Patients With Progressive or Symptomatic, Advanced or Metastatic Medullary Thyroid Cancer

PURPOSE This phase II study investigated the efficacy and tolerability of motesanib, an investigational, highly selective inhibitor of vascular endothelial growth factor receptors 1, 2, and 3; platelet-derived growth factor receptor; and Kit in advanced medullary thyroid cancer (MTC). PATIENTS AND METHODS Patients with locally advanced or metastatic, progressive or symptomatic MTC received motesanib 125 mg/d orally for up to 48 weeks or until unacceptable toxicity or disease progression. The primary end point was objective response by independent review. Other end points included duration of response, progression-free survival, safety, pharmacokinetics, and changes in tumor markers. RESULTS Of 91 enrolled patients who received motesanib, two (2%) achieved objective response (95% CI, 0.3% to 7.7%); their duration of response was 32 weeks (censored) and 21 weeks (disease progressed). Eighty-one percent of patients had stable disease (48% had durable stable disease > or = 24 weeks), 8% had disease progression as best response, and 9% were not evaluated; 76% experienced a decrease from baseline in target lesion measurement. Median progression-free survival was 48 weeks (95% CI, 43 to 56 weeks). Among patients with tumor marker analysis, 69 (83%) of 83 and 63 (75%) of 84 had decreased serum calcitonin and carcinoembryonic antigen during treatment, respectively, compared with baseline. The most common treatment-related adverse events were diarrhea (41%), fatigue (41%), hypothyroidism (29%), hypertension (27%), and anorexia (27%). In pharmacokinetic analyses, motesanib trough concentrations were lower compared with differentiated thyroid cancer patients from the same study. CONCLUSION Although the objective response rate was low, a significant proportion of MTC patients (81%) achieved stable disease while receiving motesanib.

Dose to Larynx Predicts for Swallowing Complications After Intensity-Modulated Radiotherapy

PURPOSE To evaluate early swallowing after intensity-modulated radiotherapy for head and neck squamous cell carcinoma and determine factors correlating with aspiration and/or stricture. METHODS AND MATERIALS Consecutive patients treated with intensity-modulated radiotherapy with or without chemotherapy between September 2004 and August 2006 at the Dana Farber Cancer Institute/Brigham and Womens Hospital were evaluated with institutional review board approval. Patients underwent swallowing evaluation after completion of therapy; including video swallow studies. The clinical- and treatment-related variables were examined for correlation with aspiration or strictures, as well as doses to the larynx, pharyngeal constrictor muscles, and cervical esophagus. The correlation was assessed with logistic regression analysis. RESULTS A total of 96 patients were evaluated. Their median age was 55 years, and 79 (82%) were men. The primary site of cancer was the oropharynx in 43, hypopharynx/larynx in 17, oral cavity in 13, nasopharynx in 11, maxillary sinus in 2, and unknown primary in 10. Of the 96 patients, 85% underwent definitive RT and 15% postoperative RT. Also, 28 patients underwent induction chemotherapy followed by concurrent chemotherapy, 59 received concurrent chemotherapy, and 9 patients underwent RT alone. The median follow-up was 10 months. Of the 96 patients, 31 (32%) had clinically significant aspiration and 36 (37%) developed a stricture. The radiation dose-volume metrics, including the volume of the larynx receiving >or=50 Gy (p = 0.04 and p = 0.03, respectively) and volume of the inferior constrictor receiving >or=50 Gy (p = 0.05 and p = 0.02, respectively) were significantly associated with both aspiration and stricture. The mean larynx dose correlated with aspiration (p = 0.003). Smoking history was the only clinical factor to correlate with stricture (p = 0.05) but not aspiration. CONCLUSION Aspiration and stricture are common side effects after intensity-modulated radiotherapy for head-and-neck squamous cell carcinoma. The dose given to the larynx and inferior constrictors correlated with these side effects.

Phase I Study of Gefitinib Plus Celecoxib in Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck

PURPOSE Effective and tolerable palliative treatments are needed for patients with incurable squamous cell carcinoma of the head and neck (SCCHN). Single-agent targeted therapies have limited activity in this setting. The feasibility of adding celecoxib to gefitinib for the treatment of incurable SCCHN is unknown. PATIENTS AND METHODS Nineteen patients with unresectable recurrent locoregional and/or distant metastatic SCCHN with progressive disease after at least one prior chemotherapy or chemoradiotherapy regimen were enrolled onto this single-institution phase I study. Three dose levels were explored: (1) celecoxib 200 mg twice daily plus gefitinib 250 mg daily; (2) celecoxib 400 mg twice daily plus gefitinib 250 mg daily; and (3) celecoxib 400 mg twice daily plus gefitinib 500 mg daily. RESULTS No dose-limiting toxicities were encountered at any dose level. The most common toxicities were acneiform rash, diarrhea, hand reaction, dyspepsia, and anemia. Four of 18 patients assessable for response (22%; 95% CI, 2% to 42%) achieved a confirmed partial response. CONCLUSION The combination of gefitinib 500 mg daily plus celecoxib 400 mg twice daily is well-tolerated. The encouraging responses seen in this early study suggest further evaluation of epidermal growth factor receptor and cyclooxygenase-2 inhibitors in SCCHN is warranted.

Sequential therapy for the locally advanced larynx and hypopharynx cancer subgroup in TAX 324: survival, surgery, and organ preservation

BACKGROUND Locally advanced laryngeal and hypopharyngeal cancers (LHC) represent a group of cancers for which surgery, laryngectomy-free survival (LFS), overall survival (OS), and progression-free survival (PFS) are clinically meaningful end points. PATIENTS AND METHODS These outcomes were analyzed in the subgroup of assessable LHC patients enrolled in TAX 324, a phase III trial of sequential therapy comparing docetaxel plus cisplatin and fluorouracil (TPF) against cisplatin and fluorouracil (PF), followed by chemoradiotherapy. RESULTS Among 501 patients enrolled in TAX 324, 166 had LHC (TPF, n = 90; PF, n = 76). Patient characteristics were similar between subgroups. Median OS for TPF was 59 months [95% confidence interval (CI): 31-not reached] versus 24 months (95% CI: 13-42) for PF [hazard ratio (HR) for death: 0.62; 95% CI: 0.41-0.94; P = 0.024]. Median PFS for TPF was 21 months (95% CI: 12-59) versus 11 months (95% CI: 8-14) for PF (HR: 0.66; 95% CI: 0.45-0.97; P = 0.032). Among operable patients (TPF, n = 67; PF, n = 56), LFS was significantly greater with TPF (HR: 0.59; 95% CI: 0.37-0.95; P = 0.030). Three-year LFS with TPF was 52% versus 32% for PF. Fewer TPF patients had surgery (22% versus 42%; P = 0.030). CONCLUSIONS In locally advanced LHC, sequential therapy with induction TPF significantly improved survival and PFS versus PF. Among operable patients, TPF also significantly improved LFS and PFS. These results support the use of sequential TPF followed by carboplatin chemoradiotherapy as a treatment option for organ preservation or to improve survival in locally advanced LHC.

Dysphagia after sequential chemoradiation therapy for advanced head and neck cancer

OBJECTIVES: Assess impact of sequential chemoradiation therapy (SCRT) for advanced head and neck cancer (HNCA) on swallowing, nutrition, and quality of life. STUDY DESIGN: Prospective cohort study of 59 patients undergoing SCRT for advanced head and neck cancer. Follow-up median was 47.5 months. SETTING: Regional Cancer Center. RESULTS: Median time to gastrostomy tube removal was 21 weeks. Eighteen of 23 patients who underwent modified barium swallow demonstrated aspiration; none developed pneumonia. Six of 7 with pharyngoesophageal stricture underwent successful dilatation. Functional Assessment of Cancer Therapy—Head and Neck Scale questionnaires at median 6 months after treatment revealed “somewhat” satisfaction with swallowing. At the time of analysis, 97% have the gastronomy tube removed and take soft/regular diet. CONCLUSION: Early after treatment dysphagia adversely affected weight, modified barium swallow results, and quality of life. Diligent swallow therapy, and dilation as needed, allowed nearly all patients to have their gastronomy tubes removed and return to a soft/regular diet. SIGNIFICANCE: Dysphagia is significant after SCRT but generally slowly recovers 6 to 12 months after SCRT.

Redifferentiation of Iodine-Refractory BRAF V600E-Mutant Metastatic Papillary Thyroid Cancer with Dabrafenib

Purpose: To determine whether the selective BRAF inhibitor, dabrafenib, can stimulate radioiodine uptake in BRAF V600E-mutated unresectable or metastatic iodine-refractory papillary thyroid cancer (PTC). Experimental Design: Ten patients with BRAF V600E-mutant iodine-refractory PTC were enrolled. Absence of radioiodine uptake on iodine-131 whole body scan obtained within 14 months of study entry was required. Each patient received dabrafenib (150 mg twice daily) for 25 days before thyrotropin α-stimulated iodine-131 whole body scan (4 mCi/148 MBq). Patients whose scan showed new sites of radioiodine uptake remained on dabrafenib for 17 more days, and then were treated with 150 mCi (5.5 GBq) iodine-131. The primary endpoint of the study was the percentage of patients with new radioiodine uptake after treatment with dabrafenib. Results: Six of 10 patients (60%) demonstrated new radioiodine uptake on whole body scan after treatment with dabrafenib. All 6 were treated with 5.5 GBq iodine-131. Two patients had partial responses and 4 patients had stable disease on standard radiographic restaging at 3 months. Thyroglobulin decreased in 4 of 6 treated patients. One patient developed squamous cell carcinoma of the skin. There were no other significant adverse events attributed to dabrafenib. Conclusions: Dabrafenib can stimulate radioiodine uptake in patients with metastatic BRAF V600E-mutant iodine-refractory PTC, representing a potential new therapeutic approach for these patients. Clin Cancer Res; 21(5); 1028–35. ©2014 AACR.

Pembrolizumab for platinum- and cetuximab-refractory head and neck cancer: Results from a single-arm, phase II study

Purpose There are no approved treatments for recurrent/metastatic head and neck squamous cell carcinoma refractory to platinum and cetuximab. In the single-arm, phase II KEYNOTE-055 study, we evaluated pembrolizumab, an anti-programmed death 1 receptor antibody, in this platinum- and cetuximab-pretreated population with poor prognosis. Methods Eligibility stipulated disease progression within 6 months of platinum and cetuximab treatment. Patients received pembrolizumab 200 mg every 3 weeks. Imaging was performed every 6 to 9 weeks. Primary end points: overall response rate (Response Evaluation Criteria in Solid Tumors v1.1, central review) and safety. Efficacy was assessed in all dosed patients and in subgroups on the basis of programmed death ligand 1 (PD-L1) expression and human papillomavirus (HPV) status. Results Among 171 patients treated, 75% received two or more prior lines of therapy for metastatic disease, 82% were PD-L1 positive, and 22% were HPV positive. At the time of analysis, 109 patients (64%) experienced a treatment-related adverse event; 26 patients (15%) experienced a grade ≥ 3 event. Seven patients (4%) discontinued treatment, and one died of treatment-related adverse events. Overall response rate was 16% (95% CI, 11% to 23%), with a median duration of response of 8 months (range, 2+ to 12+ months); 75% of responses were ongoing at the time of analysis. Response rates were similar in all HPV and PD-L1 subgroups. Median progression-free survival was 2.1 months, and median overall survival was 8 months. Conclusion Pembrolizumab exhibited clinically meaningful antitumor activity and an acceptable safety profile in recurrent/metastatic head and neck squamous cell carcinoma previously treated with platinum and cetuximab.