A PK-PD model linking biomarker dynamics to progression-free survival in patients treated with everolimus and sorafenib combination therapy, EVESOR phase I trial.

PURPOSE: The objective was to develop a pharmacokinetic-pharmacodynamic (PK-PD) model linking everolimus and sorafenib exposure with biomarker dynamics and progression-free survival (PFS) based on data from EVESOR trial in patients with solid tumors treated with everolimus and sorafenib combination therapy and to simulate alternative dosing schedules for sorafenib. PATIENTS AND METHODS: Everolimus (5-10 mg once daily, qd) and sorafenib (200-400 mg twice daily, bid) were administered according to four different dosing schedules in 43 solid tumor patients. Rich PK and PD sampling for serum angiogenesis biomarkers was performed. Baseline activation of RAS/RAF/ERK (MAPK) pathway was assessed by quantification of mRNA specific gene panel in tumor biopsies. The PK-PD modeling was performed using NONMEM® software. RESULTS: An indirect response PK-PD model linking sorafenib plasma exposure with soluble vascular endothelial growth factor receptor 2 (sVEGFR2) dynamics was developed. Progression-free survival (PFS) was described by a parametric time-to-event model. Higher decreases in sVEGFR2 at day 21 and higher baseline activation of MAPK pathway were associated with longer PFS (p = 0.002 and p = 0.007, respectively). The simulated schedule sorafenib 200 mg bid 5 days-on/2 days-off + continuous everolimus 5 mg qd was associated with median PFS of 4.3 months (95% CI 1.6-14.4), whereas the median PFS in the EVESOR trial was 3.6 months (95% CI 2.7-4.2, n = 43). CONCLUSION: Sorafenib 200 mg bid 5 days-on/2 days-off + everolimus 5 mg qd continuous was selected for an additional arm of EVESOR trial to evaluate whether this simulated schedule is associated with higher clinical benefit. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01932177.

TERT promoter mutations identify a high-risk group in metastasis-free advanced thyroid carcinoma.

BACKGROUND: TERT promoter mutations are associated with adverse clinicopathological characteristics in thyroid carcinomas and considered as a major indicator of poor outcomes. Nevertheless, most studies have pooled heterogeneous types of thyroid carcinomas and have been conducted retrospectively. We investigated the association between TERT promoter mutations and recurrence in a prospective series of 173 intermediate- to high-risk patients with thyroid cancer. PATIENTS: Patients referred for radioiodine treatment after thyroidectomy for intermediate- to high-risk differentiated thyroid carcinoma were included in a prospective observational study and tested for TERT promoter, BRAF, and RAS mutations of their primary tumours. We analysed the relationship between TERT promoter mutations and outcomes. RESULTS: The prevalence of TERT promoter mutations was 20.2% (35/173) in the total population. It was significantly higher in tumours harbouring aggressive histological features (poorly differentiated carcinoma, tall cell variant of papillary cancer or widely invasive follicular cancer) than in non-aggressive tumours: 32.7% (16/49) versus 15.3% (19/124; p = 0.020). TERT promoter mutations were also strongly associated with age ≥45 years (p = 0.005), pT4 stage (p = 0.015), metastatic disease (p = 0.014), and extrathyroidal extension (p = 0.002). TERT promoter mutations were associated with poor outcomes in the total population (p < 0.001) but not in the subgroup of non-metastatic patients (p = 0.051). However, they were associated with a worse outcome in patients both free of metastases and devoid of aggressive histological features. Neither BRAF nor RAS mutations were associated with event-free survival in non-metastatic patients. CONCLUSION: Although their prognostic value does not seem to overcome that of histology, TERT promoter mutations may help to better define the prognosis of localized thyroid cancer patients without aggressive histology.

Predictive factors of outcome in poorly differentiated thyroid carcinomas.

BACKGROUND: The prognosis of poorly differentiated thyroid carcinomas (PDTC) is heterogeneous though generally poor. The objectives of this study were to identify clinical and molecular factors of poor prognosis. METHODS: One hundred four consecutive patients treated for a PDTC between 01/01/2000 and 31/12/2010 were included in this study. A pathological review was done for all cases (blinded to clinical data and outcome). RESULTS: All patients underwent thyroidectomy. Adjuvant radioactive-iodine was administered in 95.2% of them. Tumours were pT3 or pT4 in 68.3% of cases and metastatic in 38.5% of patients. Extrathyroidal extension (ETE) was observed in 40% of patients. At the end of the initial treatment, only 37% of patients were considered in remission. Fifty-two patients (50%) became refractory to radioiodine during follow-up. The 5-year overall survival was 72.8% and the 5-year recurrence-free survival (RFS) was 45.3%. Remission after initial treatment was an independent factor of RFS (HR = 0.22; [0.10-0.49]). ETE was the only significant parameter influencing the overall survival in multivariate analysis. TERT promoter mutations at positions -124 (C228T) and -146 (C250T) were present in 38.1% of analysed patients and significantly associated with radioiodine resistance but not with overall survival. Half of TERT promoter mutant tumours harboured also RAS or BRAF mutations. CONCLUSION: PDTC form a heterogeneous group of patients with usual late-stage diagnosis, low radioactive iodine avidity and frequent metastatic spread. TERT promoter mutations could help to identify patients with high risk of radio-iodine refractoriness.