PIK3R5 genetic predictors of hypertension induced by VEGF-pathway inhibitors.

No biomarkers are available to predict patients at risk of developing hypertension induced by VEGF-pathway inhibitors. This study aimed to identify predictive biomarkers of hypertension induced by these drugs using a discovery-replication approach. The discovery set included 140 sorafenib-treated patients (TARGET study) genotyped for 973 SNPs in 56 genes. The most statistically significant SNPs associated with grade ≥2 hypertension were tested for association with grade ≥2 hypertension in the replication set of a GWAS of 1039 bevacizumab-treated patients from four clinical trials (CALGB/Alliance). In the discovery set, rs444904 (G > A) in PIK3R5 was associated with an increased risk of sorafenib-induced hypertension (p = 0.006, OR = 3.88 95% CI 1.54-9.81). In the replication set, rs427554 (G > A) in PIK3R5 (in complete linkage disequilibrium with rs444904) was associated with an increased risk of bevacizumab-induced hypertension (p = 0.008, OR = 1.39, 95% CI 1.09-1.78). This study identified a predictive marker of drug-induced hypertension that should be evaluated for other VEGF-pathway inhibitors.ClinicalTrials.gov Identifier:NCT00073307 (TARGET).

KDR genetic predictor of toxicities induced by sorafenib and regorafenib.

No biomarkers are available to predict toxicities induced by VEGFR TKIs. This study aimed to identify markers of toxicities induced by these drugs using a discovery-validation approach. The discovery set included 140 sorafenib-treated cancer patients (TARGET study) genotyped for SNPs in 56 genes. The most significant SNPs associated with grade ≥2 hypertension, diarrhea, dermatologic toxicities, and composite toxicity (any one of the toxicities) were tested for association with grade ≥2 toxicity in a validation set of 201 sorafenib-treated patients (Alliance/CALGB 80802). The validated SNP was tested for association with grade ≥2 toxicity in 107 (LCCC 1029) and 82 (Italian cohort) regorafenib-treated patients. SNP-toxicity associations were evaluated using logistic regression, and a meta-analysis between the studies was performed by inverse variance. Variant rs4864950 in KDR increased the risk of grade ≥2 composite toxicity in TARGET, Alliance/CALGB 80802, and the Italian cohort (meta-analysis p = 6.79 × 10-4, OR = 2.01, 95% CI 1.34-3.01). We identified a predictor of toxicities induced by VEGFR TKIs. CLINICALTRIALS.GOV IDENTIFIER: NCT00073307 (TARGET), NCT01015833 (Alliance/CALGB 80802), and NCT01298570 (LCCC 1029).

Molecular predictors of prevention of recurrence in HCC with sorafenib as adjuvant treatment and prognostic factors in the phase 3 STORM trial.

OBJECTIVE: Sorafenib is the standard systemic therapy for advanced hepatocellular carcinoma (HCC). Survival benefits of resection/local ablation for early HCC are compromised by 70% 5-year recurrence rates. The phase 3 STORM trial comparing sorafenib with placebo as adjuvant treatment did not achieve its primary endpoint of improving recurrence-free survival (RFS). The biomarker companion study BIOSTORM aims to define (A) predictors of recurrence prevention with sorafenib and (B) prognostic factors with B level of evidence. DESIGN: Tumour tissue from 188 patients randomised to receive sorafenib (83) or placebo (105) in the STORM trial was collected. Analyses included gene expression profiling, targeted exome sequencing (19 known oncodrivers), immunohistochemistry (pERK, pVEGFR2, Ki67), fluorescence in situ hybridisation (VEGFA) and immunome. A gene signature capturing improved RFS in sorafenib-treated patients was generated. All 70 RFS events were recurrences, thus time to recurrence equalled RFS. Predictive and prognostic value was assessed using Cox regression models and interaction test. RESULTS: BIOSTORM recapitulates clinicopathological characteristics of STORM. None of the biomarkers tested (related to angiogenesis and proliferation) or previously proposed gene signatures, or mutations predicted sorafenib benefit or recurrence. A newly generated 146-gene signature identifying 30% of patients captured benefit to sorafenib in terms of RFS (p of interaction=0.04). These sorafenib RFS responders were significantly enriched in CD4+ T, B and cytolytic natural killer cells, and lacked activated adaptive immune components. Hepatocytic pERK (HR=2.41; p=0.012) and microvascular invasion (HR=2.09; p=0.017) were independent prognostic factors. CONCLUSION: In BIOSTORM, only hepatocytic pERK and microvascular invasion predicted poor RFS. No mutation, gene amplification or previously proposed gene signatures predicted sorafenib benefit. A newly generated multigene signature associated with improved RFS on sorafenib warrants further validation. TRIAL REGISTRATION NUMBER: NCT00692770.

AKT1 (E17K) mutation profiling in breast cancer: prevalence, concurrent oncogenic alterations, and blood-based detection.

BACKGROUND: The single hotspot mutation AKT1 [G49A:E17K] has been described in several cancers, with the highest incidence observed in breast cancer. However, its precise role in disease etiology remains unknown. METHODS: We analyzed more than 600 breast cancer tumor samples and circulating tumor DNA for AKT1 (E17K) and alterations in other cancer-associated genes using Beads, Emulsions, Amplification, and Magnetics digital polymerase chain reaction technology and targeted exome sequencing. RESULTS: Overall AKT1 (E17K) mutation prevalence was 6.3 % and not correlated with age or menopausal stage. AKT1 (E17K) mutation frequency tended to be lower in patients with grade 3 disease (1.9 %) compared with those with grade 1 (11.1 %) or grade 2 (6 %) disease. In two cohorts of patients with advanced metastatic disease, 98.0 % (n = 50) and 97.1 % (n = 35) concordance was obtained between tissue and blood samples for the AKT1 (E17K) mutation, and mutation capture rates of 66.7 % (2/3) and 85.7 % (6/7) in blood versus tissue samples were observed. Although AKT1-mutant tumor specimens were often found to harbor concurrent alterations in other driver genes, a subset of specimens harboring AKT1 (E17K) as the only known driver alteration was also identified. Initial follow-up survival data suggest that AKT1 (E17K) could be associated with increased mortality. These findings warrant additional long-term follow-up. CONCLUSIONS: The data suggest that AKT1 (E17K) is the most likely disease driver in certain breast cancer patients. Blood-based mutation detection is achievable in advanced-stage disease. These findings underpin the need for a further enhanced-precision medicine paradigm in the treatment of breast cancer.

Sorafenib in radioactive iodine-refractory, locally advanced or metastatic differentiated thyroid cancer: a randomised, double-blind, phase 3 trial.

BACKGROUND: Patients with radioactive iodine ((131)I)-refractory locally advanced or metastatic differentiated thyroid cancer have a poor prognosis because of the absence of effective treatment options. In this study, we assessed the efficacy and safety of orally administered sorafenib in the treatment of patients with this type of cancer. METHODS: In this multicentre, randomised, double-blind, placebo-controlled, phase 3 trial (DECISION), we investigated sorafenib (400 mg orally twice daily) in patients with radioactive iodine-refractory locally advanced or metastatic differentiated thyroid cancer that had progressed within the past 14 months. Adult patients (≥18 years of age) with this type of cancer were enrolled from 77 centres in 18 countries. To be eligible for inclusion, participants had to have at least one measurable lesion by CT or MRI according to Response Evaluation Criteria In Solid Tumors (RECIST); Eastern Cooperative Oncology Group performance status 0-2; adequate bone marrow, liver, and renal function; and serum thyroid-stimulating hormone concentration lower than 0·5 mIU/L. An interactive voice response system was used to randomly allocate participants in a 1:1 ratio to either sorafenib or matching placebo. Patients, investigators, and the study sponsor were masked to treatment assignment. The primary endpoint was progression-free survival, assessed every 8 weeks by central independent review. Analysis was by intention to treat. Patients in the placebo group could cross over to open-label sorafenib upon disease progression. Archival tumour tissue was examined for BRAF and RAS mutations, and serum thyroglobulin was measured at baseline and at each visit. This study is registered with ClinicalTrials.gov, number NCT00984282, and with the EU Clinical Trials Register, number EudraCT 2009-012007-25. FINDINGS: Patients were randomly allocated on a 1:1 basis to sorafenib or placebo. The intention-to-treat population comprised 417 patients (207 in the sorafenib group and 210 in the placebo group) and the safety population was 416 patients (207 in the sorafenib group and 209 in the placebo group). Median progression-free survival was significantly longer in the sorafenib group (10·8 months) than in the placebo group (5·8 months; hazard ratio [HR] 0·59, 95% CI 0·45-0·76; p<0·0001). Progression-free survival improved in all prespecified clinical and genetic biomarker subgroups, irrespective of mutation status. Adverse events occurred in 204 of 207 (98·6%) patients receiving sorafenib during the double-blind period and in 183 of 209 (87·6%) patients receiving placebo. Most adverse events were grade 1 or 2. The most frequent treatment-emergent adverse events in the sorafenib group were hand-foot skin reaction (76·3%), diarrhoea (68·6%), alopecia (67·1%), and rash or desquamation (50·2%). INTERPRETATION: Sorafenib significantly improved progression-free survival compared with placebo in patients with progressive radioactive iodine-refractory differentiated thyroid cancer. Adverse events were consistent with the known safety profile of sorafenib. These results suggest that sorafenib is a new treatment option for patients with progressive radioactive iodine-refractory differentiated thyroid cancer. FUNDING: Bayer HealthCare Pharmaceuticals and Onyx Pharmaceuticals (an Amgen subsidiary).

Sorafenib plus dacarbazine in solid tumors: a phase I study with dynamic contrast-enhanced ultrasonography and genomic analysis of sequential tumor biopsy samples.

PURPOSE: Improved prognostic accuracy for treatment response and a wider understanding of drug effects in humans are crucial for enhancing the utility of sorafenib and other promising targeted therapies. We developed a strategy of global genomic investigation of sequential tumor biopsy samples at baseline and 21 days post treatment, and applied this approach in a phase I study of sorafenib plus dacarbazine in patients with solid tumors. The objective of this study was also to validate functional parameters of DCE-US as surrogate markers to predict earlier response. EXPERIMENTAL DESIGN: Patients received 21-day cycles of oral sorafenib, 400 mg twice daily and dacarbazine, 1,000 mg/m(2) in a 1-h intravenous infusion on day 1. Efficacy was assessed using response evaluation criteria in solid tumors. Sequential biopsy samples (baseline and day 21) were obtained from the same tumor. Changes from baseline in global gene expression (GE) measured by genomic microarrays and in tumor vascularity at baseline, D8, D21, D 42 and every 2 cycles using dynamic contrast-enhanced ultrasonography (DCE-US) were analyzed for patients with and without a clinical response to treatment at 3 months. RESULTS: Among 23 patients evaluable for treatment efficacy, 17 were eligible for gene expression and DCE-US analyses. One patient achieved a partial response; 14 exhibited stable disease. Ten patients were defined as exhibiting stable disease (SD) and 7, progressive disease (PD) at 3 months. Genomic analyses identified a 237-gene signature that distinguished SD from PD at 3 months. Of note, CDK4 overexpression and PDGFR downregulation were associated with PD. Functional parameters of DCE-US representing the blood volume at baseline, day 8, and day 21 were correlated with disease progression at 3 months. CONCLUSIONS: This novel approach of sequential investigations in a phase I trial was feasible, detecting early changes in gene expression and tumor vascularity evaluated using DCE-US that may be predictive of clinical outcome.

Pembrolizumab for advanced urothelial carcinoma: exploratory ctDNA biomarker analyses of the KEYNOTE-361 phase 3 trial.

Circulating tumor DNA (ctDNA) is emerging as a potential biomarker in early-stage urothelial cancer but its utility in metastatic disease remains unknown. In the phase 3 KEYNOTE-361 study, pembrolizumab with and without chemotherapy was compared with chemotherapy alone in patients with metastatic urothelial cancer. The study did not meet prespecified efficacy thresholds for statistical significance. To identify potential biomarkers of response, we retrospectively evaluated association of pre- and post-treatment ctDNA with clinical outcomes in a subset of patients who received pembrolizumab (n = 130) or chemotherapy (n = 130) in KEYNOTE-361. Baseline ctDNA were associated with best overall response (BOR;P = 0.009), progression-free survival (PFS;P < 0.001), and overall survival (OS;P < 0.001) for pembrolizumab, but not chemotherapy (all, P > 0.05). Chemotherapy induced larger ctDNA decreases from baseline to treatment cycle 2 than pembrolizumab; however, change with pembrolizumab (n = 87) were more associated with BOR (P = 4.39 × 10-5) and OS (P = 7.07 × 10-5) versus chemotherapy (n = 102; BOR: P = 1.01 × 10-4; OS: P = 0.018). Tumor tissue-informed versions of ctDNA change metrics were most associated with clinical outcomes but did not show statistically significant independent value for explaining OS beyond radiographic change by RECIST v1.1 when jointly modeled (pembrolizumab P = 0.364; chemotherapy P = 0.823). These results suggest distinct patterns in early ctDNA changes with immunotherapy and chemotherapy and differences in their association with long-term outcomes, which provide preliminary insights on the utility of liquid biopsies for treatment monitoring in metastatic urothelial cancer. Clinical trial registration: NCT02853305.

Changes in Circulating Tumor DNA Reflect Clinical Benefit Across Multiple Studies of Patients With Non-Small-Cell Lung Cancer Treated With Immune Checkpoint Inhibitors.

PURPOSE: As immune checkpoint inhibitors (ICI) become increasingly used in frontline settings, identifying early indicators of response is needed. Recent studies suggest a role for circulating tumor DNA (ctDNA) in monitoring response to ICI, but uncertainty exists in the generalizability of these studies. Here, the role of ctDNA for monitoring response to ICI is assessed through a standardized approach by assessing clinical trial data from five independent studies. PATIENTS AND METHODS: Patient-level clinical and ctDNA data were pooled and harmonized from 200 patients across five independent clinical trials investigating the treatment of patients with non-small-cell lung cancer with programmed cell death-1 (PD-1)/programmed death ligand-1 (PD-L1)-directed monotherapy or in combination with chemotherapy. CtDNA levels were measured using different ctDNA assays across the studies. Maximum variant allele frequencies were calculated using all somatic tumor-derived variants in each unique patient sample to correlate ctDNA changes with overall survival (OS) and progression-free survival (PFS). RESULTS: We observed strong associations between reductions in ctDNA levels from on-treatment liquid biopsies with improved OS (OS; hazard ratio, 2.28; 95% CI, 1.62 to 3.20; P < .001) and PFS (PFS; hazard ratio 1.76; 95% CI, 1.31 to 2.36; P < .001). Changes in the maximum variant allele frequencies ctDNA values showed strong association across different outcomes. CONCLUSION: In this pooled analysis of five independent clinical trials, consistent and robust associations between reductions in ctDNA and outcomes were found across multiple end points assessed in patients with non-small-cell lung cancer treated with an ICI. Additional tumor types, stages, and drug classes should be included in future analyses to further validate this. CtDNA may serve as an important tool in clinical development and an early indicator of treatment benefit.

Phase I Assessment of Safety and Therapeutic Activity of BAY1436032 in Patients with IDH1-Mutant Solid Tumors.

PURPOSE: BAY1436032, an inhibitor of mutant isocitrate dehydrogenase 1 (mIDH1), was active against multiple IDH1-R132X solid tumors in preclinical models. This first-in-human study was designed to determine the safety and pharmacokinetics of BAY1436032, and to evaluate its potential pharmacodynamics and antitumor effects. PATIENTS AND METHODS: The study comprised of dose escalation and dose expansion cohorts. BAY1436032 tablets were orally administered twice daily on a continuous basis in subjects with mIDH1 solid tumors. RESULTS: In dose escalation, 29 subjects with various tumor types were administered BAY1436032 across five doses (150-1,500 mg twice daily). BAY1432032 exhibited a relatively short half-life. Most evaluable subjects experienced target inhibition as indicated by a median maximal reduction of plasma R-2-hydroxyglutarate levels of 76%. BAY1436032 was well tolerated and an MTD was not identified. A dose of 1,500 mg twice daily was selected for dose expansion, where 52 subjects were treated in cohorts representing four different tumor types [lower grade glioma (LGG), glioblastoma, intrahepatic cholangiocarcinoma, and a basket cohort of other tumor types]. The best clinical outcomes were in subjects with LGG (n = 35), with an objective response rate of 11% (one complete response and three partial responses) and stable disease in 43%. As of August 2020, four of these subjects were in treatment for >2 years and still ongoing. Objective responses were observed only in LGG. CONCLUSIONS: BAY1436032 was well tolerated and showed evidence of target inhibition and durable objective responses in a small subset of subjects with LGG.

Correction to: Phase Ib Trial of the PI3K Inhibitor Copanlisib Combined with the Allosteric MEK Inhibitor Refametinib in Patients with Advanced Cancer.

The article Phase Ib Trial of the PI3K Inhibitor Copanlisib Combined with the Allosteric MEK Inhibitor Refametinib in Patients with Advanced Cancer.

Phase Ib Trial of the PI3K Inhibitor Copanlisib Combined with the Allosteric MEK Inhibitor Refametinib in Patients with Advanced Cancer.

BACKGROUND: Dual inhibition of PI3K and MAPK signaling is conceptually a promising anticancer therapy. OBJECTIVE: This phase 1b trial investigated the safety, maximum tolerated dose (MTD), recommended phase II dose, pharmacokinetics, tumor response, fluorodeoxyglucose positron emission tomography (FDG-PET) pharmacodynamics, and biomarker explorations for the combination of pan-PI3K inhibitor copanlisib and allosteric MEK inhibitor refametinib in patients with advanced solid tumors. PATIENTS AND METHODS: This was an adaptive trial with eight dose cohorts combining dose escalation and varying schedules in repeated 28-day cycles. Patients received copanlisib (0.2-0.8 mg/kg intravenously) intermittently (days 1, 8, 15) or weekly (days 1, 8, 15, 22) each cycle, and refametinib (30-50 mg twice daily orally) continuously or 4 days on/3 days off. Patients with KRAS, NRAS, BRAF, or PI3KCA mutations were eligible for the expansion cohort. RESULTS: In the dose-escalation (n = 49) and expansion (n = 15) cohorts, the most common treatment-emergent adverse events included diarrhea (59.4%), nausea, acneiform rash, and fatigue (51.6% each). Dose-limiting toxicities included oral mucositis (n = 4), increased alanine aminotransferase/aspartate aminotransferase (n = 3), rash acneiform, hypertension (n = 2 each), and diarrhea (n = 1). MTD was copanlisib 0.4 mg/kg weekly and refametinib 30 mg twice daily. No pharmacokinetic interactions were identified. Decreased tumor FDG uptake and MEK-ERK signaling inhibition were demonstrated during treatment. Best response was stable disease (n = 21); median treatment duration was 6 weeks. CONCLUSIONS: Despite sound rationale and demonstrable pharmacodynamic tumor activity in relevant tumor populations, a dose and schedule could not be identified for this drug combination that was both tolerable and offered clear efficacy in the population assessed. CLINICALTRIALS. GOV IDENTIFIER: NCT01392521.

Single-agent activity of phosphatidylinositol 3-kinase inhibition with copanlisib in patients with molecularly defined relapsed or refractory diffuse large B-cell lymphoma.

Patients with relapsed/refractory diffuse large B-cell lymphoma (DLBCL) have adverse outcomes. We evaluated the efficacy and safety of the phosphatidylinositol 3-kinase inhibitor copanlisib in patients with relapsed/refractory DLBCL and assessed the relationship between efficacy and DLBCL cell of origin (COO; activated B-cell like [ABC] and germinal center B-cell like [GCB]) and other biomarkers. The primary endpoint was objective response rate (ORR) in DLBCL COO subgroups (ABC, GCB, and unclassifiable) and by CD79B mutational status (NCT02391116). Sixty-seven patients received copanlisib (ABC DLBCL, n = 19; GCB DLBCL, n = 30; unclassifiable, n = 3; missing, n = 15). The ORR was 19.4%; 31.6% and 13.3% in ABC and GCB DLBCL patients, respectively. ORR was 22.2%/20.0% for patients with/without CD79B mutations (wild type, n = 45; mutant, n = 9; missing, n = 13). Overall median progression-free survival and duration of response were 1.8 and 4.3 months, respectively. Adverse events included hypertension (40.3%), diarrhea (37.3%), and hyperglycemia (32.8%). Aberrations were detected in 338 genes, including BCL2 (53.7%) and MLL2 (53.7%). A 16-gene signature separating responders from nonresponders was identified. Copanlisib treatment demonstrated a manageable safety profile in patients with relapsed/refractory DLBCL and a numerically higher response rate in ABC vs. GCB DLBCL patients.

Identification of Expression Profiles Defining Distinct Prognostic Subsets of Radioactive-Iodine Refractory Differentiated Thyroid Cancer from the DECISION Trial.

Several biomarkers have been suggested to have prognostic value in differentiated thyroid carcinomas (DTC) with no validation in the refractory setting, including all tumor subtypes. We aim to correlate RNA expression profiles with survival based on patients included in the DECISION trial. We obtained 247 samples from the 417 patients included in the DECISION study and performed RNAseq analysis (77 million paired-end reads for each sample on HiSeq2000). After quality control, 125 samples were included in the secondary analysis and mapped against the human reference genome (GRCh38) with STAR (v2.5.1b) using ENCODE parameter. Survival analysis was calculated using the Kaplan-Meier method and log-rank test was used for statistical comparison. In this post hoc analysis, we identified three groups of tumors based on their gene expression profile: BRAF-like, RAS-like, and non-BRAF-non-RAS-like (NoBRaL). No significant correlation with sorafenib responders was observed. However, we identified a statistically significant correlation between the RNA-expression profiles and progression-free survival. The BRAF-like profile had a significantly better outcome compared with RAS-like and NoBRaL (11.8, 6.2, and 5.5 months, respectively) [HR: 0.31, 95% confidence interval (CI), 0.17-0.60; P < 0.001 and HR: 0.36 (95% CI, 0.21-0.63); P < 0.001] and HR: 0.36 (95% CI, 0.21-0.63; P < 0.001) and maintained significance as an independent prognostic factor for overall survival in the multivariate analysis for papillary thyroid cancers. To our knowledge, this is the first comprehensive RNA-seq analysis of all histologic subtypes of DTC. The RNA expression profiles identified may suggest a new prognostic parameter to be considered before recommendation of systemic therapies or the design of stratification factors for future clinical trials.

On-Target Pharmacodynamic Activity of the PI3K Inhibitor Copanlisib in Paired Biopsies from Patients with Malignant Lymphoma and Advanced Solid Tumors.

The PI3K inhibitor copanlisib has efficacy and manageable safety in patients with indolent lymphoma and solid tumors. Pharmacodynamic effects relative to copanlisib dose and plasma exposure were evaluated. Patients with lymphoma or solid tumors received copanlisib 0.4 or 0.8 mg/kg on days 1, 8, and 15 of a 28-day cycle. Primary variables were maximum changes in phosphorylated AKT (pAKT) levels in platelet-rich plasma (PRP) and plasma glucose. Other evaluations included PI3K signaling markers and T-lymphocytes in paired tumor biopsies, the relationship between estimated plasma exposure and pharmacodynamic markers, response, and safety. Sixty-three patients received copanlisib. PRP pAKT levels showed sustained reductions from baseline following copanlisib [median inhibition: 0.4 mg/kg, 73.8% (range -94.9 to 144.0); 0.8 mg/kg, 79.6% (range -96.0 to 408.0)]. Tumor pAKT was reduced versus baseline with copanlisib 0.8 mg/kg in paired biopsy samples (P < 0.05). Dose-related transient plasma glucose elevations were observed. Estimated copanlisib plasma exposure significantly correlated with changes in plasma pAKT and glucose metabolism markers. There were two complete responses and six partial responses; seven of eight responders received copanlisib 0.8 mg/kg. Adverse events (all grade) included hyperglycemia (52.4%), fatigue (46.0%), and hypertension (41.3%). Copanlisib demonstrated dose-dependent pharmacodynamic evidence of target engagement and PI3K pathway modulation/inhibition in tumor and immune cells. Results support the use of copanlisib 0.8 mg/kg (or flat-dose equivalent of 60 mg) in solid tumors and lymphoma, and provide a biomarker hypothesis for studies of copanlisib combined with immune checkpoint inhibitors (NCT03711058).

Phase II multicenter, uncontrolled trial of sorafenib in patients with metastatic breast cancer.

This trial was conducted to assess the efficacy and safety of sorafenib in patients with metastatic breast cancer. In this multinational, open-label phase II study, patients with metastatic breast cancer that had progressed after at least one prior chemotherapy regimen were continuously treated with oral sorafenib, 400 mg twice daily. The primary endpoint was overall best response; a secondary endpoint was percentage of patients with stable disease for greater than or equal to 16 weeks. Biomarker analysis were also performed. Of the 56 patients enrolled into the study, 54 were treated with at least one dose of sorafenib. Partial response was observed in one patient (2%) and stable disease in 20 patients (37%); no complete responses were observed. Disease stabilization for greater than or equal to 16 weeks was seen in 12 patients (22%); stabilization for greater than or equal to 6 months in seven patients (13%). The most common drug-related grade 3 adverse events were rash/desquamation (6%), hand-foot skin reaction (4%), and fatigue (4%). Baseline vascular endothelial growth factor levels, levels of soluble epidermal growth factor receptor during treatment and both baseline and changes in soluble human epidermal growth factor receptor 2 levels correlated significantly with clinical outcomes. Although the primary endpoint of overall response rate showed minimal improvement on sorafenib 400 mg twice-daily treatment, the rate of disease stabilization was encouraging in patients treated with one or more lines of chemotherapy. The treatment had a clinically manageable toxicity profile. Further investigation of single-agent sorafenib in this patient population is not recommended; however, studies investigating combinations of sorafenib with chemotherapeutic agents are warranted and ongoing.

Analysis of Biomarkers and Association With Clinical Outcomes in Patients With Differentiated Thyroid Cancer: Subanalysis of the Sorafenib Phase III DECISION Trial.

PURPOSE: The phase III DECISION trial (NCT00984282; EudraCT:2009-012007-25) established sorafenib efficacy in locally recurrent or metastatic, progressive, differentiated thyroid cancer (DTC) refractory to radioactive iodine. We conducted a retrospective, exploratory biomarker analysis of patients from DECISION. EXPERIMENTAL DESIGN: Candidate biomarkers [15 baseline plasma proteins, baseline and during-treatment serum thyroglobulin, and relevant tumor mutations (BRAF, NRAS, HRAS, and KRAS)] were analyzed for correlation with clinical outcomes. RESULTS: Plasma biomarker and thyroglobulin data were available for 395 of 417 (94.7%) and 403 of 417 (96.6%) patients, respectively. Elevated baseline VEGFA was independently associated with poor prognosis for progression-free survival [PFS; HR = 1.82; 95% confidence interval (CI), 1.38-2.44; P = 0.0007], overall survival (HR = 2.13; 95% CI, 1.37-3.36; P = 0.013), and disease-control rate (DCR; OR = 0.30; P = 0.009). Elevated baseline thyroglobulin was independently associated with poor PFS (HR = 2.03; 95% CI, 1.52-2.71; P < 0.0001) and DCR (OR = 0.32; P = 0.01). Combined VEGFA/thyroglobulin signatures correlated with poor PFS (HR = 2.12; 95% CI, 1.57-2.87; P < 0.00001). Thyroglobulin decrease ≥30% from baseline was achieved by 76% and 14% of patients receiving sorafenib and placebo, respectively (P < 0.001). Patients with ≥30% thyroglobulin reduction had longer PFS than those without ≥30% reduction [HR (95% CI): sorafenib = 0.61 (0.40-0.94), P = 0.022; placebo = 0.49 (0.29-0.85), P = 0.009]. BRAF mutations were associated with better PFS; RAS mutations were associated with worse PFS, although neither was independently prognostic in multivariate models. No examined biomarker predicted sorafenib benefit. CONCLUSIONS: We identified biomarkers associated with poor prognosis in DTC, including elevated baseline VEGFA and thyroglobulin and the presence of RAS mutations. Serum thyroglobulin may be a biomarker of tumor response and progression.

Exposure-Response Modeling and Simulation of Progression-Free Survival and Adverse Events of Sorafenib Treatment in Patients With Advanced Thyroid Cancer.

Sorafenib is an oral multikinase inhibitor approved for the treatment of differentiated thyroid carcinoma (DTC), renal cell carcinoma, and hepatocellular carcinoma. In the phase III DECISION trial in patients with DTC, sorafenib exposure and the incidence of some adverse events (AEs) were higher than in previous trials; therefore, we analyzed exposure-response relationships, including progression-free survival (PFS) and selected AEs in patients with DTC. A novel, stratified prediction-corrected visual predictive check (pc-VPC) was developed to show robustness of the exposure-response relationships. Time-to-event simulations confirmed the benefit of the recommended dosing schedule of 800 mg/day: initial doses of 800 mg/day were associated with the highest PFS, whereas lower doses (600 or 400 mg/day) were associated with improved tolerability but reduced PFS. A simulated dose-reduction strategy of 800 mg/day for an initial two cycles followed by dose reductions seemed likely to maintain efficacy while possibly mitigating selected AEs (e.g., diarrhea and hand-foot skin reactions).

Genetic Variants of VEGFA and FLT4 Are Determinants of Survival in Renal Cell Carcinoma Patients Treated with Sorafenib.

Molecular markers of sorafenib efficacy in patients with metastatic renal cell carcinoma (mRCC) are not available. The purpose of this study was to discover genetic markers of survival in patients with mRCC treated with sorafenib. Germline variants from 56 genes were genotyped in 295 patients with mRCC. Variant-overall survival (OS) associations were tested in multivariate regression models. Mechanistic studies were conducted to validate clinical associations. VEGFA rs1885657, ITGAV rs3816375, and WWOX rs8047917 (sorafenib arm), and FLT4 rs307826 and VEGFA rs3024987 (sorafenib and placebo arms combined) were associated with shorter OS. FLT4 rs307826 increased VEGFR-3 phosphorylation, membrane trafficking, and receptor activation. VEGFA rs1885657 and rs58159269 increased transcriptional activity of the constructs containing these variants in endothelial and RCC cell lines, and VEGFA rs58159269 increased endothelial cell proliferation and tube formation. FLT4 rs307826 and VEGFA rs58159269 led to reduced sorafenib cytotoxicity. Genetic variation in VEGFA and FLT4 could affect survival in sorafenib-treated patients with mRCC. These markers should be examined in additional malignancies treated with sorafenib and in other angiogenesis inhibitors used in mRCC. SIGNIFICANCE: Clinical and mechanistic data identify germline genetic variants in VEGFA and FLT4 as markers of survival in patients with metastatic renal cell carcinoma.