Background Dabrafenib (GSK2118436) is a potent ATP-competitive inhibitor of BRAF kinase and was highly selective for mutant BRAF in kinase panel screening, cell lines, and xenografts. Methods A Phase I trial of dabrafenib was conducted to evaluate safety and tolerability in patients with incurable solid tumours. Efficacy at the recommended Phase II dose (RP2D) was studied in patients with BRAF-mutant tumours, including those with non-V600E mutations, in three cohorts: (1) metastatic melanoma, (2) melanoma with untreated brain metastases, and (3) non-melanoma solid tumours. Findings 184 patients enrolled, and 150 mg twice daily was chosen as the RP2D, based on safety, pharmacokinetic, and pharmacodynamic data. At the RP2D in patients with V600 BRAF-mutant melanoma, a response rate of 69% (a confirmed response rate of 50%) was observed overall and a 78% response rate (a confirmed response rate of 56%) in V600E BRAF-mutant melanoma. In V600 BRAF-mutant melanoma, responses were durable, with 17 patients (47%) on treatment for more than 6 months and a median progression-free survival (PFS) of 5·5 months. Responses were observed in patients with non-V600E BRAF mutations, including V600K and V600G. In the RP2D expansion of melanoma with untreated brain metastases, nine of ten patients (90%) showed reduction in brain lesion size and the median PFS was 4.2 months. Among BRAF-mutant non-melanoma solid tumours, antitumour activity was observed in gastrointestinal stromal tumour, papillary thyroid, non-small cell lung, ovarian, and colorectal cancer. Interpretation Dabrafenib is a highly active inhibitor of V600-mutant BRAF with a high response rate in V600E melanoma, and is the first drug of its class to demonstrate activity in melanoma brain metastases. Funding This study was funded and sponsored by GlaxoSmithKline

Background Activating BRAF V600E mutations are found in approximately 1–2% of adenocarcinomas of the lung offering an opportunity to test targeted therapy for this disease. Dabrafenib is an oral selective inhibitor of the BRAF kinase. The aim of this study was to assess the clinical activity of dabrafenib in patients with advanced BRAF V600E-mutant non-small cell lung cancer (NSCLC). Methods In this phase 2, multicenter, nonrandomized, open-label study of previously treated and untreated patients with stage IV, metastatic NSCLC and BRAF V600E mutation, we evaluated the antitumor activity and safety of oral dabrafenib (150 mg twice daily). The primary endpoint was investigator-assessed overall response rate (ORR) in patients receiving ≥ 1 dose of study drug. Safety analysis was performed on the all-treated population (all previously treated and untreated patients receiving ≥ 1 dose of study drug). The study is ongoing but not enrolling participants in this cohort. This trial is registered with ClinicalTrials.gov, number NCT01336634. Findings Between August 2011 and February 2014 a total of 84 previously treated and untreated patients were enrolled. Investigator-assessed ORR for 78 pretreated patients was 33% (95% confidence interval [CI], 23·1 to 44·9). Independent review committee assessment of ORR was consistent with investigator-based assessment. Four of the six previously untreated patients had an objective response. One patient died on study due to intracranial hemorrhage that was considered by the investigator to be due to study drug. Serious adverse events were reported in 35 (42%) of 84 patients. The most frequent grade 3 or higher adverse events were cutaneous squamous cell carcinoma (10 [12%] of 84 patients), asthenia (4 [5%] of 84 patients), and basal cell carcinoma (4 [5%] of 84 patients). Interpretation This is, to our knowledge, the first prospective trial focusing on BRAF V600E-mutant NSCLC to show clinical activity of a BRAF inhibitor. The results presented here suggest that dabrafenib may represent a future treatment option for patients with BRAF V600E-mutant NSCLC, a population with limited therapeutic options. Funding This trial was funded by GlaxoSmithKline. Dabrafenib is an asset of Novartis AG as of March 2, 2015.

Positron emission tomography (PET) may increase the diagnostic accuracy and confirm the underlying neuropathologic changes of Alzheimer disease (AD). OBJECTIVE To determine the accuracy of antemortem [ 18 F]flortaucipir PET images for predicting the presence of AD-type tau pathology at autopsy. DESIGN, SETTING, AND PARTICIPANTS This diagnostic study (A16 primary cohort) was conducted from October 2015 to June 2018 at 28 study sites (27 in US sites and 1 in Australia). Individuals with a terminal illness who were older than 50 years and had a projected life expectancy of less than 6 months were enrolled. All participants underwent [ 18 F]flortaucipir PET imaging, and scans were interpreted by 5 independent nuclear medicine physicians or radiologists. Supplemental autopsy [ 18 F]flortaucipir images and pathological samples were also collected from 16 historically collected cases. A second study (FR01 validation study) was conducted from March 26 to April 26, 2019, in which 5 new readers assessed the original PET images for comparison to autopsy. MAIN OUTCOMES AND MEASURES [ 18 F]flortaucipir PET images were visually assessed and compared with immunohistochemical tau pathology. An AD tau pattern of flortaucipir retention was assessed for correspondence with a postmortem B3-level (Braak stage V or VI) pathological pattern of tau accumulation and to the presence of amyloid-β plaques sufficient to meet the criteria for high levels of AD neuropathological change. Success was defined as having at least 3 of the 5 readers above the lower bounds of the 95% CI for both sensitivity and specificity of 50% or greater. RESULTS A total of 156 patients were enrolled in the A16 study and underwent [ 18 F]flortaucipir PET imaging. Of these, 73 died during the study, and valid autopsies were performed for 67 of these patients. Three autopsies were evaluated as test cases and removed from the primary cohort (n = 64). Of the 64 primary cohort patients, 34 (53%) were women and 62 (97%) were white; mean (SD) age was 82.5 (9.6) years; and 49 (77%) had dementia, 1 (2%) had mild cognitive impairment, and 14 (22%) had normal cognition. Prespecified success criteria were met for the A16 primary cohort. The flortaucipir PET scans predicted a B3 level of tau pathology, with sensitivity ranging from 92.3% (95% CI, 79.7%-97.3%) to 100.0% (95% CI, 91.0%-100.0%) and specificity ranging from 52.0% (95% CI, 33.5%-70.0%) to 92.0% (95% CI, 75.0%-97.8%). A high level of AD neuropathological change was predicted with sensitivity of 94.7% (95% CI, 82.7%-98.5%) to 100.0% (95% CI, 90.8%-100.0%) and specificity of 50.0% (95% CI, 32.1%-67.9%) to 92.3% (95% CI, 75.9%-97.9%). The FR01 validation study also met prespecified success criteria. Addition of the supplemental autopsy data set and 3 test cases, which comprised a total of 82 patients and autopsies for both the A16 and FR01 studies, resulted in improved specificity and comparable overall accuracy. Among the 156 enrolled participants, 14 (9%) experienced at least 1 treatment-emergent adverse event. CONCL...

In vivo imaging of brain β-amyloid, a hallmark of Alzheimer disease, may assist in the clinical assessment of suspected Alzheimer disease. OBJECTIVE To determine the sensitivity and specificity of positron emission tomography imaging with flutemetamol injection labeled with radioactive fluorine 18 to detect β-amyloid in the brain using neuropathologically determined neuritic plaque levels as the standard of truth. DESIGN, SETTING, AND PARTICIPANTS Open-label multicenter imaging study that took place at dementia clinics, memory centers, and hospice centers in the United States and England from June 22, 2010, to November 23, 2011. Participants included terminally ill patients who were 55 years or older with a life expectancy of less than 1 year. INTERVENTIONS Flutemetamol injection labeled with radioactive fluorine 18 (Vizamyl; GE Healthcare) administration followed by positron emission tomography imaging and subsequent brain donation. MAIN OUTCOMES AND MEASURES Sensitivity and specificity of flutemetamol injection labeled with radioactive fluorine 18 positron emission tomography imaging for brain β-amyloid. Images were reviewed without and with computed tomography scans and classified as positive or negative for β-amyloid by 5 readers who were blind to patient information. In patients who died, neuropathologically determined neuritic plaque levels were used to confirm scan interpretations and determine sensitivity and specificity. RESULTS Of 176 patients with evaluable images, 68 patients (38%) died during the study, were autopsied, and had neuritic plaque levels determined; 25 brains (37%) were β-amyloid negative; and 43 brains (63%) were β-amyloid positive. Imaging was performed a mean of 3.5 months (range, 0 to 13 months) before death. Sensitivity without computed tomography was 81% to 93% (median, 88%). Median specificity was 88%, with 4 of 5 of the readers having specificity greater than 80%. When scans were interpreted with computed tomography images, sensitivity and specificity improved for most readers but the differences were not significant. The area under the receiver operating curve was 0.90. There were no clinically meaningful findings in safety parameters. CONCLUSIONS AND RELEVANCE This study showed that flutemetamol injection labeled with radioactive fluorine 18 was safe and had high sensitivity and specificity in an end-of-life population. In vivo detection of brain β-amyloid plaque density may increase diagnostic accuracy in cognitively impaired patients.

Purpose Dabrafenib is a selective inhibitor of V600-mutant BRAF kinase, which recently demonstrated improved progression free survival (PFS) as compared with dacarbazine, in metastatic melanoma patients. The current study examined potential genetic markers associated with response and PFS in the phase I study of dabrafenib. Experimental Design Baseline (pre-treatment or archival) melanoma samples were evaluated in 41 patients using a custom genotyping melanoma-specific assay, sequencing of PTEN, and copy number analysis using multiplex ligation amplification and array based comparative genomic hybridization. Nine patients had on-treatment and/or progression samples available. Results All baseline patient samples had BRAFV600E/K confirmed. Baseline PTEN loss/mutation was not associated with best overall response (BOR) to dabrafenib, but it showed a trend for shorter median progression free survival (PFS) (18.3 [95% confidence interval (CI) 9.1–24.3] vs. 32.1 weeks [95% CI 24.1–33], p=0.059). Higher copy number of CCND1 (p=0.009) and lower copy number of CDKN2A (p=0.012) at baseline were significantly associated with decreased PFS. Although no melanomas had high level amplification of BRAF, the two patients with progressive disease as their best response had BRAF copy gain in their tumors. Conclusions Copy number changes in CDKN2A, CCND1, and mutation/copy number changes in PTEN correlated with the duration of PFS in patients treated with dabrafenib. The results suggest that these markers should be considered in the design and interpretation of future trials with selective BRAF inhibitors in advanced melanoma patients.