Single-Agent Divarasib (GDC-6036) in Solid Tumors with a KRAS G12C Mutation.

BACKGROUND: Divarasib (GDC-6036) is a covalent KRAS G12C inhibitor that was designed to have high potency and selectivity. METHODS: In a phase 1 study, we evaluated divarasib administered orally once daily (at doses ranging from 50 to 400 mg) in patients who had advanced or metastatic solid tumors that harbor a KRAS G12C mutation. The primary objective was an assessment of safety; pharmacokinetics, investigator-evaluated antitumor activity, and biomarkers of response and resistance were also assessed. RESULTS: A total of 137 patients (60 with non-small-cell lung cancer [NSCLC], 55 with colorectal cancer, and 22 with other solid tumors) received divarasib. No dose-limiting toxic effects or treatment-related deaths were reported. Treatment-related adverse events occurred in 127 patients (93%); grade 3 events occurred in 15 patients (11%) and a grade 4 event in 1 patient (1%). Treatment-related adverse events resulted in a dose reduction in 19 patients (14%) and discontinuation of treatment in 4 patients (3%). Among patients with NSCLC, a confirmed response was observed in 53.4% of patients (95% confidence interval [CI], 39.9 to 66.7), and the median progression-free survival was 13.1 months (95% CI, 8.8 to could not be estimated). Among patients with colorectal cancer, a confirmed response was observed in 29.1% of patients (95% CI, 17.6 to 42.9), and the median progression-free survival was 5.6 months (95% CI, 4.1 to 8.2). Responses were also observed in patients with other solid tumors. Serial assessment of circulating tumor DNA showed declines in KRAS G12C variant allele frequency associated with response and identified genomic alterations that may confer resistance to divarasib. CONCLUSIONS: Treatment with divarasib resulted in durable clinical responses across KRAS G12C-positive tumors, with mostly low-grade adverse events. (Funded by Genentech; ClinicalTrials.gov number, NCT04449874.).

CXCR2 antagonist navarixin in combination with pembrolizumab in select advanced solid tumors: a phase 2 randomized trial.

C-X-C motif chemokine receptor 2 (CXCR2) has a role in tumor progression, lineage plasticity, and reduction of immune checkpoint inhibitor efficacy. Preclinical evidence suggests potential benefit of CXCR2 inhibition in multiple solid tumors. In this phase 2 study (NCT03473925), adults with previously treated advanced or metastatic castration-resistant prostate cancer (CRPC), microsatellite-stable colorectal cancer (MSS CRC), or non-small-cell lung cancer (NSCLC) were randomized 1:1 to the CXCR2 antagonist navarixin 30 or 100 mg orally once daily plus pembrolizumab 200 mg intravenously every 3 weeks up to 35 cycles. Primary endpoints were investigator-assessed objective response rate (RECIST v1.1) and safety. Of 105 patients (CRPC, n=40; MSS CRC, n=40; NSCLC, n=25), 3 had a partial response (2 CRPC, 1 MSS CRC) for ORRs of 5%, 2.5%, and 0%, respectively. Median progression-free survival was 1.8-2.4 months without evidence of a dose-response relationship, and the study was closed at a prespecified interim analysis for lack of efficacy. Dose-limiting toxicities occurred in 2/48 patients (4%) receiving navarixin 30 mg and 3/48 (6%) receiving navarixin 100 mg; events included grade 4 neutropenia and grade 3 transaminase elevation, hepatitis, and pneumonitis. Treatment-related adverse events occurred in 70/105 patients (67%) and led to treatment discontinuation in 7/105 (7%). Maximal reductions from baseline in absolute neutrophil count were 44.5%-48.2% (cycle 1) and 37.5%-44.2% (cycle 2) and occurred within 6-12 hours postdose in both groups. Navarixin plus pembrolizumab did not demonstrate sufficient efficacy in this study. Safety and tolerability of the combination were manageable. (Trial registration: ClinicalTrials.gov , NCT03473925).

Pembrolizumab plus epacadostat in patients with recurrent/metastatic head and neck squamous cell carcinoma (KEYNOTE-669/ECHO-304): a phase 3, randomized, open-label study.

BACKGROUND: Advanced head and neck squamous cell carcinoma (HNSCC) has a poor prognosis, and new treatment options are needed. Combining immunotherapies with differing mechanisms of action may enhance clinical benefits compared with single-agent immunotherapy. Epacadostat, an indoleamine 2,3 dioxygenase 1 inhibitor, plus pembrolizumab, a PD-1 inhibitor, showed promising activity in advanced HNSCC in the phase 1/2 KEYNOTE-037/ECHO-202 trial. METHODS: KEYNOTE-669/ECHO-304 is a randomized, open-label, phase 3 study evaluating the efficacy and safety of pembrolizumab plus epacadostat, pembrolizumab monotherapy, and the EXTREME regimen (cetuximab with a platinum [carboplatin or cisplatin] and 5-fluorouracil) in recurrent/metastatic (R/M) HNSCC. Participants had no prior systemic therapy for R/M HNSCC and were randomly assigned (2:1:2) to pembrolizumab 200 mg intravenously every 3 weeks plus epacadostat 100 mg orally twice daily, pembrolizumab monotherapy, or EXTREME. The primary endpoint was objective response rate (ORR; investigator assessment). Secondary endpoints were safety and tolerability. Change in serum kynurenine was an exploratory endpoint. Study enrollment was discontinued early as a strategic decision on May 2, 2018, and response assessment was discontinued after first on-study imaging assessment at week 9. Data cut-off was January 17, 2019. RESULTS: Between December 1, 2017, and May 2, 2018, 89 patients were randomly allocated to pembrolizumab plus epacadostat (n = 35), pembrolizumab monotherapy (n = 19), or EXTREME (n = 35). ORR (95% CI) was 31% (17%-49%) for pembrolizumab plus epacadostat, 21% (6%-46%) for pembrolizumab monotherapy, and 34% (19%-52%) for EXTREME. Treatment-related adverse events (TRAEs) occurred in 82% (n = 28) of patients receiving pembrolizumab plus epacadostat, 63% (n = 12) receiving pembrolizumab monotherapy, and 100% (n = 34) receiving EXTREME. Grade 3-4 TRAEs occurred in 24% (n = 8) of patients receiving pembrolizumab plus epacadostat, 16% (n = 3) receiving pembrolizumab monotherapy, and 82% (n = 28) receiving EXTREME. No deaths occurred due to AEs. Pembrolizumab plus epacadostat treatment reduced kynurenine levels but not to that of healthy subjects. CONCLUSIONS: Pembrolizumab plus epacadostat and pembrolizumab monotherapy provided a similar response rate to EXTREME and demonstrated a manageable safety profile in patients with R/M HNSCC. TRIAL REGISTRATION: NCT03358472. Date of trial registration: November 30, 2017.

Efficacy and safety of pembrolizumab monotherapy in patients with advanced thyroid cancer in the phase 2 KEYNOTE-158 study.

BACKGROUND: The authors report results from the thyroid carcinoma cohort of the multicohort phase 2 KEYNOTE-158 study (NCT02628067), which evaluated pembrolizumab monotherapy in patients with previously treated cancers. METHODS: Eligible patients had histologically and/or cytologically confirmed papillary or follicular thyroid carcinoma, failure of or intolerance to prior therapy, and measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST) v1.1. Patients received pembrolizumab (200 mg) every 3 weeks for up to 35 cycles. The primary end point was objective response rate (ORR) per RECIST v1.1 by independent central review. RESULTS: A total of 103 patients were enrolled and received pembrolizumab. Median duration from first dose to data cutoff (October 5, 2020) was 49.4 (range, 43.9-54.9) months. ORR was 6.8% (95% confidence interval [CI], 2.8%-13.5%), and median duration of response was 18.4 (range, 4.2-47.2+) months. ORR was 8.7% (95% CI, 2.4%-20.8%) among patients with programmed cell death ligand 1 (PD-L1) combined positive score (CPS) ≥1 (n = 46) and 5.7% (95% CI, 1.2%-15.7%) among patients with PD-L1 CPS <1 (n = 53). Median overall survival and progression-free survival were 34.5 (95% CI, 21.2 to not reached) and 4.2 (95% CI, 3.9-6.2) months, respectively. Treatment-related adverse events occurred in 69.9% of patients (grade 3-5, 14.6%). CONCLUSIONS: Pembrolizumab demonstrated manageable toxicity and durable antitumor activity in a small subset of patients with advanced thyroid cancer. These results provide evidence of modest antitumor activity in this setting regardless of tumor PD-L1 expression. Future studies evaluating immune checkpoint inhibitors in patients with differentiated thyroid cancer should focus on biomarker-driven patient selection or combination of immune checkpoint inhibitors with other agents, in order to achieve higher response rates than observed in this study.

Patient and provider factors associated with colorectal cancer screening among average risk health plan enrollees in the US, 2015-2018.

BACKGROUND: To assess patient and primary care provider (PCP) factors associated with adherence to American Cancer Society (ACS) and United States Preventive Services Task Force (USPSTF) guidelines for average risk colorectal cancer (CRC) screening. METHODS: Retrospective case-control study of medical and pharmacy claims from the Optum Research Database from 01/01/2014 - 12/31/2018. Enrollee sample was adults aged 50 - 75 years with ≥ 24 months continuous health plan enrollment. Provider sample was PCPs listed on the claims of average-risk patients in the enrollee sample. Enrollee-level screening opportunities were based on their exposure to the healthcare system during the baseline year. Screening adherence, calculated at the PCP level, was the percent of average-risk patients up to date with screening recommendations each year. Logistic regression modelling was used to examine the association between receipt of screening and enrollee and PCP characteristics. An ordinary least squares model was used to determine the association between screening adherence among the PCP's panel of patients and patient characteristics. RESULTS: Among patients with a PCP, adherence to ACS and USPSTF screening guidelines ranged from 69 to 80% depending on PCP specialty and type. The greatest enrollee-level predictors for CRC screening were having a primary/preventive care visit (OR = 4.47, p < 0.001) and a main PCP (OR = 2.69, p < 0.001). CONCLUSIONS: Increased access to preventive/primary care visits could improve CRC screening rates; however, interventions not dependent on healthcare system contact, such as home-based screening, may circumvent the dependence on primary care visits to complete CRC screening.

Predicted long-term impact of COVID-19 pandemic-related care delays on cancer mortality in Canada.

The COVID-19 pandemic has affected cancer care worldwide. This study aimed to estimate the long-term impacts of cancer care disruptions on cancer mortality in Canada using a microsimulation model. The model simulates cancer incidence and survival using cancer incidence, stage at diagnosis and survival data from the Canadian Cancer Registry. We modeled reported declines in cancer diagnoses and treatments recorded in provincial administrative datasets in March 2020 to June 2021. Based on the literature, we assumed that diagnostic and treatment delays lead to a 6% higher rate of cancer death per 4-week delay. After June 2021, we assessed scenarios where cancer treatment capacity returned to prepandemic levels, or to 10% higher or lower than prepandemic levels. Results are the median predictions of 10 stochastic simulations. The model predicts that cancer care disruptions during the COVID-19 pandemic could lead to 21 247 (2.0%) more cancer deaths in Canada in 2020 to 2030, assuming treatment capacity is recovered to 2019 prepandemic levels in 2021. This represents 355 172 life years lost expected due to pandemic-related diagnostic and treatment delays. The largest number of expected excess cancer deaths was predicted for breast, lung and colorectal cancers, and in the provinces of Ontario, Québec and British Columbia. Diagnostic and treatment capacity in 2021 onward highly influenced the number of cancer deaths over the next decade. Cancer care disruptions during the COVID-19 pandemic could lead to significant life loss; however, most of these could be mitigated by increasing diagnostic and treatment capacity in the short-term to address the service backlog.

Avelumab plus Axitinib versus Sunitinib for Advanced Renal-Cell Carcinoma.

BACKGROUND: In a single-group, phase 1b trial, avelumab plus axitinib resulted in objective responses in patients with advanced renal-cell carcinoma. This phase 3 trial involving previously untreated patients with advanced renal-cell carcinoma compared avelumab plus axitinib with the standard-of-care sunitinib. METHODS: We randomly assigned patients in a 1:1 ratio to receive avelumab (10 mg per kilogram of body weight) intravenously every 2 weeks plus axitinib (5 mg) orally twice daily or sunitinib (50 mg) orally once daily for 4 weeks (6-week cycle). The two independent primary end points were progression-free survival and overall survival among patients with programmed death ligand 1 (PD-L1)-positive tumors. A key secondary end point was progression-free survival in the overall population; other end points included objective response and safety. RESULTS: A total of 886 patients were assigned to receive avelumab plus axitinib (442 patients) or sunitinib (444 patients). Among the 560 patients with PD-L1-positive tumors (63.2%), the median progression-free survival was 13.8 months with avelumab plus axitinib, as compared with 7.2 months with sunitinib (hazard ratio for disease progression or death, 0.61; 95% confidence interval [CI], 0.47 to 0.79; P<0.001); in the overall population, the median progression-free survival was 13.8 months, as compared with 8.4 months (hazard ratio, 0.69; 95% CI, 0.56 to 0.84; P<0.001). Among the patients with PD-L1-positive tumors, the objective response rate was 55.2% with avelumab plus axitinib and 25.5% with sunitinib; at a median follow-up for overall survival of 11.6 months and 10.7 months in the two groups, 37 patients and 44 patients had died, respectively. Adverse events during treatment occurred in 99.5% of patients in the avelumab-plus-axitinib group and in 99.3% of patients in the sunitinib group; these events were grade 3 or higher in 71.2% and 71.5% of the patients in the respective groups. CONCLUSIONS: Progression-free survival was significantly longer with avelumab plus axitinib than with sunitinib among patients who received these agents as first-line treatment for advanced renal-cell carcinoma. (Funded by Pfizer and Merck [Darmstadt, Germany]; JAVELIN Renal 101 ClinicalTrials.gov number, NCT02684006.).

Assessing the Effects of Geniculate Artery Embolization in a Nonsurgical Animal Model of Osteoarthritis.

PURPOSE: To create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE). MATERIALS AND METHODS: Fluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4-6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4-6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75-250-µm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest. RESULTS: The mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed. CONCLUSIONS: A nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.

Adherence to fecal immunochemical test screening among adults at average risk for colorectal cancer.

PURPOSE: This study examined adherence to screening for fecal immunochemical test (FIT). METHODS: Adults (≥ 50-75) with a FIT between 1/1/2014 and 6/30/2019 in MarketScan administrative claims were selected (index = earliest FIT). Patients were followed for 10 years pre- and 3 years post-index. Patients at increased risk for CRC or with prior screening were excluded. Year over year adherence was measured post-index. RESULTS: Of 10,253 patients, the proportion adherent to repeat testing at year 2 was 23.4% and 10.6% at year 3. Of 76.6% not adherent in year 2, 5.4% were adherent in year 3. CONCLUSION: Results suggest adherence to FIT tests is poor, minimizing potential benefits. Future studies are needed to consider alternative test options and whether more choice will improve long-term adherence.

Analysis of Geographic and Environmental Factors and Their Association with Cutaneous Melanoma Incidence in Canada.

BACKGROUND: Over 90% of skin cancers including cutaneous melanoma (CM) are related directly to sun exposure. Despite extensive knowledge on ultraviolet radiation's (UVR) detrimental impact, many still fail to implement sun protection/sun avoidance. Human behavior, attitudes, and cultural norms of individuals and communities heavily depend on the surrounding climate/environment. In many instances, the climate shapes the culture/norms of the society. Canada has vast geographic/environmental differences. METHODS: In the current ecological study, we sought to examine the relationship between various geographic and environmental factors and the distribution of CM incidence by Forward Sortation Area (FSA) postal code across Canada. CM incidence data were extracted from the Canadian Cancer Registry, while environmental data were extracted from the Canadian Urban Environmental Health Research Consortium (greenspace, as measured by the normalized difference vegetation index; annual highest temperature; absolute number and average length of yearly heat events; annual total precipitation [rain and snow]; absolute number and average length of events with precipitation [rain and snow]; and summer UVR index). The above geographic/environmental data by FSA were correlated with the respective CM incidence employing negative binomial regression model. RESULTS: Our analysis highlights that increases in annual average temperature, summer UVR, and greenspace were associated with higher expected incidence of CM cases, while higher number of annual heat events together with highest annual temperature and higher average number of annual rain events were associated with a decrease in CM incidence rate. This study also highlights regional variation in environmental CM risk factors in Canada. CONCLUSIONS: This national population-based study presents clinically relevant conclusions on weather/geographic variations associated with CM incidence in Canada and will help refine targeted CM prevention campaigns by understanding unique weather/geographic variations in high-risk regions.

Incident colorectal cancer screening and associated healthcare resource utilization and Medicare cost among Medicare beneficiaries aged 66-75 years in 2016-2018.

BACKGROUND: While prevalence of up-to-date screening status is the usual reported statistic, annual screening incidence may better reflect current clinical practices and is more actionable. Our main purpose was to examine incident colorectal cancer (CRC) screening rates in Medicare beneficiaries and to explore characteristics associated with CRC screening. METHODS: Using 20% Medicare random sample data, the study population included 2016-2018 Medicare fee-for-service beneficiaries covered by Parts A and B aged 66-75 years at average CRC risk. For each study year, we excluded individuals who had a Medicare claim for a colonoscopy within 9 years, flexible sigmoidoscopy within 4 years, and multitarget stool DNA test (mt-sDNA) within 2 years prior; therefore, any observed screening during study year was considered an "incident screening". Incident screening rates were calculated as number of incident screenings per 1000 Medicare beneficiaries. Overall rates were normalized to 2018 Medicare population distributions of age, sex, and race. RESULTS: Each year, > 1.4 million individuals met the inclusion/exclusion criteria from > 6.5 million Medicare beneficiaries. The overall adjusted incident CRC screening rate per 1000 Medicare beneficiaries increased from 85.2 in 2016 to 94.3 in 2018. Incident screening rates decreased 11.4% (22.9 to 20.3) for colonoscopy and 2.4% (58.3 to 56.9) for fecal immunochemical test/guaiac-based fecal occult blood test; they increased 201.5% (6.5 to 19.6) for mt-sDNA. The 2018 unadjusted rate was 76.0 for men and 110.4 for women. By race/ethnicity, the highest 2018 rate was for Asian individuals and the lowest rate was for Black individuals (113.4 and 72.8, respectively). CONCLUSIONS: The 2016-2018 observed incident CRC screening rate in average-risk Medicare beneficiaries, while increasing, was still low. Our findings suggest more work is needed to improve CRC screening overall and, especially, among male and Black Medicare beneficiaries.

A Non-Hazardous Deparaffinization Protocol Enables Quantitative Proteomics of Core Needle Biopsy-Sized Formalin-Fixed and Paraffin-Embedded (FFPE) Tissue Specimens.

Most human tumor tissues that are obtained for pathology and diagnostic purposes are formalin-fixed and paraffin-embedded (FFPE). To perform quantitative proteomics of FFPE samples, paraffin has to be removed and formalin-induced crosslinks have to be reversed prior to proteolytic digestion. A central component of almost all deparaffinization protocols is xylene, a toxic and highly flammable solvent that has been reported to negatively affect protein extraction and quantitative proteome analysis. Here, we present a 'green' xylene-free protocol for accelerated sample preparation of FFPE tissues based on paraffin-removal with hot water. Combined with tissue homogenization using disposable micropestles and a modified protein aggregation capture (PAC) digestion protocol, our workflow enables streamlined and reproducible quantitative proteomic profiling of FFPE tissue. Label-free quantitation of FFPE cores from human ductal breast carcinoma in situ (DCIS) xenografts with a volume of only 0.79 mm3 showed a high correlation between replicates (r2 = 0.992) with a median %CV of 16.9%. Importantly, this small volume is already compatible with tissue micro array (TMA) cores and core needle biopsies, while our results and its ease-of-use indicate that further downsizing is feasible. Finally, our FFPE workflow does not require costly equipment and can be established in every standard clinical laboratory.

Phase I study of daily and weekly regimens of the orally administered MDM2 antagonist idasanutlin in patients with advanced tumors.

Aim The oral MDM2 antagonist idasanutlin inhibits the p53-MDM2 interaction, enabling p53 activation, tumor growth inhibition, and increased survival in xenograft models. Methods We conducted a Phase I study of idasanutlin (microprecipitate bulk powder formulation) to determine the maximum tolerated dose (MTD), safety, pharmacokinetics, pharmacodynamics, food effect, and clinical activity in patients with advanced malignancies. Schedules investigated were once weekly for 3 weeks (QW × 3), once daily for 3 days (QD × 3), or QD × 5 every 28 days. We also analyzed p53 activation and the anti-proliferative effects of idasanutlin. Results The dose-escalation phase included 85 patients (QW × 3, n = 36; QD × 3, n = 15; QD × 5, n = 34). Daily MTD was 3200 mg (QW × 3), 1000 mg (QD × 3), and 500 mg (QD × 5). Most common adverse events were diarrhea, nausea/vomiting, decreased appetite, and thrombocytopenia. Dose-limiting toxicities were nausea/vomiting and myelosuppression; myelosuppression was more frequent with QD dosing and associated with pharmacokinetic exposure. Idasanutlin exposure was approximately dose proportional at low doses, but less than dose proportional at > 600 mg. Although inter-patient variability in exposure was high with all regimens, cumulative idasanutlin exposure over the whole 28-day cycle was greatest with a QD × 5 regimen. No major food effect on pharmacokinetic exposure occurred. MIC-1 levels were higher with QD dosing, increasing in an exposure-dependent manner. Best response was stable disease in 30.6% of patients, prolonged (> 600 days) in 2 patients with sarcoma. Conclusions Idasanutlin demonstrated dose- and schedule-dependent p53 activation with durable disease stabilization in some patients. Based on these findings, the QD × 5 schedule was selected for further development. TRIAL REGISTRATION: NCT01462175 (ClinicalTrials.gov), October 31, 2011.

Cross-sectional adherence with the multi-target stool DNA test for colorectal cancer screening in a large, nationally insured cohort.

PURPOSE: Colorectal cancer (CRC) is the second most deadly cancer in the USA. Early detection can improve CRC outcomes, but recent national screening rates (62%) remain below the 80% goal set by the National Colorectal Cancer Roundtable. Multiple options are endorsed for average-risk CRC screening, including the multi-target stool DNA (mt-sDNA) test. We evaluated cross-sectional mt-sDNA test completion in a population of commercially and Medicare-insured patients. METHODS: Participants included individuals ages 50 years and older with commercial insurance or Medicare, with a valid mt-sDNA test shipped by Exact Sciences Laboratories LLC between January 1, 2018, and December 31, 2018 (n = 1,420,460). In 2020, we analyzed cross-sectional adherence, as the percent of successfully completed tests within 365 days of shipment date. RESULTS: Overall cross-sectional adherence was 66.8%. Adherence was 72.1% in participants with Traditional Medicare, 69.1% in participants with Medicare Advantage, and 61.9% in participants with commercial insurance. Adherence increased with age: 60.8% for ages 50-64, 71.3% for ages 65-75, and 74.7% for ages 76 + years. Participants with mt-sDNA tests ordered by gastroenterologists had a higher adherence rate (78.3%) than those with orders by primary care clinicians (67.2%). Geographically, adherence rates were highest among highly rural patients (70.8%) and ordering providers in the Pacific region (71.4%). CONCLUSIONS: Data from this large, national sample of insured patients demonstrate high cross-sectional adherence with the mt-sDNA test, supporting its role as an accepted, noninvasive option for average-risk CRC screening. Attributes of mt-sDNA screening, including home-based convenience and accompanying navigation support, likely contributed to high completion rates.

Translational control in the tumor microenvironment promotes lung metastasis: Phosphorylation of eIF4E in neutrophils.

The translation of mRNAs into proteins serves as a critical regulatory event in gene expression. In the context of cancer, deregulated translation is a hallmark of transformation, promoting the proliferation, survival, and metastatic capabilities of cancer cells. The best-studied factor involved in the translational control of cancer is the eukaryotic translation initiation factor 4E (eIF4E). We and others have shown that eIF4E availability and phosphorylation promote metastasis in mouse models of breast cancer by selectively augmenting the translation of mRNAs involved in invasion and metastasis. However, the impact of translational control in cell types within the tumor microenvironment (TME) is unknown. Here, we demonstrate that regulatory events affecting translation in cells of the TME impact cancer progression. Mice bearing a mutation in the phosphorylation site of eIF4E (S209A) in cells comprising the TME are resistant to the formation of lung metastases in a syngeneic mammary tumor model. This is associated with reduced survival of prometastatic neutrophils due to decreased expression of the antiapoptotic proteins BCL2 and MCL1. Furthermore, we demonstrate that pharmacological inhibition of eIF4E phosphorylation prevents metastatic progression in vivo, supporting the development of phosphorylation inhibitors for clinical use.

Association of tumour mutational burden with outcomes in patients with advanced solid tumours treated with pembrolizumab: prospective biomarker analysis of the multicohort, open-label, phase 2 KEYNOTE-158 study.

BACKGROUND: Tumour mutational burden (TMB) has been retrospectively correlated with response to immune checkpoint blockade. We prospectively explored the association of high tissue TMB (tTMB-high) with outcomes in ten tumour-type-specific cohorts from the phase 2 KEYNOTE-158 study, which assessed the anti-PD-1 monoclonal antibody pembrolizumab in patients with selected, previously treated, advanced solid tumours. METHODS: In the multi-cohort, open-label, non-randomised, phase 2 KEYNOTE-158 study, patients were enrolled from 81 academic facilities and community-based institutions across 21 countries in Africa, the Americas, Asia, and Europe. Eligible patients were aged 18 years or older, had a histologically or cytologically confirmed advanced (ie, unresectable or metastatic, or both) incurable solid tumour (eligible tumour types were anal, biliary, cervical, endometrial, mesothelioma, neuroendocrine, salivary, small-cell lung, thyroid, and vulvar), progression on or intolerance to one or more lines of standard therapy, had measurable disease per Response Evaluation Criteria in Solid Tumors (RECIST; version 1.1) assessed by independent central radiological review, Eastern Cooperative Oncology Group performance status of 0 or 1, life expectancy of at least 3 months, adequate organ function, and a tumour sample for biomarker analysis. Participants were given pembrolizumab 200 mg intravenously every 3 weeks for up to 35 cycles. Tissue TMB (tTMB) was assessed in formalin-fixed paraffin-embedded tumour samples using the FoundationOne CDx assay (Foundation Medicine, Cambridge, MA, USA). The prespecified definition of tTMB-high status was at least 10 mutations per megabase. The primary endpoint was the proportion of patients with an objective response (complete or partial response) as per Response Evaluation Criteria in Solid Tumours (version 1.1) by independent central review. This prespecified analysis assessed the association between antitumour activity and tTMB in treated patients with evaluable tTMB data. Efficacy was assessed in all participants who received at least one dose of pembrolizumab, had evaluable tTMB data, and were enrolled at least 26 weeks before data cutoff (June 27, 2019), and safety was assessed in all participants who received at least one dose of pembrolizumab and had tTMB-high status. KEYNOTE-158 is registered at ClinicalTrials.gov, NCT02628067, and is ongoing. FINDINGS: Between Jan 15, 2016, and June 25, 2019, 1073 patients were enrolled. 1066 participants were treated as of data cutoff (June 27, 2019), of whom 805 (76%) were evaluable for TMB, and 105 (13%) of 805 had tTMB-high status and were assessed for safety. 1050 (98%) of 1066 patients enrolled by at least 26 weeks before data cutoff, of whom 790 (75%) were evaluable for TMB and included in efficacy analyses. 102 (13%) of these 790 patients had tTMB-high status (≥10 mutations per megabase), and 688 (87%) patients had non-tTMB-high status (<10 mutations per megabase). Median study follow-up was 37·1 months (IQR 35·0-38·3). Objective responses were observed in 30 (29%; 95% CI 21-39) of 102 patients in the tTMB-high group and 43 (6%; 5-8) of 688 in the non-tTMB-high group. 11 (10%) of 105 patients had treatment-related serious adverse events. 16 (15%) participants had a grade 3-5 treatment-related adverse event, of which colitis was the only such adverse event that occurred in more than one patient (n=2). One patient had fatal pneumonia that was assessed by the investigator to be treatment related. INTERPRETATION: tTMB-high status identifies a subgroup of patients who could have a robust tumour response to pembrolizumab monotherapy. tTMB could be a novel and useful predictive biomarker for response to pembrolizumab monotherapy in patients with previously treated recurrent or metastatic advanced solid tumours. FUNDING: Merck Sharp & Dohme Corp, a subsidiary of Merck & Co, Inc.

A phase 1 study of the MDM2 antagonist RO6839921, a pegylated prodrug of idasanutlin, in patients with advanced solid tumors.

Purpose MDM2 is a negative regulator of the tumor suppressor p53. RO6839921 is an inactive pegylated prodrug of idasanutlin, an MDM2 antagonist, developed for intravenous administration. On cleavage by plasma esterases, the active principle (AP = idasanutlin) is released. This phase 1 study investigated the safety, pharmacokinetics, and pharmacodynamics of RO6839921 in patients with advanced solid tumors (NCT02098967). Methods Patients were evaluated on a 5-day dosing schedule every 28 days. Dose escalation used the Bayesian new continual reassessment model. Accelerated dose titration was permitted until grade ≥2 drug-related AEs were observed. The target DLT rate to define the MTD was 16-25%. p53 activation was assessed by measuring macrophage inhibitory cytokine-1 (MIC-1). Results Forty-one patients received 14-120 mg AP; 39 were DLT evaluable. The MTD was 110-mg AP (8% DLT rate), whereas 120-mg AP had a 44% DLT rate. DLTs were neutropenia, thrombocytopenia, and stridor. The most common treatment-related AEs (≥30%) were nausea, fatigue, vomiting, and thrombocytopenia. Pharmacokinetic analyses indicated rapid conversion of prodrug to AP and an approximately linear and dose-proportional dose-exposure relationship, with a 2-fold increase in exposure between Days 1 and 5 of AP. MIC-1 increases were exposure dependent. Stable disease was observed in 14 patients (34%). Conclusions RO6839921 showed reduced pharmacokinetic exposure variability and a safety profile comparable with that of oral idasanutlin. Although this study indicated that RO6839921 could be administered to patients, the results did not provide sufficient differentiation or improvement in the biologic or safety profile compared with oral idasanutlin to support continued development.

The sonic hedgehog factor GLI1 imparts drug resistance through inducible glucuronidation.

Drug resistance is a major hurdle in oncology. Responses of acute myeloid leukaemia (AML) patients to cytarabine (Ara-C)-based therapies are often short lived with a median overall survival of months. Therapies are under development to improve outcomes and include targeting the eukaryotic translation initiation factor (eIF4E) with its inhibitor ribavirin. In a Phase II clinical trial in poor prognosis AML, ribavirin monotherapy yielded promising responses including remissions; however, all patients relapsed. Here we identify a novel form of drug resistance to ribavirin and Ara-C. We observe that the sonic hedgehog transcription factor glioma-associated protein 1 (GLI1) and the UDP glucuronosyltransferase (UGT1A) family of enzymes are elevated in resistant cells. UGT1As add glucuronic acid to many drugs, modifying their activity in diverse tissues. GLI1 alone is sufficient to drive UGT1A-dependent glucuronidation of ribavirin and Ara-C, and thus drug resistance. Resistance is overcome by genetic or pharmacological inhibition of GLI1, revealing a potential strategy to overcome drug resistance in some patients.

The MNK1/2-eIF4E Axis as a Potential Therapeutic Target in Melanoma.

: Melanoma is a type of skin cancer that originates in the pigment-producing cells of the body known as melanocytes. Most genetic aberrations in melanoma result in hyperactivation of the mitogen activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) pathways. We and others have shown that a specific protein synthesis pathway known as the MNK1/2-eIF4E axis is often dysregulated in cancer. The MNK1/2-eIF4E axis is a point of convergence for these signaling pathways that are commonly constitutively activated in melanoma. In this review we consider the functional implications of aberrant mRNA translation in melanoma and other malignancies. Moreover, we discuss the consequences of inhibiting the MNK1/2-eIF4E axis on the tumor and tumor-associated cells, and we provide important avenues for the utilization of this treatment modality in combination with other targeted and immune-based therapies. The past decade has seen the increased development of selective inhibitors to block the action of the MNK1/2-eIF4E pathway, which are predicted to be an effective therapy regardless of the melanoma subtype (e.g., cutaneous, acral, and mucosal).