No abstract

Tumors harboring one of the new RAS mutations are unlikely to significantly benefit from anti-EGFR mAb therapy in mCRC.

IMPORTANCE High body mass index (BMI) is independently associated with overall survival benefit from immune checkpoint inhibitor therapy in patients with melanoma, yet whether BMI is associated with outcomes in patients with advanced non-small cell lung cancer treated with atezolizumab remains unknown.OBJECTIVE To examine whether BMI is associated with survival outcomes and adverse events in patients with non-small cell lung cancer (NSCLC) treated with atezolizumab. DESIGN, SETTING, AND PARTICIPANTSA pooled analysis of individual patient-level data from 4 international, multicenter clinical trials was performed. Two were single-arm phase 2 trials (BIRCH [data cutoff of May 28, 2015] and FIR [data cutoff of January 7, 2015]), and 2 were 2-arm randomized clinical trials (POPLAR [phase 2; data cutoff of May 8, 2015] and OAK [phase 3; data cutoff of July 7, 2016]). Patients with advanced NSCLC previously untreated or treated with at least 1 line of systemic therapy, with measurable disease and good organ function and without contraindications for chemotherapy or immune checkpoint inhibitor therapy, were included in these trials. Data analyses were performed from February 28, 2019, to September 30, 2019. INTERVENTIONSThe control group was treated with docetaxel once every 3 weeks until disease progression or unacceptable toxic effects occurred in POPLAR and OAK. The experimental group was treated with atezolizumab once every 3 weeks until disease progression or unacceptable toxic effects occurred in all available trials. MAIN OUTCOMES AND MEASURESAssociation between BMI and overall survival (OS), progression-free survival (PFS), and treatment-related adverse events. Intention-to-treat analysis was conducted. RESULTS Adequate data were available for 2110 patients from a total pool of 2261 across 4 trials. Of those 2110, 1434 patients (median age, 64 years [range, 57-70 years]; 890 men [62%]) received atezolizumab and 676 patients (median age, 63 years[range, 57-69 years];419 men [62%]) received docetaxel. There was a linear association between increasing BMI and OS in patients treated with atezolizumab. Obesity (BMI Ն30 [calculated as weight in kilograms divided by height in meters squared]) was associated with significantly improved OS in patients treated with atezolizumab, but not in those who received docetaxel after adjusting for confounding variables. The association between BMI and OS/PFS was the strongest in the high PD-L1 expression subgroup. Overall survival for patients with the highest category of PD-L1 expression (Ն50% of tumor cells or Ն10% of tumor-infiltrating immune cells; n = 436) had hazard ratios of 0.36 (95% CI, 0.21-0.62) for the group with obesity and 0.69 (95% CI, 0.48-0.98) for the group with overweight. Patients with the highest category of PD-L1 expression had PFS hazard ratios of 0.68 (95% CI, 0.49-0.94) for the group with obesity and 0.72 (95% CI, 0.56-0.92) for the group with overweight. Treatment-related adverse events were not associated with BMI. CONCLUSIONS AND RELEVANCEHigh BMI appea...

Studies were performed to elucidate the mechanism responsible for the reduction in K m values of UDP-glucuronosyltransferase 2B7 (UGT2B7) substrates observed for incubations conducted in the presence of albumin. Addition of bovine serum albumin (BSA) and fatty acid-free human serum albumin (HSA-FAF), but not "crude" HSA, resulted in an approximate 90% reduction in the K m values for the glucuronidation of zidovudine (AZT) by human liver microsomes (HLM) and UGT2B7 and a 50 to 75% reduction in the S 50 for 4-methylumbelliferone (4MU) glucuronidation by UGT2B7, without affecting V max . Oleic, linoleic, and arachidonic acids were shown to be the most abundant unsaturated long-chain fatty acids present in crude HSA and in the membranes of HLM and human embryonic kidney (HEK)293 cells, and it was demonstrated that these and other unsaturated long-chain fatty acids were UGT2B7 substrates.Glucuronides with R f (retention factor) values corresponding to the glucuronides of linoleic and arachidonic acid were detected when HLM and HEK293 cell lysates were incubated with radiolabeled cofactor, and the intensity of the bands was modulated by the presence of crude HSA (increased) and BSA or HSA-FAF (decreased). Oleic, linoleic, and arachidonic acid inhibited AZT and 4MU glucuronidation by HLM and/or UGT2B7, due to an increase in K m /S 50 without a change in V max . Addition of BSA and HSA-FAF reversed the inhibition. Likewise, coexpression of UGT2B7 and HSA in HEK293 cells reduced the K m /S 50 values of these substrates. It is postulated that BSA and HSA-FAF sequester inhibitory fatty acids released during incubations, and the apparent high K m values observed for UGT2B7 substrates arise from the presence of these endogenous inhibitors.

Background:Metastatic colorectal cancer (mCRC) that harbours a BRAF V600E mutation (BRAF MT) is associated with poorer outcomes. However, whether this mutation is predictive of treatment benefit from anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) is uncertain.Methods:We conducted a systematic review and meta-analysis of randomised controlled trials (RCTs) published up to July 2014 that evaluated the effect of BRAF MT on the treatment benefit from anti-EGFR mAbs for mCRC.Results:Seven RCTs met the inclusion criteria for assessment of overall survival (OS), whereas eight RCTs met the inclusion criteria for assessment of progression-free survival (PFS). For RAS WT/BRAF MT tumours, the hazard ratio for OS benefit with anti-EGFR mAbs was 0.97 (95% CI; 0.67–1.41), whereas the hazard ratio was 0.81 (95% CI; 0.70–0.95) for RAS WT/BRAF WT tumours. However, the test of interaction (P=0.43) was not statistically significant, highlighting that the observed differences in the effect of anti-EGFR mAbs on OS according to the BRAF mutation status may be due to chance alone. Regarding PFS benefit with anti-EGFR mAbs, the hazard ratio was 0.86 (95% CI; 0.61–1.21) for RAS WT/BRAF MT tumours as compared with 0.62 (95% CI; 0.50–0.77) for RAS WT/BRAF WT tumours (test of interaction, P=0.07).Interpretation:This meta-analysis demonstrates that there is insufficient evidence to definitively state that RAS WT/BRAF MT individuals attain a different treatment benefit from anti-EGFR mAbs for mCRC compared with RAS WT/BRAF WT individuals. As such, there are insufficient data to justify the exclusion of anti-EGFR mAb therapy for patients with RAS WT/BRAF MT mCRC.