5 research outputs found
First evidence of P21/n to P21/c structural transformation in pyroxene-type LiAlGe2O6 under high-pressure conditions
Abstract
The high-pressure behaviour of the pyroxene-type compound LiAlGe2O6, the unique representative
of a P21/n-pyroxene, was investigated by in-situ X-ray diffraction and Raman spectroscopy on
single-crystal samples hydrostatically pressurized in a diamond-anvil cell. The structure was found
to undergo a first-order phase transition on compression, with a critical transition at 5.23 \ub1 0.02
GPa. Together with a strong volume discontinuity of -DV/V0 = -4.1% the transition shows a
remarkable hysteresis loop over at least 0.70 GPa pressure interval. The bulk modulus of the lowand
high-pressure polymorphs corresponds to K0 = 114(1) and 123(2) GPa, respectively, as
described by a 2nd order Birch-Murnaghan equation of state. Based on the systematic extinctions the
transition was identified as a P21/n-to-P21/c transformation. The mechanism of structural
transformation was identified to be controlled by the stereochemistry of the Li atoms at the M2 site,
which changes its coordination number from 5 to 6. The formation of new Li-O bonds involves the
co-operative folding of Ge2O6-chains, which explains the anisotropy of axial elasticities and the
spontaneous strain across the transformation. Simultaneously the distortion correction of AlO6 units
associated with the transition further explains the preference of the P21/c structure under pressure
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Lenvatinib plus pembrolizumab versus lenvatinib plus placebo for advanced hepatocellular carcinoma (LEAP-002): a randomised, double-blind, phase 3 trial
Summary Background Systemic therapies have improved the management of hepatocellular carcinoma, but there is still a need to further enhance overall survival in first-line advanced stages. This study aimed to evaluate the addition of pembrolizumab to lenvatinib versus lenvatinib plus placebo in the first-line setting for unresectable hepatocellular carcinoma. Methods In this global, randomised, double-blind, phase 3 study (LEAP-002), patients aged 18 years or older with unresectable hepatocellular carcinoma, Child Pugh class A liver disease, an Eastern Cooperative Oncology Group performance status of 0 or 1, and no previous systemic treatment were enrolled at 172 global sites. Patients were randomly assigned (1:1) with a central interactive voice-response system (block size of 4) to receive lenvatinib (bodyweight <60 kg, 8 mg/day; bodyweight ≥60 kg, 12 mg/day) plus pembrolizumab (200 mg every 3 weeks) or lenvatinib plus placebo. Randomisation was stratified by geographical region, macrovascular portal vein invasion or extrahepatic spread or both, α-fetoprotein concentration, and Eastern Cooperative Oncology Group performance status. Dual primary endpoints were overall survival (superiority threshold at final overall survival analysis, one-sided p=0·019; final analysis to occur after 532 events) and progression-free survival (superiority threshold one-sided p=0·002; final analysis to occur after 571 events) in the intention-to-treat population. Results from the final analysis are reported. This study is registered with ClinicalTrials.gov, NCT03713593, and is active but not recruiting. Findings Between Jan 17, 2019, and April 28, 2020, of 1309 patients assessed, 794 were randomly assigned to lenvatinib plus pembrolizumab (n=395) or lenvatinib plus placebo (n=399). Median age was 66·0 years (IQR 57·0–72·0), 644 (81%) of 794 were male, 150 (19%) were female, 345 (43%) were Asian, 345 (43%) were White, 22 (3%) were multiple races, 21 (3%) were American Indian or Alaska Native, 21 (3%) were Native Hawaiian or other Pacific Islander, 13 (2%) were Black or African American, and 46 (6%) did not have available race data. Median follow up as of data cutoff for the final analysis (June 21, 2022) was 32·1 months (IQR 29·4–35·3). Median overall survival was 21·2 months (95% CI 19·0–23·6; 252 [64%] of 395 died) with lenvatinib plus pembrolizumab versus 19·0 months (17·2–21·7; 282 [71%] of 399 died) with lenvatinib plus placebo (hazard ratio [HR] 0·84; 95% CI 0·71–1·00; stratified log-rank p=0·023). As of data cutoff for the progression-free survival final analysis (April 5, 2021), median progression-free survival was 8·2 months (95% CI 6·4–8·4; 270 events occurred [42 deaths; 228 progressions]) with lenvatinib plus pembrolizumab versus 8·0 months (6·3–8·2; 301 events occurred [36 deaths; 265 progressions]) with lenvatinib plus placebo (HR 0·87; 95% CI 0·73–1·02; stratified log-rank p=0·047). The most common treatment-related grade 3–4 adverse events were hypertension (69 [17%] of 395 patients in the lenvatinib plus pembrolizumab group vs 68 [17%] of 395 patients) in the lenvatinib plus placebo group), increased aspartate aminotransferase (27 [7%] vs 17 [4%]), and diarrhoea (25 [6%] vs 15 [4%]). Treatment-related deaths occurred in four (1%) patients in the lenvatinib plus pembrolizumab group (due to gastrointestinal haemorrhage and hepatorenal syndrome [n=1 each] and hepatic encephalopathy [n=2]) and in three (1%) patients in the lenvatinib plus placebo group (due to gastrointestinal haemorrhage, hepatorenal syndrome, and cerebrovascular accident [n=1 each]). Interpretation In earlier studies, the addition of pembrolizumab to lenvatinib as first-line therapy for advanced hepatocellular carcinoma has shown promising clinical activity; however, lenvatinib plus pembrolizumab did not meet prespecified significance for improved overall survival and progression-free survival versus lenvatinib plus placebo. Our findings do not support a change in clinical practice. Funding Eisai US, and Merck Sharp & Dohme, a subsidiary of Merck
Lenvatinib plus pembrolizumab versus lenvatinib plus placebo for advanced hepatocellular carcinoma (LEAP-002): a randomised, double-blind, phase 3 trial
Background Systemic therapies have improved the management of hepatocellular carcinoma, but there is still a need to further enhance overall survival in first-line advanced stages. This study aimed to evaluate the addition of pembrolizumab to lenvatinib versus lenvatinib plus placebo in the first-line setting for unresectable hepatocellular carcinoma.Methods In this global, randomised, double-blind, phase 3 study (LEAP-002), patients aged 18 years or older with unresectable hepatocellular carcinoma, Child Pugh class A liver disease, an Eastern Cooperative Oncology Group performance status of 0 or 1, and no previous systemic treatment were enrolled at 172 global sites. Patients were randomly assigned (1:1) with a central interactive voice-response system (block size of 4) to receive lenvatinib (bodyweight <60 kg, 8 mg/day; bodyweight >= 60 kg, 12 mg/day) plus pembrolizumab (200 mg every 3 weeks) or lenvatinib plus placebo. Randomisation was stratified by geographical region, macrovascular portal vein invasion or extrahepatic spread or both, alpha-fetoprotein concentration, and Eastern Cooperative Oncology Group performance status. Dual primary endpoints were overall survival (superiority threshold at final overall survival analysis, one-sided p=0019; final analysis to occur after 532 events) and progression-free survival (superiority threshold one-sided p=0002; final analysis to occur after 571 events) in the intention-to-treat population. Results from the final analysis are reported. This study is registered with ClinicalTrials.gov, NCT03713593, and is active but not recruiting.Findings Between Jan 17, 2019, and April 28, 2020, of 1309 patients assessed, 794 were randomly assigned to lenvatinib plus pembrolizumab (n=395) or lenvatinib plus placebo (n=399). Median age was 660 years (IQR 570-720), 644 (81%) of 794 were male, 150 (19%) were female, 345 (43%) were Asian, 345 (43%) were White, 22 (3%) were multiple races, 21 (3%) were American Indian or Alaska Native, 21 (3%) were Native Hawaiian or other Pacific Islander, 13 (2%) were Black or African American, and 46 (6%) did not have available race data. Median follow up as of data cutoff for the final analysis (June 21, 2022) was 321 months (IQR 294-353). Median overall survival was 212 months (95% CI 190-236; 252 [64%] of 395 died) with lenvatinib plus pembrolizumab versus 190 months (172-217; 282 [71%] of 399 died) with lenvatinib plus placebo (hazard ratio [HR] 084; 95% CI 071-100; stratified log-rank p=0023). As of data cutoff for the progression-free survival final analysis (April 5, 2021), median progression-free survival was 82 months (95% CI 64-84; 270 events occurred [42 deaths; 228 progressions]) with lenvatinib plus pembrolizumab versus 80 months (63-82; 301 events occurred [36 deaths; 265 progressions]) with lenvatinib plus placebo (HR 087; 95% CI 073-102; stratified log-rank p=0047). The most common treatment-related grade 3-4 adverse events were hypertension (69 [17%] of 395 patients in the lenvatinib plus pembrolizumab group vs 68 [17%] of 395 patients) in the lenvatinib plus placebo group), increased aspartate aminotransferase (27 [7%] vs 17 [4%]), and diarrhoea (25 [6%] vs 15 [4%]).Treatment-related deaths occurred in four (1%) patients in the lenvatinib plus pembrolizumab group (due to gastrointestinal haemorrhage and hepatorenal syndrome [n=1 each] and hepatic encephalopathy [n=2]) and in three (1%) patients in the lenvatinib plus placebo group (due to gastrointestinal haemorrhage, hepatorenal syndrome, and cerebrovascular accident [n=1 each]).Interpretation In earlier studies, the addition of pembrolizumab to lenvatinib as first-line therapy for advanced hepatocellular carcinoma has shown promising clinical activity; however, lenvatinib plus pembrolizumab did not meet prespecified significance for improved overall survival and progression-free survival versus lenvatinib plus placebo. Our findings do not support a change in clinical practice