[Levels of human milk oligosaccharides in breast milk of mothers delivering preterm infants of different gestational ages and their effects on early growth and development]

Objective: To investigate the human milk oligosaccharides (HMOs) levels in breast milk of mothers delivering preterm infants and their effects on the early growth and development of infants. Methods: In this prospective cohort study, full-term and preterm newborns whose parents decided to breastfeed were recruited from Peking University Third Hospital between December 1, 2017 and November 30, 2018. The preterm infants were divided based on their gestational ages into extremely preterm (<28 weeks), very preterm (28-31⁺⁶ weeks) and moderate to late preterm (32-36⁺⁶ weeks) groups. Breast milk was collected from mothers at 7, 14, 28 and 120d postpartum. 368 breast milk samples were collected from 125 mothers in this study, including 54 mothers of full-term infants, 23 mothers of moderate to late preterm infants, 39 mothers of very preterm infants, and 9 mothers of extremely preterm infants. Ultra-performance liquid chromatography-mass spectrometer (UPLC-MS/MS) was used to determine the concentration of 2'-fucosyllactose (2'FL), 3-fucosyllactose (3FL), 3'-sialyllactose (3'SL), A-tetrasaccharide (P1), lacto-N-tetraose (LNT), lacto-N-neotetraose (LNnT), lacto-N-fucopentaose Ⅱ (LNFP-Ⅱ) and lacto-N-fucopentaose Ⅴ (LNFP-Ⅴ). Secretor status of mothers was defined as 2'-fucosyllactose (2'FL) concentration in colostrum and transitional milk greater than 200 μg/mL. Weight gain and the occurrence of allergic diseases of infants were collected at 120 d(4 months) postpartum. The chi-square test or the Fisher's exact test was used for the comparison of categorical data between groups; Kruskal-Wallis test and Wilcoxon rank sum test were used for comparison of continuous data between groups. Nemenyi test was used for multiple comparison. Results: 79.2% (99/125) of the mothers were secretor. There were no statistical differences between groups in the secretor status of mothers (χ²=1.31,P>0.05). The total concentration of HMOs peaked at 1-2 weeks postpartum. Compared to the preterm milk, the HMOs from the term milk was trending downwards at an earlier time. In the breast milk of secretor mothers on 28 d, total concentration of HMOs significant differed among the three groups of preterm milk and the term milk, with the median value of 4 587.09,4 615.25,5 277.44,5 476.03 μg/mL, respectively (Kruskal-Wallis χ²=8.1234,P=0.044). When analyzed by the median weight gain of the infants (low vs high weight gain) at 4 months postpartum, 2'FL was significantly lower in the high weight gain group at 7 d (1 818.04 μg/mL vs 2 181.67 μg/mL, W=1 386,P=0.018), while LNT & LNnT were significantly higher (1 182.36 μg/mL vs 1 053.62 μg/mL, W=816,P=0.044). The level of 3FL at 120 d was significantly affected by presence of allergic disease in infants, breast milk from mothers of infants with allergic disease had lower 3FL than those from mothers of infants without allergic disease (256.17 μg/mL vs 286.18 μg/mL, W=564,P=0.026). Conclusions: The overall profiles of HMOs in breast milk of mothers delivering preterm infants was basically the same as that of mothers delivering term infants; individual HMOs play a role in weight gain and the development of allergic diseases in preterm infants, but the mechanism is unclear and needs further study.

Diets varying in ratio of sweet sorghum silage to corn silage for lactating dairy cows: Feed intake, milk production, blood biochemistry, ruminal fermentation, and ruminal microbial community

The objective of this study was to investigate the effects of partial substitution of corn silage (CS) with sweet sorghum silage (SS) in the diets of lactating dairy cows on dry matter (DM) intake, milk yield and composition, blood biochemistry, and ruminal fermentation and microbial community. Thirty mid-lactation Holstein dairy cows [mean ± standard deviation; 639 ± 42.0 kg of body weight; 112 ± 24.0 d in milk (DIM)] were assigned to 3 groups (n = 10/treatment) by considering parity, milk yield, and DIM. The cows were fed ad libitum total mixed rations containing 55% forage and 45% concentrate, with only the proportion of CS and SS varying in 3 treatments (DM basis): SS0 (0% substitution of CS), 40% CS and 0% SS; SS25 (25% substitution of CS)_, 30% CS and 10% SS; and SS50 (50% substitution of CS)_, 20% CS and 20% SS. Dry matter intake and milk protein concentration tended to linearly decrease with increasing proportion of SS in the diet. Yields of milk (mean ± standard deviation, 30.9 ± 1.12 kg/d), 4% fat-corrected milk (30.0 ± 0.81 kg/d), energy-corrected milk, milk protein, lactose, and total solids, concentrations of milk fat, lactose, somatic cell counts, and milk efficiency did not differ among diets. The concentrations in blood of urea nitrogen, phosphorus, aspartate aminotransferase, and malondialdehyde linearly increased with increasing SS proportion. Blood IgA decreased with increasing SS substitution rate, but blood IgG and IgM were not different among diets. Ruminal pH did not differ among diets, whereas ruminal NH₃-N concentration quadratically changed such that it was greater for SS50 than for SS0 and SS25. Molar proportions of propionate and acetate to propionate ratio were less for SS25 than for SS0. Although the diversity and general ruminal microbial community structure were not altered by partially replacing CS with SS, the relative abundances of predominant bacteria were affected by diets at the phylum and genus levels. Firmicutes and Bacteroidetes were dominant phyla in the ruminal bacterial community for all diets, and their relative abundance linearly decreased and increased, respectively, with increasing SS substitution rate. Prevotella_1 and Ruminococcaceae_NK4A214_group were detected as the most and the second most abundant genera, with their relative abundance linearly increased and decreased, respectively, with increasing SS substitution rate. The relative abundance of Fibrobacter linearly increased with increasing dietary SS proportion, with greater abundance observed for SS25 and SS50 than for SS0. These results suggest that substitution of CS with SS altered the relative abundances of some predominant bacteria; however, these changes had little effect on ruminal fermentation and milk yield. Under the current experimental conditions, substituting up to 50% of CS with SS had no negative effects on milk yield, indicating that SS can partially replace CS in the diets of high-producing lactating dairy cows without adding extra grain, when diets are fed for a short time. As the effects of substituting CS with SS depend upon the chemical composition and digestibility of these silages and the nutrient requirements of the cows, additional grain may be required in some cases to compensate for the lower starch content of SS.

Development of solid state terahertz interferometer for the first plasma on HL-2M tokamak

A solid state terahertz interferometer has been developed on the recent commissioned HL-2M tokamak. It can work in a wide frequency region of 220-325 GHz, and the terahertz wave is generated from a low frequency phase locked voltage controlled oscillator with the frequency multiplying technique. A phase processor based on field programmable gate array (FPGA) technology is designed for the heterodyne interferometer, and it contributes to real-time display of electron density. To extract phase information, a novel numerical algorithm related to fast Fourier transform is written on the FPGA chip and enables one to obtain phase shift without being affected by amplitude variation induced by plasma absorption or frequency modulation from the outer electromagnetic environment. The interferometer achieves minimum measurable electron density in the order of 10¹⁶ m^-3. With the plasma diagnosis, electron density and low frequency tearing mode have been measured during the first experimental campaign.

[Plasm trimethylamine-N-oxide level and association with lesion severity in coronary heart disease patients with type 2 diabetes mellitus]

Objective: To investigate the association between trimethylamine-N-oxide (TMAO) and the degree of coronary atherosclerosis in coronary heart diseases (CHD) patients with type 2 diabetes mellitus. Methods: Consecutive patients, who underwent coronary angiography due to suspected CHD in Beijing Hospital from November 2016 to January 2018, were screened in this cross-sectional study. According to blood glucose level, previous medical history and coronary angiography results, they were divided into CHD without type2 diabetes mellitus(CHD-nDM) group and CHD with type2 diabetes mellitus(CHD-DM) group. Plasma TMAO levels in each group were measured by LC-MS/MS. Spearman correlation analysis was used to evaluate the correlation between TMAO and the number of diseased vessels and Gensini scores. Multivariate logistic regression was used to analyze the correlation between TMAO and high Gensini scores. Results: A total of 590 patients were enrolled in the study, including 238 patients in CHD-DM group and 352 patients in CHD-nDM group. Patients were older, body mass index, blood pressure level, prevalence of history of hypertension and statins use were higher in CHD-DM group than in CHD-nDM group (all P<0.05). The proportion of patients with multivessel disease (2 or more vessels) was also higher in CHD-DM group than in CHD-nDM group (P<0.001). Gensini score was higher in CHD-DM group than in CHD-nDM group (P<0.05). Fasting blood glucose, glycosylated hemoglobin and urea were significantly higher, while low-density lipoprotein cholesterol and hemoglobin were significantly lower in CHD-DM group than in CHD-nDM group (all P<0.05). The levels of TMAO was significantly higher in CHD-DM group than in CHD-nDM group (P<0.001). Spearman correlation analysis showed that TMAO was positively correlated with the number of diseased vessels, Gensini score, age and blood glucose level (r=0.178, 0.189, 0.260, 0.111, respectively, all P<0.01). Multivariate logistic regression analysis showed that, TMAO level was still positively correlated with high Gensini score in CHD-DM group (OR=2.25, 95%CI 1.16-4.38, P=0.017), but not in CHD-nDM group (OR=1.29, 95%CI 0.72-2.31, P=0.386) after adjusting for age, sex, body mass index, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, total cholesterol, triglyceride, history of hypertension, hyperlipidemia, smoking and statin use. Conclusions: In CHD patients with tupe 2 diabetes mellitus, the plasma TMAO level is significantly increased and is independent and positively correlated with the degree of coronary artery disease.

Abstract CT039: Results from RATIONALE 303: A global phase 3 study of tislelizumab (TIS) vs docetaxel (TAX) as second- or third-line therapy for patients with locally advanced or metastatic NSCLC

Results From RATIONALE 303: A Global Phase 3 Study of Tislelizumab (TIS) vs Docetaxel (TAX) as Second- or Third-Line Therapy for Patients With Locally Advanced or Metastatic NSCLC

Background: Anti-PD-1/L1 therapies have improved OS by 2-4 mo vs TAX in patients (pts) with advanced NSCLC who progressed after platinum regimens. TIS is an anti-PD-1 antibody engineered to minimize FcγR binding on macrophages, a mechanism of T-cell clearance and potential anti-PD-1 resistance.

Methods: RATIONALE 303 (BGB-A317-303; NCT03358875) compared efficacy and safety of TIS vs TAX as 2 or 3L therapy for pts with advanced NSCLC. Patients without oncogenic driver mutation who failed at least 1 prior systemic therapy including a platinum regimen were randomized 2:1 to receive TIS 200 mg IV Q3W (Arm A) or TAX 75 mg/m2 IV Q3W (Arm B). Dual primary endpoints were OS in the ITT analysis set and OS in the PD-L1 high (≥25% TC) analysis set. A prespecified interim analysis (IA) was conducted after ≈426 deaths (76% of planned events); in the IA, formal OS superiority testing was conducted only in the ITT. The IA results are presented.

Results: Overall, 805 pts were randomized (n=535, TIS; n=270, TAX); demographics were generally balanced between arms. With a 19-mo median follow-up (441 OS events), median OSITT was significantly longer in Arm A vs B (17.2 vs 11.9 mo; HR=0.64 [95% CI: 0.53, 0.78]; P&lt;.0001). OS benefit was also observed in the PD-L1 high analysis set (19.1 vs 11.9 mo; HR=0.52 [95% CI: 0.38, 0.71]) and across most subgroups including histology. In the ITT analysis set, PFS, ORR, and DoR were also improved in Arm A vs B (Table). Anemia (TIS) and alopecia (TAX) were the most commonly reported AEs (Table); pneumonia (TIS) and neutropenia (TAX) were the most common grade ≥3 AEs. AEs leading to death were 6.0% (TIS) and 4.3% (TAX); treatment-related AEs leading to death were 1.5% (TIS) and 1.6% (TAX).

Conclusions: RATIONALE 303 demonstrated that, as 2 or 3L therapy in pts with advanced NSCLC, TIS was tolerable and prolonged OS by 5-7 mo with improved PFS and ORR vs TAX regardless of histology or PD-L1 expression.

ITT Analysis Set (N=805)Arm A Tislelizumab (n=535)Arm B Docetaxel (n=270)EfficacyMedian OS, mo17.211.9OS difference, mo5.3HR (95% CI)a0.64 (0.53, 0.78)P-valuea,b&lt;0.0001Median PFS, mo4.12.6PFS difference, mo1.5HR (95% CI)a0.64 (0.53, 0.76)P-valuea,b&lt;0.0001cORR, n (%)117 (21.9)19 (7.0)ORR difference, %14.9OR (95% CI)3.71 (2.24, 6.14)P-valued&lt;0.0001cMedian DoR, mo (95% CI)13.5 (8.5, 21.8)6.2 (2.1, 7.2)Adverse event profileAEs occurring in ≥15% of patients in either arm, n (%)All gradeGrade ≥3All gradeGrade ≥3Anemia152 (28.5)18 (3.4)112 (43.4)16 (6.2)Alanine aminotransferase increased106 (19.9)4 (0.7)38 (14.7)0Cough104 (19.5)5 (0.9)40 (15.5)1 (0.4)Aspartate aminotransferase increased101 (18.9)5 (0.9)31 (12.0)1 (0.4)Appetite decreased82 (15.4)5 (0.9)59 (22.9)3 (1.2)Weight decreased81 (15.2)4 (0.7)26 (10.1)0Alopecia5 (0.9)0122 (47.3)2 (0.8)Neutrophil count decreased15 (2.8)3 (0.6)95 (36.8)71 (27.5)Neutropenia9 (1.7)3 (0.6)81 (31.4)72 (27.9)White blood cell count decreased20 (3.7)1 (0.2)74 (28.7)47 (18.2)Leukopenia15 (2.8)1 (0.2)69 (26.7)41 (15.9)Asthenia67 (12.5)6 (1.1)56 (21.7)14 (5.4)Constipation65 (12.2)042 (16.3)0Hypoalbuminemia70 (13.1)041 (15.9)1 (0.4)Nausea59 (11.0)041 (15.9)1 (0.4)Abbreviations: AE, adverse event; DoR, duration of response; HR, hazard ratio; ITT, intent-to-treat; mo, months; NA, not available; OR, odds ratio; ORR, objective response rate; PFS, progression-free survival.aStratified.bOne-sided log-rank test.cDescriptive P-value.dCochran-Mantel-Haenszel.

Citation Format: Caicun Zhou, Dingzhi Huang, Xinmin Yu, Yunpeng Liu, Yun Fan, Yongqian Shu, Zhiyong Ma, Ziping Wang, Ying Cheng, Jie Wang, Sheng Hu, Zhihua Liu, Mikhail Dvorkin, Elena Poddubskaya, Umut Disel, Andrey Akopov, Yiyuan Ma, Yan Wang, Zhenyu Pan, Cunjing Yu, Gareth Rivalland. Results from RATIONALE 303: A global phase 3 study of tislelizumab (TIS) vs docetaxel (TAX) as second- or third-line therapy for patients with locally advanced or metastatic NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT039.

Assessing alfalfa (Medicago sativa L.) tolerance to salinity at seedling stage and screening of the salinity tolerance traits

Salt is among the most harmful agents that negatively influences crop yield. Alfalfa is an important perennial forage crop that exhibits wide cultivar variations in salt tolerance. Developing salt-tolerant alfalfa plants is a promising way to utilize salinized land. A comprehensive method was developed to achieve reliable and effective evaluation of alfalfa salt resistance. This included principal components, membership functions and cluster and stepwise regression analyses. These were used to analyse the salt tolerance coefficients of 14 traits and to evaluate 20 diverse alfalfa cultivars at the seedling stage. The various morphological root parameters of six alfalfa cultivars with contrasting salt tolerance were also tested by a scanning apparatus. According to the comprehensive evaluation value (D value), one highly salt-tolerant, two salt-tolerant, four moderately salt-tolerant and 13 salt-sensitive alfalfa cultivars were screened. A mathematical equation for the evaluation of alfalfa salt tolerance was established: D' = -0.126 + 0.667SFW + 0.377SDW + 1.089K⁺ /Na⁺  + 0.172SFW/RFW (R²  = 0.988; average forecast accuracy of 96.95%), where four indices were closely related to the salt tolerance: shoot fresh weight, ratio of shoot fresh weight to root fresh weight, shoot dry weight and ratio of K⁺ to Na⁺ in the shoot. We also found that SSA correlated strongly with SFW, SDW, K⁺ /Na⁺ , D values, while SRV correlated obviously with SFW, SFW/RFW and D values after 150 mm NaCl treatment. In conclusion, the SFW, K⁺ /Na⁺ , SDW, SFW/RFW, SSA and SRV could be used as indicators of salt tolerance in alfalfa seedlings grown under 150 mm NaCl treatment.

Abstract CT041: ORIENT-3: A randomized, open-label, phase 3 study of sintilimab versus docetaxel in previously treated advanced/metastatic squamous non-small-cell lung cancer (sqNSCLC)

Background: Patients (pts) with advanced squamous NSCLC (sqNSCLC) have very limited second-line treatment options after failure of the platinum-based doublet chemotherapy. ORIENT-3 was conducted to compare the efficacy and safety of sintilimab, an anti-PD-1 antibody, with docetaxel in second-line treatment in sqNSCLC. (NCT03150875) Method: Pts with stage IIIB/IIIC or IV (ineligible for radical chemo-radiotherapy) sqNSCLC who have disease progression during or after first-line platimum-based chemotherapy were enrolled and randomized 1:1 to receive sintilimab 200mg (Sin arm) or docetaxel 75mg/m2 (Doc arm) intravenously, Q3W until disease progression or intolerable toxicity. Stratification factor was ECOG score (0 vs. 1). The primary endpoint was overall survival (OS). Results: As of July 31, 2020, 290 pts were enrolled with 145 in each treatment group. Efficacy analysis was based on FAS (n=280), and safety analysis was based on safety set (n=274). Baseline characteristics were well balanced between treatment groups, and most pts in efficacy analysis (75.9% in Sin arm, 77.0% in Doc arm) had ECOG PS score of 1. Pts received a median of 8.0 cycles (range: 1-45) of sintilimab, and 2.0 cycles of docetaxel (range: 1-15). With a median follow-up of 23.56 months, sintilimab had a significant improvement in OS versus docetaxel (median: 11.79 m [95% CI 10.28-15.57] vs. 8.25 m [95% CI 6.47-9.82]; HR 0.74, [95%CI 0.56-0.96], P = 0.02489). The median PFS was also significantly superior in Sin arm (4.30 m, 95% CI 4.04-5.78) to that in Doc arm (2.79 m, 95% CI 1.91-3.19) (HR 0.52, 95% CI 0.39-0.68, P&lt;0.00001). The confirmed ORR was 25.5% (95% CI, 18.6%-33.4%) in Sin arm and 2.2% (95% CI 0.5%-6.4%) in Doc arm. 84.7% of pts in Sin arm and 83.1% in Doc arm reported treatment-related adverse events (TRAEs), most commonly with hypothyroidism (18.1%) and alopecia (34.6%), respectively. TRAEs ≥ grade 3 were less frequent in Sin arm (18.1%) than in Doc arm (36.2%). Five pts occurred sintilimab-related death, and one death reported relating with docetaxel. Conclusion: Sintilimab as second-line treatment for advanced and metastatic sqNSCLC showed a superior OS and PFS benefit, compared with docetaxel.

Citation Format: Yuankai Shi, Lin Wu, Xinmin Yu, Yan Wang, Puyuan Xing, Jianying Zhou, Airong Wang, Jianhua Shi, Yi Hu, Ziping Wang, Guangyu An, Yong Fang, Sanyuan Sun, Caicun Zhou, Changli Wang, Feng Ye, Xingya Li, Junye Wang, Mengzhao Wang, Yunpeng Liu, Yanqiu Zhao, Jifeng Feng. ORIENT-3: A randomized, open-label, phase 3 study of sintilimab versus docetaxel in previously treated advanced/metastatic squamous non-small-cell lung cancer (sqNSCLC) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr CT041.

[Four cases of acute diquat poisoning with prominent epileptoid seizure and literature review]

Objective: To further improve the awareness of the clinical feature of acute diquat poisoning. Methods: A retrospective analysis was performed on 4 cases of acute diquat poisoning with epileptoid seizure as the main clinical manifestation, which were admitted and diagnosed by the Characteristic Medical Center of Chinese People's Armed Police Force from January 1, 2017 to December 31, 2019. Take "Diquat" or "Deiquat" or "Reward" as keyword search for CNKI, Pubmed, and EMbase in both Chinese and English. The date of literature retrieval was from the database founding to December 31, 2019. Results: Of the 4 patients, 3 were male and 1 female, with an average age of 28 years (22-33 years) . The estimated dose was 8-20 g. All patients were treated with gastric lavage, catharsis, fluid replacement, blood perfusion, and in the early stage of treatment of epileptic seizures, the initial routine antiepileptic drugs had poor effect. Then propofol and midazolam were injected into the treatment. The epilepsy was relieved, but the condition deteriorated rapidly, and the patients died eventually. The literature search retrieved 3 patients in the 3 literatures included in the study were analyzed, and their clinical course was similar to that of 4 cases in the center. Necropsy was performedon all 3 patients, and the results were cerebral edema, diffuse cerebral edema, and hemorrhage around the basal ganglia. Conclusion: Acute diquat poisoning can cause epileptic seizures. Once it occurs, the disease progresses rapidly and the prognosis is poor. The combination of large dose of sedative drugs can be used to treat epilepsy in order to improve the prognosis.

Outcomes of switching from crizotinib to alectinib in patients with advanced non-small cell lung cancer with anaplastic lymphoma kinase fusion

Background

Alectinib and crizotinib have been approved as first-line therapies for advanced non-small cell lung cancer (NSCLC) with anaplastic lymphoma kinase (ALK) gene fusion. However, the therapeutic efficacy and side effects are still largely unknown of patients who switched to next-generation ALK tyrosine kinase inhibitors (ALK-TKIs), such as alectinib, after experiencing no disease progression with initial crizotinib treatment.

Methods

This prospective real-world study enrolled patients who were treated with alectinib after experiencing no disease progression with initial crizotinib treatment. The patients’ baseline characteristics, objective response rate (ORR) of crizotinib and alectinib, size change of target tumor lesions, treatment regimen and adverse events (AEs) were collected and analyzed.

Results

The study included 53 patients, the majority of whom (96.2%) had non-squamous NSCLC. The median age was 51 (range, 31–80) years old. The ORR of first-line crizotinib was 54.7%. The ORR of sequential alectinib was 73.6%, and 90.5% of patients showed further tumor shrinkage after the alectinib treatment. The median progression-free survival was not reached, and 90.5% of patients were still enrolled in the study at the last follow-up. Among them, 34.0% of patients switched to alectinib treatment due to the toxicity. Crizotinib was associated with a higher frequency of AEs of grades 3 and 4 than alectinib (15.1% vs. 0%). Neither group had any AEs resulting in death.

Conclusions

Switching to alectinib might be an option for patients who do not experience disease progression with initial crizotinib therapy, and may promote better treatment compliance.

AB0197 EFFICACY AND SAFETY OF HLX01 COMBINED WITH METHOTREXATE IN CHINESE PATIENTS WITH MODERATELY TO SEVERELY ACTIVE RHEUMATOID ARTHRITIS WHO HAD INADEQUATE RESPONSES TO METHOTREXATE: RESULTS OF A RANDOMISED, DOUBLE-BLIND, PLACEBO-CONTROLLED PHASE 3 STUDY

Background:

Rituximab is an effective therapy for rheumatoid arthritis (RA) patients with inadequate responses to methotrexate (MTX)1, 2. However, it has not been registered or approved in China for the treatment of RA by far. HLX01, an approved rituximab biosimilar (demonstrated in Chinese patients with diffuse large B-cell lymphoma)3, is thus evaluated in this study for the benefits of Chinese RA patients.

Objectives:

This study aimed to evaluate the efficacy and safety of HLX01 plus MTX versus placebo plus MTX in Chinese patients with active RA who had inadequate responses to MTX.

Methods:

This was a randomised, double-blind, placebo-controlled phase 3 study conducted in China (NCT03522415). Eligible patients were randomised 2:1 to receive intravenous infusion of 2×1000 mg HLX01 or placebo on day 1 and day 15. Patients with inadequate responses at week 16 and 20 were allowed to receive rescue treatments. Patients were retreated with or switched to receive (if initially assigned to placebo) 2×1000 mg rituximab at the first day of week 24 and 26. The primary endpoint of this study was the American College of Rheumatology criteria (ACR) 20 response at week 24. Secondary efficacy endpoints were evaluated at week 12, 24, 36 and 48. The safety, pharmacokinetics, pharmacodynamics and immunogenicity of HLX01 were observed and analyzed throughout the study.

Results:

Between May 28, 2018 and Sep 11, 2020, a total of 275 patients (ITT set) were randomised and 263 patients without major protocol deviations were included in per-protocol set (PPS). At week 24, HLX01 showed statistically superior efficacy (p <0.001) to placebo (ACR20: 60.7% vs 35.9% in ITT set, 60.3% vs 37.1% in PPS). Secondary efficacy endpoints were also significantly improved in HLX01 group compared with placebo (Table 1). The overall incidence of serious treatment emergent adverse events (TEAEs), adverse drug reactions (ADRs), and TEAEs leading to drug discontinuation were similar among treatment groups, with the most common TEAE been upper respiratory tract infection before (18.1% vs 18.5%) or after (13.0% vs 12.3%) week 24. Serum concentrations, immunogenicity and pharmacodynamics were similar between HLX01 and placebo groups.

Table 1.

Results of secondary efficacy endpoints at week 12, 24, 36 and 48 in ITT set.

DurationSecondary efficacy endpointsACR20 (%)ACR50 (%)ACR70 (%)DAS28-CRP(mean)HAQ-DI(mean)HLX01PlaceboHLX01PlaceboHLX01PlaceboHLX01PlaceboHLX01PlaceboBaseline5.495.431.401.45Week 1248.132.621.910.94.45.43.894.471.021.22Week 2460.735.936.618.515.312.03.394.370.871.22Week 3660.148.946.431.532.217.42.883.510.710.97Week 4873.862.055.240.239.927.22.823.510.721.03

Conclusion:

Comparing with placebo plus MTX, HLX01 plus MTX showed significantly improved clinical outcomes and comparable safety profiles in Chinese patients with moderately to severely active RA who had inadequate responses to MTX, demonstrating HLX01 in combination with MTX as a well-tolerated, safe and efficient treatment option.

References:

[1]Emery P, Deodhar A, Rigby WF, et al. Efficacy and safety of different doses and retreatment of rituximab: a randomised, placebo-controlled trial in patients who are biological naive with active rheumatoid arthritis and an inadequate response to methotrexate (Study Evaluating Rituximab’s Efficacy in MTX iNadequate rEsponders (SERENE)). Ann Rheum Dis. Sep 2010;69(9):1629-35. doi:10.1136/ard.2009.119933.

[2]Rubbert-Roth A, Tak PP, Zerbini C, et al. Efficacy and safety of various repeat treatment dosing regimens of rituximab in patients with active rheumatoid arthritis: results of a Phase III randomized study (MIRROR). Rheumatology (Oxford). Sep 2010;49(9):1683-93. doi:10.1093/rheumatology/keq116.

[3]Shi Y, Song Y, Qin Y, et al. A phase 3 study of rituximab biosimilar HLX01 in patients with diffuse large B-cell lymphoma. J Hematol Oncol. Apr 16 2020;13(1):38. doi:10.1186/s13045-020-00871-9.

Acknowledgements:

The authors would like to thank participants in this study and their families. They would also like to acknowledge other investigators and staff at all clinical sites and the members of the Independent Data Monitoring Committee.

Disclosure of Interests:

None declared

AB0762 THE CHARACTERISTICS OF PERIPHERAL LYMPHOCYTE SUBSETS IN PATIENTS WITH IGG4-RELATED DISEASE

Background:

Immunoglobulin G4-related disease (IgG4-RD) is an autoimmune disease with chronic systemic inflammation and fibrosis. The main feature of the disease was diffuse swell of the affected organs, and the serum IgG4 level was increased. Histopathology of the lesions showed infiltration of IgG4+ plasma cells. However, the pathogenesis of IgG4-RD is still unclear[1].

Objectives:

To explore the clinical characteristic of lymphocyte subsets of IgG4-related disease patients, and make comparisons with healthy controls.

Methods:

A total of 31 patients with IgG4-RD who were admitted to the Rheumatic Immunology Department of the Second Hospital of Shanxi Medical University from January 2016 to June 2020 were included. We collected their Clinical and laboratory data, and selected 30 age and sex matched healthy people as the control group. Flow cytometry was used to detect the percentage and absolute number of lymphocyte subsets (T, B, NK, CD4+T, CD8+T) and CD4+T subsets (Th1, Th2, Th17, CD4+CD25+Foxp3+Treg) in peripheral blood of IgG4-RD patients and healthy controls.

Results:

(1)The percentage of CD4+T cells in peripheral blood of IgG4-RD patients was higher than that of healthy controls [45.00(33.97-51.48) vs. 39.36(33.78-43.30), P<0.05]. (2)The percentage and absolute number of Th17 cells was increased in IgG4-RD patients [1.13(0.70-1.55) vs. 0.77(0.43-1.07), P<0.05; 7.90(5.20-12.23) vs. 5.60(3.12-8.47), P<0.05], while the percentage of Treg cells was decreased [3.37(2.82-5.65) vs. 4.96(4.18-6.34), P<0.01]. But Treg cells number showed no difference between the two groups. (3) Th17/Treg ratio was significantly increased in IgG4-RD patients [0.29(0.16-0.46) vs. 0.15(0.08-0.23), P<0.01], and it was positively correlated with IgG4-RD response index score(r=0.491, P<0.01). (Table 1).

Table 1.

Comparation of absolute number and percentage of peripheral blood lymphocyte subsets between IgG4-RD patients(n=31) and healthy controls (n=30).

cell subsetsIgG4-RD (n=31)HC(n=30)P valueB150.59(120.14-212.38)203.27(152.90-244.27)0.089B%8.74(6.46-11.45)10.03(8.26-13.21)0.059NK261.98(178.82-303.08)290.83(179.93-451.45)0.175NK%13.14(9.92-18.10)16.50(11.24-21.75)0.105CD3+T1357.44(992.00-1844.82)1305.81(978.24-1597.94)0.708 CD3+T%72.62(69.32-76.96)71.62(64.97-75.25)0.135CD8+T436.40(342.71-596.86)513.50(359.73-620.53)0.665CD8+T%24.26(19.48-31.27)26.50(20.67-32.90)0.535CD4+T741.00(562.78-1095.52)664.50(585.52-789.97)0.428CD4+T%45.00(33.97-51.48)39.36(33.78-43.30)0.032Th1162.32(108.11-216.61)144.27(81.52-161.66)0.094Th1%19.00(15.24-25.54)18.46(14.86-24.27)0.644Th27.82(5.35-11.78)8.25(5.32-10.87)0.817Th2%1.00(0.76-1.27)1.24(0.89-1.64)0.399Th177.90(5.20-12.23)5.60(3.12-8.47)0.010Th17%1.13(0.70-1.55)0.77(0.43-1.07)0.026Treg24.45(19.76-44.79)34.55(27.29-46.57)0.076Treg%3.37(2.82-5.65)4.96(4.18-6.34)0.003Th1/Th220.00(13.78-36.36)14.97(10.31-21.58)0.135Th1/Treg5.72(2.92-8.86)3.68(2.53-4.77)0.021Th2/Treg0.27(0.16-0.52)0.22(0.15-0.32)0.199Th17/Treg0.29(0.16-0.46)0.15(0.08-0.23)0.002

Conclusion:

Th17/Treg immune disorder exists in IgG4-RD patients, and it is related to the disease activity, indicating that Th17/Treg imbalance may be an important pathogenesis of IgG4-RD.

References:

[1]Kamisawa T, Zen Y, Pillai S, et al. IgG4-related disease[J]. Lancet, 2015, 385(9976): 1460-1471.

Disclosure of Interests:

None declared

Impact of recurrent outbreaks of Ebola virus disease in Africa: a meta-analysis of case fatality rates

OBJECTIVES

Between 2010 and 2020, Africa witnessed several outbreaks of Ebola virus disease (EVD), each presenting with varying case fatality rate (CFR) and other socio-economic impacts. This study aims to summarize the CFR and identify potential factors that influenced the severity of EVD outbreaks in Africa.

STUDY DESIGN

This was a systematic review and meta-analysis of EVD outbreaks published between January 2010 and March 2020, using Web of Science, Scopus, and PubMed databases.

METHODS

Only English-language articles and reports, including the number of cases and deaths during the outbreak in Africa, were considered. The quality of the included articles was assessed using Murad's quality assessment tool. The analysis was conducted using Stata (version 12), pooled effect sizes were calculated using the random-effects model, and heterogeneity was tested for using the I² statistic.

RESULTS

Thirteen studies with 32,300 cases and 13,727 deaths were identified, whose pooled CFR was 60% (95% confidence interval [CI]: 47-73%). The most EVD-affected countries were the Democratic Republic of Congo with five outbreaks and a pooled CFR of 65% (95% CI: 59-71%), followed by Uganda with three outbreaks and CFR of 83% (95% CI: 60-99%). Zaire ebolavirus caused the most outbreaks (10), with a CFR of 58% (95% CI: 45-71%). Besides, outbreaks with fewer than 1000 cases reported a higher CFR rate (65%, 95% CI: 54-75%) compared with those with more cases (51%, 95% CI: 33-69%).

CONCLUSION

The study has revealed a considerably high CFR caused by the recurrent EVD outbreaks in Africa. It also notes an implementation gap in the prevention and control strategies and thus identifies a need to strengthen the surveillance systems and response mechanisms to enable early detection and prompt control of future outbreaks.

AdvanTIG-302: Anti-TIGIT monoclonal antibody (mAb) ociperlimab (OCI) plus tislelizumab (TIS) versus pembrolizumab (PEM) in programmed death ligand-1 (PD-L1) selected, previously untreated, locally advanced, unresectable or metastatic non-small cell lung cancer (NSCLC)

TPS9128

Background: Monotherapy with programmed death 1 (PD-1)/PD-L1 antibodies has improved clinical outcomes for patients (pts) with non-oncogenic driven NSCLC but clinical responses are limited by primary and secondary resistance, and improvements in durability of response are required. T-cell immunoreceptor with immunoglobulin and immunoreceptor tyrosine-based inhibition motif domain (TIGIT) is a co-inhibitory, immune checkpoint receptor upregulated on T-cells and natural killer cells in multiple solid tumors, which can inhibit anticancer immune responses. OCI (BGB-A1217) is a novel, humanized mAb that binds to TIGIT with high affinity and specificity, which has demonstrated competent binding with C1q and all Fcγ receptors while inducing antibody-dependent cellular cytotoxicity. Preclinical and clinical studies suggest that dual targeting with anti-TIGIT and anti-PD-1 antibodies produces synergistic immune cell activation and enhanced antitumor activity. Methods: AdvanTIG-302 is a Phase 3, multicenter, international, randomized, double-blind study (NCT04746924) investigating OCI in combination with TIS compared with PEM in adult pts (≥ 18 years of age) with PD-L1 selected, previously untreated, locally advanced, unresectable or metastatic NSCLC without oncogenic EGFR or ALK mutation. Approximately 605 pts will be randomized 5:5:1 to receive: OCI 900 mg intravenously (IV) plus TIS 200 mg IV every three weeks (Q3W; Arm A), PEM 200 mg IV plus placebo IV Q3W (Arm B) or TIS 200 mg IV plus placebo IV Q3W (Arm C). Pts will be treated until disease progression, loss of clinical benefit, intolerable toxicity or withdrawal of consent. Stratification factors include histology (squamous vs non-squamous) and region (Asian vs non-Asian). Cross-over is not permitted. Key eligibility criteria include histologically confirmed disease, PD-L1 expression ≥ 50%, no known EGFR or ALK mutations and no prior checkpoint inhibitor therapy. Dual primary endpoints are investigator-assessed progression-free survival (PFS; RECIST v1.1) and overall survival (Arms A and B) in the Intention-to-Treat population. Secondary endpoints include PFS (assessed by Blinded Independent Review Committee), investigator-assessed overall response rate and duration of response, safety and tolerability, and patient-reported health-related quality of life (EORTC-QLQ-C30, QLQ-LC13 and EQ-5D-5L; Arms A and B). Exploratory endpoints include disease control rate, clinical benefit rate and time to response. This study will also evaluate the association between biomarkers and response or resistance. Study enrollment has begun and recruitment is ongoing. Clinical trial information: NCT04746924.

RATIONALE 302: Randomized, phase 3 study of tislelizumab versus chemotherapy as second-line treatment for advanced unresectable/metastatic esophageal squamous cell carcinoma

4012

Background: Tislelizumab (tisle) monotherapy or plus chemotherapy demonstrated antitumor activity in patients (pts) with solid tumors, including esophageal squamous cell carcinoma (ESCC) (NCT03469557 and CTR20160872). Methods: In this global phase 3 study (NCT03430843), adults with histologically confirmed advanced/unresectable or metastatic ESCC whose disease progressed following prior systemic therapy with ≥1 evaluable lesion per RECIST v1.1 and an Eastern Cooperative Oncology Group performance score (ECOG PS) of ≤1 were included. Pts were randomized (1:1) to receive tisle 200 mg intravenously every 3 weeks or investigator-chosen standard chemotherapy ([ICC]; paclitaxel, docetaxel, or irinotecan) and treated until disease progression, unacceptable toxicity, or withdrawal. Stratification factors included ICC option, region, and ECOG PS. The primary endpoint was overall survival (OS) in the intent-to-treat (ITT) population. The key secondary endpoint was OS in the programmed death-ligand 1 (PD-L1)+ population (visually-estimated combined positive score [vCPS] ≥10%, by VENTANA PD-L1 SP263 assay). Other secondary endpoints included (by RECIST v1.1) progression-free survival, overall response rate (ORR), duration of response (DoR), and safety. Results: Overall, 512 pts (median age: 62 years; range 35-86 years) from 132 sites in 10 countries in Asia (404 pts [79%]), Europe, and North America (108 pts [21%]) were randomized to tisle (n=256) or ICC (n=256) (ITT population). Of these, 157 pts (tisle [n=89], ICC [n=68]) had vCPS ≥10% (PD-L1+ population). On 1 Dec 2020 (data cut-off), median follow-up was 8.5 months (m) with tisle and 5.8 m with ICC. The study met its primary endpoint: tisle clinically and significantly improved OS vs ICC in the ITT population (median OS: 8.6 vs 6.3 m; HR 0.70, 95% CI 0.57-0.85, p=0.0001). Tisle also demonstrated significant improvement in OS vs ICC in the PD-L1+ population (median OS: 10.3 vs 6.8 m; HR 0.54, 95% CI: 0.36-0.79, p=0.0006). Survival benefit was consistently observed across pre-defined subgroups, including baseline PD-L1 status and region. Treatment with tisle was also associated with a higher ORR (20.3% vs 9.8%) and more durable response (median DoR: 7.1 vs 4.0 m; HR 0.42, 95% CI 0.23-0.75) than ICC in the ITT population. Fewer pts had ≥Grade 3 (46% vs 68%) treatment-emergent adverse events with tisle vs ICC. Of these, fewer ≥Grade 3 AEs were treatment-related (TR) with tisle vs ICC (19% vs 56%). Fewer pts discontinued tisle vs ICC (7% vs 14%) due to a TRAE. Conclusion: Tisle demonstrated statistically significant and clinically meaningful improvement in OS vs ICC in pts with advanced or metastatic ESCC who had disease progression during or after first-line systemic therapy. Tisle showed a higher and longer response vs ICC. The safety profile of tisle was more favorable than ICC. Clinical trial information: NCT03430843.

RATIONALE-307: Tislelizumab plus chemotherapy versus chemotherapy alone as first-line treatment for advanced squamous NSCLC in patients aged ≥ 65

9102

Background: Tislelizumab is a humanized, monoclonal antibody with high affinity and specificity for the programmed cell death protein 1 (PD-1). It has demonstrated antitumor activity in advanced lung cancers. We conducted a Phase 3, multicenter, randomized open-label study (NCT03594747) to assess the safety and efficacy of tislelizumab plus chemotherapy in patients (pts) with advanced squamous NSCLC. As previously reported, tislelizumab (TIS) significantly improved progression free survival (PFS) and reduced the risk of progression. Here, we report results from a sub-group of pts aged ≥ 65 years. Methods: Eligible pts (aged 18-75 years) enrolled in China were treatment-naive for locally advanced or metastatic squamous NSCLC. Pts were stratified by disease stage (IIIB vs IV), and programmed death-ligand 1 (PD-L1) expression (<1% vs 1-49% vs 50% tumor cells), and randomized 1:1:1 to Arm A: TIS 200 mg + paclitaxel (P) 175 mg/m2 and carboplatin (C) area under the plasma concentration 5 (every 3 weeks [Q3W] on day 1); Arm B: TIS + nab-paclitaxel ( nab-P) 100 mg/m2 (Q3W on days 1, 8 and 15) + C (Q3W on Day 1); or Arm C: P + C (Q3W on day 1). P, nab-P and C were administered for 4 to 6 cycles. TIS was administered until loss of benefit, withdrawal of consent or start of a new anticancer therapy. In this sub-group analysis, pts aged ≥ 65 years were evaluated according to the primary endpoint (PFS) and key secondary endpoints (objective response rate and safety). Results: Overall, 127 pts aged ≥ 65 years were randomized to receive treatment. Median age of pts aged ≥ 65 was 68.0 years and 120 pts (94.5%) were male. In total, 18 (46.2%), 20 (38.5%), and 34 (94.4%) pts in Arms A, B and C, respectively, had discontinued treatment. In Arm C 22/34 pts had completed chemotherapy. The primary and secondary endpoints, PFS and ORR, were longer and higher, respectively, in Arms A and B, compared with Arm C (Table). Grade ≥ 3 treatment related adverse events (TRAEs) occurred in 33 (84.6%), 44 (84.6%) and 28 (82.4%) pts aged ≥ 65 years in Arms A, B and C, respectively, compared with 103 (85.8%), 99 (83.9%) and 94 (80.3%) pts aged ≥ 18 years enrolled in the study. The most commonly reported TRAEs in pts aged ≥ 65 years were anemia, decrease in neutrophil count, and alopecia. Conclusions: In this sub-group analysis, PFS and ORR were longer and higher, respectively, with TIS in pts aged ≥ 65 years with advanced squamous NSCLC. The safety profile of TIS in pts aged ≥ 65 years was similar to the safety profile for all aged pts aged ≥ 18 years. Clinical trial information: NCT03594747. [Table: see text]

Randomized phase III trial of aumolertinib (HS-10296, Au) versus gefitinib (G) as first-line treatment of patients with locally advanced or metastatic non-small cell lung cancer (NSCLC) and EGFR exon 19 del or L858R mutations (EGFRm)

9013

Background: Au is a novel, irreversible epidermal growth factor receptor tyrosine kinase inhibitor (EGFR TKI) with favorable pharmacologic properties that selectively inhibits both EGFR sensitizing and resistance mutations. Au has been approved in China for treatment of patients (pts) with EGFR mutant NSCLC with EGFR T790M upon progression of disease on previous EGFR TKIs (Proc. AACR 2020, Abstract CT190). This Phase III trial assessed the efficacy and safety of Au versus G as initial treatment of patients with advanced NSCLC with EGFRm. Methods: Pts with previously untreated metastatic or locally advanced NSCLC and EGFR exon 19 deletion or L858R were randomly assigned in a 1:1 ratio to receive either Au (110 mg once daily) or G (250 mg once daily). The primary endpoint was progression-free survival (PFS) by RECIST v1.1 per investigator assessment. At 262 PFS events, the study had 90% power to detect a PFS HR = 0.67. Secondary endpoints included overall survival (OS), objective response rate (ORR), duration of response (DoR) and safety. Results: Between Nov 30, 2018 and Sept 6, 2019, 429 patients across 53 sites in China were enrolled and randomized. Pt. characteristics were well-balanced. At the planned final event-driven PFS analysis, Au significantly prolonged PFS (median 19.3 vs 9.9 months, HR 0.46, p-value <0.0001). DoR was also significantly prolonged with Au. Median OS has not been reached. Efficacy and relevant safety results are summarized in Table. Despite a significantly longer duration of treatment (median 463 vs 254 days), Au was associated with a lower incidence of rash, diarrhea, AST/ALT increase, and treatment related serious adverse events (SAEs) (4.2% vs 11.2%). Au was associated with more frequent events of CPK increased, platelet count decreased, and neutrophil count decreased, which were predominantly low grade. Conclusions: Au significantly prolonged PFS and DoR compared to G as first-line therapy in pts with advanced NSCLC with EGFRm. Au demonstrated a favorable safety profile, especially regarding toxicities mediated by wild-type EGFR. These results establish Au as a promising option for advanced NSCLC with EGFRm. Clinical trial information: NCT03849768. [Table: see text]

The distinctive characteristics of the micro-vasculature and immune cell infiltration in cystic pancreatic neuroendocrine tumors

PURPOSE

Hypervascularity is a main characteristic of pancreatic neuroendocrine tumors (PanNETs), and cystic PanNETs (CPanNETs) are unique type of PanNETs in which the microenvironment remains unknown. We aim to compare the micro-vasculature features and immune cell infiltration between CPanNETs and solid PanNETs (SPanNETs).

METHODS

Data of 301 SPanNET and 36 CPanNET patients from a high-volume institution were evaluated. CD4, CD8, CD11c, CD15, CD20, CD68, CD34 and α-SMA expression levels were assessed by immunohistochemistry and immunofluorescent double staining. The microvessel density (MVD) and microvessel integrity (MVI) were examined.

RESULTS

MVD and MVI expression levels in CPanNETs were significantly higher than those in SPanNETs (p = 0.025 and 0.0092, respectively). CPanNETs had higher proportions of T1 (p = 0.023) and G1 (p = 0.052) than SPanNETs. In SPanNETs, higher MVD occurred in stages T1, N0 and G1 than in the T2/T3, N1 and G2 subgroups. In CPanNETs, CD34-MVD was uncorrelated with the T stage or grade. Higher CD34-MVD, but not MVI, was associated with better DFS (HR 0.3209, 95% CI 0.1259-0.8176, p = 0.004). There were significantly more peritumoral infiltrating immune cells than their intratumoral counterparts (p < 0.001 for each) in CPanNETs and SPanNETs. The mean number of peritumoral CD68 + TAM in CPanNETs was significantly lower than that in SPanNETs (p = 0.008). The counts of other peritumoral immune cells did not significantly differ between CPanNETs and SPanNETs.

CONCLUSIONS

CPanNETs had a microenvironment distinct from that of SPanNETs, including higher CD34-MVD, higher MVI and lower TAM. This specific microenvironment structure may partially help predicting the prognosis of patients with PanNET.

Tislelizumab Plus Chemotherapy vs Chemotherapy Alone as First-line Treatment for Advanced Squamous Non-Small-Cell Lung Cancer: A Phase 3 Randomized Clinical Trial

Question

Can tislelizumab in combination with chemotherapy offer superior clinical benefit compared with chemotherapy alone as first-line treatment for patients with advanced squamous non–small-cell lung cancer?

Findings

In this phase 3 randomized clinical trial, tislelizumab plus chemotherapy resulted in significant improvement of progression-free survival and objective response rates compared with chemotherapy alone and demonstrated a manageable safety/tolerability profile. In exploratory analyses, neither progression-free survival nor objective response rates were significantly associated with programmed cell death 1 ligand 1 expression.

Meaning

The results of this trial suggest that tislelizumab in combination with chemotherapy is an appropriate first-line treatment option in patients with advanced squamous non–small-cell lung cancer.

Importance

This study demonstrates that tislelizumab in combination with chemotherapy is associated with improved progression-free survival (PFS) in patients with advanced squamous non–small-cell lung cancer (sq-NSCLC).

Objective

To assess the efficacy and safety/tolerability of tislelizumab plus chemotherapy vs chemotherapy alone as first-line treatment for patients with advanced sq-NSCLC.

Design, Setting, and Participants

This open-label, randomized phase 3 clinical trial was conducted at 46 sites in China between July 2018 and June 2019 and included patients with treatment-naive, histologically confirmed stage IIIB/IV sq-NSCLC. The data cutoff for these analyses was December 6, 2019; data extraction occurred on January 7, 2020.

Interventions

Patients were randomized (1:1:1) to receive 1 of the following regimens intravenously on a 21-day cycle: tislelizumab (200 mg, day 1) plus paclitaxel (175 mg/m², day 1) and carboplatin (area under the concentration of 5, day 1) (arm A); tislelizumab plus nab-paclitaxel (100 mg/m², days 1, 8, and 15) and carboplatin (arm B); and paclitaxel and carboplatin (arm C). Patients were stratified by disease stage and tumor programmed cell death 1 ligand 1 (PD-L1) expression (<1% vs 1%-49% vs ≥50%).

Main Outcomes and Measures

The primary end point was progression-free survival (PFS) assessed by an independent review committee (IRC). Secondary end points included overall survival, investigator-assessed (INV) PFS, IRC-assessed objective response rate (ORR), and IRC-assessed duration of response, as well as the incidence and severity of adverse events (AEs).

Results

Overall, 355 patients (median [range] age, 62 [34-74] years; 330 men [91.7%]) with sq-NSCLC received treatment. After a median study follow-up of 8.6 months (95% CI, 8.1-9.0 months), IRC-assessed PFS was significantly improved with tislelizumab plus chemotherapy (arm A, 7.6 months; arm B, 7.6 months) vs chemotherapy alone (arm C, 5.5 months; hazard ratios were 0.524 (95% CI, 0.370-0.742; P < .001 [A vs C]) and 0.478 (95% CI, 0.336-0.679; P < .001 [B vs C]). Higher IRC-assessed ORR and longer IRC-assessed duration of response were observed in arms A (72.5%; 8.2 months) and B (74.8%; 8.6 months) vs C (49.6%; 4.2 months). No association was observed between PD-L1 expression and IRC-assessed PFS or ORR. Discontinuation of any treatment because of AEs was reported in 15 (12.5%; arm A), 35 (29.7%; arm B), and 18 (15.4%; arm C) patients. In each arm, the most common grade of 3 or greater AE was decreased neutrophil levels, which aligned with known chemotherapy toxic effects. Six treatment-related AEs leading to death occurred; however, no deaths were solely attributed to tislelizumab.

Conclusions and Relevance

In this phase 3 randomized clinical trial, adding tislelizumab to chemotherapy was associated with significantly prolonged IRC-assessed PFS, higher IRC-assessed ORRs, and a manageable safety/tolerability profile in patients with advanced sq-NSCLC, regardless of PD-L1 expression.

Trial Registration

ClinicalTrials.gov Identifier: NCT03594747