Clinical benefits of PD-1 inhibitors in specific subgroups of patients with advanced esophageal squamous cell carcinoma: a systematic review and meta-analysis of phase 3 randomized clinical trials.
In recent years, a number of clinical trials have shown that programmed death 1 (PD-1) inhibitors offer significant survival benefits in patients with esophageal squamous cell carcinoma (ESCC). We conducted a meta-analysis to explore the antitumour efficacy of PD-1 inhibitor-based therapy in specific subgroups of patient with advanced ESCC.
We searched for eligible studies from the PubMed, Embase, Web of Science, Cochrane Library databases and conference abstracts. The indicators related to survival outcomes were extracted. The pooled hazard ratios (HRs) for overall survival (OS), progression-free survival (PFS) and duration of response (DOR) and the pooled odds ratio (OR) for objective response rate (ORR) were calculated to evaluate the efficacy of PD-1 inhibitor-based therapy in ESCC. Data regarding treatment lines, treatment regimens, programmed death ligand 1 (PD-L1) status, baseline demographic and disease characteristics were extracted. Subgroup analyses were conducted in specific populations of ESCC patients. The Cochrane risk of bias tool and sensitivity analysis were used to assess the quality of the meta-analysis.
Eleven phase 3 randomized controlled trials (RCTs) involving 6267 patients with ESCC were included in this meta-analysis. Compared with standard chemotherapy, PD-1 inhibitor-based therapy provided benefits in terms of OS, PFS, ORR, and DOR in all populations, the first-line treatment group, the second-line treatment group, the immunotherapy group, and the immunochemotherapy group. Although a limited PFS benefit was observed in second-line treatments and immunotherapy alone, PD-1 inhibitor-based therapy still reduced the risk of disease progression or death. Patients with high PD-L1 expression had a better OS benefit than those with low PD-L1 expression. The HR for OS favoured PD-1 inhibitor-based therapy over standard chemotherapy for all prespecified clinical subgroups.
Compared with standard chemotherapy, PD-1 inhibitor-based therapy exhibited clinically meaningful benefits in patients with ESCC. Survival benefits were better in patients with high PD-L1 expression than in those with low PD-L1 expression, suggesting that the PD-L1 expression level can be used as a predictor of survival benefit from PD-1 inhibitor therapy. PD-1 inhibitor-based therapy provided a consistent benefit in reducing the risk of death according to prespecified subgroup analyses of clinical characteristics.
Lu Y
,Wang W
,Wang F
《Frontiers in Immunology》
Pembrolizumab plus chemotherapy versus chemotherapy alone in patients with advanced non-small cell lung cancer without tumor PD-L1 expression: A pooled analysis of 3 randomized controlled trials.
Pembrolizumab plus platinum-based chemotherapy has demonstrated improved clinical outcomes over chemotherapy alone in patients with previously untreated advanced/metastatic non-small cell lung cancer (NSCLC), regardless of tumor programmed death ligand 1 (PD-L1) expression. This study pooled data from 3 randomized controlled trials to evaluate outcomes with pembrolizumab plus chemotherapy versus chemotherapy alone in patients with advanced/metastatic NSCLC negative for PD-L1 (ie, a tumor proportion score < 1%).
Individual patient data were pooled from KEYNOTE-021 cohort G (nonsquamous; NCT02039674), KEYNOTE-189 (nonsquamous; NCT02578680 and NCT03950674), and KEYNOTE-407 (squamous; NCT02775435). Treatment comprised pembrolizumab plus chemotherapy (pemetrexed and platinum for nonsquamous histology and carboplatin and paclitaxel/nab-paclitaxel for squamous histology) or chemotherapy alone. Responses were assessed according to Response Evaluation Criteria in Solid Tumors version 1.1 by blinded, independent, central review. No α was assigned to this descriptive, exploratory analysis.
Four hundred forty-four of the 1328 patients (33.4%) who were enrolled across the 3 trials had PD-L1-negative tumors (256 on pembrolizumab plus chemotherapy [nonsquamous, n = 155; squamous, n = 94; other, n = 7] and 188 on chemotherapy alone [nonsquamous, n = 83; squamous, n = 99; other, n = 6]). The median time from randomization to the data cutoff was 28.0 months (range, 14.7-55.4 months). Pembrolizumab plus chemotherapy improved overall survival (OS; hazard ratio [HR], 0.63; 95% CI, 0.50-0.79) and progression-free survival (HR, 0.68; 95% CI, 0.56-0.83) over chemotherapy. Sixteen patients in the pembrolizumab plus chemotherapy arm completed 2 years of treatment; the objective response rate was 87.5% (95% CI, 61.7%-98.4%), and the 3-year OS rate was 100%. Adverse events (AEs) were experienced by 99.2% of the patients who received pembrolizumab plus chemotherapy and by 98.9% of the patients who received chemotherapy alone, with grade 3 or higher AEs occurring in 71.4% and 72.0%, respectively; immune-mediated AEs and infusion reactions were experienced by 29.0% and 12.4%, respectively.
Pembrolizumab plus chemotherapy demonstrated response and survival improvements with manageable safety in comparison with chemotherapy alone in PD-L1-negative advanced/metastatic NSCLC, and it is a standard-of-care first-line therapy for patients with advanced NSCLC, regardless of PD-L1 expression.
Some tumors produce a protein called programmed death ligand 1 (PD-L1), which interacts with the body's immune system and prevents an immune response against cancer. Antibody therapies such as pembrolizumab block interactions between tumor PD-L1 and the immune system and enable an immune response. Used alone, pembrolizumab provides benefit for patients with non-small cell lung cancer (NSCLC) tumors that produce PD-L1. However, when it is combined with chemotherapy, which can stimulate anticancer immune responses, pembrolizumab provides a benefit, regardless of tumor PD-L1 production. This article shows that among patients with NSCLC whose tumors produce no PD-L1, outcomes are better with pembrolizumab plus chemotherapy in comparison with chemotherapy alone.
Borghaei H
,Langer CJ
,Paz-Ares L
,Rodríguez-Abreu D
,Halmos B
,Garassino MC
,Houghton B
,Kurata T
,Cheng Y
,Lin J
,Pietanza MC
,Piperdi B
,Gadgeel SM
... -
《-》
Single or combined immune checkpoint inhibitors compared to first-line platinum-based chemotherapy with or without bevacizumab for people with advanced non-small cell lung cancer.
Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis have changed the first-line treatment of people with advanced non-small cell lung cancer (NSCLC). Single-agent pembrolizumab (a PD-1 inhibitor) is currently the standard of care as monotherapy in patients with PD-L1 expression ≥ 50%, either alone or in combination with chemotherapy when PD-L1 expression is less than 50%. Atezolizumab (PD-L1 inhibitor) has also been approved in combination with chemotherapy and bevacizumab (an anti-angiogenic antibody) in first-line NSCLC regardless of PD-L1 expression. The combination of first-line PD-1/PD-L1 inhibitors with anti-CTLA-4 antibodies has also been shown to improve survival compared to platinum-based chemotherapy in advanced NSCLC, particularly in people with high tumour mutational burden (TMB). The association of ipilimumab (an anti CTLA4) and nivolumab (PD-1 inhibitor) has been approved by the US Food and Drug Administration (FDA) in all patients with PD-L1 expression ≥1%. Although these antibodies are currently used in clinical practice, some questions remain unanswered, such as the best-treatment strategy, the role of different biomarkers for treatment selection and the effectiveness of immunotherapy according to specific clinical characteristics.
Primary objective: to determine the effectiveness and safety of first-line immune checkpoint inhibitors (ICIs), as monotherapy or in combination, compared to platinum-based chemotherapy, with or without bevacizumab for people with advanced NSCLC, according to the level of PD-L1 expression.
to maintain the currency of evidence using a living systematic review approach.
We performed an electronic search of the main databases (Cochrane Lung Cancer Group Trial Register, Cochrane Central Register of Controlled Trials, MEDLINE, Embase) from inception until 21 October 2020 and conferences meetings from 2015 onwards.
We included randomised controlled trials (RCTs) reporting on the efficacy or safety of first-line ICI treatment for adults with advanced NSCLC who had not previously received any anticancer treatment. We included trials comparing single- or double-ICI treatment to standard first-line therapy (platinum-based chemotherapy +/- bevacizumab). All data come from 'international multicentre studies involving adults, age 18 or over, with histologically-confirmed stage IV NSCLC who had not received any previous systemic anti-cancer treatment for advanced disease.
Three review authors independently assessed the search results and a fourth review author resolved any disagreements. Primary outcomes were overall survival (OS) and progression-free survival (PFS); secondary outcomes were overall objective response rate (ORR) by RECIST v 1.1, grade 3 to 5 treatment-related adverse events (AEs) (CTCAE v 5.0) and health-related quality of life (HRQoL). We performed meta-analyses where appropriate using the random-effects model for hazard ratios (HRs) or risk ratios (RRs), with 95% confidence intervals (95% CIs), and used the I² statistic to investigate heterogeneity.
Main results We identified 15 trials for inclusion, seven completed and eight ongoing trials. We obtained data for 5893 participants from seven trials comparing first-line single- (six trials) or double- (two trials) agent ICI with platinum-based chemotherapy, one trial comparing both first-line single- and double-agent ICsI with platinum-based chemotherapy. All trials were at low risk of selection and detection bias, some were classified at high risk of performance, attrition or other source of bias. The overall certainty of evidence according to GRADE ranged from moderate-to-low because of risk of bias, inconsistency, or imprecision. The majority of the included trials reported their outcomes by PD-L1 expressions, with PD-L1 ≥ 50 being considered the most clinically useful cut-off level for decision makers. Also, iIn order to avoid overlaps between various PDL-1 expressions we prioritised the review outcomes according to PD-L1 ≥ 50. Single-agent ICI In the PD-L1 expression ≥ 50% group single-agent ICI probably improved OS compared to platinum-based chemotherapy (hazard ratio (HR) 0.68, 95% confidence interval (CI) 0.60 to 0.76, 6 RCTs, 2111 participants, moderate-certainty evidence). In this group, single-agent ICI also may improve PFS (HR: 0.68, 95% CI 0.52 to 0.88, 5 RCTs, 1886 participants, low-certainty evidence) and ORR (risk ratio (RR):1.40, 95% CI 1.12 to 1.75, 4 RCTs, 1672 participants, low-certainty evidence). HRQoL data were available for only one study including only people with PD-L1 expression ≥ 50%, which suggested that single-agent ICI may improve HRQoL at 15 weeks compared to platinum-based chemotherapy (RR: 1.51, 95% CI 1.08 to 2.10, 1 RCT, 297 participants, low-certainty evidence). In the included studies, treatment-related AEs were not reported according to PD-L1 expression levels. Grade 3-4 AEs may be less frequent with single-agent ICI compared to platinum-based chemotherapy (RR: 0.41, 95% CI 0.33 to 0.50, I² = 62%, 5 RCTs, 3346 participants, low-certainty evidence). More information about efficacy of single-agent ICI compared to platinum-based chemotherapy according to the level of PD-L1 expression and to TMB status or specific clinical characteristics is available in the full text. Double-agent ICI Double-ICI treatment probably prolonged OS compared to platinum-based chemotherapy in people with PD-L1 expression ≥50% (HR: 0.72, 95% CI 0.59 to 0.89 2 RCTs, 612 participants, moderate-certainty evidence). Trials did not report data on HRQoL, PFS and ORR according to PD-L1 groups. Treatment related AEs were not reported according to PD-L1 expression levels. The frequency of grade 3-4 AEs may not differ between double-ICI treatment and platinum-based chemotherapy (RR: 0.78, 95% CI 0.55 to 1.09, I² = 81%, 2 RCTs, 1869 participants, low-certainty evidence). More information about efficacy of double-agent ICI according to the level of PD-L1 expression and to TMB status is available in the full text.
Authors' conclusions The evidence in this review suggests that single-agent ICI in people with NSCLC and PD-L1 ≥50% probably leads to a higher overall survival rate and may lead to a higher progression-free survival and overall response rate when compared to platinum-based chemotherapy and may also lead to a lower rate of adverse events and higher HRQoL. Combined ICI in people with NSCLC and PD-L1 ≥50% also probably leads to a higher overall survival rate when compared to platinum-based chemotherapy, but its effect on progression-free survival, overall response rate and HRQoL is unknown due to a lack of data. The rate of adverse events may not differ between groups.
Ferrara R
,Imbimbo M
,Malouf R
,Paget-Bailly S
,Calais F
,Marchal C
,Westeel V
... -
《Cochrane Database of Systematic Reviews》