Progression-free survival at 3 years is a reliable surrogate for 5-year overall survival for patients suffering from locally advanced esophageal squamous cell carcinoma

A Surrogate Endpoint for Overall Survival in Locally Advanced and Resectable Esophageal Squamous Cell Carcinoma: A Reanalysis of Data From the NEOCRTEC5010 Trial

PURPOSE

This study aimed to investigate disease-free survival (DFS) as a surrogate endpoint for overall survival (OS) in patients with locally advanced and resectable esophageal squamous cell carcinoma.

METHODS AND MATERIALS

We re-analyzed patient data from the NEOCRTEC5010 randomized controlled trial (N = 451 patients) to compare their OS with that of an age- and sex-matched cohort from the general population of China. We used expected survival and the standardized mortality ratio, respectively, in our analysis of data collected from a neoadjuvant chemoradiation therapy (NCRT) plus surgery group and a surgery-only group. Published data from 6 randomized controlled trials and 20 retrospective studies were used to examine the correlation between DFS and OS at the trial level.

RESULTS

The annual hazard rate of disease progression decreased to 4.9% and 8.1% within 3 years in the NCRT and surgery groups, respectively. Patients who were disease-free at 36 months had a 5-year OS of 93.9% (95% CI, 89.7%-98.4%) in the NCRT group with a standardized mortality ratio of 1.1 (95% CI, 0.7-1.8; P = .5639). In contrast, the 5-year OS was only 12.9% (95% CI, 7.3%-22.6%) for patients in the NCRT group who exhibited disease progression within 36 months. At the trial level, DFS and OS were correlated with treatment effect (R2 = 0.605).

CONCLUSIONS

Disease-free status at 36 months is a valid surrogate endpoint for 5-year OS in patients with locally advanced and resectable esophageal squamous cell carcinoma. Patients who were disease-free at 36 months showed a favorable OS, which was indistinguishable from that of the age- and sex-matched comparison group from the general population; otherwise, their 5-year OS was extremely poor.

Difference in Efficacy and Safety of Anti-CD19 Chimeric Antigen Receptor T-Cell Therapy Containing 4-1BB and CD28 Co-Stimulatory Domains for B-Cell Acute Lymphoblastic Leukemia

This study quantified the differences in the efficacy and safety of different stimulation domains of anti-CD19 chimeric antigen receptor (CAR) T therapy for B-cell acute lymphoblastic leukemia (B-ALL). Clinical trials related to anti-CD19 CAR T-cell therapy for B-ALL were searched in public databases from database inception to 13 November 2021. The differences in overall survival (OS) and progression-free survival (PFS) of B-ALL patients treated with anti-CAR T-cell therapy containing 4-1BB and CD28 co-stimulatory domains were compared by establishing a parametric survival function. The overall remission rate (ORR), the proportion of people with minimal residual disease (MRD)-negative complete remission (CR), the incidence of cytokine release syndrome (CRS), and the neurotoxicity across different co-stimulatory domains was assessed using a random-effects model. The correlation between the ORR, MRD-negative CR, PFS, and OS was tested. The results showed that the median OS of anti-CAR T-cell treatment containing 4-1BB and CD28 co-stimulatory domains was 15.0 months (95% CI: 11.0-20.0) and 8.5 months (95% CI: 5.0-14.0), and the median PFS was 7.0 months (95% CI: 4.0-11.5) and 3.0 months (95% CI: 1.5-7.0), respectively. Anti-CD19 CAR T-cells in the 4-1BB co-stimulatory domain showed superior benefits in patients who achieved ORR. The incidence of neurotoxicity was significantly higher in the CD28 co-stimulatory domain of anti-CD19 CAR T-cells than in the 4-1BB co-stimulatory domain. In addition, the ORR and MRD-negative CR were strongly correlated with OS and PFS, and PFS and OS were strongly correlated. The 4-1BB co-stimulatory domain suggested a better benefit-risk ratio than the CD28 co-stimulatory domain in B-ALL.

Identification on surrogating overall survival with progression-free survival of first-line immunochemotherapy in advanced esophageal squamous cell carcinoma-an exploration of surrogate endpoint

BACKGROUND

Overall survival (OS) is the gold standard to assess novel therapeutics to treat cancer. However, to identify early efficacy and speed up drug approval, trials have used progression-free survival (PFS) as a surrogate endpoint (SE). Herein, we aimed to examine if PFS could function as an OS surrogate in advanced Esophageal Squamous Cell Carcinoma (ESCC) treated with first-line immunochemotherapy.

METHODS

Two hundred ninety-two advanced ESCC patients treated using inhibitors of PD-1/PD-L1 + chemotherapy or chemotherapy alone were collected. In addition, six phase III randomized clinical trials were eligible for inclusion. Bayesian normal-induced-copula-estimation model in retrospective patient data and regression analysis in the published trial data were used to determine the PFS-OS correlation.

RESULTS

PFS correlated moderately with OS in the retrospective cohort (Kendall's Tau = 0.684, τ = 0.436). In trial-level, treatments effects for PFS correlated weakly with those for OS in intention-to-treat population (R² = 0.436, adj.R² = 0.249, P > 0.05) and in PD-L1-enriched population (R² = 0.072). In arm-level, median PFS also correlated weakly with median OS. Moreover, analysis of the retrospective cohort demonstrated that the annual death risk after progression in the continued immunotherapy group was considerably lower than that in the discontinued group.

CONCLUSION

In trials of anti-PD-1 agents to treat advanced ESCC, the current results provide only weak support for PFS as an OS surrogate; OS cannot be substituted completely by PFS in these cases. The results also suggest that qualified patients with advanced ESCC might benefit from continuous immunotherapy beyond progression to achieve a decreased risk of death.

Comparative efficacy and safety of immunotherapy for patients with advanced or metastatic esophageal squamous cell carcinoma: a systematic review and network Meta-analysis

Background

The study aimed to compare efficacy and safety of various immune checkpoint inhibitors for patients with advanced or metastatic esophageal squamous cell carcinoma (ESCC).

Methods

We searched Medline, Web of Science, Cochrane Central Register of Controlled Trials, Embase, Clinical Trials.gov and several international conference databases from January 1, 2000 to December 19, 2021. We conducted Bayesian network meta-analysis to assess the relative effects among treatments. Outcomes included overall survival (OS), progression-free survival (PFS), overall response rate and adverse events.

Results

Ten eligible trials with 5250 patients were included. Toripalimab and Camrelizumab plus chemotherapy were preferred to rank first on OS (probability, 61%) and PFS (probability, 37%) in the first-line setting, respectively. In refractory patients, Sintilimab and Camrlizumab were most likely to be ranked first on OS (probability, 37%) and PFS (probability, 94%). The toxicity related to immunotherapy was manageable in clinical trials. Camrelizumab and Nivolumab had the less adverse events of grade 3 or higher in the first and refractory setting, respectively.

Conclusions

This study found that Toripalimab and Camrelizumab plus chemotherapy were likely to be the best option in terms of OS and PFS in the first-line setting for patients with advanced or metastatic ESCC respectively. Sintilimab and Camrelizumab were the preferred options for OS and PFS in refractory patients respectively. The toxicity of immunotherapy was different from conventional chemotherapy, but manageable in patients with ESCC.

Trial registration

PROSPERO registration number: (CRD 42021261554).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-10086-5.