Early increase of CD103 expression on peripheral PD-1+ CD8+ T cells predicts response to nivolumab in advanced esophageal squamous cell carcinoma.

363 Background: Platinum-based chemotherapy is the standard first-line treatment for advanced or metastatic ESCC. Recently, the combination of PD-(L)1 pathway blockade with chemotherapy has shown synergistic efficacy in a few clinical trials. SHR-1701 is a novel bifunctional fusion protein composed of a mAb against PD-L1 fused with the extracellular domain of TGF-β receptor II. The purpose of this ongoing phase II trial (ChiCTR2000039909) was to evaluate the efficacy and safety of SHR-1701 combined with chemotherapy for unresectable locally advanced, recurrent or metastatic ESCC in China. Methods: This trial enrolled systemic treatment-naive patients(pts) with histologically or cytologically confirmed unresectable locally advanced, recurrent or metastatic ESCC who had ECOG PS of 0-1. Eligible pts received SHR-1701 (30mg/kg, iv, d1, q3w) combined with up to 6 cycles of albumin-bound paclitaxel (125mg/m2, iv, d1, d8, q3w) and cisplatin (75mg/m2, iv, d1, q3w). For those without progressive disease, maintenance treatment was administrated with SHR-1701 monotherapy until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR). Secondary endpoints included progression free survival (PFS), overall survival (OS), disease control rate (DCR), safety and biomarkers. Results: As of September 21, 2022, 18 pts were enrolled. The median age was 67.5 years (range: 46–75 years) and 16 (88.9%) were male. 10 of the pts (55.6%) presented with distant metastasis. 14 pts were included in the efficacy analysis and 17 were in the safety analysis. The ORR and DCR were 85.7% and 100.0%, respectively. One patient achieved a complete response (CR) which will reach confirmation at next visit. 11 pts had partial response (PR), including 9 confirmed PR, one pending confirmation PR, and one unconfirmed PR. In addition, one PR patient got a CR target lesion. Grade 3-4 treatment-related adverse events (AEs) were observed in 23.5% of pts, including neutropenia (11.8%), leukopenia (5.9%), anemia (5.9%), emesis (5.9%) and rash (5.9%). Immune-related AEs (irAEs) were observed in 52.9%, and only one grade 3 irAE of rash occurred. Conclusions: SHR-1701 plus chemotherapy showed potential clinical benefits with acceptable toxicity as first-line treatment, and it might be a favorable option for pts with advanced ESCC. Clinical trial information: ChiCTR2000039909 .

4062 Background: The prognosis of pts with advanced esophageal squamous cell carcinoma (ESCC) remains dismal clinically. Paclitaxel and cisplatin were used as the standard first-line regimen in ESCC for almost two decades. Recently, the combination of PD-1/PD-L1 pathway blockades with chemotherapy has shown synergistic efficacy in a few clinical trials. KN046 is the world's first dual immune checkpoint inhibitor, which can block PD-1/PD-L1 and CTLA-4 pathways at the same time. The purpose of this ongoing phase II trial (NCT03925870) in China was to evaluate the efficacy and safety of KN046 monotherapy or combined with chemotherapy for unresectable locally advanced, recurrent or metastatic ESCC. Methods: This trial included 3 cohorts, one of which enrolled systemic treatment naïve pts with histologically or cytologically confirmed unresectable locally advanced, recurrent or metastatic ESCC who have ECOG PS of 0-1. Eligible subjects were given paclitaxel (135-175mg/m2, iv, d1, q3w) and cisplatin (75mg/m2, iv, d2-4, q3w) plus KN046 (5mpk, iv, d1, q3w) for 4̃6 cycles during initial therapy. For those without progressive disease, maintenance treatment was administrated with KN046 monotherapy (5mpk, iv, q2w) until progression or unacceptable toxicity. Tumour response was assessed according to RECIST 1.1 every 6 weeks. The primary endpoint was investigator-assessed ORR. Secondary endpoints included DCR, safety, PK profile, and immunogenicity. Results: As of December 14, 2020, 15 pts were enrolled, all of them were male, 52.3% ≥60 years, 64% ECOG 1, 80% with distant metastasis. Median exposure time to KN046 was 11.4 wks and average KN046 treatment was 2.4 cycles. 12 pts were included in the efficacy analysis and 15 pts in the safety analysis. The overall response rate (ORR) and disease control rate (DCR) were 58.3% and 91.6%, respectively. 7 pts (58.3%) had partial response (PR) including one complete response of target lesion. 4 pts (33.3%) had stable disease (SD) with 3 pts showing more than 20% of tumor burden reduction. The overall incidence of KN046 related adverse events was 80.0%, with 13.3% Gr 3 or above TRAE. Infusion-related adverse events occurred during 7.8% and most were mild. Immune related adverse events（irAE）were seen in 53.3% and the most common Gr 3 irAE were nausea (n＝1, 6.7%) and rash (n＝1, 6.7%). Conclusions: KN046 plus paclitaxel/cisplatin demonstrated clinical efficacy and acceptable safety as first-line treatment, and might be a favorable option for pts with advanced ESCC. Clinical trial information: NCT03925870. Research Sponsor: Jiangsu Alphamab Biopharmaceuticals Co., Ltd. Clinical trial information: NCT03925870.

215 Background: Esophageal squamous cell carcinoma (ESCC) is a lethal cancer with a high unmet medical need. Camrelizumab, an anti-PD-1 monoclonal antibody, significantly improved overall survival (OS) and objective response rate (ORR) in Chinese patients (pts) with advanced ESCC compared with chemotherapy, with a manageable safety profile in phase III randomized trial (ESCORT). However, the absolute long-term survival benefiting from PD-1 inhibitors is limited, and new effective treatments are needed. Here, our study aimed to assess the efficacy and safety of combination with camrelizumab and apatinib (VEGFR2 inhibitor) as second-line treatment for advanced ESCC. Methods: This ongoing phase II trial (NCT03736863) in six sites in China enrolled pts aged 18-75 with unresectable locally advanced, locally recurrent, or metastatic ESCC that progressed or were intolerant after first-line chemotherapy, and an ECOG performance status of 0-1. Pts received 200 mg intravenous camrelizumab every two weeks plus 250 mg oral apatinib daily in 4-week cycles until disease progression, unacceptable adverse events (AEs) or withdrawal of consent. The primary endpoint was investigator-assessed ORR. Secondary endpoints included disease control rate (DCR), progression-free survival (PFS) and OS. Results: At data cutoff (Sept 11, 2020), 36 pts were enrolled, 7 females and 29 males, and 25 pts had lymph node metastases. Twelve pts received radiotherapy and 25 underwent surgery. Twenty-five pts were included in the efficacy analysis with median follow-up time of 5.0 months and 36 pts in the safety analysis with median follow-up time of 4.6 months. The primary endpoint ORR without confirmation was 40 % with complete response in two pts (8%) and partial response in eight pts (32%). Thirteen pts (52%) had stable disease, and the DCR was 92%. The median PFS and OS were not reached. A total of 72.2% of pts had AEs, and 30.6% of pts experienced grade 3 AEs. The most common AEs (all grade, grade≥3) were elevated aspartate aminotransferase (30.6%, 19.4%), elevated alanine aminotransferase (30.6%, 13.9%), hypertension (25%, 2.8%),neutrophil (25%, 5.6%), thrombocytopenia (25%, 0%), leukopenia (22.2%, 2.8%), anemia (11.1%, 0%), proteinuria (11.1%, 0%), hematochezia (8.3%, 0%), reactive cutaneous capillary endothelial proliferation (5.6%, 2.8%), pruritus (5.6%, 0%), esophageal fistula (5.6%, 0%), fatigue (2.8%, 0%) and hypothyroidism (2.8%, 0%). Conclusions: This is the first study to explore the combination of PD-1 inhibitor and anti-angiogenesis inhibitor as a second-line treatment for advanced ESCC. Camrelizumab plus apatinib demonstrated encouraging clinical efficacy and acceptable safety as second-line treatment, and might be a favorable option for pts with advanced ESCC. Further phase III randomized trials are warranted. Clinical trial information: NCT03736863.

e16013 Background: Paclitaxel combined with cisplatin regimen has been the standard first-line therapy in advanced Esophageal Squamous Cell Carcinoma (ESCC) for almost two decades. However, the 5-year survival rate was only 4.8% in advanced ESCC. Therefore, more effective therapeutic treatments were needed to prolong the survival urgently. Anlotinib was demonstrated to be an effective second-line monotherapy for patients with advanced or recurrent ESCC in China. And the preliminary results of our trial had been reported in 2020 ESMO (Abs 1448) and 2021 ASCO-GI Symposium (Abs 181). Consequently, this study was to investigate the efficacy and safety of paclitaxel and cisplatin combined with anlotinib as first-line therapy in advanced ESCC and report the update results regularly. Methods: Pts with previously untreated metastatic or unresectable, locally advanced ESCC, who had not received (neo) adjuvant therapy/radical surgery within 6 months were recruited in this study. Eligible patients were given paclitaxel (135mg/m2, iv, q3w) and cisplatin (60̃75mg/m2, iv, d1̃3, q3w) plus anlotinib (10mg, po, d1̃14, q3w) for 4̃6 cycles as initial therapy. For those who did not have disease progression, maintenance treatment was treated with anlotinib monotherapy (10mg, po, d1̃14, q3w) until progression or unacceptable toxicity. The tumor response was assessed by investigator according to RECIST version 1.1 criteria using computed tomography scans every two cycles. The predefined sample size was 47. The primary endpoint was PFS and secondary endpoints included safety, ORR, DCR and DOR. Results: From Oct 2019 to Dec 2020, a total of 45 patients were enrolled. Among 34 pts who were available for efficacy and safety evaluation. there were 1 confirmed CR (2.9%), 26 confirmed PR (76.5%), 2 unconfirmed PR (5.9%) and 5 SD (14.7%). Consequently, ORR was 79.4% (95%CI: 62.1̃91.3) and DCR was 100.0% (95%CI: 89.7̃100.0). At the data cut-off date, 11 patients discontinued treatment due to PD, the preliminary prognostic result indicated that the median PFS of the 34 patients was 9.76 months (95%CI: 8.44-13.08). And the median OS was not yet available. Additionally, safety profile exhibited that the common drug-related adverse events were myelosuppression, gastrointestinal reaction, fatigue, hypertension, constipation, hypokalemia, hepatotoxicity and hemoptysis. And the common grade ≥3 adverse events were myelosuppression (20.6%), hypertension (8.8%), nausea and vomit (5.9%), fatigue (5.9%) and hypokalemia (5.9%). Conclusions: The update results suggested that the regimen of paclitaxel and cisplatin combined with anlotinib as first-line therapy for advanced ESCC exhibited encouraging efficacy and tolerable safety profile. And the conclusions needed to be confirmed in trials continued subsequently. Clinical trial information: NCT04063683.

181 Background: The prognosis of pts with advanced ESCC remains dismal clinically. Paclitaxel and cisplatin were used as the standard first-line regimen in ESCC for almost two decades. As a novel multitarget tyrosine kinase inhibitor mainly targeting antiangiogenic single pathway, anlotinib was demonstrated to be an effective second-line monotherapy for pts with advanced or recurrent ESCC in China. Consequently, the aim of this study was to investigate the efficacy and toxicity of paclitaxel and cisplatin combined with anlotinib as first-line therapy for advanced ESCC. Methods: Pts with previously untreated metastatic or unresectable, locally advanced ESCC, who had not received (neo) adjuvant therapy/radical surgery within 6 months were recruited in this study. Eligible subjects were given paclitaxel (135mg/m2, iv, q3w) and cisplatin (60~75mg/m2, iv, d1~3, q3w) plus anlotinib (10mg, po, d1~14, q3w) for 4~6 cycles during initial therapy. For those without progressive disease, maintenance treatment was administrated with anlotinib monotherapy (10mg, po, d1~14, q3w) until progression or unacceptable toxicity. The tumor response was assessed by investigator according to RECIST version 1.1 using CT scans every two cycles. And the calculated sample size of this study was 47. The primary endpoint was PFS, secondary endpoints were safety, objective response rate (ORR), disease control rate (DCR) and duration of response (DOR). Results: From Oct 2019 to Aug 2020, 27 pts were available for efficacy and safety evaluation. In best overall response assessment, there were 7.4% CR (2/27), 66.7% PR (18/27) and 25.9% SD (7/27). ORR was 74.1% (95%CI: 53.7. ~ 88.9), and DCR was 100.0% (95%CI: 87.2~100.0). The median PFS of the 27 pts was not yet available. The safety profile indicated that the most common drug-related adverse events were myelosuppression, gastrointestinal reaction, fatigue, hypertension, constipation, hypokalemia and hepatotoxicity. The common grade 3-4 treatment-related adverse events were myelosuppression (18.5%), hypertension (7.4%). Conclusions: The current results indicated that paclitaxel and cisplatin combined with anlotinib as first line therapy for advanced ESCC exhibited encouraging efficacy and manageable adverse events. The conclusion should be validated in more pts consecutively. Clinical trial information: NCT04063683. [Table: see text]

4035 Background: NIVO + chemo and NIVO + IPI demonstrated significant overall survival (OS) benefit vs chemo in previously untreated patients (pts) with advanced ESCC in the phase 3 CheckMate 648 study. We report expanded results from the primary analysis with 13-month (mo) minimum follow-up. Methods: Pts with previously untreated, unresectable advanced, recurrent, or metastatic ESCC were randomized to NIVO (240 mg Q2W) + chemo (fluorouracil + cisplatin Q4W), NIVO (3 mg/kg Q2W) + IPI (1 mg/kg Q6W), or chemo. Primary endpoints were OS and progression-free survival (PFS) per blinded independent central review (BICR) in pts with tumor cell programmed death ligand 1 (PD-L1) ≥ 1%. Secondary endpoints planned for hierarchical testing included OS, PFS, and objective response rate (ORR) per BICR in all randomized pts. Duration of response (DOR) per BICR and PFS2 per investigator (time from randomization to progression after subsequent systemic therapy, initiation of second subsequent systemic therapy, or death) were exploratory endpoints. Results: Among all pts randomized to NIVO + chemo (n = 321), NIVO + IPI (n = 325), or chemo (n = 324), PFS2 favored NIVO + chemo (HR 0.64, 95% CI 0.54–0.77) and NIVO + IPI (HR 0.74, 95% CI 0.62–0.88) vs chemo. ORR (95% CI) was 47% (42–53), 28% (23–33), and 27% (22–32), respectively. More responders with NIVO + chemo or NIVO + IPI vs chemo had prolonged DOR (≥12 mo; 39%, 48%, and 23%, respectively). Efficacy data by tumor cell PD-L1 and PD-L1 combined positive score will be presented. Grade 3/4 treatment-related adverse events with potential immunologic etiology (select TRAEs) occurred in ≤ 6% of pts with NIVO + chemo and NIVO + IPI, and non-endocrine select TRAEs resolved in 57%–95% of pts across organ categories (Table). Conclusions: NIVO + chemo and NIVO + IPI demonstrated favorable PFS2 and a higher proportion of pts with prolonged DOR vs chemo, as well as acceptable safety profiles. These results provide further support for each regimen as a new potential 1L standard of care in advanced ESCC. Clinical trial information: NCT03143153. [Table: see text]

364 Background: The optimal therapies for patients with advanced esophageal squamous cell carcinoma (ESCC) who have progressed after immune checkpoint inhibitors (ICIs) are unclear. This phase II single-arm study aimed to assess the efficacy and safety of re-challenge with camrelizumab plus apatinib in this population. Methods: This study enrolled patients with unresectable locally advanced, locally recurrent, or metastatic ESCC who had experienced prior progression on ICI treatment. Enrolled patients received camrelizumab 200 mg intravenously every two weeks along with daily oral apatinib 250 mg. Treatment continued until disease progression, unacceptable toxicity, or patient withdrawal of consent. The primary endpoint was the confirmed objective response rate (ORR). Secondary endpoints included disease control rate (DCR), duration of response (DOR), time to response (TOR), progression-free survival (PFS), overall survival (OS), 3- and 6-month PFS rates, 6-, 9- and 12-month OS rates, and safety. Results: From September 1, 2021, to March 29, 2023, 49 eligible patients were enrolled and given treatment. Among 38 treated patients who had at least one post-baseline efficacy measurement, the ORR and confirmed ORR were 36.8% (95% CI 21.8–54.0) and 13.2% (95% CI 4.4–28.1); the DCR was 89.5% (95% CI 75.2–97.1); the median DOR was 3.0 months; and the median TOR was 2.2 months. Among the 49 treated patients, the median PFS was 4.6 months (95% CI 3.8–6.5) and OS was 7.5 months (95% CI 5.5–13.6). Patients who were both PD-L1 positive and had responded to previous ICI therapy had the longest median PFS (5.7 months, 95% CI 3.9–not reached) and OS (9.6 months, 95% CI 7.5–not reached). Grade ≥ 3 treatment-related adverse events occurred in 34.7% of patients (17/49). Conclusions: This study showed promising efficacy and an acceptable safety profile of camrelizumab plus apatinib for patients with advanced ESCC who had progressed after ICI therapy. The subset of patients who were both PD-L1 positive and had a prior ICI response seemed to benefit most. Clinical trial information: NCT03736863 .

411 Background: Recently, several clinical trials have demonstrated synergistic efficacy by combining immune checkpoint inhibitors (ICIs) with chemotherapy. However, only a subset of patients (pts) derived benefits. Combining ICIs with agents blocking immunosuppressive pathway may expand the clinical benefit of ICIs to more pts. Transforming growth factor β (TGF-β) participates in tumor immune escape. SHR-1701, a novel bifunctional fusion protein consisting of a monoclonal antibody targeting PD-L1 fused with the extracellular domain of TGF-β receptor II, was evaluated in a phase II trial (ChiCTR2000039909) to assess its efficacy and safety when combined with chemotherapy for pts with unresectable locally advanced, recurrent or metastatic ESCC in China. Methods: This trial enrolled treatment-naive pts with histologically or cytologically confirmed unresectable locally advanced, recurrent, or metastatic ESCC. Eligible pts received SHR-1701 (30mg/kg, iv, d1, q3w) in combination with up to six cycles of albumin-bound paclitaxel (125mg/m 2 , iv, d1, d8, q3w) and cisplatin (75mg/m 2 , iv, d1, q3w). For those without progressive disease, maintenance treatment was administered with SHR-1701 monotherapy until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR). Secondary endpoints included progression-free survival (PFS), overall survival (OS), disease control rate (DCR) and safety. Results: At the data cut-off, March 1, 2024, 24 pts had received at least one dose of the study treatment and were included in both the intention-to-treat (ITT) analysis and safety analysis sets. 3 and 12 pts achieved confirmed complete and partial responses, respectively. The confirmed ORR was 62.5% and DCR was 87.5%. With a median follow-up of 20.8 months (95% CI, 15.5-NR), the median duration of response was 9.1 months (95% CI, 6.9-NR). The median PFS was 10.8 months (95% CI, 7.8-NR) and the median OS was 26.1 months (95% CI, 8.6-NR). 12-month PFS and OS rates were 41.4% (95% CI, 22.5-76) and 64.8% (95% CI, 47.8-87.9), respectively. Grade 3-4 treatment-related adverse events occurred in 11 (45.8%) pts and no treatment-related death was observed. Conclusions: The results highlighted that SHR-1701 plus chemotherapy as first-line therapy maintained long-term, durable survival benefit in pts with advanced ESCC. Clinical trial information: ChiCTR2000039909.

384 Background: CAP 02 study (NCT03736863) is a single-arm phase 2 study to evaluate the efficacy and safety of camrelizumab plus apatinib (a VEGFR2 inhibitor) as second-line treatment in patients with advanced esophageal squamous cell carcinoma (ESCC). Cohort 1 has been published recently, which enrolled patients who progressed after or were intolerant to first-line chemotherapy. The results showed an encouraging median overall survival (OS) of 15.8 months. Here, we reported the preliminary results of cohort 2. Methods: Cohort 2 enrolled unresectable locally advanced, locally recurrent, or metastatic ESCC patients aged 18-75 years with ECOG performance status of 0-1 who had progression on or were intolerant to first-line immunochemotherapy. The disease should be controlled without progression for at least three months during the first-line treatment. Patients received camrelizumab (200 mg Q2W) and apatinib (250 mg QD) until disease progression, intolerable toxicity, or withdrawal for other reasons. The primary endpoint was the objective response rate (ORR). Secondary endpoints included disease control rate, progression-free survival (PFS), duration of response, time to response, OS, 3/6-month PFS rates, 6/9/12-month OS rates, and safety. Results: At the data cutoff (Sep 21, 2022), 33 of the planned 40 patients with an average of 68 years old had been enrolled, including 24 (73%) males and 24 (73%) patients with an ECOG PS score of 1. Twenty-one patients (64%) were previously treated with camrelizumab combined chemotherapy and 12 with other immunochemotherapy. Among the 17 evaluable patients, seven had the best overall response of partial response and nine with stable disease; the ORR was 41%. A total of 22 patients (67%) had treatment-related adverse events (TRAEs), with 12 patients (36%) with grade≥3. The most common TRAEs included white blood cell count decreased (11 patients, 33%), hypokalaemia (9, 27%), and alanine aminotransferase increased (8, 24%). Conclusions: Current results suggested the preliminary efficacy of second-line camrelizumab plus apatinib in patients with immunochemotherapy-treated advanced ESCC, with an acceptable safety profile. The study enrollment is ongoing, and further survival and safety data will be reported in the future. Clinical trial information: NCT03736863 .

Chemotherapy options for patients with advanced esophageal cancer had been limited until immune checkpoint inhibitors (ICIs) were approved for this indication. In recent years, ICI alone and ICI-combined chemotherapy have been approved, which prolonged the overall survival (OS) of patients with advanced esophageal cancer. We retrospectively analyzed 265 patients with unresectable advanced, recurrent, or metastatic esophageal squamous cell carcinoma (ESCC) who received chemotherapy with and without ICIs at Tohoku University Hospital from January 2013 to March 2022. Cisplatin plus fluorouracil therapy was the most frequently administered regimen as first-line treatment, and their administration frequency did not significantly differ between before 2019 and after 2020. Nivolumab was the most frequently used treatment as second-line therapy since its first approval in 2020 (74%), whereas taxanes were the most frequently used regimen before 2019 (55%). The median OS was 13.9 months over the entire observation period. Among patients who received second-line therapy, those receiving ICIs at any line demonstrated significantly longer OS from the start of second-line treatment than the others (p = 0.03). Univariate analysis revealed that a G8 score of < 11 (hazard ratio: 1.62, p = 0.02) was a prognostic factor in patients aged ≥ 65 years. Among each components of the G8 score, a decrease in food intake, weight loss, impaired mobility, and self-perceived poor health status were shown to be particularly associated with shorter OS. Our real-world data demonstrated that ICI administration contributed to improved OS after initiating second-line treatment for unresectable, advanced, or recurrent ESCC. Additionally, we revealed that the G8 score could be a useful prognostic factor in elderly patients with advanced ESCC treated with chemotherapy.

Adding immune checkpoint inhibitors (ICIs) to the chemotherapy has shown significant clinical benefits in neoadjuvant treatment of locally advanced esophageal squamous cell carcinoma (ESCC). Sintilimab is one such ICI used for treatment. Herein, we designed a trial to evaluate the safety and efficacy of sintilimab combined with paclitaxel and platinum for locally advanced resectable ESCC. Patients with locally advanced resectable (stage II-III) ESCC were enrolled and received at least two cycles of neoadjuvant therapy with sintilimab (200 mg on day 1) plus platinum-based chemotherapy in each 3-week cycle followed by esophagectomy. The primary endpoint of the trial was the pathological complete response (pCR) rate. The secondary endpoints were the major pathological response (MPR) rate, the objective response rate (ORR), the treatment-related adverse events (TRAEs), the immune-related adverse events (irAEs) and quality of life (QOL). Besides, relapse-free survival (RFS), overall survival (OS) were exploratory endpoints. Forty-three cases were needed to be enrolled in this trial. It was assumed the regimen of the neoadjuvant sintilimab plus chemotherapy would achieve a pCR rate of 30.5%. Between March 2021 and January 2023, a total of 43 patients (41 men and 2 women) were enrolled, including 11 cases (25.6%) of clinical stage II and 32 cases (74.4%) of clinical stage III at baseline. All the 43 patients completed two cycles of neoadjuvant therapy, and 32 patients received McKeown radical resection for esophageal cancer. The pCR rate was 28.1% (9/32), which was below the 30.5% reference cutoff value, and the MPR rate was 37.5% (12/32). According to RECIST 1.1, four patients (4/43, 9.3%) had a complete response (CR), 21 patients (21/43, 48.8%) had a partial response (PR), ORR was 58.1% (25/43). The incidence of ≥ grade 3 TRAEs was 23.3% (10/43) and there were no ≥ grade 4 TRAEs. Sintilimab plus platinum-based chemotherapy as neoadjuvant therapy is safe, feasible and effective in locally advanced resectable ESCC, suggesting a supportive rationale for its further evaluation in randomized clinical trials. Chinese Clinical Trial Registry identifier: ChiCTR2200056558.

Efficacy and safety of camrelizumab plus apatinib in patients with advanced esophageal squamous cell carcinoma previously treated with immune checkpoint inhibitors (CAP 02 Re-challenge): A single-arm, phase II study

LBA4001 Background: NIVO demonstrated superior overall survival (OS) vs chemo in previously treated patients (pts) with ESCC (ATTRACTION-3). We report OS and progression-free survival (PFS) from CheckMate 648, the first global phase III study to evaluate both an immuno-oncology (I-O)/chemo combination and an I-O/I-O combination in advanced ESCC. Methods: Adults with previously untreated, unresectable advanced, recurrent or metastatic ESCC were enrolled regardless of tumor cell PD-L1 expression. Pts were randomized to NIVO (240 mg Q2W) + chemo (fluorouracil + cisplatin Q4W), NIVO (3 mg/kg Q2W) + IPI (1 mg/kg Q6W), or chemo alone. Primary endpoints for both comparisons were OS and PFS per blinded independent central review (BICR) in pts with tumor cell PD-L1 ≥ 1%. Hierarchically tested secondary endpoints included OS and PFS in all randomized pts. Results: 970 pts were randomized to NIVO + chemo, NIVO + IPI, and chemo arms (49% with tumor cell PD-L1 ≥ 1%). With 13 months (mo) minimum follow-up, NIVO + chemo and NIVO + IPI led to statistically significant improvement in OS vs chemo in pts with tumor cell PD-L1 ≥ 1% and all randomized pts (Table). Statistically significant PFS benefit was also observed for NIVO + chemo vs chemo (HR 0.65 [98.5% CI 0.46–0.92]; P = 0.0023) in pts with tumor cell PD-L1 ≥ 1%. PFS in NIVO + IPI vs chemo in pts with tumor cell PD-L1 ≥ 1% did not meet the prespecified boundary for significance. The objective response rate (per BICR) was 53% (NIVO + chemo), 35% (NIVO + IPI), and 20% (chemo) in pts with tumor cell PD-L1 ≥ 1% and in all randomized pts was 47%, 28%, and 27%, respectively; longer median (95% CI) duration of response was observed vs chemo for pts with tumor cell PD-L1 ≥ 1%: 8.4 (6.9–12.4), 11.8 (7.1–27.4), and 5.7 (4.4–8.7) mo and for all randomized pts: 8.2 (6.9–9.7), 11.1 (8.3–14.0), and 7.1 (5.7–8.2) mo, respectively. No new safety signals were identified (Table). Conclusions: NIVO plus chemo and NIVO plus IPI both demonstrated superior OS vs chemo, along with durable objective responses and acceptable safety, in pts with advanced ESCC, and each represents a potential new 1L treatment option. Clinical trial information: NCT03143153. [Table: see text]

BackgroundThe standard treatment for elderly patients with unresectable locally advanced esophageal squamous cell carcinoma (ESCC) is definitive chemoradiotherapy with S-1. However, the 3-year overall survival (OS) is limited to approximately 40%. Tislelizumab is the first- and second-line standard treatment for advanced ESCC with tolerable toxicity. In this study, we aimed to explore a new curative strategy for locally advanced unresectable ESCC in the elderly by combining tislelizumab with chemoradiotherapy.MethodsThis study is an open-label, multicenter, investigator-initiated phase II clinical trial in older patients with inoperable locally advanced ESCC evaluating tislelizumab plus concurrent chemoradiotherapy compared with concurrent chemoradiotherapy. The main inclusion criteria were pathological confirmation of locally advanced inoperable ESCC at clinical cT1N2-3M0 or cT2-4bN0-3M0 (stage II–IVA), age ≥ 70 years, absence of previous systemic anti-tumor therapy, and adequate organ function. A total of 136 patients will be recruited from approximately seven centers (in Tianjin, Chengdu, Taiyuan, Zhengzhou, Shijiazhuang, Changsha, Nanjing) over a period of 18 months and randomized in a 1:1 ratio to receive tislelizumab in combination with concurrent chemoradiotherapy (tislelizumab + S-1 + radiotherapy) or concurrent chemoradiotherapy (S-1 + radiotherapy). The efficacy and safety of the treatment will be evaluated during the therapy and follow-up period until disease progression, death, or the end of the trial. The primary study endpoint was investigator-assessed progression-free survival (PFS), and secondary study endpoints were OS, objective response rate (ORR), duration of remission (DOR), and safety. Fresh or archival tumor tissues and peripheral blood samples will be used in exploratory studies.DiscussionThis study is the first “programmed death-1 (PD-1) inhibitor combined with concurrent chemoradiotherapy” for elderly patients with inoperable locally advanced ESCC (NCT06061146). The synergistic efficacy of combined definitive concurrent chemoradiotherapy with tislelizumab is expected to result in survival benefits for elderly patients with inoperable locally advanced ESCC. Because S-1 plus concurrent radiotherapy is the standard treatment option for locally advanced ESCC in older patients, the combination of definitive concurrent chemoradiotherapy and tislelizumab has the potential to change the standard ESCC therapeutic strategy with comparable safety.Trial registrationClinicalTrials.gov NCT06061146.Registered 9/10/2023.

O-3 Nivolumab (NIVO) plus chemotherapy (chemo) or ipilimumab (IPI) vs chemo as first-line treatment for advanced esophageal squamous cell carcinoma (ESCC): Expanded efficacy and safety analyses from CheckMate 648