Clinical Activity of Neoadjuvant Camrelizumab/Chemotherapy Combination in Locally Advanced Esophageal Squamous Cell Carcinoma
Neoadjuvant camrelizumab in combination with nab-paclitaxel and cisplatin exhibited enhanced pathological complete response compared to solitary chemotherapy in individuals diagnosed with esophageal squamous cell carcinoma.
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The neoadjuvant amalgamation of camrelizumab, nab-paclitaxel (Abraxane), and cisplatin demonstrated statistically significant enhancements in pathologic complete responses (pCRs) compared to solitary chemotherapy in individuals diagnosed with resectable locally advanced esophageal squamous cell carcinoma (LA-ESCC), according to results from the phase 3 ESCORT-NEO/NCCES01 trial (ChiCTR2000040034) that were presented at the 2024 Gastrointestinal Cancers Symposium.1
Results showed that the pCR rate in the intention-to-treat (ITT) population given camrelizumab with nab-paclitaxel and cisplatin (n = 132) was 28.0% (95% CI, 20.6%-36.5%) compared with 15.4% (95% CI, 9.7%-22.8%) with camrelizumab plus paclitaxel/cisplatin (n = 130) and 4.7% (95% CI, 1.7%-9.8%) with paclitaxel/cisplatin (n = 129). This translated to a 23.5% difference between the camrelizumab/nab-paclitaxel/cisplatin and chemotherapy-alone arms (95% CI, 15.1%-32.0%; P<.0001) and a 10.9% difference between the camrelizumab/paclitaxel/cisplatin and chemotherapy-alone arms (95% CI, 3.7%-18.1%; P = .0034). The odds ratios were 8.11 (95% CI, 3.28-20.06) and 3.81 (95% CI, 1.48-9.80), respectively.
“ESCORT-NEO/NCCES01 is the first phase 3 trial evaluating neoadjuvant immunotherapy plus chemotherapy vs chemotherapy for LA-ESCC,” Yin Li, MD, of the Department of Thoracic Surgery, National Cancer Center/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, in Beijing, China, said in a presentation during the meeting. “Camrelizumab plus chemotherapy significantly improved pCR rates in the ITT population, with a consistent trend of improvement across subgroups. Neoadjuvant camrelizumab plus chemotherapy may hold promise as a potential standard of care [in] the neoadjuvant treatment for LA-ESCC.”
Globally, esophageal cancer is the seventh most common malignancy, and Li noted that there is an unmet need for novel therapies following failure of surgery in patients with LA-ESCC. Camrelizumab is a PD-1 inhibitor that has been approved for use in combination with cisplatin and paclitaxel for the first-line treatment of patients with advanced ESCC in China.
The multicenter, open-label, randomized, phase 3 ESCORT-NEO/NCCES01 trial included patients aged 18 to 75 years who had histologically confirmed, resectable thoracic LA-ESCC (stages T1b-3N1-3M0 or T3N0M0). They were required to have an ECOG performance status of 0 or 1 and could not have received prior treatment.
Patients were randomized 1:1:1 to receive camrelizumab plus nab-paclitaxel and cisplatin every 3 weeks for 2 cycles, followed by surgery, and subsequent camrelizumab every 3 weeks for up to 15 cycles (group A); camrelizumab plus paclitaxel and cisplatin every 3 weeks for 2 cycles, followed by surgery, and subsequent camrelizumab every 3 weeks for up to 15 cycles (group B); or paclitaxel and cisplatin alone every 3 weeks for 2 cycles, followed by surgery, and subsequent surveillance (group C). Nab-paclitaxel was given intravenously (IV) at 125 mg/m2 on days 1 and 8 every 3 weeks, paclitaxel was given IV at 175 mg/m2 on day 1 every 3 weeks, and cisplatin was given IV at 75 mg/m2 on day 1 every 3 weeks. Camrelizumab was administered at 200 mg IV on day 1 every 3 weeks.
Patients were stratified by disease stage (stages I to II vs III vs IVA). The coprimary end points were pCR, assessed by a blinded independent review committee, and investigator-assessed event-free survival (EFS). Secondary end points comprised molecular pathologic response (MPR), R0 resection rate, ypTNM staging, disease-free survival, overall survival, and safety. Exploratory end points included biomarkers and patient-reported outcomes.
In group A, 129 patients completed 2 cycles of treatment; 18 did not undergo definitive surgery due to patient refusal (n = 14) or surgery intolerability (n = 4). In group B, 125 patients received 2 cycles of therapy; 14 patients did not undergo surgery due to patient refusal (n = 4), surgery intolerability (n = 3), preoperative death (n = 1), or other (n = 6). Finally, in group C, 122 patients completed 2 cycles of therapy; 22 patients did not undergo definitive surgery due to patient refusal (n = 12), lost to follow-up (n = 1), or other (n = 9).
Regarding baseline characteristics across the treatment arms, the median age was 63.7 years (range, 44-75), and 15.1% of patients were female. A total of 19.5% of patients had an ECOG performance status of 1 and more than half had a middle tumor location (51.4%). Most patients had T3 stage (86.4%), N1 stage (55%), and stage III disease (71.3%). Three-fourths of patients had less than 10% PD-L1 tumor proportion score (TPS; 75.2%), and 78.5% had a PD-L1 combined positive score (CPS) of 1 or greater (78.5%).
Additional data showed that the camrelizumab/nab-paclitaxel/cisplatin regimen improved pCR vs chemotherapy alone across all prespecified subgroups, including age, sex, clinical stage, PD-L1 TPS or CPS, ECOG performance status, and tumor location.
In the ITT population, the MPR rates were 59.1% (95% CI, 50.2%-67.6%) 36.2% (95% CI, 27.9%-45.0%), and 20.9% (95% CI, 14.3%-29.0%) in groups A, B, and C, respectively. This translated to a 38.3% difference (95% CI, 27.4%-49.3%) between arms A and C and a 15.4% difference (95% CI, 4.7%-26.2%) between arms B and C, with ORs of 5.51 (95% CI, 3.18-9.56) and 2.19 (95% CI, 1.25-3.84), respectively.
In group A, the tumor regression grade (TRG) was 1 for 41.2% of patients, 2 for 21.1% of patients, 3 for 26.3% of patients, 4 for 11.4% of patients, and 5 for 0% of patients; in group B, these respective rates were 19.8%, 18.1%, 31.0%, 29.3%, and 1.7%, respectively, and in group C, these rates were 6.8%, 11.7%, 31.1%, 45.6%, and 4.9%, respectively.
Li also provided a surgery summary of the 3 treatment arms. The definitive surgery rate was 86.4% in group A, 89.2% in group B, and 79.8% in group C. Most patients underwent the McKeown surgical procedure, as seen in group A (93.9%), group B (91.4%), and group C (92.2%). Additionally, most had total two-field as their lymph node dissection extent in 85.1%, 86.2%, and 79.6% of patients, respectively. The median duration of surgery was 4.3 hours (range, 2.6-8.9) in group A, 4.2 hours (range, 2.8-7.2) in group B, and 4.2 hours (range, 2.9-10.8) in group C. Most patients had a margin status of 0 (99.1%; 95.7%; 92.2%). One patient each in groups B and C underwent reoperations. In group A, 1 patient died within 30 days and 2 within 90 days; 2 patients each died within 30 and 90 days in group B; and 1 patient each died within 30 and 90 days in group C.
Any-grade and grade 3 or higher surgical complications occurred in 34.2% and 6.1% of patients in group A, respectively; these rates were 38.8% and 12.1% in group B and 32.0% and 6.8% in group C. In group A, the most common complications included pneumonia (any-grade, 10.5%), recurrent laryngeal nerve injury (any-grade, 9.6%), and dysrhythmia (any-grade, 6.1%). In group B, the most common complications were pneumonia (any-grade, 18.1%; grade ≥3, 0.9%), recurrent laryngeal nerve injury (any-grade, 9.5%; grade ≥3, 0.9%), and pleural effusion (any-grade, 10.3%; grade ≥3, 6.0%).
Grade 3 or higher preoperative treatment-emergent adverse effects (TEAEs) occurred in 34.8%, 31.5%, and 29.6% of patients in groups A, B, and C, respectively. TEAEs leading to discontinuation of camrelizumab occurred in 0.8% and 0.8% of those in groups A and B. Chemotherapy discontinuation due to TEAEs occurred in 3.0% of those in group A, 3.8% of those in group B, and 0.8% of those in group C. One TEAE led to death, and this occurred in group B.
Grade 3 or higher preoperative treatment-related adverse effects (TRAEs) occurred in 34.1%, 29.2%, and 28.8% of patients in groups A, B, and C, respectively. One patient in groups A and B had TRAEs that led to camrelizumab discontinuation; 4 patients in arm A, 5 in arm B, and 1 in arm C experienced TRAEs that led to chemotherapy discontinuation. One patient in arm B had a TRAE that led to death. Serious adverse effects (AEs) occurred in 7.6% of patients in group A, 9.2% of those in group B, and 5.6% of those in group C. Preoperative immune-related AEs occurred in 27.3% (grade ≥3, 4.5%) and 24.6% (grade ≥3, 3.8%) of patients in groups A and B, respectively.
Li concluded that the study continues to mature for EFS.
Editor’s Note: Dr Li did not cite any disclosures.
