Multicenter Phase Research Articles

Phase II study of neoadjuvant durvalumab and tremelimumab in combination with gemcitabine and cisplatin in patients with intrahepatic cholangiocarcinoma that is borderline resectable or resectable with high risk for recurrence.

TPS4198 Background: Finding effective and tolerable neoadjuvant treatment to downstage borderline resectable intrahepatic cholangiocarcinoma (ICC) could increase the rate of R0 resections and significantly improve patient outcomes. The combination of gemcitabine, cisplatin, and durvalumab based on the TOPAZ-1 trial is now the preferred first-line regimen for advanced, unresectable biliary tract cancer (1). The objective response rate (ORR) was 26.7% for the 3-drug regimen. Gemcitabine, cisplatin, durvalumab, and tremelimumab (an anti-CTLA4 antibody) in advanced, unresectable biliary tract cancer had an objective response rate of 70% in a phase II study (2). Given this response to immunotherapy plus chemotherapy, the 4-drug combination of gemcitabine, cisplatin, durvalumab, plus tremelimumab in the neoadjuvant setting may be able to improve the conversion rate of borderline resectable ICC to resectable ICC and improve R0 resection rates. Methods: This is an open-label, single-arm, multicenter phase II safety and feasibility study of neoadjuvant gemcitabine + cisplatin + durvalumab + tremelimumab in patients with ICC that is borderline resectable or resectable with a high risk of recurrence. 24 patients will receive 3-week cycles of durvalumab 1500 mg on D1, tremelimumab 300 mg only on C1D1, gemcitabine 1000mg/m2 on D1 and D8, and cisplatin 25mg/m2 on D1 and D8. Treatment will be stopped after C4 if a patient is able to proceed with surgery, otherwise they will complete 8 cycles and be re-evaluated for surgery at that point. Key eligibility criteria include no prior systemic therapy, histologically proved ICC, ECOG 0-1, and disease that is not readily suitable for resection with curative intent based on discussion with multidisciplinary committee including a hepatobiliary surgeon. Primary endpoints are feasibility and safety with secondary endpoints of overall survival, progression free survival, ORR, R0 resection rate, and pathologic complete response. Molecular biomarkers from blood to predict outcomes and organoid development from circulating tumor cells are exploratory endpoints. The study will be carried out in 2 stages. In stage 1, 11 patients will be accrued and the study will be stopped if 2 or fewer patients undergo resection based on a null hypothesis of a resection rate after neoadjuvant treatment of about 24%. Otherwise, 17 more patients will be accrued in stage 2 (assuming 15% dropout rate to hit target of 24) and if 9 or more of the 24 patients undergo resection, we will claim the treatment is feasible. The design has a type 1 error rate of 0.1 and power 0.8. Patient follow-up will be up to 3 years. The study is currently enrolling participants. 1. Oh et al. NEJM Evid 2022. 2. Oh et al. Lancet Gastroenterol Hepatol 2022. Clinical trial information: NCT06017297 .

A phase II trial to evaluate the epithelial-to-mesenchymal (EMT) inhibitor sotevtamab combined with docetaxel in patients with metastatic non-small cell lung cancer following failure of primary chemoimmunotherapy.

8577 Background: Sotevtamab is an investigational humanized monoclonal antibody that binds to tumor associated secreted clusterin (TA-sCLU). TA-sCLU is a potent inducer of the epithelial-to-mesenchymal transition (EMT), a process known to contribute to tumor invasion, metastasis, chemoresistance and immune evasion. Sotevtamab abrogates the EMT-promoting activity of TA-sCLU by inhibiting its ability to be internalized in cancer cells. Methods: An open-label, single-arm, multi-center Phase II clinical study of sotevtamab administered in combination with docetaxel was performed in subjects with metastatic non-small cell lung cancer who had experienced progression following frontline immunochemotherapy. 35 subjects were enrolled from March 2021 to November 2022 and the study was completed in December 2023. Sotevtamab was administered at a dose of 12 mg/kg once weekly on Days 1, 8 and 15 combined with docetaxel at a dose of 75 mg/m2 once every 3 weeks on Day 1. One cycle of treatment consisted of 21 days. The primary objectives were to determine the objective response rate (ORR) and the safety and tolerability of the combination. Tumor biopsies were performed prior to study initiation and after two cycles of therapy for pharmacodynamicevaluation. Results: As per interim data obtained from a rolling database lock performed in February 2023, the mean subject age was 63 and 22 patients (63%) were female. Of the 35 subjects, 28 were diagnosed with adenocarcinoma, 6 with squamous cell carcinoma and 1 with adenosquamous carcinoma; 11 were ECOG 0, 22 ECOG 1 and 2 ECOG 2. Six subjects with adenocarcinoma had a partial response for an ORR of 17.1%. Stable disease (SD) was experienced in an additional 10 subjects (9 adenocarcinomas and one squamous cell carcinoma) for an SD rate of 28.6%. The observed responses were sustained with a median duration of over one year (405 days). The estimated one-year survival rate was 33.9%. The most frequent adverse events were fatigue, infusion related reaction (IRR), diarrhea, nausea and anemia. The incidence of IRR was significantly decreased following the implementation of a premedication protocol. Analysis of paired tumour biopsies revealed in certain patients that sotevtamab induced a strong intratumoral immune response with the formation of Tertiary Lymphoid Structures (TLS). Various pharmacodynamic evaluations are being performed to better define the profile of responding patients. Conclusions: This phase II study showed promising response and overall tumor control. Duration of response was particularly encouraging and relevant to further exploration. The sotevtamab and docetaxel combination may enhance immune-mediated anti-tumor response through induction of TLS. Data from the final database lock will be presented. Clinical trial information: NCT04364620 .

The safety and efficacy of ivonescimab in combination with chemotherapy as first-line treatment for advanced biliary tract cancer.

4095 Background: Despite that PD-1/L1 inhibitors combined with chemotherapy have been approved as first-line(1L) treatment for advanced biliary tract cancer (BTC), the overall survival benefit remains limited, particularly for patients with gallbladder cancer. Ivonescimab, a tetrameric bispecific antibody targeting PD-1 and VEGF, has the potential to produce complementary and synergistic anti-tumor effects through both pathways. This study aimed to evaluate the safety and efficacy of ivonescimab in combination with chemotherapy in advanced BTC. Methods: This was an open-label, multi-center phase II study in patients with unresectable locally advanced and metastatic BTC. Ivonescimab was administered every 3 weeks for up to 8 cycles, along with gemcitabine and cis-platinum. After that, ivonescimab monotherapy was given until disease progression or unacceptable toxicity. The primary endpoints were safety and objective response rate (ORR) by RECIST v1.1. Secondary endpoints included duration of response (DoR), disease control rate (DCR), time-to-response (TTR), progression-free survival (PFS), and overall survival (OS). Results: As of Nov 26, 2023, a total of 22 pts with advanced BTC were enrolled in the study. The median age was 65.0 years (range, 47-75), 81.8% of patients had ECOG of 1. All patients had initially unresectable disease status, 54.5% of patients had intrahepatic cholangiocarcinoma, 4.5% of patients had extrahepatic cholangiocarcinoma and 40.9% of patients had gallbladder cancer at baseline. The median follow-up time was 10.7 months, and the median exposure time of ivonescimab was 7.2 months. A total of 86.4% (19/22) of patients experienced at least one grade 3 or higher treatment-related adverse event (TRAE), but none led to discontinuation treatment or death. The most common grade 3/4 TRAEs with a frequency of at least 10% included white blood cell count decreased (50.0%), neutrophil count decreased (50.0%), anemia (40.9%), platelet count decreased (22.7%), and hypertension (13.6%). The ORR by investigator assessment was 63.6% (14/22) regardless of PD-L1 status, with an ORR of 77.8% (7/9) for gallbladder cancer patients specifically. The DCR was 100% (22/22). The median PFS was 8.5 months (95% CI, 6.8-9.9), with a 6-month PFS rate of 84.2% (95% CI, 58.7-94.6). The median OS was 16.8 months (95% CI, 9.8- NE), with a 9-month OS rate of 81.8% (95% CI, 58.5-92.8). Conclusions: Ivonescimab combined with chemotherapy as 1L treatment demonstrated promising efficacy in pts with advanced BTC. Further trials to validate the efficacy and safety are warranted. Clinical trial information: NCT05214482 .

Efficacy, safety and DNA methylation analysis of cadonilimab combined with taxane and cisplatin as the first-line treatment in patients with advanced esophageal squamous cell carcinoma (ESCC): An open-label, multicenter phase II trial– Updated results from AK104-IIT-014.

e16064 Background: Immune checkpoint inhibitors combined with chemotherapy has become the current first-line standard treatment for advanced ESCC, while still having a lot of room for improvements in objective responses and survival. Cadonilimab, a bispecific antibody simultaneously targeting PD-1 and CTLA-4, may further boost anti-tumour activity with a satisfied safety profile. Here, we present the updated data for the safety and efficacy of Cadonilimab combination therapy as the first-line treatment in advanced ESCC. Methods: Treatment-naïve patients (pts) with unresectable locally advanced or metastatic ESCC were eligible for inclusion. Cadonilimab (10mg/kg, iv, d1, q3w) combined with paclitaxel or nab-paclitaxel (175 mg/m2, iv, d1, q3w) and cisplatin (65 to 75 mg/m2, iv, d1, q3w) were administrated for up to 6 cycles, then Cadonilimab (10mg/kg, iv, d1, q3w) monotherapy continued as maintenance until progressive disease or unacceptable toxicity, with a maximum of 24 months. The primary endpoint was objective response rate (ORR). Secondary endpoints were progression-free survival (PFS), overall survival (OS), disease control rate (DCR) and safety. Plasma cell-free DNA samples were collected before and after treatment and prepared for DNA methylation level sequencing. Results: At updated analysis (cut-off: February 5, 2024), 35 pts were enrolled with a median age of 61 years (range 44-75), 82.9% were male, 57.1% had PD-L1 CPS<10 and 88.6% had distant metastases. In the efficacy-evaluable population (n = 29), 5 pts reached complete response (CR), 21 pts had partial response (PR) and 3 pts had stable disease (SD). The ORR was 89.7% (95%Cl: 71.5%-97.3%) and the DCR was 100.0% (95%Cl: 85.4%-100.0%). Among evaluable pts with PD-L1 CPS≥10 and PD-L1 CPS<10, the ORR were 100.0% (12/12) and 81.3% (13/16), respectively. SEPT9 methylation was significantly higher in patients with CR or PR compared to patients with SD (33.28% vs 3.87%, p < 0.001). The median PFS and OS was still not reached. Grade 3 or higher treatment-related adverse events (TRAEs) occurred in 9 (25.7%) pts. The most common TRAEs were neutropenia (17.1%), leukopenia (5.7%) and hyponatremia (5.7%). Immune-related adverse events were observed in 9 pts (25.7%). Three pts (8.6%) suffered from serious adverse events, and no grade 5 TRAEs or death were observed. Conclusions: The updated results suggested that bispecific antibody AK104 combined with taxane and cisplatin as first-line treatment showed promising anti-tumor activity and manageable safety in patients with advanced ESCC. DNA methylation level might be a potential biomarker for guiding patient outcomes. Follow-up is ongoing for survival analysis. Clinical trial information: NCT05522894 .

Updated results from ALTER-S002: A single-arm multicenter trial of the combination of anlotinib with chemotherapy in patients with stage IIB classic osteosarcoma of the extremity.

11529 Background: The overexpression of multiple tyrosine kinase receptors in osteosarcoma indicated a promising therapy targeting these receptors. Anlotinib is a multi-targeted tyrosine kinase inhibitor that potentially inhibits tumor angiogenesis. The combination of anti-angiogenic drugs with chemotherapeutic agents is proposed to act synergistically to achieve favorable tumor control, especially as the neoadjuvant therapy. We had reported the neoadjuvant therapy data of anlotinib in combination with chemotherapy for treatment-naive stage IIB classical osteosarcoma of the extremity in the 2023 ESMO congress. Here we report an update on the effectiveness and safety of the follow-up. Methods: In this open-label, single-arm, multicenter phase II clinical trial. Eligible patients(pts) were aged 12-40 years with histologically confirmed primary localized extremity classic osteosarcoma, stage IIB, operable. Pts received anlotinib (10mg, po, d1-14, q3w), doxorubicin (A) (20-25mg/m2 iv, d1-3, q3w) and cisplatin (P) (70-90mg/m2, iv, d1, q3w) for the first nine weeks. Pts underwent radical surgery after the exclusion of contraindications at week 10. After surgery, pts received A+P at weeks 12-14, and anlotinib plus A+P at weeks 15-20 with the drug dose unchanged. Since week 21, anlotinib (12mg, po, d1-14, q3w) monotherapy was maintained until week 104 or the occurrence of an EFS event. The primary endpoint was 24-month EFS rate, secondary endpoints were 36-month EFS rate, local recurrence rate, lung metastasis rate, 3-year OS rate and safety. Results: From May 2020 to Apr 2022, 52 eligible pts were enrolled, while 51 pts underwent surgery after 3 cycles of neoadjuvant therapy. At the data cut-off date (Oct. 2023), the median EFS was not reached, 12 and 24-month EFS rates were 84.18% (95% CI :70.82, 91.77) and 73.43% (95% CI :57.40, 84.21), respectively. The stratified analysis of EFS showed that the length and diameter of the target lesion are independent prognostic factors. The median OS was not reached, the 24-month OS rate was 95.92% (95% CI :84.65, 98.96). Among the 51 pts who underwent surgical treatment, 12(23.53%, 95% CI: 12.79, 37.49) pts experienced recurrence or metastasis. Most treatment-related adverse events (TRAEs) were grade 1-2. Grade 3/4 TRAEs (≥20%) included neutropenia (51.92%), leukopenia (38.46%), thrombocytopenia (36.54%) and anemia (32.69%). Conclusions: The updated results suggested that anlotinib combined with doxorubicin and cisplatin in the perioperative period showed favorable efficiency and manageable adverse events in Stage IIB classic osteosarcoma of the extremity. Clinical trial information: ChiCTR 2000033298.

Efficacy and safety of recombinant human adenovirus type 5 (H101) combined with immune checkpoint inhibitors (ICIs) in patients with liver metastatic gastric cancer: A prospective multicenter phase II study (the TROJAN 021 study).

2635 Background: Immune checkpoint inhibitors (ICIs) have shown significant efficacy in metastatic gastric cancer, but some patients may not respond to them because of immune resistance. Recombinant Human Adenovirus Type 5 (H101), the world’s first oncolytic virus antitumor drug in China, can induce cell death, expose tumor antigens, provide adjuvants for anti-tumor immune priming, and potentially increase responsiveness to immunotherapies. Here, we presented the efficacy and safety of H101 combined with immune checkpoint inhibitors (ICIs) in patients with liver metastatic gastric cancer. Methods: In this multi-center, phase II trial (the TROJAN 021 study, ChiCTR1900027922), patients with liver metastatic gastric cancer received 2 cycles of H101 ultrasound guided injections into liver lesions, bi-weekly in combination with anti-PD-1 antibodies and chemotherapy bi-weekly until progression or intolerable toxicity. The primary objective was safety and objective response rate (ORR). Secondary objective included progression-free survival (PFS), overall survival (OS) and disease control rate (DCR). Efficacy assessments were performed every 4 weeks following RECIST v1.1 criteria. PFS and OS were estimated using the Kaplan-Meier method. Results: From September 2020 to September 2022, 21 patients were enrolled. Of them, 18 were males, median age was 66 years (range: 36-71) and ECOG performance status was either 0 (n=15) or 1 (n=6). 10 patients (47.6%) received as first-line therapy, 1 (4.8%) as second-line and 5 (23.8%) as third line and above therapy. The primary endpoint was met with a median PFS of 4.8 months. The median OS was 13.2 months. Objective tumor responses were CR (n=0), PR (n=7), SD (n=12) and PD (n=2). ORR was 33.3% (7/21), and DCR was 90.5% (19/21). Treatment related adverse events (TRAE) occurred in 12 patients (57.1%). The most frequently observed TRAEs were injection site pain (48.1%), fever (57.1%) and fatigue (23.8%). Three patients (14.3%) had grade 3 treatment-related adverse events. There were no grade 4 and 5 treatment-related adverse events. Grades 3 toxicities included neutropenia (2/21, 9.5%) and hypertension (1/21, 4.8%). Conclusions: These promising results show that combination of Recombinant Human Adenovirus Type 5 (H101) and ICIs demonstrated acceptable toxicity and promising antitumor efficacy in patients with liver metastatic gastric cancer. Further validation of the efficacy in a randomized prospective trial is warranted. Clinical trial information: ChiCTR1900027922.

Treatment of acute myeloid leukemia with Orca-T.

6552 Background: Allogeneic hematopoietic stem cell transplants (alloHSCT) offer a potential curative treatment for many hematological cancers, however, traditional alloHSCT is associated with high mortality from complications including infection, graft versus host disease (GvHD) and relapse. Orca-T is an investigational allogeneic T-cell immunotherapy that includes stem and immune cells, derived from allogeneic donors, that leverages highly purified, polyclonal donor regulatory T cells to control alloreactive immune responses. In this sub-group analysis, we evaluated the safety and efficacy of patients with acute myeloid leukemia who were treated with Orca-T. Methods: Data from 37 patients with the diagnosis of acute myeloid leukemia (AML) in CR/CRi who received myeloablative conditioning with busulfan, fludarabine, and thiotepa (BFT) followed by Orca-T by 6/30/22 as part of a multicenter phase 1b single-arm trial (NCT04013685) are reported here. Patients enrolled in the phase 1b trial who did not meet these criteria were not included in this analysis. Patients received BFT prior to Orca-T, followed by single-agent GvHD prophylaxis with tacrolimus, and had an 8/8 related or unrelated matched donor. Donors were matched via DNA-based high-resolution typing of HLA-A, -B, -C, and -DRB1. Results: Orca-T was successfully manufactured at a centralized GMP facility, distributed, and infused at study sites throughout the U.S. Vein-to-vein time (i.e. time between end of donor apheresis to start of recipient’s Orca-T infusion) was < 72 hours for all patients, with the majority < 60 hours. Median age was 51 years, 49% were female and 16% were of Hispanic or Latino ethnicity. Twenty-three (62%) had matched related donors and 14 (38%) had matched unrelated donors. Baseline HCT-CI score was 3 and 4 in 27% and 8% of the patients, respectively. The majority had intermediate DRI scores (89%) and 41% were MRD positive at baseline. The median duration of follow-up was 14 months. Relapse-free survival at 12 months was 81.4% (95% CI: 62.9, 91.2). Non-relapse mortality and overall survival were 0% and 100% at 12 months, respectively. Conclusions: These encouraging results suggest that investigational Orca-T could represent a reduced toxicity alternative to conventional alloHSCT. This combination of Orca-T with myeloablative BFT led to > 80% RFS without treatment related mortality, and 100% overall survival in this AML patient population. These outcomes were accomplished with consistent and reliable cell manufacturing and distribution of Orca-T at a national scale. A multi-center randomized controlled phase 3 trial comparing Orca-T to SOC, utilizing BFT or TBI-based conditioning, will complete enrollment during the first half of 2024. (NCT05316701). Clinical trial information: NCT04013685 .

Anlotinib combined with penpulimab as first-line treatment for persistent, recurrent, or metastatic cervical cancer: Preliminary results from ALTER-GO-020, a single-arm, open-label, multi-cohort, multi-center phase II clinical study.

e17506 Background: The BEATcc trial demonstrated the combination of atezolizumab plus bevacizumab and platinum regimen as first-line treatment for recurrent, or metastatic cervical cancer significantly improves progression-free survival (PFS) and overall survival (OS) regardless of PD-L1 status. ALTER-GO-020 is an ongoing open-label, single-arm, multi-cohort phase II study evaluating the combination of anlotinib (a multitarget anti-angiogenic TKI) and penpulimab (anti-PD-1 antibody) as a chemotherapy-free regimen for patients (pts) with recurrent or metastatic gynecological cancer. Here, we report the preliminary results of the cohort of patients with recurrent or metastatic cervical cancer from ALTER-GO-020. Methods: Eligible pts were histologically confirmed persistent, recurrent, or metastatic cervical cancer (including adenocarcinoma, adenosquamous carcinoma, or squamous-cell carcinoma), not amenable to curative treatment, and had no prior systemic treatment for metastatic, persistent, or recurrent disease. Pts were treated with anlotinib (12mg, po qd, d1-14, q3w) plus penpulimab (200mg, IV, d1, q3w) until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) and the secondary endpoints included PFS, duration of response (DOR), disease control rate (DCR), OS and safety. Results: From May 2022 to Nov 2023, 17 pts were enrolled. The median age was 52 years (range, 31-70), 65% of pts were squamous-cell carcinoma, 88% received previous chemoradiotherapy with or without surgery, and 71% had previously received neoadjuvant/adjuvant platinum-containing chemotherapy. As of date cutoff (Dec, 2023), the median follow-up time was 6.8 months (range, 1.4-18.3 months). In the efficacy analysis (n=17), the preliminary ORR was 58.8% (95% CI: 32.9%-81.6%), DCR was 88.2% (95% CI: 63.6%-98.5%). The mPFS was 11.0 months (95% CI: 5.4-16.7 months). The mOS was not reached. Treatment-related adverse events (TRAEs) of any grade occurred in all 17 pts, in which 8 (47.1%) were grade ≥3. The most common grade ≥3 TRAEs were hypertension (29.4%), hand foot syndrome (11.8%), fatigue (11.8%), and diarrhea (5.9%). TRAEs led to dose reduction and interruption were 29.4%, and 35.3% of pts, respectively. No TRAEs leading to death. Conclusions: The preliminary results demonstrated that anlotinib plus penpulimab as a first-line therapy for persistent, recurrent, or metastatic cervical cancer showed promising antitumor efficacy and manageable safety profile. Clinical trial information: NCT05028504 .

Safety and efficacy of eribulin plus anlotinib in patients with advanced soft tissue sarcoma (ERAS): A multi-center phase II study.

11561 Background: Both the microtubule-dynamics inhibitor eribulin and the multi-targeted tyrosine kinase inhibitor anlotinib exhibit single-agent anti-tumor activity in previously treated soft tissue sarcoma (STS). This study aimed to evaluate the efficacy and safety of the combination treatment of eribulin and anlotinib in patients with advanced STS. Methods: In this multi-center phase II study (ERAS), patients with advanced soft tissue sarcoma who relapsed/progressed after anthracycline chemotherapy or were not candidates for such treatment were included. Patients received eribulin (1.1 mg/m² intravenously on days 1 and 8) and anlotinib (12mg orally once daily on days 1-14) every 21 days for 6-8 cycles, followed by anlotinib maintenance. The primary endpoint was progression-free survival rate at 24 weeks (PFR24w). Secondary endpoints included median progression-free survival (mPFS), median overall survival (mOS), objective response rate (ORR), disease control rate (DCR) and safety. Results: Thirty-one patients were enrolled. Twenty-eight (90.3%) patients had received anthracycline chemotherapy, and the remaining 3 (9.7%) were chemotherapy-naïve. Pathological types included L-type sarcomas (10 leiomyosarcomas and 6 dedifferentiated liposarcomas) and non-L-type sarcomas (n =15, with 8 subtypes). As of the cut-off date of Jan 28, 2024, the median follow-up time was 30.4 weeks. Response evaluation was feasible in 29 patients. The ORR, DCR and predicted PFR24w were 20.7%, 82.8% and 65.5%, respectively. The mPFS was 30.1 weeks, with no significant difference observed between patients with L-type sarcomas and non-L-type sarcomas. The mOS was not reached. Nineteen (61.3%) patients experienced at least one grade 3/4 adverse event. The most common grade 3/4 adverse events included neutropenia (35.5%), leukopenia (25.8%), hypertension (16.1%), hypertriglyceridemia (16.1%) and increased gamma-glutamyl transpeptidase (16.1%). Conclusions: The combination of eribulin and anlotinib shows promising efficacy with an acceptable toxicity profile in patients with advanced STS, irrespective of pathological type. Clinical trial information: ChiCTR2300067650.

Preliminary results of a randomized controlled, open-label, multi-center phase II study of camrelizumab combined with chemotherapy followed by concurrent chemoradiotherapy and camrelizumab consolidation therapy versus standard chemoradiotherapy as first-line treatment for limited-disease small cell lung cancer.

e20132 Background: Immune checkpoint inhibitors combined with chemotherapy have significant clinical benefits in extensive-stage small cell lung cancer (SCLC). However, for patients with limited-disease SCLC (LD-SCLC), the data on immunotherapy combined with chemoradiotherapy is insufficient. Methods: In this open-label, multi-center, phase 2 trial, we randomly 1:1 assigned patients with previously untreated LD-SCLC to receive camrelizumab combined with chemotherapy followed by concurrent chemoradiotherapy (CCRT) and camrelizumab consolidation therapy or standard chemoradiotherapy. Patients with ECOG performance status of 0 to 1, and adequate organ function were eligible. For thoracic radiation, 45 Gy in 3 weeks (1.5 Gy, BID) was given on the first day of the third cycle of chemotherapy. An etoposide plus platinum-based regimen was given 4 cycles in total. Patients who had a good response to initial treatment were offered prophylactic cranial irradiation. The primary endpoint was the 1-year progression-free survival rate. We assumed that the 1-year PFS rate in the experimental group was expected to reach 65% compared to chemoradiotherapy alone group 45%, and planned to enroll 112 patients with 56 in each group. Results: Up to date, we have enrolled 40 patients. The median follow-up was 10.6 months. Safety was evaluated in all treated patients. No Grade 5 adverse event was observed. Grade 3 or 4 treatment-related adverse events occurred in 58.8% of the patients in the camrelizumab plus chemoradiotherapy and in 52.9% of those in the chemoradiotherapy alone group. The most frequent grade 3 or 4 adverse events were hematologic toxicities (70.6% vs. 58.8%). Acute esophagitis and pneumonitis of grade 3 occurred in both groups were 1/17 (5.9%) and 1/17 (5.9%), respectively. In the experimental group, only one patient was developed grade 3 immune pneumonia 1/17 (5.9%). The 1-year PFS rate was 54.5% (95% confidence interval [CI] 19.5%-89.6%) with camrelizumab plus chemoradiotherapy and 44.4% (95% CI 3.9%-88.0%) with chemoradiotherapy alone. Among the 17 patients who received camrelizumab, the median PFS time was not reached, as compared with 14.35 (95% CI, 8.15-20.91) months among the 17 patients with chemoradiotherapy alone. Conclusions: In patients with LD-SCLC, the addition of camrelizumab to chemoradiotherapy did not increase the incidence of adverse events. Camrelizumab plus chemoradiotherapy resulted in an encouraging 1-year PFS rate. Larger sample sizes and longer follow-up times are required to validate our preliminary results. Clinical trial information: ChiCTR2000032275.

METAPANC, intensified treatment in patients with oligometastatic pancreatic cancer: Multimodal surgical treatment versus systemic chemotherapy alone—A prospective randomized controlled multicenter phase III trial.

TPS4207 Background: Pancreatic ductal adenocarcinoma (PDAC) has a dismal overall survival rate due to early metastasis and high therapy resistance. The successful introduction of intensified chemotherapeutic regimen such as FOLFIRINOX (FFX) has significantly increased response rates, disease control and overall survival. Current standards recommend systemic chemotherapy but no surgical approach in metastatic PDAC. FFX has the highest rates of response and overall survival and is a current standard of care in patients with metastatic PDAC and good performance status. Extensive surgical interventions with synchronous or metachronous metastasectomy is not recommended according to current guidelines. Retrospective data suggest beneficial outcomes in patients with hepatic oligometastasis, though prospective data from randomized clinical trials are not available. Methods: METAPANC is a prospective randomized controlled multicenter phase III trial evaluating survival and quality of life after multimodal therapy with perioperative modified FOLFIRINOX (mFFX) chemotherapy (two times 4 cycles prior to resection of the primary tumor and resection of the metastases), followed by 4 cycles of adjuvant mFFX chemotherapy (Arm A) vs. mFFX (without surgery), as standard of care first-line treatment (Arm B). Patients are eligible for randomization after 8 cycles of mFFX if they have at least stable disease on imaging according to RECIST V1.1 (Response Assessment I after 4 cycles and Response Assessment II after 8 cycles of mFFX). Patients with progressive disease will be excluded from the study. This clinical trial will focus on a well-defined patient collective with resectable PDAC and metastatic load limited to the liver with a maximum of three metastases. Patients with metachronous liver metastatic status can also be included, but must have completed adjuvant chemotherapy at least 6 months before start of study treatment. In patients randomized into Arm A with metastatic lesions located in the center of the liver local ablative techniques can be combined. In total 272 patients will be enrolled and will be randomized 1:1. The primary endpoint is overall survival, secondary endpoints are progression free survival, procedure related complications and mortality, quality of life, quality-adjusted time without symptoms and toxicity. METAPANC is accompanied by an exploratory biomarker analysis program of collecting biological and imaging samples to subsequently identify and evaluate molecular-based patient subgroups and biomarkers for identification of a potential target population which may benefit from the intensified multimodal treatment strategy. 22 German participating sites are selected. Further international sites are planned in the Netherlands, Norway, Finland and Sweden. Clinical trial information: 2023-503558-10-00.

A phase IV study of ApricityCARE program for cancer adverse events rapid evaluation to improve treatment outcomes of ethnic/racial minority patients with non-small cell lung cancer (NSCLC) receiving immune checkpoint inhibitors (ICI).

TPS1642 Background: ICI have changed the treatment landscape of NSCLC, with many now FDA approved in not just advanced, but even early-stage disease. With the increase in ICI use, the incidence of immune-related adverse effects (irAEs) has also risen, occurring in up to 16% of ICI-treated patients. Prompt recognition and timely management are necessary to avert potential poor outcomes from direct toxicity and/or early treatment discontinuation. However, existing barriers to access care that disproportionately impact racial and ethnic minority patients may amplify challenges in early, effective management of irAEs. Using technology-enabled health interventions in a culturally competent manner can improve access to health care resources and reduce health disparities. These platforms need to be optimized at the technology and health literacy level of underserved minority communities and adapted to meet the community's needs. Methods: We have designed a multi-center phase IV clinical trial to 1) assess factors related to suboptimal and optimal use of the ApricityCARE, a virtual first-response clinical support (or coverage) to provide 24/7 symptom monitoring and side effect management and 2) determine the impact of the program on ICI toxicity management for NSCLC patients receiving ICIs in a highly diverse community. Eligible patients are those with a confirmed diagnosis of NSCLC who self-identify as a member of an ethnic minority or underserved population, prescribed for any treatment regimen that includes an ICI. The study entails a 50-patient run-in phase with two focus group discussions, stratified on a Likert-type scale based on the frequency of utilization, to determine factors impacting usability of the ApricityCare program. This data will inform optimal implementation of ApricityCare for the randomized phase of the study, where 230 patients will be assigned 1:1 to use of ApricityCare versus standard of care. The run-in phase of the study is currently accruing at Columbia University, and is planned to open at NYU, Mount Sinai, and Montefiore (NCT05812274). Clinical trial information: NCT05812274 .

Preliminary efficacy and safety results from RC48-C017: A phase II study of neoadjuvant treatment with disitamab vedotin plus toripalimab in patients with muscle invasive bladder cancer (MIBC) with HER2 expression.

4568 Background: Disitamab vedotin (DV) is a novel humanized anti-HER2 antibody-drug conjugate. DV plus toripalimab (a recombinant humanized anti-PD-1 monoclonal antibody) showed promising antitumor activity in metastatic urothelial carcinoma (ASCO 2023). This study aimed to evaluate the safety and efficacy of DV plus toripalimab as neoadjuvant therapy in MIBC patients with HER2 expression. Methods: This is a prospective multicenter phase 2 trial which planned to enroll 40 pts. Primary endpoint is pathological CR (pCR) rate; secondary endpoints include pathologic response rate, safety and tolerability. Study enrolled pts who are previously untreated MIBC (cT2-T4aN0-1M0), medically fit for and agree to undergo curative intent RC+PLND. HER2 expression was required to be immunochemistry (IHC) ≥ 1+ tested locally. Pts received DV 2 mg/kg plus toripalimab 3 mg/kg every two weeks for 6 cycles, followed by RC+ PLND within 4 weeks. Here we present preliminary efficacy and safety results. Results: 44 pts were enrolled and clinical stage at diagnosis was: cT2N0 (38.6%), cT3N0 (29.5%), cT4aN0 (13.6%), cT2-4aN1 (18.2%). HER2 expression of IHC 1+, 2+ or 3+ was 11.4%, 56.8%, and 31.8%, respectively. By the data cut-off date (Feb-2024), 29 pts (65.9%) completed RC + PLND. The pCR rate was 62.1% (18/29). The pathologic response rate was 75.9% (22/29). Common treatment-related adverse events (TRAEs) were mostly Grade 1 or 2, including alopecia (36.4%), alanine aminotransferase increased (31.8%), aspartate aminotransferase increased (25.0%), rash (22.7%), gamma-glutamyl transferase increased (22.7%), peripheral sensory neuropathy (22.7%), and asthenia (20.5%). Grade 3-4 TRAEs were reported in 15.9% of pts. No deaths occurred. No surgery was cancelled due to TRAEs. Survival data are not yet mature. Conclusions: Neoadjuvant treatment with DV plus toripalimab showed promising efficacy results and was well tolerated in operable MIBC pts with HER2 expression. These results will support further investigation for DV plus toripalimab in this population. Clinical trial information: NCT05297552 .

Intra-treatment hypoxia directed major radiation de-escalation as definitive treatment for human papillomavirus-related oropharyngeal cancer.

6007 Background: We previously reported that surgery to the primary site with hypoxia-directed de-escalated radiation to the neck for human papillomavirus associated oropharyngeal carcinoma (HPV+ OPC) can lead to excellent oncologic outcomes. We now report the results of a successor multi-center phase II trial of hypoxia-directed de-escalated chemoradiotherapy without surgery for HPV+OPC. Methods: HPV+ OPC (T0-2/N1-N2c/AJCC 7th) patients were eligible for enrollment. Tumors without evidence of hypoxia on 18F-FMISO (fluoromisonidazole) PET received de-escalated chemoradiation to 30Gy while those with hypoxia received chemoradiation to 70Gy. The primary objective was achieving a 2-year locoregional control (LRC) of 95% (failure was locoregional recurrence where surgical salvage was unfeasible) with a 7% non-inferiority margin. We enrolled a total of 158 subjects upfront to account for a 5% loss due to death (of reasons other than cancer) or follow-up. Secondary objectives were local failure (LF), regional failure (RF), distant metastasis (DM), overall survival (OS), toxicities, and patient-reported MD Anderson Dysphagia Inventory (MDADI) scores. LF, RF, and DM were estimated using the Cumulative Incidence Function, and OS was estimated using the Kaplan-Meier method. Results were reported up to 1/31/2024. Results: From 4/28/20-4/17/23, 158 HPV+ OPC patients were enrolled where150 patients were eligible for analyses. Patient characteristics: Tonsil (43%); Base of Tongue (47%); unknown primary (10%); >/=10 pack years (22%); T0 (9%), T1 (44%), T2 (47%); N1 (14%), N2a (11%), N2b (59%), N2c (16%). 111 (74%) received 30Gy; 95% cisplatin. With 24 months (8-43) of median follow-up, the 2-year LF, RF, DM rates were 4.2%, 6.9%, 2.0%, respectively. The 2-year overall survival probability was 99%. Only 2 patients could not undergo salvage surgery [one 30Gy (second recurrence); one 70Gy (M1)], both received systemic therapy with durable response. Acute grade 3-4 toxicities were 32% (67% neutropenia). Mean MDADI scores: 92.93 (baseline); 68.24 (3 weeks), 91.45 (4 months) after chemoradiation. Conclusions: These early data indicate that major de-escalation to 30Gy based on hypoxia status achieved significant toxicity reduction without compromise in survival for HPV+ OPC treated with chemoradiation without surgery. Clinical trial information: NCT03323463 .

Adjuvant chemotherapy with mFOLFOXIRI versus mFOLFOX6 in MRD-positive stage II-III colorectal cancer.

TPS3642 Background: About 25% to 30% of resectable high-risk stage II and stage III colon cancers might relapse after radical resection and adjuvant chemotherapy with FOLFOX regimen. Recent studies have underscored the significance of circulating tumor DNA (ctDNA)-based minimal residual disease (MRD), representing a residual presence of cancer cells, as a prognostic factor for postoperative recurrence in CRC. Patients exhibiting positive MRD predicted a considerable high risk of recurrence and metastasis, even after adjuvant chemotherapy. In the realm of postoperative adjuvant chemotherapy, Comparing with FOLFOX, whether the early introduction of intensified chemotherapy, mFOLFOXIRI, could further eradicate MRD and improve the long-term prognosis remains unclear. Methods: This multicenter phase III study (NCT05427669) plans to enroll 340 colorectal cancer patients with MRD positive after curative-intent R0 surgical resection, age 18 to 70 years, ECOG performance status 0-1. Patients were randomized (1:1) to receive mFOLFOXIRI (oxaliplatin 85 mg/m², leucovorin 400 mg/m², irinotecan 150 mg/m², and 5-FU 2.4 g/m²over 46 h) or mFOLFOX6 (oxaliplatin 85 mg/m², leucovorin 400 mg/m², 5-FU bolus 400 mg/m2 then 2.4 g/m² over 46 h) every two weeks for 24 weeks (12 cycles). Patients will be followed for 5 years after the end of adjuvant chemotherapy. The primary endpoint was 3-year DFS. A gain of 14% in 3-yr DFS is expected (74% in the experimental arm vs. 60% in the control arm; α, 5% [two-sided log-rank test]; 1-β, 80%). Secondary endpoints included overall survival, 3-year distant metastasis-free survival, QoL and toxicity. Clinical trial information: NCT05427669 .

Results from METIS (EF-25), an international, multicenter phase III randomized study evaluating the efficacy and safety of tumor treating fields (TTFields) therapy in NSCLC patients with brain metastases.

2008 Background: For non-small cell lung cancer (NSCLC) with brain metastases (BM) stereotactic radiosurgery (SRS) is the current preferred therapy. Due to frequent intracranial failures, there is a high unmet need for salvage therapies. Whole brain radiotherapy (WBRT) reduces intracranial failure but used less frequently due to cognitive consequences. Tumor Treating Fields (TTFields) are electric fields that disrupt cancer cell division and have shown improved survival and safety in patients with glioblastoma and metastatic NSCLC. Phase 3 METIS trial [NCT02831959] aimed to evaluate the efficacy and safety of TTFields therapy in NSCLC patients with BM treated with SRS, specifically in terms of lengthening time to intracranial progression without cognitive decline. Methods: Mutation negative (M-) NSCLC patients with 1–10 BM were randomized 1:1 to receive stereotactic radiosurgery (SRS) followed by Tumor Treating Fields (TTFields; 150 kHz) therapy with best supportive care (BSC) or SRS followed by BSC. Patients with Karnofsky Performance Status (KPS) ≥70, newly diagnosed with one inoperable or 2–10 supra-/infratentorial brain metastases suitable for SRS and receiving optimal extracranial disease therapy were included. Exclusions were prior WBRT and single operable or recurrent brain metastases. Primary endpoint was time to first intracranial progression (RANO-BM) based on cumulative risk. Patients were followed every two months until second intracranial progression. Cognition and patient quality of life (QoL) were evaluated. Results: Between July 2016 and September 2022, 298 patients were randomized. Baseline characteristics were balanced: median age was 63.5 (range 37-84) years, 37.6% females, majority of patients had a KPS ≥ 80, median time from initial NSCLC diagnosis was 1.8 months (range: 0.2-55.7), 77% had adenocarcinoma. Median treatment duration of TTFields was 16 weeks, with a median usage time of 67%. Primary endpoint, time to intracranial progression from SRS, was significantly prolonged with SRS followed by TTFields therapy with BSC vs. TTFields plus BSC arm (median of 21.9 vs. 11.3 months); HR=0.67 [0.48-0.93], p=0.02. TTFields-related AEs were mainly dermatological, and Grade ≤2. TTFields therapy also improved deterioration-free survival of global health status, physical functioning, and fatigue according to QoL, and did not negatively impact cognition. Conclusions: METIS study met its primary endpoint, demonstrating that TTFields therapy following SRS in mutation negative NSCLC patients with BM, significantly prolongs time to intracranial progression and could postpone WBRT, without QoL and cognition decline. Clinical trial information: NCT02831959 .

A phase 2 trial of the CDK4 inhibitor dalpiciclib in well-differentiated or dedifferentiated liposarcoma.

11547 Background: The oncogene cyclin-dependent kinase 4 (CDK4) is amplified in > 90% of well-differentiated liposarcomas (WDLS) and dedifferentiated liposarcomas (DDLS). Previous studies have already demonstrated the clinical benefit of CDK4 inhibitors in the treatment of WDLS and DDLS. Dalpiciclib is a more potent and novel CDK4 inhibitor. We designed a multi-center phase 2 study to evaluate the safety and efficacy of dalpiciclib in patients with advanced WDLS/DDLS. Methods: Eligible patients were adults aged 18 years and older, with a confirmed diagnosis of advanced WDLS/DDLS, measurable lesions according to RECIST 1.1, any (or no) priory therapy, and a history of progression by RECIST 1.1 in the 6 months prior to enrollment. All patients were required to have CDK4 amplification by fluorescence in situ hybridization and retinoblastoma (RB) protein expression by immunohistochemistry. All patients were treated with dalpiciclib 150 mg orally once per day for 21 consecutive days within a 28-day treatment cycle. The primary endpoint was progression free survival (PFS) at 12 weeks. Secondary end points included objective response rate and adverse events. Results: From August 2022 to October 2023, a total of 32 patients were enrolled, and 30 were evaluable for the primary end point. Median (range) age was 59 (40-76) years; 22 patients (69%) were male. At 12 weeks, PFS was 61.3% (95% CI, 44-78.5%). The median PFS was 17.4 weeks (95% CI, 10.65-24.15 weeks). Only one patient had a partial response to the treatment. Grade 3 to 4 events included neutropenia (37.5%), anemia (6.25%), thrombocytopenia (6.25%), and nausea (3.13%). Conclusions: Treatment with the CDK4 inhibitor dalpiciclib was associated with a favorable PFS rate in patients with advanced CDK4-amplified and RB-expressing WDLS/DDLS. Clinical trial information: ChiCTR2200062868.

Anlotinib plus chemotherapy as first-line therapy for patients with gastrointestinal tumor with unresectable liver metastasis: Updated results from a multi-cohort, multi-center phase II trial, ALTER-G-001-cohort C.

e16304 Background: Advanced gastrointestinal (GI) tumors, such as colorectal, gastric and pancreatic cancers (CRC, GC, and PC), and esophageal squamous cell carcinoma (ESCC), 20%-50% with liver metastases (LMs) have a poor prognosis. Previous trials showed that anlotinib plus chemotherapy has promising clinical activity and a tolerable safety profile for advanced CRC and ESCC, especially with LMs. In this phase II trial, we assessed the efficacy and safety of anlotinib plus chemotherapy as first-line treatment for LMs GI tumors. Methods: Patients with unresectable LMs GI tumors and without previous systemic treatment would be divided into cohort A (CRC), cohort B (ESCC), and cohort C (other GI tumors, such as PC, GC, biliary tract cancer (BTC), etc.). In cohort C, patients received induction therapy: anlotinib plus standard chemotherapy. Patients without progressive disease (PD) and radical resection received anlotinib and metronomic capecitabine (500 mg, PO, BID, days 1-21, q3w) maintenance until PD or unacceptable toxicity. The primary endpoint was objective response rate (ORR) per RECIST v1.1. Secondary endpoints were duration of response (DoR), progression-free survival (PFS), overall survival (OS), disease control rate (DCR), time to response (TTR), depth of response (DpR), radical resection rate for LMs, and safety. Results: As of November 30, 2023, 44 patients were enrolled in cohort C (32 PC, 6 GC, 5 BTC, and others), the median age was 63.5 years (34-74), 65.9% male, 93.2% ECOG-PS 1 and 56.8% had LMs only. The majority of the pancreatic cancer patients (90.6%) received gemcitabine plus nab-paclitaxel chemotherapy combination with anlotinib as induction therapy. After induction therapy, 4 patients (1 PC, 2 GC, 1 BTC) received surgical resection. Of 37 evaluable patients in cohort C, 14 had partial response (PR), 18 had stable disease (SD) and 15 SD with reduced tumor size. The confirmed ORR was 37.8%, DCR was 86.5%. Of 25 evaluable pancreatic cancer patients, confirmed ORR and DCR were 36% (9/25) and 88% (22/25) respectively. In patients with pancreatic cancer, all PRs with DpR ≥30% and DpR ≥50% were 6 (66.7%). According to the Kaplan-Meier method, the median DoR was 4.6 (95%CI, 2.89-NE) months and PFS was 5.8 (95%CI, 4.1-6.0) months. The median TTR was 1.6 (range, 1.2-3.5) months. 36 patients in cohort C had TRAEs and ≥ grade 3 TRAEs (45.5%) mainly included hypertension (11.4%), neutropenia (9.1%), and blood platelet decreased (9.1%). Conclusions: Anlotinib plus chemotherapy as first-line treatment has shown promising efficacy and acceptable safety and maybe a favorable option for advanced LMs GI tumors, especially for pancreatic cancer. Clinical trial information: NCT05262335 .

Utidelone plus bevacizumab for the treatment of HER2-negative breast cancer brain metastases (U-BOMB): A multicenter, single-arm phase II study.

1081 Background: The primary treatment for brain metastases in patients with HER2-negative advanced breast cancer is predominantly local therapies like radiotherapy, owing to the limited efficacy of systemic therapies. Prior research has demonstrated utidelone's significant permeability across the blood-brain barrier and the preliminary effectiveness of bevacizumab for breast cancer brain metastases. Consequently, this study investigated the efficacy and safety of utidelone combined with bevacizumab in the treatment of advanced breast cancer brain metastases. Methods: This study was a single-arm, multi-center phase II clinical trial (NCT05357417). Eligible patients were aged 18 years or older with either radiotherapy-naive or progressive brain metastases post-radiotherapy, presented with asymptomatic or symptomatic brain metastases associated with HER2-negative breast cancer.Patients received intravenous bevacizumab (15 mg/kg on day 1 of each 3-week cycle) and utidelone (30 mg/m2 on days 1 to 5 of each cycle) until intolerance or disease progression. The primary endpoint was central nervous system objective response rate (CNS-ORR), as assessed according to the Response Evaluation Criteria In Solid Tumors version 1.1. Results: Between May 5, 2022, and October 25, 2023, a total of 46 patients were recruited, with a median age of 52.5 years (range, 33 to 69). Among them, 35 patients had untreated CNS lesions, while 11 had progressive brain metastases after local radiotherapy. The CNS-ORR was 43.5% (95% confidence interval [CI], 28.9%-58.9%). As of January 8, 2024, the median duration of follow-up was 14.6 months, and the median progression-free survival (PFS) was 7.7 months (95% CI: 5.5-10.8) as shown in Table. The 12-month overall survival (OS) rate reached 74.4% (95% CI: 60.0%-92.3%). The most common grade 1-2 adverse events (AEs) were peripheral neuropathy (87.5%), decreased neutrophil count (62.5%), anemia (47.5%), diarrhea (37.5%), and increased alanine aminotransferase (25%). No grade 3 or higher treatment-related AEs occurred. Conclusions: This study preliminarily shows promising efficacy and manageable safety of the combination of utidelone and bevacizumab in the treatment of HER2-negative metastatic breast cancer patients with brain metastases. Clinical trial information: NCT05357417 . [Table: see text]

Preoperative (neoadjuvant) therapy with tislelizumab for locally advanced colorectal cancer with high microsatellite instability or deficient mismatch repair: An open-label, single-arm, multicenter phase II study.

3599 Background: Tislelizumab (TIS), an anti-programmed cell death protein 1 (PD-1) antibody, demonstrated improved anti-tumor response and tolerable safety in patients (pts) with previously treated, locally advanced unresectable or metastatic microsatellite instability high/deficient mismatch repair (MSI-H/dMMR) solid tumors, including colorectal cancer (CRC; NCT03736889). Recent studies of other anti-PD-1 antibodies indicate potential clinical benefit of neoadjuvant anti-PD-1 therapy in pts with resectable MSI-H/dMMR CRC. Here, we report efficacy and safety outcomes of neoadjuvant TIS from a multicenter phase II trial (NCT05116085) in this population. Methods: Pts aged ≥18 years with stage II/III MSI-H/dMMR CRC, ECOG PS 0-1, evaluable disease per RECIST v1.1, and eligible for R0 (complete) resection were enrolled. Pts received TIS 200 mg IV every 3 weeks for 3 cycles followed by surgical resection within 10 weeks of first TIS dose. The primary endpoint was major pathological response (MPR) rate (proportion of pts with ≤10% residual viable tumor in the surgically resected primary tumor). Secondary endpoints included pathological complete response (pCR) rate (proportion of pts with absence of residual tumor in the surgically resected specimen), and safety. The R0 resection rate was an exploratory endpoint. Results: Overall, 33 pts were enrolled across eight sites in China. The median age of enrolled pts was 52.0 years (range: 23-84), 14 (42.4%) pts were male. Ten (30.3%) pts had rectal cancer and 23 (69.7%) colon cancer. At study entry, clinical tumor (T) stage was reported as T2, T3, and T4 in 1 (3.0%), 7 (21.2%), and 25 (75.8%) pts, respectively, and node (N) stage as N0, N1, and N2 in 6 (18.2%), 14 (42.4%), and 13 (39.4%) pts, respectively. All pts had a metastasis (M) stage of M0. A total of 29 (87.9%) pts underwent surgery and were evaluable for efficacy endpoints. Surgery was not performed in 4 pts, 3 of whom were managed non-operatively (1 pt had progressive disease). MPR and pCR rates were 89.7% and 62.1%, respectively (Table). Any-grade and grade ≥3 TIS-related adverse events (TRAEs) were reported in 20 (60.6%) and 1 (3.0%) pts, respectively. Two (6.1%) pts experienced serious TRAEs; no TRAEs led to death or surgery cancellation. One pt (3.0%) experienced a TRAE (grade 2 hypothyroidism) leading to surgery delay. No grade ≥3 or serious TIS-related surgery-relevant adverse events were reported. Immune-mediated adverse events were reported in 10 (30.3%) pts (all grade 1-2). Conclusions: Neoadjuvant TIS was associated with high MPR and pCR rates and an acceptable safety profile, and did not compromise surgery in pts with resectable MSI-H/dMMR CRC. Clinical trial information: NCT05116085 . [Table: see text]