QL1706 With Short-Course Radiotherapy and Chemotherapy for MSS Rectal Cancer

Summary

This is a multicenter, prospective, phase II study evaluating total neoadjuvant therapy (TNT) consisting of short-course radiotherapy (SCRT; 5×5 Gy) followed by QL1706 (a bifunctional MabPair antibody targeting PD-1 and CTLA-4, code name only) plus mFOLFOX6 chemotherapy in patients with locally advanced rectal cancer (LARC) with proficient mismatch repair/microsatellite-stable (pMMR/MSS) biology. Patients with pMMR/MSS disease derive limited benefit from immune checkpoint inhibition alone. Preclinical and clinical evidence suggests that SCRT and oxaliplatin-based chemotherapy can enhance antitumor immunity (e.g., antigen release, T-cell infiltration), providing a biological rationale for combining QL1706 with SCRT-primed TNT. Eligible adults with cT3-4 and/or N+ mid-to-low rectal adenocarcinoma (without distant metastasis), confirmed pMMR/MSS, and ECOG 0-1 will receive: SCRT (total 25 Gy over 5 fractions), then several cycles of QL1706 plus mFOLFOX6 as neoadjuvant systemic therapy. Definitive total mesorectal excision (TME) is planned per multidisciplinary assessment; a watch-and-wait approach may be considered for patients achieving a stringent clinical complete response per institutional criteria. Standard perioperative care and postoperative follow-up will be performed. Primary endpoint is pathologic complete response (pCR, ypT0N0) rate at surgery. Key secondary endpoints include: clinical complete response (cCR) rate, major pathologic response rate, R0 resection rate, tumor downstaging, radiologic response, disease-free survival (DFS), overall survival (OS), organ preservation rate (for patients managed non-operatively), surgical morbidity, and safety/tolerability (CTCAE v5.0). Exploratory endpoints include correlations between efficacy and baseline clinicopathologic features; optional translational analyses may investigate immune-inflammation markers related to response and resistance. This trial aims to determine whether SCRT-primed QL1706 plus mFOLFOX6 TNT can improve tumor eradication and organ preservation while maintaining acceptable safety in pMMR/MSS LARC-a population with unmet need for effective immunotherapy-based strategies.

Timeline

Start

2025-09-20

Primary completion

2026-09-20

Completion

2029-09-20

Publications

• Results Xiao WW, Chen G, Gao YH, Lin JZ, Wu XJ, Luo HL, Lu ZH, Wang QX, Sun R, Cai PQ, Zhu CM, Liu M, Li JB, Wang YR, Jin Y, Wang F, Luo HT, Li CL, Pan ZZ, Xu RH. Effect of neoadjuvant chemoradiotherapy with or without PD-1 antibody sintilimab in pMMR locally advanced rectal cancer: A randomized clinical trial. Cancer Cell. 2024 Sep 9;42(9):1570-1581.e4. doi: 10.1016/j.ccell.2024.07.004. Epub 2024 Aug 1.
• Results Lin ZY, Zhang P, Chi P, Xiao Y, Xu XM, Zhang AM, Qiu XF, Wu JX, Yuan Y, Wang ZN, Qu XJ, Li X, Nie X, Yang M, Cai KL, Zhang WK, Huang Y, Sun Z, Hou ZG, Ma C, Cheng FZ, Tao KX, Zhang T. Neoadjuvant short-course radiotherapy followed by camrelizumab and chemotherapy in locally advanced rectal cancer (UNION): early outcomes of a multicenter randomized phase III trial. Ann Oncol. 2024 Oct;35(10):882-891. doi: 10.1016/j.annonc.2024.06.015. Epub 2024 Jul 2.
• Results Fakih M, Sandhu J, Lim D, Li X, Li S, Wang C. Regorafenib, Ipilimumab, and Nivolumab for Patients With Microsatellite Stable Colorectal Cancer and Disease Progression With Prior Chemotherapy: A Phase 1 Nonrandomized Clinical Trial. JAMA Oncol. 2023 May 1;9(5):627-634. doi: 10.1001/jamaoncol.2022.7845.
• Results Versluis JM, Long GV, Blank CU. Learning from clinical trials of neoadjuvant checkpoint blockade. Nat Med. 2020 Apr;26(4):475-484. doi: 10.1038/s41591-020-0829-0. Epub 2020 Apr 9.
• Results Cercek A, Lumish M, Sinopoli J, Weiss J, Shia J, Lamendola-Essel M, El Dika IH, Segal N, Shcherba M, Sugarman R, Stadler Z, Yaeger R, Smith JJ, Rousseau B, Argiles G, Patel M, Desai A, Saltz LB, Widmar M, Iyer K, Zhang J, Gianino N, Crane C, Romesser PB, Pappou EP, Paty P, Garcia-Aguilar J, Gonen M, Gollub M, Weiser MR, Schalper KA, Diaz LA Jr. PD-1 Blockade in Mismatch Repair-Deficient, Locally Advanced Rectal Cancer. N Engl J Med. 2022 Jun 23;386(25):2363-2376. doi: 10.1056/NEJMoa2201445. Epub 2022 Jun 5.
• Results Chalabi M, Fanchi LF, Dijkstra KK, Van den Berg JG, Aalbers AG, Sikorska K, Lopez-Yurda M, Grootscholten C, Beets GL, Snaebjornsson P, Maas M, Mertz M, Veninga V, Bounova G, Broeks A, Beets-Tan RG, de Wijkerslooth TR, van Lent AU, Marsman HA, Nuijten E, Kok NF, Kuiper M, Verbeek WH, Kok M, Van Leerdam ME, Schumacher TN, Voest EE, Haanen JB. Neoadjuvant immunotherapy leads to pathological responses in MMR-proficient and MMR-deficient early-stage colon cancers. Nat Med. 2020 Apr;26(4):566-576. doi: 10.1038/s41591-020-0805-8. Epub 2020 Apr 6.
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• Results Schrag D, Weiser MR, Goodman KA, Gonen M, Hollywood E, Cercek A, Reidy-Lagunes DL, Gollub MJ, Shia J, Guillem JG, Temple LK, Paty PB, Saltz LB. Neoadjuvant chemotherapy without routine use of radiation therapy for patients with locally advanced rectal cancer: a pilot trial. J Clin Oncol. 2014 Feb 20;32(6):513-8. doi: 10.1200/JCO.2013.51.7904. Epub 2014 Jan 13.
• Results Fernandez-Martos C, Pericay C, Aparicio J, Salud A, Safont M, Massuti B, Vera R, Escudero P, Maurel J, Marcuello E, Mengual JL, Saigi E, Estevan R, Mira M, Polo S, Hernandez A, Gallen M, Arias F, Serra J, Alonso V. Phase II, randomized study of concomitant chemoradiotherapy followed by surgery and adjuvant capecitabine plus oxaliplatin (CAPOX) compared with induction CAPOX followed by concomitant chemoradiotherapy and surgery in magnetic resonance imaging-defined, locally advanced rectal cancer: Grupo cancer de recto 3 study. J Clin Oncol. 2010 Feb 10;28(5):859-65. doi: 10.1200/JCO.2009.25.8541. Epub 2010 Jan 11.
• Results Cercek A, Goodman KA, Hajj C, Weisberger E, Segal NH, Reidy-Lagunes DL, Stadler ZK, Wu AJ, Weiser MR, Paty PB, Guillem JG, Nash GM, Temple LK, Garcia-Aguilar J, Saltz LB. Neoadjuvant chemotherapy first, followed by chemoradiation and then surgery, in the management of locally advanced rectal cancer. J Natl Compr Canc Netw. 2014 Apr;12(4):513-9. doi: 10.6004/jnccn.2014.0056.
• Results Bosset JF, Calais G, Mineur L, Maingon P, Stojanovic-Rundic S, Bensadoun RJ, Bardet E, Beny A, Ollier JC, Bolla M, Marchal D, Van Laethem JL, Klein V, Giralt J, Clavere P, Glanzmann C, Cellier P, Collette L; EORTC Radiation Oncology Group. Fluorouracil-based adjuvant chemotherapy after preoperative chemoradiotherapy in rectal cancer: long-term results of the EORTC 22921 randomised study. Lancet Oncol. 2014 Feb;15(2):184-90. doi: 10.1016/S1470-2045(13)70599-0. Epub 2014 Jan 17.
• Results Bosset JF, Collette L, Calais G, Mineur L, Maingon P, Radosevic-Jelic L, Daban A, Bardet E, Beny A, Ollier JC; EORTC Radiotherapy Group Trial 22921. Chemotherapy with preoperative radiotherapy in rectal cancer. N Engl J Med. 2006 Sep 14;355(11):1114-23. doi: 10.1056/NEJMoa060829.
• Results Pucciarelli S, Del Bianco P, Efficace F, Serpentini S, Capirci C, De Paoli A, Amato A, Cuicchi D, Nitti D. Patient-reported outcomes after neoadjuvant chemoradiotherapy for rectal cancer: a multicenter prospective observational study. Ann Surg. 2011 Jan;253(1):71-7. doi: 10.1097/SLA.0b013e3181fcb856.
• Results Cunningham D, Atkin W, Lenz HJ, Lynch HT, Minsky B, Nordlinger B, Starling N. Colorectal cancer. Lancet. 2010 Mar 20;375(9719):1030-47. doi: 10.1016/S0140-6736(10)60353-4.
• Results Sauer R, Becker H, Hohenberger W, Rodel C, Wittekind C, Fietkau R, Martus P, Tschmelitsch J, Hager E, Hess CF, Karstens JH, Liersch T, Schmidberger H, Raab R; German Rectal Cancer Study Group. Preoperative versus postoperative chemoradiotherapy for rectal cancer. N Engl J Med. 2004 Oct 21;351(17):1731-40. doi: 10.1056/NEJMoa040694.
• Results Siegel RL, Miller KD, Fuchs HE, Jemal A. Cancer Statistics, 2021. CA Cancer J Clin. 2021 Jan;71(1):7-33. doi: 10.3322/caac.21654. Epub 2021 Jan 12.

Drugs

Indications