A Phase II Clinical Study on the Efficacy of Stereotactic Body Radiation Therapy Sequential Combined With Bevacizumab and Trifluridine/Tipiracil in the Treatment of Recurrent Metastatic Colorectal Cancer(BEST)
试验速览
- 阶段
- 2 期
- 状态
- 尚未招募
- 发起方
- 入组人数
- 58
- 试验地点
- 1
- 主要终点
- Progression-Free Survival (PFS)
研究概览
简要总结
This phase II trial studies how well stereotactic body radiotherapy (SBRT) followed by a combination of an immune checkpoint inhibitor (sintilimab), bevacizumab, and trifluridine/tipiracil (TAS-102) works as third-line treatment for patients with recurrent or metastatic colorectal cancer (mCRC) that has progressed after at least two prior lines of systemic therapy.
The study will enroll 58 participants at Zhongshan Hospital, Fudan University. Participants will be randomly assigned (1:1) to either the experimental group or the control group. Those in the experimental group will receive SBRT to lung or liver metastases, followed one week later by sintilimab (200 mg every 2 weeks), bevacizumab (5 mg/kg every 2 weeks), and TAS-102 (35 mg/m² twice daily on days 1-5 every 2 weeks). Those in the control group will receive the investigator's choice of standard third-line therapy (such as TAS-102 alone or with bevacizumab, regorafenib, or fruquintinib).
The main purpose is to see whether the new combination extends the time without the cancer growing or spreading (progression-free survival, PFS). Other goals include measuring overall survival, tumor response rates, local control of treated tumors, abscopal (out-of-field) effects, safety, quality of life, and exploring biomarkers that might predict treatment response.
The study is expected to take 24 months to complete (12 months for enrollment and 12 months for follow-up). Results will help determine if adding SBRT and immunotherapy to standard chemotherapy and anti-angiogenic therapy is a beneficial option for patients with refractory mCRC.
详细描述
Background and Rationale Colorectal cancer (CRC) is the third most common malignancy worldwide. Approximately 40-50% of patients develop metastatic disease (mCRC). For patients who progress after first- and second-line systemic therapy (including fluoropyrimidines, oxaliplatin, irinotecan, and anti-VEGF or anti-EGFR antibodies where indicated), third-line treatment options remain limited. Currently approved agents such as regorafenib, fruquintinib, and trifluridine/tipiracil (TAS-102) provide modest benefit, with median progression-free survival (PFS) of approximately 2-3 months and objective response rates below 5%. Moreover, the vast majority (90-95%) of mCRC patients have microsatellite stable (MSS) or proficient mismatch repair (pMMR) tumors, which are largely unresponsive to immune checkpoint inhibitor monotherapy.
Preclinical and emerging clinical evidence suggests that stereotactic body radiotherapy (SBRT) can induce immunogenic cell death, remodel the tumor immune microenvironment, and synergize with immune checkpoint inhibitors. Additionally, bevacizumab (anti-VEGF) has immunomodulatory effects, including reducing regulatory T cells and M2-type tumor-associated macrophages, and promoting dendritic cell maturation. The phase III SUNLIGHT trial demonstrated that adding bevacizumab to TAS-102 significantly improved overall survival (10.8 vs. 7.5 months) and PFS (5.6 vs. 2.4 months) in refractory mCRC. Therefore, combining SBRT with PD-1 inhibitor, bevacizumab, and TAS-102 may further enhance antitumor immunity and improve clinical outcomes in MSS/pMMR mCRC patients.
Study Design This is a prospective, single-center, randomized, open-label, phase II trial. A total of 58 eligible patients will be randomized 1:1 to either the experimental arm or the control arm. Randomization will be performed using a computer-generated random sequence. No blinding is applied.
Interventions
- Experimental arm: Patients will first receive SBRT to metastatic lung or liver lesions. SBRT is delivered using image-guided radiotherapy. The fractionation schedule is tailored to tumor location, with a biologically effective dose (BED) ≥94 Gy, completed within 1-2 weeks. One week after completion of SBRT, patients start systemic therapy: sintilimab (200 mg intravenously every 2 weeks), bevacizumab (5 mg/kg intravenously every 2 weeks), and TAS-102 (35 mg/m² orally twice daily on days 1-5 of each 14-day cycle). Treatment continues until disease progression, unacceptable toxicity, patient withdrawal, or other protocol-specified discontinuation criteria.
- Control arm: Patients receive investigator's choice of standard-of-care third-line therapy for mCRC, which may include TAS-102 monotherapy, TAS-102 plus bevacizumab, regorafenib, or fruquintinib, according to local clinical practice and Chinese Society of Clinical Oncology (CSCO) guidelines.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- None
入排标准
- 年龄范围
- 18 Years 至 75 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Age 18 to 75 years (inclusive).
- •Eastern Cooperative Oncology Group (ECOG) performance status 0 or
- •Histologically or cytologically confirmed colorectal cancer with unresectable metastatic or recurrent lesions.
- •Has received at least first- and second-line systemic anti-tumor therapy for metastatic colorectal cancer (chemotherapy regimens may include fluoropyrimidines, oxaliplatin, irinotecan, with or without targeted agents such as bevacizumab or cetuximab) and has progressed after second-line therapy.
- •Has evaluable lung or liver metastases amenable to stereotactic body radiotherapy (SBRT).
- •Has at least one measurable lesion according to RECIST v1.
- •Female patients of childbearing potential must have a negative urine or serum pregnancy test within ≤7 days before first dose of study drug. All fertile patients must agree to use highly effective contraception during the study and for ≥120 days after the last dose.
- •Willing and able to provide written informed consent.
排除标准
- •Laboratory abnormalities: absolute neutrophil count <1.5×10⁹/L, platelet count <100×10⁹/L, hemoglobin <9 g/dL; total bilirubin >1.5× upper limit of normal (ULN) (>2.5× ULN for patients with liver metastases); AST/ALT >2.5× ULN (>5× ULN for patients with liver metastases); serum creatinine >1.5× ULN or creatinine clearance <60 mL/min; APTT or PT >1.5× ULN; albumin <30 g/L; clinically significant electrolyte abnormalities. Transfusion or growth factor support within 2 weeks before enrollment to meet eligibility is not permitted.
- •Prior evidence of deficient mismatch repair (dMMR), microsatellite instability-high (MSI-H), or BRAF mutation by histology or ctDNA testing.
- •Prior immunotherapy (anti-PD-1, anti-PD-L1, anti-CTLA-4, or any cellular immunotherapy).
- •Active or history of autoimmune disease that may relapse.
- •Requires systemic corticosteroids (>10 mg/day prednisone equivalent) or other immunosuppressive drugs within 14 days before first dose of study drug (exceptions allowed for low-dose steroids, topical/inhaled steroids, or short-term prophylaxis).
- •History of interstitial lung disease, non-infectious pneumonitis, pulmonary fibrosis, acute lung disease, or poorly controlled systemic disease (e.g., diabetes, hypertension).
- •Clinically uncontrolled diarrhea.
- •Severe chronic or active infection requiring systemic antimicrobial therapy, including tuberculosis.
- •Brain or leptomeningeal metastases.
- •Clinically significant pleural effusion, pericardial effusion, or ascites requiring repeated drainage within 2 weeks before first dose.
- •Presence of clinically detectable second primary malignancy or other malignancy within the past 5 years (except adequately treated basal cell carcinoma of the skin or cervical carcinoma in situ).
- •Poorly controlled diabetes or electrolyte disturbances despite standard medical management.
- •Known HIV infection.
- •Untreated chronic hepatitis B (HBV DNA >500 IU/mL) or detectable hepatitis C virus (HCV) RNA. Inactive HBsAg carriers, treated and stable hepatitis B (HBV DNA ≤500 IU/mL), and cured hepatitis C are allowed.
- •Major surgery within ≤28 days before first dose.
- •Prior allogeneic stem cell or organ transplantation.
- •Uncontrolled hypertension (systolic ≥140 mmHg or diastolic >90 mmHg on monotherapy).
- •Active gastrointestinal diseases (e.g., duodenal ulcer, ulcerative colitis, intestinal obstruction) or history of intestinal perforation/fistula not fully healed after surgery.
- •History of arterial or deep vein thrombosis within 6 months before enrollment, or bleeding tendency/bleeding history within 2 months before enrollment regardless of severity.
- •Stroke or transient ischemic attack within 12 months before enrollment; non-healing skin wound, surgical site, trauma, severe mucosal ulcer, or fracture; acute myocardial infarction, severe/unstable angina, or coronary artery bypass graft within 6 months; New York Heart Association (NYHA) class ≥2 heart failure.
- •Severe hypersensitivity to other monoclonal antibodies, trifluridine/tipiracil, or any excipient.
- •Received systemic chemotherapy within 28 days before first dose, or immunotherapy/hormonal therapy/targeted therapy/investigational therapy within 14 days or 5 half-lives (whichever is shorter).
- •Received Chinese herbal medicine or proprietary Chinese medicine for cancer control within 14 days before first dose.
- •Toxicities from prior anticancer therapy not recovered to baseline or stable level (except alopecia, neuropathy, and specific laboratory abnormalities deemed not a safety risk).
- •Received live vaccine within 4 weeks before first dose.
- •Any clinical or laboratory abnormality or compliance issue that, in the investigator's judgment, makes the patient unsuitable for the study.
- •Severe psychological or mental abnormalities.
研究组 & 干预措施
SBRT followed by triple therapy
Patients receive stereotactic body radiotherapy (SBRT) to metastatic lung or liver lesions with a biologically effective dose (BED) ≥94 Gy, completed within 1-2 weeks. One week after SBRT, patients receive sintilimab 200 mg intravenously (IV) every 2 weeks (Q2W), bevacizumab 5 mg/kg IV Q2W, and trifluridine/tipiracil (TAS-102) 35 mg/m² orally twice daily on days 1-5 of each 14-day cycle. Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or other protocol-specified discontinuation criteria.
干预措施: SBRT (Radiation)
Standard of Care (SOC)
Patients receive investigator's choice of standard-of-care third-line therapy for metastatic colorectal cancer, which may include trifluridine/tipiracil (TAS-102) monotherapy, TAS-102 plus bevacizumab, regorafenib, or fruquintinib, administered according to local clinical practice and Chinese Society of Clinical Oncology (CSCO) guidelines. Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or other protocol-specified discontinuation criteria.
干预措施: Standard of Care (Investigator Selected) (Drug)
SBRT followed by triple therapy
Patients receive stereotactic body radiotherapy (SBRT) to metastatic lung or liver lesions with a biologically effective dose (BED) ≥94 Gy, completed within 1-2 weeks. One week after SBRT, patients receive sintilimab 200 mg intravenously (IV) every 2 weeks (Q2W), bevacizumab 5 mg/kg IV Q2W, and trifluridine/tipiracil (TAS-102) 35 mg/m² orally twice daily on days 1-5 of each 14-day cycle. Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or other protocol-specified discontinuation criteria.
干预措施: Bevacizumab (Drug)
SBRT followed by triple therapy
Patients receive stereotactic body radiotherapy (SBRT) to metastatic lung or liver lesions with a biologically effective dose (BED) ≥94 Gy, completed within 1-2 weeks. One week after SBRT, patients receive sintilimab 200 mg intravenously (IV) every 2 weeks (Q2W), bevacizumab 5 mg/kg IV Q2W, and trifluridine/tipiracil (TAS-102) 35 mg/m² orally twice daily on days 1-5 of each 14-day cycle. Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or other protocol-specified discontinuation criteria.
干预措施: Sintilimab (Drug)
SBRT followed by triple therapy
Patients receive stereotactic body radiotherapy (SBRT) to metastatic lung or liver lesions with a biologically effective dose (BED) ≥94 Gy, completed within 1-2 weeks. One week after SBRT, patients receive sintilimab 200 mg intravenously (IV) every 2 weeks (Q2W), bevacizumab 5 mg/kg IV Q2W, and trifluridine/tipiracil (TAS-102) 35 mg/m² orally twice daily on days 1-5 of each 14-day cycle. Treatment continues until disease progression, unacceptable toxicity, withdrawal of consent, or other protocol-specified discontinuation criteria.
干预措施: Trifluridine and Tipiracil Tablets (Drug)
结局指标
主要结局
Progression-Free Survival (PFS)
时间窗: Up to 24 months
Time from randomization to first documented radiographic disease progression per RECIST v1.1 or death from any cause, whichever occurs first.
次要结局
- Overall Survival (OS)(Up to 36 months)