Safety and Efficacy of Whole Brain LDRT+ICI+Intrathecal Chemotherapy in Refractory Meningeal Metastasis of Lung Cancer

Phase I Study of Whole Brain Low Dose Radiotherapy Combined With ICI and Intrathecal Chemotherapy for Treatment of Refractory Meningeal Metastasis of Lung Cancer

Safety and Efficacy of Whole Brain LDRT+ICI+Intrathecal Chemotherapy in Refractory Meningeal Metastasis of Lung Cancer (NCT06431685) is a Phase 1 interventional studying NSCLC and Low Dose Radiotherapy, sponsored by Sichuan University. RECRUITING as of the most recent ClinicalTrials.gov update. Talk to your doctor before contacting the trial site.

About This Trial

What Stage of Research Is This?

Phase 1 trials test a new treatment for the first time in humans, focusing on safety, dosing, and how the body processes the drug. For NSCLC, a Phase 1 study typically enrolls a small number of participants — often healthy volunteers or patients who have exhausted standard treatment options. Phase 1 results determine whether a treatment moves into larger Phase 2 efficacy studies.

This trial is currently recruiting participants. The sponsor has registered the study with ClinicalTrials.gov as actively enrolling, which means new applicants who meet the eligibility criteria can be considered for screening. Trial status can change between updates — confirm current recruiting status with the study contact before traveling for a screening visit.

With a target enrollment of 10 participants, this is a small study — typical of early-phase research, rare-disease trials, or pilot studies designed to generate preliminary signal before a larger study is launched.

Who May Be Eligible (Plain English)

Who May Qualify: 1. ≥ 18 years old and ≤ 75 years old; 2. Patients with a definite diagnosis of leptomeningeal metastasis by cerebrospinal fluid cytology, or patients with clinical diagnosis combined with tumor history, neuroimaging, clinical manifestations, cerebrospinal fluid examination, etc.; 3. Patients with a clear history of lung carcinoma, including histopathological diagnosis or a combination of cytopathology and imaging, and failure of standard treatment; 4. Efficacy of extracranial lesions SD; 5. Patients with no contraindications to craniocranial radiotherapy were judged by radiotherapy doctors. Subjects who agree to receive immunotherapy, Lumbar puncture, intrathecal chemotherapy, and radiotherapy; 6. Expected survival ≥3 months, PS score ≤3; 7. Agree to provide cerebrospinal fluid, blood and tissue samples for biomarker testing; 8. The main organs function normally, no serious blood, heart, lung, liver, kidney, bone marrow and other functional abnormalities and immune deficiency diseases; 9. One week before enrollment, bone marrow and liver and kidney function met the following criteria: ① blood count (hemoglobin) at least 80 g/L, neutrophils ≥1.5×10\^9/L and platelet count at least 70×10\^9/L; ② Renal function: Cr≤ULN (upper limit of normal) × 1.5, endogenous creatinine clearance (Ccr)≥55 ml/min; Liver function: total bilirubin ≤ULN × 1.5; ALT, AST≤ULN × 2.5; (In case of liver metastasis, total bilirubin should not be higher than 3 times the upper normal limit, and transaminase should not be higher than 5 times the upper normal limit); 10. The fertile women agreed to use contraception during the study period and for 6 months after the study ended; Patients who tested negative for a serum or urine pregnancy test within 7 days prior to joining the study and were not breastfed; Men who agreed to use contraception during the study period and for 6 months after the study ended Who Should NOT Join This Trial: ...See full criteria on ClinicalTrials.gov Always talk to your doctor about whether this trial is right for you.

These are translations of the protocol\'s inclusion and exclusion criteria, simplified for patients and caregivers. The original clinical text appears below. Eligibility is ultimately confirmed by the trial site\'s screening process — this summary is a starting point for a conversation with your doctor, not a final determination.

Original Eligibility Criteria

View original clinical language

Inclusion Criteria: 1. ≥ 18 years old and ≤ 75 years old; 2. Patients with a definite diagnosis of leptomeningeal metastasis by cerebrospinal fluid cytology, or patients with clinical diagnosis combined with tumor history, neuroimaging, clinical manifestations, cerebrospinal fluid examination, etc.; 3. Patients with a clear history of lung carcinoma, including histopathological diagnosis or a combination of cytopathology and imaging, and failure of standard treatment; 4. Efficacy of extracranial lesions SD; 5. Patients with no contraindications to craniocranial radiotherapy were judged by radiotherapy doctors. Subjects who agree to receive immunotherapy, Lumbar puncture, intrathecal chemotherapy, and radiotherapy; 6. Expected survival ≥3 months, PS score ≤3; 7. Agree to provide cerebrospinal fluid, blood and tissue samples for biomarker testing; 8. The main organs function normally, no serious blood, heart, lung, liver, kidney, bone marrow and other functional abnormalities and immune deficiency diseases; 9. One week before enrollment, bone marrow and liver and kidney function met the following criteria: ① Hemoglobin ≥80 g/L, neutrophils ≥1.5×10\^9/L and platelets ≥70×10\^9/L; ② Renal function: Cr≤ULN (upper limit of normal) × 1.5, endogenous creatinine clearance (Ccr)≥55 ml/min; Liver function: total bilirubin ≤ULN × 1.5; ALT, AST≤ULN × 2.5; (In case of liver metastasis, total bilirubin should not be higher than 3 times the upper normal limit, and transaminase should not be higher than 5 times the upper normal limit); 10. The fertile women agreed to use contraception during the study period and for 6 months after the study ended; Patients who tested negative for a serum or urine pregnancy test within 7 days prior to joining the study and were not breastfed; Men who agreed to use contraception during the study period and for 6 months after the study ended Exclusion Criteria: 1. Active autoimmune disease or history of autoimmune diseases; 2. Congenital or acquired immunodeficiency; 3. Uncontrolled cardiac clinical symptoms or diseases; 4. Severe infection or severe comorbidities, such as bleeding peptic ulcer, ileus, heart failure, renal failure, or poorly controlled diabetes; 5. History of allogeneic organ transplantation or allogeneic hematopoietic stem cell transplantation; 6. Other systemic malignancies within the last 5 years; 7. Allergy to any test drug; 8. Uncontrolled epilepsy, neurological failure, or severe treatment-related neurological impairment, uncontrollable psychosis, and other conditions deemed unsuitable for inclusion by the investigator; 9. Pregnant and lactating women, subjects with reproductive capacity are unwilling to take effective contraceptive measures.

Treatments Being Tested

RADIATION

Whole Brain Low Dose Radiotherapy

Whole brain LDRT will be administered at 3 cohorts with increasing dose fractions: Group 1: 4 Gy/2f of one cycle; Group 2: 4 Gy/2f of two cycles (Q3w); Group 3: 4 Gy/2f of three cycles (Q3w). WB-LDRT will be administered in a 4 Gy of 2 fractions over two days, starting from Day 1 in the first cycle (a daily dose of 2 Gy, 4 Gy/2f for one cycle, once per three weeks, at minmum in one cycle and maximum in four cycles in total).

DRUG

Pemetrexed

Pemetrexed, 30 mg, intrathecal injection, once per three weeks, 4 cycles in total

DRUG

Sintilimab

PD-1 inhibitor (Sintilimab, dose as recommended in the instruction manual), intravenous infusion, once per three weeks, 4 cycles in total

DRUG

Chemotherapy

Pemetrexed at a dose of 500 mg/m\^2, intravenous infusion, once per three weeks, 4 cycles in total

Locations (1)

Trial sites listed on ClinicalTrials.gov for this study. Site activation status can vary — confirm with the specific site before traveling for a screening visit.

West China Hospital, Sichuan University

Chengdu, Sichuan, China

How to Talk to Your Doctor About This Trial

Bring the printable summary of this trial — including the NCT ID (NCT06431685), the sponsor (Sichuan University), and the key eligibility criteria — to your next appointment. Your doctor can review the inclusion and exclusion criteria against your medical history, lab values, and current treatments to assess whether you are likely to qualify. They can also help you weigh whether trial participation makes sense alongside your existing care plan.

Useful questions to walk through together: What does the trial protocol require beyond standard care? How long is the active treatment phase, and how long is follow-up? Are there study visits at sites I can reach? Who pays for the trial-specific procedures, and who pays for standard-of-care portions? See our 25 questions to ask about clinical trials guide for a more complete checklist.

Authoritative Sources

The official record for this trial lives on ClinicalTrials.gov — the federal registry maintained by the National Library of Medicine at NIH. For background on how this trial fits into the FDA approval pathway, see the FDA drug approval process. For oncology-specific guidance for patients considering trials, the National Cancer Institute publishes patient-oriented overviews. International trial registries are aggregated by the WHO ICTRP.

Frequently Asked Questions

What is the NCT06431685 clinical trial studying?

This phase I study aims to investigate the safety and efficacy of whole brain low dose radiotherapy (WB-LDRT) combined with ICI and intrathecal chemotherapy for treatment of refractory meningeal metastasis of lung cancer. The full protocol is registered on ClinicalTrials.gov and includes the primary outcome measures, eligibility criteria, and study endpoints.

Who can participate in NCT06431685?

Eligibility for this trial depends on the specific inclusion and exclusion criteria set by the sponsor. The plain-English summary above translates the most important criteria into accessible language; the official clinical text is preserved in the collapsible section underneath. Whether you fit any specific trial is a medical decision your doctor needs to confirm — bring the trial information to your treating physician for a full review against your medical history.

How do I contact the trial site for NCT06431685?

Contact information registered with ClinicalTrials.gov is shown in the sidebar of this page. Before reaching out, confirm with your treating physician that this trial is appropriate for your situation. The trial site will then walk you through the screening process to determine final eligibility.

Is participating in a clinical trial safe?

Clinical trials in the United States are regulated by the FDA and overseen by Institutional Review Boards (IRBs) that review the protocol for safety. Risk varies by trial — Phase 1 studies test new treatments in humans for the first time, while Phase 3 trials use treatments that have already passed earlier safety screening. The informed consent document for any specific trial details the known risks and what to expect. Discuss those risks with your physician before deciding whether to participate.

Where can I verify the data on this page?

Every detail on this page comes directly from the ClinicalTrials.gov API. Click "View on ClinicalTrials.gov" in the sidebar to see the official, unmodified record. The federal record is always authoritative; this page is a structured presentation with a plain-English eligibility translation. For background on how clinical trials are regulated, see the FDA drug approval process documentation.

How This Page Is Built

Every field on this page is pulled directly from the ClinicalTrials.gov API v2 — no estimates, no proxies. The plain-English eligibility translation is generated from the original protocol text and reviewed for fidelity to the underlying clinical criteria. The original clinical text remains visible in the collapsible section above so users and clinicians can verify the translation. Read the full methodology for the data pipeline and known limitations.

Source: ClinicalTrials.gov API v2 record for NCT06431685. Maintained by the National Library of Medicine at NIH. Public domain. Cite as: "TrialFinderData. NCT06431685. Data: ClinicalTrials.gov."

Medical disclaimer: This page is informational, not medical advice. Talk to your doctor about whether a clinical trial is right for you.

Last updated 2026-05-08 · Data from ClinicalTrials.gov.