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Recruiting Phase 1 NCT06259552

NCT06259552 A Study of SPX-303, a Bispecific Antibody Targeting LILRB2 and PD-L1 in Patients With Solid Tumors

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Clinical Trial Summary
NCT ID NCT06259552
Status Recruiting
Phase Phase 1
Sponsor SparX Biotech(Jiangsu) Co., Ltd.
Condition Solid Tumor
Study Type INTERVENTIONAL
Enrollment 232 participants
Start Date 2024-03-20
Primary Completion 2027-09

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
SPX- 303 Injection, a bispecific anti-LILRB2 / anti-PD-L1 Antibody

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 1 is the earliest stage of human testing — safety and dosage are the primary focus. Visits are frequent and medical supervision is intensive. You will be among the first people to receive this treatment.

This trial targets 232 participants in total. It began in 2024-03-20 with a primary completion date of 2027-09.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

Part 1 of this study is an open-label, dose-escalation, and safety expansion study of an anti-LILRB2 / anti-PD-L1 bispecific antibody SPX- 303 in patients with solid tumors. Part 2 of this study is an indication-specific dose expansion study of SPX-303.

Eligibility Criteria

Inclusion Criteria: 1. Males and females ≥18 years of age who comprehend, are not incarcerated, are willing and able to provide consent by signing an ICF, and able to comply with scheduled visits, treatment schedule, and laboratory tests, including other requirements for the study 2. Histologically or cytologically documented locally advanced or metastatic solid tumor malignancy 3. Patients who have progressed on or after prior therapy and who are not eligible for available treatment options 4. Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 5. Has at least 1 measurable lesion per RECIST 1.1 criteria 6. Recovery from previous treatment related adverse events (TRAEs) to allow safety evaluations of SPX-303. Previous TRAEs include adverse drug reactions, and consequences of radiation, surgery, and other therapeutic modalities 7. Adequate hepatic function; bilirubin ≤1.5x upper limit of normal (ULN) (except for patients with Gilbert syndrome: ≤ 3xULN), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) ≤2.5 x ULN (≤5 x ULN if liver metastases present). 8. Adequate renal function as calculated (e.g. Cockroft Gault) creatine clearance (CrCl) ≥ 30 mL/min or 24-hour urine CrCl ≥ 30 mL/min. 9. Adequate hematological function: absolute neutrophil count (ANC) ≥1 x 10\^9/L; platelets ≥75 x 10\^9/L, hemoglobin ≥9 g/dL. 10. Patients with well controlled HIV infection (ie CD4+ count \>350 cells/uL and viral copies less than 400/mL after at least 4 weeks of ART) are eligible for the trial. 11. Adequate coagulation function: INR, PT and aPPT ≤ 1.5x ULN except for patients on anti-coagulation as long as PT, aPPT, or INR are within intended range. 12. Adequate cardiac function: Left Ventricular Ejection Fraction (LVEF) ≥ 45% by multi-gated acquisition (MUGA) or echocardiography (ECHO) scan. 13. Fridericia-corrected QT interval (QTcF) ≤480 msec. 14. Women of childbearing potential must have a negative pregnancy test and must agree to use of 2 different methods of acceptable contraception from screening until 4 months after the last dose of study drug. Acceptable methods of contraception are defined as those that result, alone or in combination, in a low failure rate (ie, less than 1% per year) when used consistently and correctly, such as surgical sterilization, an intrauterine device, hormonal contraception in combination with a barrier method or abstinence). 15. Males who are sexually active with a female partner of childbearing potential must agree to use a barrier contraception (eg, condom with spermicidal foam/gel/film/cream/suppository) from screening until 4 months following the last dose of study drug, in addition to their female partner using either an intrauterine device or hormonal contraception and continuing until 4 months following the last dose of study drug. This criterion may be waived for male patients who have had a vasectomy \>6 months before signing the ICF. Exclusion Criteria: 1. History of prior malignancy, except for adequately treated in situ cancer, basal cell, or squamous cell skin cancer, or other cancers (eg, breast, prostate) for which the patient has been disease free for at least 3 years. Prostate cancer patients on active surveillance are eligible. 2. Active brain or leptomeningeal metastasis. Except patients with known brain metastases if they have been treated and MRI shows no evidence of progression for at least 8 weeks and require less than 10 mg/day prednisone/prednisolone or equivalent. 3. Treatment with anti neoplastic therapy ≤ 28 days or ≤ 5× elimination half life, whichever is shorter, before the first dose of study drug. 4. Major surgery requiring general anesthesia ≤ 28 days prior to dosing. 5. History of permanent discontinuation of prior IO therapy due to irAE. 6. Prior treatment targeting ILT2 and/or ILT4 or targeting HLA G. 7. Live or live attenuated vaccine ≤ 28days prior to dosing. 8. Immunosuppressive systemic medication, except topical corticosteroids or systemic corticosteroids at a dose level of ≤ 10 mg/d of prednisone/prednisolone or equivalent. Note: patients with adrenal insufficiency requiring hormonal replacement may receive higher dose of steroids. 9. Prior solid organ or bone marrow transplantation (except cornea transplantation). 10. History of clinically significant cardiovascular events (e.g. DVT ≤ 6 months, PE ≤ 12 months, MI or hospitalization for CHF ≤ 12 months, bleeding disorder or bleeding event ≤ 6 months, current clinically significant arrhythmia or unstable angina pectoris, current uncontrolled history of cerebrovascular accident in the past 6 months, current uncontrolled hypertension).

Contact & Investigator

Central Contact

SparX Biotech

✉ SPX-303@sparxbio.com

📞 847-739-6251

Principal Investigator

Guidong Zhu

STUDY CHAIR

SparX Biotech

Frequently Asked Questions

Who can join the NCT06259552 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Solid Tumor. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06259552 trial and what does that mean for participants?

Phase 1 trials are the first stage of human testing. The primary goal is to assess safety and determine appropriate dosage levels. Participants are closely monitored. These trials typically involve a small number of volunteers.

Is NCT06259552 currently recruiting?

Yes, NCT06259552 is actively recruiting participants. Contact the research team at SPX-303@sparxbio.com for enrollment information.

Where is the NCT06259552 trial being conducted?

This trial is being conducted at Phoenix, United States, Scottsdale, United States, Jacksonville, United States, Rochester, United States.

Who is sponsoring the NCT06259552 clinical trial?

NCT06259552 is sponsored by SparX Biotech(Jiangsu) Co., Ltd.. The principal investigator is Guidong Zhu at SparX Biotech. The trial plans to enroll 232 participants.

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