A Study of FL115 Monotherapy in Unresectable or Metastatic Solid Tumors

NCT07131189 | Active Not Recruiting Phase 1

• 1 other identifier: FL115-102
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 3

Brief Summary

This is a Phase 1, open-label, multicenter clinical study designed to evaluate the safety, tolerability, pharmacokinetics (PK), and preliminary antitumor activity of FL115 administered as monotherapy in subjects with unresectable locally advanced or metastatic solid tumors. The study consists of a dose escalation phase followed by a dose expansion phase to further characterize the safety profile and clinical activity at the recommended dose level.

Conditions

Locally Advanced/Metastatic Solid Tumors

Outcome Measures

Primary Outcomes (3)

• Safety and tolerabilty

  Number of participants with treatment-related adverse events as assessed by CTCAE v5.0

  through study completion, an average of 8months

• MTD

  Maximal Tolerance Dose

  up to 18 months

• RP2D

  Recommended Phase II Dose

  up to 18 months

Study Arms (1)

A Single Arm

EXPERIMENTAL

Drug: FL115

Interventions

FL115 DRUG

FL115 is a novel long-acting IL-15 agonist designed as a fusion protein with a mutated IL-15 structure (IL-15\[N72D\]/IL-15Rα-sFc).

A Single Arm

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Male or female subjects aged 18 years or older and up to 80 years old.
• Subjects with locally advanced or metastatic solid tumors that have been pathologically or cytologically confirmed and have failed all standard treatments, currently have no standard treatment options, or are not suitable for standard treatment.
• With at least one measurable lesion (according to RECIST v1.1).
• ECOG score: 0 - 1.
• Expected survival period ≥ 12 weeks (judged by the investigator).
• Sufficient organ function.
• Voluntary written informed consent and agree to comply with all protocol-specified procedures and follow-up evaluations.
• Fertile subjects (male and female) and their partners agree to use acceptable, investigator-approved contraception during the study-required period.

You may not qualify if:

• If any of the following criteria are met, the subjects will be excluded from the study:
• History of previous anti-tumor treatment:
• Previous use of IL-2 or IL-15 agonists, including but not limited to rhIL-15 (NCI), ALT-803 (ALTOR), NKTR-214 (Nektar).
• Received any anti-tumor investigational or approved drug, biologic, or endocrine immunotherapy (except HRT, oral contraceptives, testosterone, ADT for prostate cancer, or endocrine therapy for breast cancer) within 4 weeks before first dose; or received \>30Gy non-thoracic radiotherapy or within 4 weeks or \>30Gy lung radiotherapy within 8 weeks; or ≤30Gy palliative radiotherapy within 14 days before first dose.
• Within 2 weeks before the first administration of the study drug, received traditional Chinese medicine for anti-tumor indications.
• Subjects who received oral fluoropyrimidines or small-molecule targeted therapies discontinued the treatment ≤2 weeks or 5 half-lives (whichever is longer) prior to the first dose of the study drug.
• Subjects who received mitomycin C or nitrosourea treatment discontinued the medication ≤6 weeks prior to the first dose of the study drug.
• History of other previous treatments and toxicity recovery:
• Known or suspected allergies to FL115 and its excipients; known history of grade 3-4 allergic reactions to interleukin treatment or other fusion proteins.
• Known allergies to indomethacin, acetaminophen, diphenhydramine, ranitidine, cimetidine and/or famotidine.
• Received systemic immunosuppressants within 4 weeks before first dose, except for: ≤10 mg/day prednisone-equivalent, local/inhaled/nasal steroids, ≤7.5 mg/day for adrenal replacement, or one-time use for contrast allergy before imaging.d) .
• Received treatment with granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), thrombopoietic agents (e.g., thrombopoietin \[TPO\], romiplostim, eltrombopag), or erythropoiesis-stimulating agents (e.g., erythropoietin \[EPO\]) within 14 days prior to screening.
• History of allogeneic organ or PBSC/bone marrow transplant.
• Received live viral vaccine within 4 weeks before first dose.
• Prior ≥Grade 3 or treatment-discontinuing irAEs, except for hypothyroidism, type 1 diabetes, or mild skin irAEs (excluding SJS, TEN, or severe dermatitis).

Sponsors & Collaborators

• Suzhou Forlong Biotechnology Co., Ltd: lead

Study Sites (3)

Beijing Cancer Hospital

Beijing, Beijing Municipality, 100142, China

Location

Sun Yat-sen University Cancer Center

Guangzhou, Guangdong, 510000, China

Location

Shandong Cancer Hospital

Jinan, Shandong, 250117, China

Location

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Model Details: Open-label, Multicenter, Dose escalation and Expansion part

Study Record Dates

• First Submitted: July 21, 2025
• First Posted: August 20, 2025
• Study Start: May 30, 2024
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): August 10, 2026
• Last Updated: January 8, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

CN (3)