A Phase 1/2 interventional study of XTX501 in Metastatic NSCLC - Non-Small Cell Lung Cancer and Advanced Solid Tumor, sponsored by Xilio Development, Inc.. Not yet recruiting. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-07-07.
Sponsored by Xilio Development, Inc. · Phase 1/2, Interventional, and Treatment
This is a first-in-human, multicenter, Phase 1/2, open-label study designed to evaluate the safety and tolerability of XTX501 as monotherapy in participants with metastatic non-small cell lung cancer (NSCLC) and select advanced solid tumors.
This is a first-in-human, Phase 1/2, multicenter, open-label study designed to evaluate the safety, tolerability, PK, pharmacodynamics, immunogenicity, and antitumor activity of XTX501, an investigational bispecific PD-1/masked IL-2 in participants with metastatic NSCLC and select advanced solid tumors.
Phase 1, Part 1A will examine XTX501 monotherapy in a Bayesian Optimal Interval design to determine the maximum tolerated dose up to 10 dose regimens.
Phase 1, Part 1B will further evaluate the safety and antitumor activity of XTX501 at dose regimens under consideration for the recommended Phase 2 dose(s).
Phase 2 will further evaluate the efficacy of the selected recommended Phase 2 dose(s).
6,488 studies on the registry are indexed under Carcinoma, Non-Small-Cell Lung; 1,632 are open to participants now.
This study's planned enrollment of 140 is above the median of 62 across 5,213 interventional studies indexed under Carcinoma, Non-Small-Cell Lung.
Browse Carcinoma, Non-Small-Cell Lung studies →Xilio Development, Inc. is the lead sponsor of 4 studies on the registry; 2 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Metastatic NSCLC:
Exclusion Criteria:
In Phase 1, participants with select additional solid tumor types may be enrolled.
Part 1A will examine XTX501 monotherapy in a Bayesian Optimal Interval design to determine the maximum tolerated dose up to 10 dose regimens. Part 1B will further evaluate the safety and antitumor activity of XTX501 at dose regimens under consideration for the recommended Phase 2 dose(s).
Drug: XTX501
Phase 2 will further evaluate the efficacy of the selected recommended Phase 2 dose(s) in participants with metastatic NSCLC.
Drug: XTX501
XTX501 monotherapy
Incidence of Dose Limiting Toxicities (DLTs) in Part 1A
Time frame: Cycle 1 Day 1 up to just prior to the second dose of study drug (approximately 21 days)
Incidence of treatment-emergent adverse events (Phase 1 and Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Incidence of serious adverse events (Phase 1 and Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Incidence of significant change from baseline in clinical laboratory values (Phase 1 and Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Investigator-assessed objective response rate (ORR) per RECIST v1.1 (Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Investigator-assessed objective response rate (ORR) per RECIST v1.1 (Phase 1)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Investigator-assessed duration of response (DOR) per RECIST v1.1 (Phase 1 and Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Investigator-assessed disease control rate (DCR) per RECIST v1.1 (Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Investigator-assessed progression free survival (PFS) per RECIST v1.1 (Phase 2)
Time frame: Up to Safety Follow Up Period (90 [+7] days after the last dose)
Incidence and persistence of antidrug antibodies (ADAs) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Maximum observed plasma concentration (Cmax) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Time of maximum observed concentration (Tmax) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Trough concentrations (Ctrough) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Area under the curve (AUC) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Half-life (t1/2) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Systemic clearance (CL) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
Volume of distribution (Vd) (Phase 1 and Phase 2)
Time frame: Up to End of Treatment (within 10 days of the decision to discontinue XTX501)
No study locations are listed for this record.
Plan to share: No
No publications or documents are linked to this record.
This study is not yet recruiting, as verified in Jun 2026. You cannot join it, but the record below documents what was studied.
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Carcinoma, Non-Small-Cell Lung→
Xilio Development, Inc.