To Evaluate the Safety, Tolerability, Pharmacokinetics and Antitumor Activity of DAY301 in Participants With Locally Advanced or Metastatic Solid Tumors

Phase 1

Recruiting

• Conditions: Advanced or Metastatic Solid Tumors
• Interventions: Drug: DAY301

• Registration Number: NCT06752681
• Lead Sponsor: Day One Biopharmaceuticals, Inc.

Brief Summary

This is a Phase 1a/1b, open-label, dose escalation and expansion study to evaluate the safety and anti-tumor activity of DAY301, a PTK7-directed antibody-drug conjugate in participants with advanced or metastatic solid tumors. The study comprises of 2 phases: Phase 1a dose escalation where participants will be administered DAY301 at escalating dose levels to assess safety and tolerability, and to determine the maximum tolerated dose (MTD) and/or the recommended dose (RD); In Phase 1b dose expansion, DAY301 will be evaluated in dose expansion cohorts.

Detailed Description

Not available

Study Timeline

• Study Start: 2024-11-18
• Study First Submitted: 2024-12-23
• Study First Submitted QC: 2024-12-23
• Study First Posted: 2024-12-31
• Status Verified: 2025-10
• Last Update Submitted: 2025-10-08
• Last Update Posted: 2025-10-10
• Primary Completion: 2027-12
• Study Completion: 2028-12-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 254

Inclusion Criteria

• Histologically or cytologically confirmed diagnosis of advanced or metastatic solid tumors of the following histologies:
• Ovarian cancer
• Esophageal squamous cell carcinoma
• Triple-negative breast cancer
• Non-small cell lung cancer
• Small cell lung cancer
• Head and neck squamous cell carcinoma
• Gastric/gastroesophageal junction adenocarcinoma
• Cervical squamous cell carcinoma
• Endometrial cancers

(Participants must have been previously treated with standard of care systemic therapy, or for whom no standard therapy is available).

• Availability of tumor tissue sample (either an archival specimen or a fresh biopsy) at screening
• Measurable disease per Response Evaluation Criteria in Solid Tumors, Version 1.1 (RECIST v1.1).
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
• Adequate organ function.

Exclusion Criteria

• Prior use of PTK7 targeting treatment (Phase 1a) or prior use of PTK7 targeting treatments and/or topoisomerase 1 (TOP1) inhibitor-based antibody-drug conjugate (ADC) (Phase 1b).

• Phase 1b disease-specific exclusion criteria:

  1. Cohort 1: Neuroendocrine tumors or endometrial sarcoma (eg, stromal sarcoma, leiomyosarcoma, or other types of pure sarcomas)
  2. Cohort 2: Ovarian cancer that progressed >6 months after the last dose of platinum-based chemotherapy (platinum-sensitive disease), or disease that did not respond (partial response [PR] or complete response [CR]) to or progressed ≤91 days after the last dose of first-line platinum-based chemotherapy (primary platinum-refractory disease)
  3. Cohort 3: nasopharyngeal primary tumors.

• History of small bowel obstruction requiring hospitalization within 3 months prior to the first dose of study treatment.

• Ascites requiring frequent paracentesis (more often than approximately every 4 weeks) for symptomatic management, or new onset within 4 weeks prior to the first dose of study treatment. Patients with an indwelling catheter may be considered eligible, after consultation with the medical monitor.

• Active or progressing brain metastases or evidence of leptomeningeal disease.

• Persistent toxicities from previous systemic antineoplastic treatments of Grade >1, excluding alopecia and vitiligo.

• Systemic antineoplastic therapy within five half-lives or 4 weeks, whichever is shorter, prior to first dose of study treatment, including investigational agents.

Note: Other protocol defined Inclusion/Exclusion criteria may apply.

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
DAY301 intravenous (IV) infusion	DAY301	DAY301 will be administered at different dose levels in dose escalation and at the RD in dose expansion cohorts.

Primary Outcome Measures

Name	Time	Method
Phase 1a: Dose Escalation: Number of participants with reported Dose Limiting Toxicities (DLTs)	Within 21 days of first infusion (Day 1)	To evaluate adverse events (AEs) considered dose limiting toxicities that occur in the first cycle of treatment (within a DLT observation period).
Phase 1a: Dose Escalation: Number of participants with reported adverse events (AEs) or serious AEs (SAEs)	through the duration of treatment, up to approximately 12 months	The type, incidence, and severity of AEs and SAEs will be determined using the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE) v5.0.
Phase 1a: Dose Escalation: Frequency of dose interruptions	through the duration of treatment, up to approximately 12 months	The frequency at which dose interruptions occur during dose-escalation
Phase 1a: Dose Escalation: Duration of dose interruptions	through the duration of treatment, up to approximately 12 months	The duration of dose interruptions that occur during dose-escalation.
Phase 1a: Dose Escalation: Frequency of dose reductions	through the duration of treatment, up to approximately 12 months	The frequency at which dose reductions occur during dose-escalation.
Phase 1a: Dose Escalation: Duration of dose reductions	through the duration of treatment, up to approximately 12 months	The duration of dose reductions that occur during dose-escalation.
Phase 1b: Dose Expansion: Objective response rate	through the duration of treatment, up to approximately 12 months-up	Objective response rate based on best overall response (BOR) will be assessed by investigators according to Response Evaluation Criteria in Solid Tumors (RECIST v1.1).
Phase 1b: Dose Expansion: Number of participants reporting AEs and SAEs	through the duration of treatment, up to approximately 12 months	The type, incidence, and severity of AEs and SAEs will be determined using the NCI CTCAE v5.0.
Phase 1b: Dose Expansion: Frequency of dose interruptions	through the duration of treatment, up to approximately 12 months	The frequency at which dose interruptions occur during dose-expansion.
Phase 1b: Dose Expansion: Duration of dose interruption	through the duration of treatment, up to approximately 12 months	The duration of dose interruptions that occur during dose-expansion.
Phase 1b: Dose Expansion: Frequency of dose reductions	through the duration of treatment, up to approximately 12 months	The frequency at which dose reductions occur during dose-expansion.
Phase 1b: Dose Expansion: Duration of dose reductions	through the duration of treatment, up to approximately 12 months	The duration of dose reductions that occur during dose-expansion.

Secondary Outcome Measures

Name	Time	Method
Phase 1a and Phase 1b: Maximum concentration (Cmax) of DAY301	Varying timepoints through the duration of treatment, up to approximately 12 months	Blood samples will be collected at indicated time points for the analysis of pharmacokinetic parameters.
Phase 1a and Phase 1b: time to Cmax (Tmax) of DAY301	Varying timepoints through the duration of treatment, up to approximately 12 months	Blood samples will be collected at indicated time points for the analysis of pharmacokinetic parameters.
Phase 1a and Phase 1b: area under the curve (AUC) of DAY301	Varying timepoints through the duration of treatment, up to approximately 12 months	Blood samples will be collected at indicated time points for the analysis of pharmacokinetic parameters.
Phase 1a and Phase 1b: terminal half-life (t1/2) of DAY301	Varying timepoints through the duration of treatment, up to approximately 12 months	Blood samples will be collected at indicated time points for the analysis of pharmacokinetic parameters.
Phase 1a Dose Escalation: Objective response rate	through the duration of treatment, up to approximately 12 months	Objective response rate based on BOR will be assessed by investigators according to RECIST v1.1.
Phase 1a and 1b: Clinical Benefit rate (CBR)	through the duration of treatment, up to approximately 12 months	Clinical Benefit rate will be assessed by investigators according to RECIST v1.1.
Phase 1a and 1b: duration of response (DOR)	through the duration of treatment, up to approximately 12 months	Duration of response will be assessed by investigators according to RECIST v1.1.
Phase 1a and 1b: time to response (TTR)	through the duration of treatment, up to approximately 12 months	Time to response will be assessed by investigators according to RECIST v1.1.
Phase 1a and 1b: Progression-free survival	through the duration of treatment, up to approximately 12 months	Progression-free survival will be assessed by investigators according to RECIST v1.1.
Phase 1b: Overall survival	through the duration of treatment, up to approximately 12 months	Overall survival will be assessed by investigators.
Phase 1a and 1b: Number of participants with positive antidrug antibodies (ADAs)	varying timepoints through the duration of treatment, up to approximately 12 months	Assessed by the measure of anti-drug antibodies in serum.

Trial Locations

Locations (12)

Site: 001-058; 🇺🇸 New Haven, Connecticut, United States

Site: 001-063; 🇺🇸 Lake Mary, Florida, United States

Site: 001-064; 🇺🇸 Sarasota, Florida, United States

Site: 001-039; 🇺🇸 New York, New York, United States

Site: 001-073; 🇺🇸 Oklahoma City, Oklahoma, United States

Site: 001-065; 🇺🇸 Nashville, Tennessee, United States

Site: 001-069; 🇺🇸 Houston, Texas, United States

Site: 011-013; 🇨🇦 Vancouver, British Columbia, Canada

Site: 011-005; 🇨🇦 Toronto, Ontario, Canada

Site: 001-060; 🇺🇸 Indianapolis, Indiana, United States

Scroll for more (2 remaining)