A Phase 1 Study to Evaluate the Safety, Pharmacokinetics, and Preliminary Efficacy of MK-6204 (SKB535) for Injection in Participants With Advanced Solid Tumors

This is an open-label, nonrandomized, multicenter, Phase 1 study to evaluate the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of MK-6204 as monotherapy in participants with advanced solid tumors.

Study Overview

• Status: Recruiting
• Conditions: Advanced Solid Tumors
• Intervention / Treatment: Drug: MK-6204 (SKB535) for Injection

Detailed Description

This is an open-label, nonrandomized, multicenter, Phase 1 study to evaluate the safety, tolerability, pharmacokinetics, and preliminary antitumor activity of MK-6204 as monotherapy in participants with advanced solid tumors. The primary objectives are to evaluate the safety and tolerability of MK-6204. The secondary endpoints include PK parameters, ORR, DOR, and immunogenicity of MK-6204. The study will include a Screening Phase, a Treatment Phase, and a Post-treatment Follow up Phase.

• Study Type: Interventional
• Enrollment (Estimated): 90
• Phase: Phase 1

Contacts and Locations

• Study Contact: Name: Lin Shen; Phone Number: 010-88196561; Email: linshenpku@163.com

Study Locations

• China
  • Beijing, China, 100142
    • Recruiting
    • Beijing Cancer Hospital
    • Principal Investigator: Lin Shen, Dr.
    • Contact: Lin Shen, Dr.
  • Changsha, China, 410031
    • Not yet recruiting
    • Hunan Cancer Hospital
  • Chengdu, China
    • Not yet recruiting
    • West China Hospital of Sichuan University
  • Chongqing, China
    • Not yet recruiting
    • Chongqing University Cancer Hospital
  • Fuzhou, China
    • Not yet recruiting
    • Fujian Provincial Cancer Hospital
  • Shanghai, China
    • Not yet recruiting
    • Shanghai East Hospital
  • Wuhan, China
    • Not yet recruiting
    • Hubei Cancer Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. ≥ 18 years of age
2. Have a histologically or cytologically confirmed advanced/metastatic solid tumor by pathology report and have failed or do not have available standard treatments. The tumor types will be limited to: CRC; Gastric carcinoma or gastroesophageal junction (GEJ) adenocarcinoma; Esophageal carcinoma; Pancreatic cancer; NSCLC; Cervical carcinoma; Head and Neck squamous cell carcinoma.
3. Have measurable disease by RECIST 1.1 as assessed by the local site investigator/radiology. Target lesions situated in a previously irradiated area are considered measurable if progression has been shown in such lesions.
4. Have a performance status of 0 or 1 on the ECOG Performance Scale.
5. The participant has provided documented informed consent for the study.
6. Participants who agree to provide archival tumor tissue sample or newly obtained core, incisional, or excisional biopsy of a tumor lesion not previously irradiated.
7. Participants who have AEs due to previous anticancer therapies must have recovered to ≤Grade 1 or baseline. Participants with endocrine-related AEs who are adequately treated with hormone replacement or participants who have ≤Grade 2 neuropathy are eligible.

Exclusion Criteria:

1. Active severe digestive disease, including but not limited to complete or incomplete gastric outlet obstruction, persistent/recurrent vomiting, severe gastrointestinal hemorrhage, gastric or duodenal ulcers, acute gastrointestinal perforation, acute necrotizing pancreatitis, ulcerative enteritis, congenital megacolon, or Crohn's disease.
2. Participants with a history of interstitial lung disease (ILD) or a history of noninfectious pneumonitis that required steroids, have current ILD/pneumonitis, or where suspected ILD/pneumonitis cannot be ruled out by imaging at screening.
3. Received strong cytochrome P450 (CYP3A4) inhibitors or inducers within 2 weeks prior to the first dose of study intervention or within 5 half-lives of drug elimination, whichever is longer.
4. Received strong breast cancer resistance protein (BCRP) inhibitors within 2 weeks prior to the first dose of study intervention or within 5 half-lives of drug elimination, whichever is longer.
5. Received prior systemic anticancer therapy including investigational agents within 4 weeks or 5 half-lives, whichever is shorter, before intervention allocation.
6. Known additional malignancy that is progressing or has required active treatment within the past 2 years.
7. Known active CNS metastases and/or carcinomatous meningitis. Participants with previously treated brain metastases may participate provided they are radiologically stable (i.e., without evidence of progression) for at least 4 weeks as confirmed by repeat imaging performed during the study screening, are clinically stable and have not required steroid treatment for at least 14 days before the first dose of study intervention.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: MK-6204 (SKB535) for Injection; Several dose levels of MK-6204 (SKB535) for Injection are planned and administered every 3 weeks.	Drug: MK-6204 (SKB535) for Injection; MK-6204 (SKB535) for injection is administered every 3 weeks (q3w) until radiographic disease progression (PD), intolerable toxicity, death, or discontinuation of treatment, whichever occurs first.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Dose Limiting Toxicities (DLT)	DLT is defined as an adverse event (AE) that meets protocol defined DLT criteria during the evaluation period and is at least possibly related to study drug.	From the date of first dose until up to 21 days of intervention
Adverse Event (AE)	An AE is defined as any untoward medical occurrence in a clinical study participant, temporally associated with the use of study intervention, whether considered related to the study intervention.	From the date of first dose until up to 30 days after the last dose of intervention
Serious Adverse Event (SAE)	An SAE is defined as any serious untoward medical occurrence that meets the pre-specified criteria in the protocol	From the date of first dose until up to 30 days after the last dose of intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
PK parameter AUC	PK parameter AUC after single and multiple doses	Through study completion, an average of 2 years
PK parameter Cmax	PK parameter Cmax after single and multiple doses	Through study completion, an average of 2 years
PK parameter Cmin	PK parameter Cmin after single and multiple doses	Through study completion, an average of 2 years
Objective response rate (ORR)	ORR refers to the proportion of participants who have achieved confirmed complete response (CR) or partial response (PR).	Through study completion, an average of 2 years
Duration of response (DOR)	DOR refers to the time from the first documented evidence of CR or PR until disease progression or death due to any cause, whichever occurs first.	Through study completion, an average of 2 years
Immunogenicity of MK-6204	ADA incidence	Through study completion, an average of 2 years

Collaborators and Investigators

• Sponsor: Sichuan Kelun-Biotech Biopharmaceutical Co., Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): December 12, 2024
• Primary Completion (Estimated): December 31, 2029
• Study Completion (Estimated): December 31, 2029

Study Registration Dates

• First Submitted: December 2, 2024
• First Submitted That Met QC Criteria: December 5, 2024
• First Posted (Actual): December 10, 2024

Study Record Updates

• Last Update Posted (Actual): May 7, 2026
• Last Update Submitted That Met QC Criteria: May 5, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: tolerability; safety; pharmacokinetics; ADC
• Additional Relevant MeSH Terms: Neoplasms; Amino Acids, Peptides, and Proteins; Proteins; Enzymes; Enzymes and Coenzymes; Oxidoreductases; Tumor Suppressor Proteins; Neoplasm Proteins; Short Chain Dehydrogenase-Reductases; NAD (+) and NADP (+) Dependent Alcohol Oxidoreductases; Alcohol Oxidoreductases; WW Domain-Containing Oxidoreductase
• Other Study ID Numbers: MK-6204-001/SKB535-I-01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No