A Study of ZN-c3 in Combination With Gemcitabine in Subjects With Osteosarcoma
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT04833582 |
Recruitment Status :
Recruiting
First Posted : April 6, 2021
Last Update Posted : February 1, 2023
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Osteosarcoma | Drug: ZN-c3 Drug: Gemcitabine | Phase 1 Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 84 participants |
Allocation: | N/A |
Intervention Model: | Sequential Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1/2 Dose Escalation and Dose Expansion Study of ZN-c3 in Combination With Gemcitabine in Adult and Pediatric Subjects With Relapsed or Refractory Osteosarcoma |
Actual Study Start Date : | August 1, 2021 |
Estimated Primary Completion Date : | August 30, 2023 |
Estimated Study Completion Date : | December 30, 2023 |

Arm | Intervention/treatment |
---|---|
Experimental: Combination ZN-c3 with Gemcitabine |
Drug: ZN-c3
ZN-c3 is an investigational drug. Drug: Gemcitabine Gemcitabine is an approved drug
Other Name: Gemzar |
- Incidence of dose-limiting toxicities (DLT) in DLT evaluable subjects and the incidence and severity of adverse events. [ Time Frame: Through Cycle 1 (21 days) Phase 1 ]
- Event-free survival (EFS) at 18 weeks per RECIST (Response Evaluation Criteria in Solid Tumors) Guideline version 1.1. [ Time Frame: During phase 2, at 18 weeks ]EFS at 18 weeks is defined as time from study enrollment until date of disease progression, or detection of disease at a previously uninvolved site, or date of death of the subjects at 18 weeks.
- Event-free survival (EFS) per RECIST Guideline version 1.1. [ Time Frame: At 12 months ]EFS is defined as time from study enrollment until date of last contact, date of disease progression, or detection of disease at a previously uninvolved site, or date of death.
- Median overall survival (OS) and OS at 12 months per RECIST Guideline version 1.1. [ Time Frame: At 12 months ]OS is defined as the time from date of first dosing until the date of death.
- The frequency and severity of adverse events (AEs) and laboratory abnormalities per the National Cancer Institute Common Terminology (NCI CTCAE) version 5.0.lities. [ Time Frame: Through completion, approximately 42 months ]
- Plasma pharmacokinetics (PK) maximum concentration (Cmax). [ Time Frame: Through completion, approximately 42 months ]
- Plasma PK time to maximum concentration (Tmax). [ Time Frame: Through completion, approximately 42 months ]
- Area under the plasma concentration versus timepoint curve (AUC last). [ Time Frame: Through completion, approximately 42 months ]
- Terminal half-life of the plasma PK concentration. [ Time Frame: Through completion, approximately 42 months ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 12 Years and older (Child, Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Age ≥ 12 years at the time of informed consent
- Bodyweight ≥ 40 kg
- Histologically documented relapsed or metastatic osteosarcoma.
- Must have measurable disease according to RECIST Guideline version 1.1 criteria.
- Adequate hematologic and organ function.
- Female subjects of childbearing potential and male subjects must agree to use an effective method of contraception per institutional standard prior to the first dose and for 6 months after study treatment discontinuation.
- Willingness and ability to comply with scheduled visits, treatment plan, laboratory tests, and other study procedures.
Exclusion Criteria:
- Unresolved toxicity of Grade >1 attributed to prior therapies (excluding: Grade ≤2 neuropathy, alopecia, or skin pigmentation)
- Prior therapy with a WEE1 inhibitor
- A serious illness or medical condition(s).
- Pregnant or lactating females. Females of childbearing potential with a positive serum pregnancy test <14 days to Day 1.
- Subjects with active (uncontrolled, metastatic) second malignancies or requiring therapy.
- 12-lead ECG demonstrating a corrected QT interval using Fridericia's formula (QTcF) of >470 ms, except for subjects with atrioventricular pacemakers or other conditions (e.g., right bundle branch block) that render the QT measurement invalid.
- History or current evidence of congenital or family history of long QT syndrome or Torsades de Pointes (TdP).
- Taking medications with a known risk of TdP.
- Administration of strong and moderate CYP3A4 inhibitors/inducers and strong and moderate P-gp inhibitors.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT04833582
Contact: Project Director | (858) 263-4333 | medicalaffairs@zentalis.com |
United States, California | |
Site 0106 | Recruiting |
Los Angeles, California, United States, 90095 | |
Site 0124 | Not yet recruiting |
Oakland, California, United States, 94609 | |
Site 0195 | Recruiting |
Santa Monica, California, United States, 90403 | |
United States, New York | |
Site 0105 | Recruiting |
New York, New York, United States, 10065 | |
United States, Ohio | |
Site 0107 | Recruiting |
Cincinnati, Ohio, United States, 45229 | |
United States, Oregon | |
Site 0123 | Not yet recruiting |
Portland, Oregon, United States, 97239 | |
United States, Tennessee | |
Site 0193 | Not yet recruiting |
Memphis, Tennessee, United States, 38105 | |
Site 0197 | Not yet recruiting |
Nashville, Tennessee, United States, 37332 | |
United States, Texas | |
Site 0103 | Recruiting |
Houston, Texas, United States, 77030 | |
United States, Virginia | |
Site 0188 | Recruiting |
Richmond, Virginia, United States, 23298 | |
United States, Washington | |
Site 0122 | Recruiting |
Seattle, Washington, United States, 98195 | |
France | |
Site 3604 | Recruiting |
Bordeaux, France, 33000 | |
Site 3601 | Not yet recruiting |
Lyon, France, 69008 | |
Site 3602 | Not yet recruiting |
Marseille, France, 13385 | |
Site 3606 | Not yet recruiting |
Paris, France, 75248 | |
Site 3605 | Recruiting |
Toulouse, France, 31100 |
Responsible Party: | K-Group, Beta, Inc., a wholly owned subsidiary of Zentalis Pharmaceuticals, Inc |
ClinicalTrials.gov Identifier: | NCT04833582 |
Other Study ID Numbers: |
ZN-c3-003 |
First Posted: | April 6, 2021 Key Record Dates |
Last Update Posted: | February 1, 2023 |
Last Verified: | January 2023 |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Osteosarcoma Neoplasms, Bone Tissue Neoplasms, Connective Tissue Neoplasms, Connective and Soft Tissue Neoplasms by Histologic Type Neoplasms Sarcoma Gemcitabine Antimetabolites, Antineoplastic |
Antimetabolites Molecular Mechanisms of Pharmacological Action Antineoplastic Agents Antiviral Agents Anti-Infective Agents Enzyme Inhibitors Immunosuppressive Agents Immunologic Factors Physiological Effects of Drugs |