A Study to Evaluate the Efficacy of Cemsidomide + Dexamethasone in Participants With Relapsed/Refractory Multiple Myeloma (MOMENTUM)

A Phase 2, Open-Label, Single-Arm, Multicenter Study to Evaluate the Efficacy of Cemsidomide + Dexamethasone in Subjects With Relapsed/Refractory Multiple Myeloma

This is a Phase 2, open-label, single-arm, multicenter study to assess the antimyeloma activity and further characterize the safety, tolerability, PK, and PD of cemsidomide in combination with dexamethasone in participants with relapsed/refractory multiple myeloma (r/r MM).

Study Overview

• Status: Recruiting
• Conditions: Multiple Myeloma; Relapsed/Refractory Multiple Myeloma
• Intervention / Treatment: Drug: Cemsidomide; Drug: Dexamethasone

• Study Type: Interventional
• Enrollment (Estimated): 100
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Study Medical Officer; Phone Number: (617) 231-0700; Email: clinicaltrials@c4therapeutics.com

Study Locations

• United States
  • California
    • West Hollywood, California, United States, 90069
      • Recruiting
      • Berenson Cancer Center
      • Contact: James Berenson, MD
  • Michigan
    • Grand Rapids, Michigan, United States, 49546
      • Recruiting
      • START Midwest
      • Contact: Andrew Sochacki, MD
  • Texas
    • San Antonio, Texas, United States, 78229
      • Recruiting
      • START San Antonio
      • Contact: Kyriakos Papadopoulos, MD

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Be willing and able to provide signed informed consent for the study.
2. Age ≥ 18 years at the time of signed consent.
3. Subjects must have a documented diagnosis of MM and measurable disease at enrollment.
4. Received at least 3 prior anti-myeloma regimens (for a minimum of 2 or more consecutive cycles) that must have included an immunomodulatory drug (i.e., IKZF 1/3 degrader), a proteasome inhibitor, an anti-CD38 antibody, and a T-cell engager (TCE) or chimeric antigen receptor T-cell (CAR-T) therapy, unless not available per local standard of care.
5. Subjects need to have adequate organ function.
6. Toxicities from prior anticancer therapies must have resolved to baseline severity or CTCAE ≤ Grade 1.
7. Female subjects may not be pregnant or intend to become pregnant, may not breastfeed or intend to breastfeed, or donate ova during their participation in this study until 30 days after the last dose of study treatment.
8. Male subjects must agree to use a condom when having intercourse with a person of childbearing potential during the Treatment Period and for at least 30 days after the last dose of study treatment.
9. Male subjects must refrain from donating sperm during the Treatment Period and for 30 days after discontinuation.
10. Subjects must refrain from donating blood during study treatment and for 30 days after discontinuation.

Exclusion Criteria:

1. Presence of myeloma in the central nervous system (CNS).

2. Subjects with any of the following:

   • Systemic light chain amyloidosis
   • Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal gammopathy, and Skin changes (POEMS) Syndrome
   • Myelodysplastic syndrome (MDS).
3. Previously treated with cemsidomide.
4. Clinically significant impaired cardiac function or cardiac disease.
5. Thromboembolic event within 3 months prior to enrollment.
6. Known malignancy other than study indication that has progressed or required treatment within the past 3 years.
7. Uncontrolled active bacterial, fungal, or viral infection.
8. Inability or difficulty swallowing tablets.

NOTE: Other inclusion/exclusion criteria may apply, per protocol.

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: Cemsidomide + Dexamethasone: Participants receive cemsidomide plus dexamethasone during a 28-day treatment cycle, and will continue to receive treatment until the participant meets one of the discontinuation criteria.	Drug: Cemsidomide; dosed orally (PO) once a day (QD) 14 days on/14 days off for each 28-day cycle; Drug: Dexamethasone; dosed PO once a week (QW) on Days 1, 8, 15, and 22 for each 28-day cycle

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Overall response rate (ORR) per International Myeloma Working Group (IMWG) Response Criteria by an Independent Review Committee (IRC)	up to approximately 43 months

Secondary Outcome Measures

Outcome Measure	Time Frame
Duration of response (DoR; IRC assessed)	up to approximately 43 months
Complete response (CR) rate (IRC assessed)	up to approximately 43 months
Time to response (IRC assessed)	up to approximately 43 months
Progression free survival (PFS; IRC assessed)	up to approximately 43 months
Overall survival (OS)	up to approximately 43 months
Adverse events (AEs); serious AEs (SAEs); AEs leading to treatment interruption, reduction, or discontinuation; and deaths	within 30 to 35 days of the last dose of study treatment
Plasma concentrations of cemsidomide	up to approximately 4 months

Collaborators and Investigators

• Sponsor: C4 Therapeutics, Inc.
• Investigators: Principal Investigator: Binod Dhakal, M.D., Medical College of Wisconsin; Principal Investigator: Martin Kaiser, M.D., The Royal Marsden; Principal Investigator: Aurore Perrot, M.D., Universite de Toulouse

Study record dates

Study Major Dates

• Study Start (Actual): February 18, 2026
• Primary Completion (Estimated): March 1, 2030
• Study Completion (Estimated): March 1, 2030

Study Registration Dates

• First Submitted: December 9, 2025
• First Submitted That Met QC Criteria: December 9, 2025
• First Posted (Actual): December 16, 2025

Study Record Updates

• Last Update Posted (Actual): March 12, 2026
• Last Update Submitted That Met QC Criteria: March 10, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: Multiple Myeloma; dexamethasone; cemsidomide
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Neoplasms; Immune System Diseases; Neoplasms by Histologic Type; Hematologic Diseases; Lymphoproliferative Disorders; Immunoproliferative Disorders; Neoplasms, Plasma Cell; Hemostatic Disorders; Paraproteinemias; Blood Protein Disorders; Hemorrhagic Disorders; Hemic and Lymphatic Diseases; Multiple Myeloma; Polycyclic Compounds; Pregnadienes; Pregnanes; Steroids; Fused-Ring Compounds; Steroids, Fluorinated; Pregnadienetriols; Dexamethasone
• Other Study ID Numbers: CFT7455-2101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No