A Vaccine Booster (GEO-CM04S1) for the Prevention of COVID-19 in Patients With Chronic Lymphocytic Leukemia
This phase II trial compares the effect of the GEO-CM04S1 vaccine with the current standard of care vaccine in preventing COVID-19 infections in patients with chronic lymphocytic leukemia (CLL). The GEO-CM04S1 vaccine uses a modified vaccinia virus (MVA) backbone that may be more effective at boosting COVID-19 immunity in patients with poor immune responses. MVA strongly induces T cell expansion (infection fighting blood cells) even in the background of a suppressed immune system, which is the case in the targeted CLL patient population. Using the GEO-CM04S1 vaccine may be more effective at preventing COVID-19 infection in patients diagnosed with CLL.
Ask AI to explain this studyKey things to know
This describes the study’s primary purpose.
Plus 1 other study approaches.
These are broad labels—not an eligibility decision.
Checked against the public recordLast updated Sep 9, 2026 · Source: ClinicalTrials.gov
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Interventional
Locations may change over time.
Study sponsor
What this study is about
- Purpose
- Prevention
- Study type
- Interventional
- Phase
- Phase 2
- Sponsor
- City of Hope Medical Center
- Interventions being studied
- Procedure: Biospecimen Collection; Biological: mRNA COVID-19 Vaccine; Biological: Synthetic MVA-based SARS-CoV-2 Vaccine COH04S1
How this study is categorized
These labels come from structured fields and exact terms in the public record.
Who may be able to participate
The sponsor separates these requirements into two groups. You do not need to interpret them alone—use them to guide a conversation with the study team.
- Documented informed consent of the participant and/or legally authorized representative
- Age: \>= 18 years
- Eastern Cooperative Oncology Group (ECOG) =\< 1
- Histologically confirmed diagnosis of CLL according to World Health Organization (WHO) classification
- Prior COVID-19 Vaccination (2 or more Pfizer or Moderna) with last injection \>= 3 months prior
- Fully recovered from the acute toxic effects (except alopecia) to =\< Grade 1 to prior anti-cancer therapy
- White Blood Cells (WBC) \>= 1,000/mm\^3 (To be performed within 14 days prior to Day 1 of protocol therapy)
- Platelets \>= 50,000/mm\^3 (To be performed within 14 days prior to Day 1 of protocol therapy)
- Total bilirubin =\< 1.5 X upper limit of normal (ULN) (unless has Gilbert's disease) (To be performed within 14 days prior to Day 1 of protocol therapy)
- Aspartate aminotransferase (AST) =\< 2.5 x ULN (To be performed within 14 days prior to Day 1 of protocol therapy)
- Alanine transaminase (ALT) =\< 2.5 x ULN (To be performed within 14 days prior to Day 1 of protocol therapy)
- Creatinine clearance \<1.5 ULN (To be performed within 14 days prior to Day 1 of protocol therapy)
- Women of childbearing potential (WOCBP): negative urine or serum pregnancy test (To be performed within 14 days prior to Day 1 of protocol therapy)
- If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required
- Agreement by females and males of childbearing potential to use an effective method of birth control or abstain from heterosexual activity for the course of the study through at least 6 weeks after the last vaccine injection
- Childbearing potential defined as not being surgically sterilized (men and women) or have not been free from menses for \> 1 year (women only)
- Known current SARS CoV-2 infection
- Prior Evusheld or other anti-SARS CoV-2 prophylaxis \< 2 weeks prior
- Prior hematopoietic cell transplantation (HCT) or chimeric antigen receptor (CAR) T cell therapy within the previous year
- Systemic corticosteroids required for chronic conditions at doses \> 0.5mg/kg/day prednisone equivalent within 7 days of enrollment
- Intensive cytotoxic therapies, T-cell depleting therapies, within 30 days of enrollment; however, patients with stable disease on maintenance therapies are allowed (See ConMeds for lists of acceptable and contraindicated therapies)
- Participants who have had a live vaccine =\< 30 days prior to administration of any dose of study vaccine or subjects who are =\< 2 weeks within administration of inactivated vaccines (e.g., influenza vaccine). Flu shots are allowed \> 2 weeks before a study vaccine injection and \> 2 weeks post study vaccine injection
- History of allergic reactions attributed to compounds of similar chemical or biologic composition to study agent (e.g., egg allergies)
- Active infection not controlled on appropriate therapy
- History of adverse event with a prior smallpox vaccination
- History of pericarditis or myocarditis
- Any MVA vaccine or poxvirus vaccine in the last 12 months
- Females only: Pregnant or breastfeeding
- Any other condition that would, in the Investigator's judgment, contraindicate the patient's participation in the clinical study due to safety concerns with clinical study procedures
- Prospective participants who, in the opinion of the investigator, may not be able to comply with all study procedures (including compliance issues related to feasibility/logistics)
Important: This is the sponsor’s public criteria, not a determination of eligibility. The study team must review your individual situation.
U.S. locations
- City of Hope Medical CenterDuarte, California
Source and freshness
Processed from ClinicalTrials.gov. Last public update: Sep 9, 2026. Always confirm current availability with the study team.