AzTrials
AzTrials

COVID-19Phase 1/2CONTENDERNCT06810934

A Phase 1/2A, Randomized Study of a T Follicular Helper (TFH)-Targeting Genetic Vaccine Strategy Designed to Induce Broad, Durable Immune Responses

A Phase 1/2 study testing CoTend-BXBB (SARS2-30404) and CoTend-s3BXBB (SARS2-17032) in people with COVID-19 and SARS-CoV-2 Infection, run by Kara Chew at 2 sites in United States.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
Search all trials

Trial summary

The goal of this clinical trial is to test two investigational COVID-19 booster vaccines, called CoTend-s3BXBB and CoTend-BXBB, in healthy volunteers ages 40-64. The CoTend-s3BXBB vaccine includes a component called "s3", which was designed to improve the body's response to the vaccine. Read more about this study

Who is it for?
Ages 40 to 64 yearsHealthy volunteers can take part
Conditions the study is for
COVID-19, SARS-CoV-2 Infection
What is being tested?
CoTend-BXBB (SARS2-30404) and CoTend-s3BXBB (SARS2-17032)
Could I receive a placebo?
Yes, some participants may receive a placebo
How many people
80 participants
Where
2 sitesUnited States
Study dates
21 Oct 2025to Oct 2029
Phase
Phase 1/2
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 40 to 64 years
  • All sexes
  • Healthy volunteers accepted
  • Adult

Who may be able to join

  • Individuals 40 - 64 years of age
  • Received at least two doses of a COVID-19 mRNA vaccine (Moderna or Pfizer) > 120 days before study entry
  • Nasal SARS-CoV-2 negative by molecular (polymerase chain reaction, PCR) testing at screening
  • The following laboratory criteria must be met at screening:
  • Total white blood cell (WBC) count > 3500 cells/mm3
  • Absolute neutrophil count (ANC) > 1500 cells/mm3
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  • Hemoglobin > 13.5 g/dL if male sex and > 12.0 g/dL if female sex
  • Platelet count > 140,000/uL
  • Estimated creatinine clearance (CrCl) > 50 mL/min by Cockroft-Gault equation
  • Total bilirubin ≤ 1.1x upper limit of normal (ULN)
  • Aspartate aminotransferase (AST) ≤ 1.3x ULN
  • Alanine aminotransferase (ALT) ≤ 1.3x ULN
  • Individuals of reproductive potential must have a negative serum or urine beta-human chorionic gonadotropin (ß-HCG) test at screening and within 48 hours prior to entry.
  • Reproductive potential is defined as:
  • Participants who have reached menarche
  • Participants who have not been post-menopausal for at least 12 consecutive months with follicle-stimulating hormone (FSH) ≥40 IU/mL or 24 consecutive months if an FSH is not available
  • Participants who have not undergone surgical contraception (e.g., hysterectomy, bilateral oophorectomy, bilateral tubal ligation, or bilateral salpingectomy) NOTE: Participants who have undergone bilateral tubal ligation within the 24 weeks prior to screening are considered to be of reproductive potential and, if participating in sexual activity that could lead to pregnancy, contraception is required as per 5.2.2 exclusion criterion 2.
  • Able and willing to provide informed consent

Who cannot join

  • Participants are excluded from the study if any of the following criteria are met:
  • Pregnant or breastfeeding
  • For participants capable of becoming pregnant and engaging in sexual activity that can lead to pregnancy, unwillingness to use contraception during participation in the study. For participants capable of becoming pregnant, two of the following forms of contraception are required through 30 days following administration of study intervention, one of which must be a barrier method:
  • Condoms (male or female) with or without a spermicidal agent
  • Diaphragm or cervical cap with spermicide
  • Intrauterine device (IUD)
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  • Hormone-based contraceptive such as oral birth control pills
  • Known close contact with anyone with confirmed SARS-CoV-2 infection (defined as positive SARS-CoV-2 nucleic acid or antigen testing by laboratory-based or home self-test) within 2 weeks prior to expected study entry
  • Plan to receive a non-study SARS-CoV-2 vaccine within 8 weeks after study entry
  • HIV infection
  • Hepatitis B core antibody or hepatitis B surface antigen positive at screening
  • Current active hepatitis C. Participants must be hepatitis C virus (HCV) antibody negative or have evidence of cleared HCV infection. If the participant is HCV antibody positive or indeterminate, an unquantifiable HCV RNA result (below lower limit of quantification, either target detected or target not detected) within 42 days prior to study entry is required. Those who are currently receiving HCV antiviral therapy or those who have received HCV treatment in the last 3 months prior to study entry will be excluded.
  • History of cirrhotic liver disease
  • History of thrombosis with thrombocytopenia syndrome (TTS), immune thrombocytopenia, thromboembolic events, capillary leak syndrome, other thrombotic disease or known increased risk of thrombosis due to genetic disorders or malignancy
  • History of or active autoimmune disease that has required systemic immunosuppressive or immunomodulatory therapy
  • History of myocarditis, pericarditis, or myopericarditis
  • Potential myocarditis or pericarditis identified at screening, defined as high-sensitivity troponin I (hsTnI) \> ULN or 12-lead ECG compatible with pericarditis WITH compatible symptoms (regardless of troponin I level) at screening
  • History of Guillain-Barré syndrome
  • History of coagulopathy or bleeding disorder considered a contraindication to intramuscular injection or phlebotomy
  • Symptomatic acute or chronic illness requiring ongoing medical or surgical care, including requirement for new medications, in the past 3 months. Transient illnesses or injuries that are resolved prior to screening are not exclusionary. Minor adjustments in stable therapy for chronic conditions such as hypertension are not exclusionary. Use of over-the-counter medications for any acute or chronic illness is also not exclusionary.
  • Serious medical or psychiatric illness that, in the opinion of the site investigator, would interfere with the ability to adhere to study requirements or to give informed consent
  • Treatment with systemic immunosuppressive or immunomodulatory drugs, and/or exposure to any immunosuppressive/immunomodulatory drug in the 30 days prior to study entry (e.g. corticosteroid therapy equal to or exceeding a dose of 20 mg/day of prednisone for more than 10 days, interleukins, interferons, methotrexate, rituximab, and cancer chemotherapy). Use of topical, inhaled, intra-articular, or nasal steroid use is not exclusionary.
  • Active malignancy or history of malignancy within the 4 years prior to study entry. Non-melanoma skin cancers (such as basal or squamous cell skin cancers) and non-invasive cervical or anal intraepithelial lesions are not exclusionary.
  • History of solid organ or hematopoietic stem cell transplantation
  • History of primary immunodeficiency disorder
  • Ongoing complications or morbidity associated with prior diagnoses of malignancies requiring continued medical or surgical intervention. Chronic stable complications or morbidity not requiring new medications or other medical or surgical intervention in the past 3 months are not exclusionary.
  • Administration or planned administration of blood products or licensed non-SARS-CoV-2 vaccines \<14 days prior to or within 14 days after study entry
  • Receipt of any antibody-based therapy (investigational or approved) for prophylaxis or treatment of COVID-19 in the preceding 6 months
  • Receipt of immunoglobulin therapy in the year prior to study entry or scheduled or anticipated immunoglobulin administration during the study period.
  • Prior receipt of any non-mRNA SARS-CoV-2 vaccine
  • Receipt of any SARS-CoV-2 vaccination in the 120 days prior to study entry
  • Documented SARS-CoV-2 infection in the 120 days prior to study entry
  • History of anaphylaxis, urticaria, or other significant adverse reaction requiring medical intervention (medications requiring a prescription or surgical intervention) after receipt of a vaccine or intervention that includes one or more of the same components contained in the study product
  • Have participated in an interventional clinical study within 28 days prior to screening (based on medical history interview) or plans to do so while participating in this study
  • Any clinical concerns as determined by the investigator that might affect the potential participant's safety in the study.

Trial locations and contacts

2 sites in 1 country. Contact the study team or a site near you to ask about taking part.

Kara Chew, MD, MS contact

310-825-0796

kchew@mednet.ucla.edu

Stephanie Buchbinder, MPH contact

310-825-5147

SBuchbinder@mednet.ucla.edu

United States2 sites, 2 recruiting

  • UCLA Westwood

    Los Angeles, California, 90095

    Kevin Pizarro, 310-843-2015, CAREOutreach@mednet.ucla.edu

    Kara Chew, MD, MS

    Recruiting

  • UCSF Community and Clinical Research Center

    San Francisco, California, 94110

    Rebecca Hoh, 415-353-9599, CONTENDER@ucsf.edu

    Steven Deeks, MD

    Recruiting

Other trials in United States

About this study

The goal of this clinical trial is to test two investigational COVID-19 booster vaccines, called CoTend-s3BXBB and CoTend-BXBB, in healthy volunteers ages 40-64. The CoTend-s3BXBB vaccine includes a component called "s3", which was designed to improve the body's response to the vaccine. CoTend-BXBB is the same vaccine without s3.

The main questions the study aims to answer are: 1) Is the investigational vaccine safe? 2) Does "s3" lead to bigger, broader, and longer-lasting responses to the vaccine?

5 different doses of the vaccines will be studied. Participants will receive a single dose of either CoTend-s3BXBB, CoTend-BXBB, or placebo. Participants will be monitored for side effects. Saliva, nasal, and blood samples will be collected and immune responses to the vaccine will be measured.

Being tested
CoTend-BXBB (SARS2-30404), CoTend-s3BXBB (SARS2-17032), Placebo
Keywords
COVID-19, SARS-CoV-2, Vaccine, Adjuvant, Virus, RNA Virus Infections, Prevention, Immunogenicity, Immunity, Viral infection, Coronavirus Infection, Infection, Coronavirus Infections
Medical subject headings
COVID-19, Virus Diseases, RNA Virus Infections, Coronavirus Infections, Infections

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • CoTend-BXBB (SARS2-30404)Biological

    Ad35-vectored SARS-CoV-2 RBD (XBB.1.5) vaccine

  • CoTend-s3BXBB (SARS2-17032)Biological

    Ad35-vectored s3-SARS-CoV-2 RBD (XBB.1.5) vaccine

  • PlaceboBiological

    Sterile sodium chloride 0.9% for injection, preservative free

Study groups in NCT06810934
Study groupRoleWhat they receive
Dose Cohort 1, Arm 1AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^6 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 1, Arm 1BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^6 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 2, Arm 2AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^7 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 2, Arm 2BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^7 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 3, Arm 3AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^8 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 3, Arm 3BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^8 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 4, Arm 4AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^9 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 4, Arm 4BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^9 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 5, Arm 5AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^10 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 5, Arm 5BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^10 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 6, Arm 6AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^9 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 6, Arm 6BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^9 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 6, Arm 6CPlacebo comparatorIntervention: Placebo (normal saline) Dose: 0.5mL IM once
Receives: Biological: Placebo
Dose Cohort 7, Arm 7AExperimentalIntervention: CoTend-s3BXBB (SARS2-17032) Dose: 1x10^10 vp (0.5mL) IM once
Receives: Biological: CoTend-s3BXBB (SARS2-17032)
Dose Cohort 7, Arm 7BExperimentalIntervention: CoTend-BXBB (SARS2-30404) Dose: 1x10^10 vp (0.5mL) IM once
Receives: Biological: CoTend-BXBB (SARS2-30404)
Dose Cohort 7, Arm 7CPlacebo comparatorIntervention: Placebo (normal saline) Dose: 0.5mL IM once
Receives: Biological: Placebo

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Frequency of solicited local reactogenicity adverse events (AEs) within 7 days after dosing.

    Number of participants with solicited local reactogenicity AEs (injection site pain, erythema, or swelling) within 7 days after dosing. An AE is any untoward medical occurrence in a clinical investigation of a patient administered a pharmaceutical product and that does not necessarily have a causal relationship with the treatment.

    Measured: 7 days

  2. Frequency of solicited systemic reactogenicity AEs within 7 days after dosing.

    Number of participants with solicited systemic reactogenicity AEs (malaise, participant-measured body temperature, fatigue, headache, chills, nausea, muscle aches/pain, joint pain) within 7 days after dosing.

    Measured: 7 days

  3. Frequency of unsolicited AEs within 28 days after dosing.

    Number of participants with unsolicited AEs within 28 days after dosing. Unsolicited AEs are AEs that were not pre-defined as solicited.

    Measured: 28 days

  4. Frequency of serious adverse events (SAEs) within 28 days after dosing.

    Number of participants with an SAE within 28 days after dosing. An SAE is defined as any adverse event that results in any of the following outcomes: death during a period of surveillance defined by the protocol, a life-threatening adverse experience, inpatient hospitalization or prolongation of existing hospitalization, a persistent or significant disability/incapacity, or a congenital anomaly/birth defect. The following are also considered SAEs for this study: severe COVID-19, defined as COVID-19 requiring hospitalization or supplemental oxygen, myocarditis or pericarditis within 6 weeks of study vaccination, and acute or new onset thrombosis or thromboembolism within 60 days of vaccination.

    Measured: 28 days

  5. Frequency of adverse events of special interest (AESIs) within 28 days after dosing.

    Number of participants with AESIs. AESIs defined as: thrombotic or thromboembolic events, thrombosis with thrombocytopenia syndrome, immune thrombocytopenia, or capillary leak syndrome occurring within 60 days; new thrombocytopenia <150 x 10^9/L or below the lower laboratory limit of normal or worsening in grade of thrombocytopenia within 60 days after study vaccination; new D-dimer elevation >2000 ng/mL within 60 days; laryngospasm, bronchospasm, or anaphylaxis assessed as at least possibly related; generalized urticaria assessed as related; any other grade allergic/ hypersensitivity reaction within 7 days; any ulceration, abscess, or necrosis at injection site assessed as possibly related; myocarditis or pericarditis occurring within 6 weeks; new diagnosis of Guillain-Barré syndrome occurring within 60 days; any new or worsened immune mediated medical condition; grade 3+ lab abnormality for which there is a reasonable possibility of causal relationship to study treatment.

    Measured: 28 days

  6. Frequency of medically attended adverse events (MAAEs) within 28 days after dosing.

    Number of participants with MAAEs (MAAE defined as an AE resulting in a hospitalization, emergency room visit, or otherwise unscheduled visit with medical personnel for any reason) within 28 days after dosing.

    Measured: 28 days

  7. Geometric mean titers (GMTs) of serum anti-XBB.1.5 neutralizing antibodies (NAb) through week 8.

    Serum anti-XBB.1.5 NAb GMT

    Measured: 8 weeks

  8. Proportion of participants achieving serum anti-XBB.1.5 NAb titers of 1:250 or better through week 8.

    Proportion of participants achieving serum anti-XBB.1.5 NAb titers of 1:250 or better

    Measured: 8 weeks

  9. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-XBB.1.5 NAb responses.

    Geometric mean fold rise (GMFR) in serum anti-XBB.1.5 NAb levels

    Measured: Pre-dose to 8 weeks

Secondary outcomes (48)

  1. Serum anti-D614G NAb GMTs through week 8.

    Serum anti-D614G NAb GMTs

    Measured: 8 weeks

  2. Serum anti-JN.1* NAb GMTs through week 8.

    Serum anti-JN.1* NAb GMTs (*the most relevant SARS-CoV-2 variant at the time of analysis will be evaluated)

    Measured: 8 weeks

  3. Proportion of participants achieving anti-D614G NAb titers of 1:250 or better through week 8.

    Proportion of participants achieving anti-D614G NAb titers of 1:250 or better

    Measured: 8 weeks

  4. Proportion of participants achieving anti-JN.1* NAb titers of 1:250 or better through week 8.

    Proportion of participants achieving serum anti-JN.1* NAb GMTs of 1:250 or better (*the most relevant SARS-CoV-2 variant at the time of analysis will be evaluated).

    Measured: 8 weeks

  5. GMFR from pre-dose to week 8 in serum anti-D614G NAb responses.

    GMFR in serum anti-D614G NAb responses

    Measured: Pre-dose to 8 weeks

  6. GMFR from pre-dose to week 8 in serum anti-JN.1* NAb responses.

    GMFR in serum anti-JN.1* NAb responses (*the most relevant SARS-CoV-2 variant at the time of analysis will be evaluated).

    Measured: Pre-dose to 8 weeks

  7. Serum anti-XBB.1.5 RBD IgG binding antibody (bAb) GMTs through week 8.

    Serum anti-XBB.1.5 RBD IgG bAb GMTs

    Measured: 8 weeks

  8. Serum anti-XBB.1.5 RBD IgA binding antibody GMTs through week 8.

    Serum anti-XBB.1.5 RBD IgA bAb GMTs

    Measured: 8 weeks

  9. Serum anti-D614G RBD IgG binding antibody (bAb) GMTs through week 8.

    Serum anti-D614G RBD IgG bAb GMTs.

    Measured: 8 weeks

  10. Serum anti-D614G RBD IgA binding antibody (bAb) GMTs through week 8.

    Serum anti-D614G RBD IgA bAb GMTs through week 8.

    Measured: 8 weeks

  11. Serum anti-JN.1* RBD IgG binding antibody (bAb) GMTs through week 8.

    Serum anti-JN.1* RBD IgG bAb GMTs (*the most relevant SARS-CoV-2 variant at the time of analysis will be evaluated)

    Measured: 8 weeks

  12. Serum anti-JN.1* RBD IgA binding antibody (bAb) GMTs through week 8.

    Serum anti-JN.1* RBD IgA bAb GMTs (*the most relevant SARS-CoV-2 variant at the time of analysis will be evaluated)

    Measured: 8 weeks

  13. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-XBB.1.5 RBD IgG binding antibody responses.

    Measured: Pre-dose to 8 weeks

  14. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-XBB.1.5 RBD IgA binding antibody responses.

    Measured: Pre-dose to 8 weeks

  15. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-D614G RBD IgG binding antibody responses.

    Measured: Pre-dose to 8 weeks

  16. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-D614G RBD IgA binding antibody responses.

    Measured: Pre-dose to 8 weeks

  17. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-JN.1* RBD IgG binding antibody responses.

    Measured: Pre-dose to 8 weeks

  18. Geometric mean fold rise (GMFR) from pre-dose to week 8 in serum anti-JN.1* RBD IgA binding antibody responses.

    Measured: Pre-dose to 8 weeks

  19. Frequency of grade 3 or higher AEs through week 26 visit.

    Number of participants with grade 3 or higher AEs through week 26 visit. Grade 3 AE is defined as severe symptoms causing inability to perform usual social and functional activities with intervention or hospitalization indicated. Grade 4 AE is defined as potentially life-threatening symptoms causing inability to perform basic self-care functions with intervention indicated to prevent permanent impairment, persistent disability, or death. All deaths related to an AE are classified as grade 5.

    Measured: 26 weeks

  20. Frequency of SAEs through week 26 visit.

    Number of participants with SAEs through week 26 visit.

    Measured: 26 weeks

  21. Frequency of AESIs through week 26 visit.

    Number of participants with AESIs through week 26 visit.

    Measured: 26 weeks

  22. Frequency of MAAEs through week 26 visit.

    Number of participants with MAAEs through week 26 visit

    Measured: 26 weeks

  23. Frequency of SAEs through end of study visit

    Number of participants with SAEs through their end of study visit

    Measured: Through end of study visit (52 or 104 weeks)

  24. Frequency of AESIs through end of study visit

    Number of participants with AESIs through their end of study visit

    Measured: Through end of study visit (52 or 104 weeks)

  25. Frequency of MAAEs through end of study visit

    Number of participants with MAAEs through their end of study visit

    Measured: Through end of study visit (52 or 104 weeks)

  26. Fraction of RBD-specific CD4+ T cells through week 8.

    Fraction of RBD-specific CD4+ T cells

    Measured: 8 weeks

  27. Fraction of RBD-specific CD8+ T cells through week 8.

    Fraction of RBD-specific CD8+ T cells

    Measured: 8 weeks

  28. NAb GMTs through week 26.

    Serum NAb GMTs

    Measured: 26 weeks

  29. NAb GMTs through week 52.

    Serum NAb GMTs

    Measured: 52 weeks

  30. NAb GMTs through week 104.

    Serum NAb GMTs

    Measured: 104 weeks

  31. Binding Ab GMTs through week 26.

    Serum binding Ab GMTs

    Measured: 26 weeks

  32. Binding Ab GMTs through week 52.

    Serum binding Ab GMTs

    Measured: 52 weeks

  33. Binding Ab GMTs through week 104.

    Serum binding Ab GMTs

    Measured: 104 weeks

  34. Proportion of participants achieving NAb titers of 1:250 or better through week 26.

    Proportion of participants achieving serum NAb titers of 1:250 or better

    Measured: 26 weeks

  35. Proportion of participants achieving NAb titers of 1:250 or better through week 52.

    Proportion of participants achieving serum NAb titers of 1:250 or better

    Measured: 52 weeks

  36. Proportion of participants achieving NAb titers of 1:250 or better through week 104.

    Proportion of participants achieving serum NAb titers of 1:250 or better

    Measured: 104 weeks

  37. GMFR of NAb titers from pre-dose through week 26.

    GMFR of serum NAb titers

    Measured: Pre-dose to 26 weeks

  38. GMFR of NAb titers from pre-dose through week 52.

    GMFR of serum NAb titers

    Measured: Pre-dose to 52 weeks

  39. GMFR of NAb titers from pre-dose through week 104.

    GMFR of serum NAb titers

    Measured: Pre-dose to 104 weeks

  40. GMFR of binding Ab titers from pre-dose through week 26.

    Measured: Pre-dose to 26 weeks

  41. GMFR of binding Ab titers from pre-dose through week 52.

    Measured: Pre-dose to 52 weeks

  42. GMFR of binding Ab titers from pre-dose through week 104.

    Measured: Pre-dose to 104 weeks

  43. Fraction of RBD-specific CD4+ T cells through week 26.

    Fraction of RBD-specific CD4+ T cells

    Measured: 26 weeks

  44. Fraction of RBD-specific CD4+ T cells through week 52.

    Fraction of RBD-specific CD4+ T cells

    Measured: 52 weeks

  45. Fraction of RBD-specific CD4+ T cells through week 104.

    Fraction of RBD-specific CD4+ T cells

    Measured: 104 weeks

  46. Fraction of RBD-specific CD8+ T cells through week 26.

    Fraction of RBD-specific CD8+ T cells

    Measured: 26 weeks

  47. Fraction of RBD-specific CD8+ T cells through week 52.

    Fraction of RBD-specific CD8+ T cells

    Measured: 52 weeks

  48. Fraction of RBD-specific CD8+ T cells through week 104.

    Fraction of RBD-specific CD8+ T cells

    Measured: 104 weeks

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted6 Feb 2025
  2. Study start21 Oct 2025
  3. Primary completionDec 2027 (estimated)
  4. Study completionOct 2029 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 1/2
Primary purpose
Prevention
Allocation
Randomised
Intervention model
Parallel groups
Masking
Quadruple blind
Who is masked
Participant, Care provider, Investigator, Outcomes assessor
Enrolment
80 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06810934
Sponsor's protocol ID
23-001884
Other IDs
1U01AI172800-01A1
Acronym
CONTENDER
Status last verified
Aug 2026
First submitted
9 Oct 2024
Last updated
18 Aug 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
Yes: De-identified data.

Publications

  • Bowen JE, Park YJ, Stewart C, Brown JT, Sharkey WK, Walls AC, Joshi A, Sprouse KR, McCallum M, Tortorici MA, Franko NM, Logue JK, Mazzitelli IG, Nguyen AW, Silva RP, Huang Y, Low JS, Jerak J, Tiles SW, Ahmed K, Shariq A, Dan JM, Zhang Z, Weiskopf D, Sette A, Snell G, Posavad CM, Iqbal NT, Geffner J, Bandera A, Gori A, Sallusto F, Maynard JA, Crotty S, Van Voorhis WC, Simmerling C, Grifantini R, Chu HY, Corti D, Veesler D. SARS-CoV-2 spike conformation determines plasma neutralizing activity elicited by a wide panel of human vaccines. Sci Immunol. 2022 Dec 23;7(78):eadf1421. doi: 10.1126/sciimmunol.adf1421. Epub 2022 Dec 23.

    PubMed 36356052

  • De Boer RJ, Perelson AS. How Germinal Centers Evolve Broadly Neutralizing Antibodies: the Breadth of the Follicular Helper T Cell Response. J Virol. 2017 Oct 27;91(22):e00983-17. doi: 10.1128/JVI.00983-17. Print 2017 Nov 15.

    PubMed 28878083

  • Wang Q, Iketani S, Li Z, Liu L, Guo Y, Huang Y, Bowen AD, Liu M, Wang M, Yu J, Valdez R, Lauring AS, Sheng Z, Wang HH, Gordon A, Liu L, Ho DD. Alarming antibody evasion properties of rising SARS-CoV-2 BQ and XBB subvariants. Cell. 2023 Jan 19;186(2):279-286.e8. doi: 10.1016/j.cell.2022.12.018. Epub 2022 Dec 14.

    PubMed 36580913

  • Havervall S, Marking U, Svensson J, Greilert-Norin N, Bacchus P, Nilsson P, Hober S, Gordon M, Blom K, Klingstrom J, Aberg M, Smed-Sorensen A, Thalin C. Anti-Spike Mucosal IgA Protection against SARS-CoV-2 Omicron Infection. N Engl J Med. 2022 Oct 6;387(14):1333-1336. doi: 10.1056/NEJMc2209651. Epub 2022 Sep 14. No abstract available.

    PubMed 36103621

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Questions about this trial

What is this clinical trial studying?

A Phase 1/2 study testing CoTend-BXBB (SARS2-30404) and CoTend-s3BXBB (SARS2-17032) in people with COVID-19 and SARS-CoV-2 Infection, run by Kara Chew at 2 sites in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 18 inclusion and 35 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 18 Aug 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 2 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. Some participants in this study may receive a placebo. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this combined phase mean?

Phase 1 studies test a treatment in a small group of people for the first time or in a new way, mainly to check safety and find the right dose.

Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Kara Chew, MD, MS (310-825-0796, kchew@mednet.ucla.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Frequency of solicited local reactogenicity adverse events (AEs) within 7 days after dosing. (time frame: 7 days). The study lists 9 primary outcomes in all. It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06810934, which also lists 11 linked publications.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 18 Aug 2026.

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