ClinicalTrials.gg
RecruitingNCT05475925Updated Jun 17, 2026

A Study of DR-01 in Subjects With Large Granular Lymphocytic Leukemia or Cytotoxic Lymphomas

A Phase 1/2 interventional study of DR-01 in LGLL - Large Granular Lymphocytic Leukemia, Primary Cutaneous Gamma-Delta T-Cell Lymphoma and Primary Cutaneous CD8+ Aggressive Epidermotropic T-Cell Lymphoma, sponsored by Dren Bio. Recruiting at 37 sites in 9 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-06-17.

Sponsored by Dren Bio · Phase 1/2, Interventional, and Treatment

From the registry’s dates

  • Started Jul 2022; still recruiting 4 years 3 months later.
Phase
Phase 1/2
Study type
Interventional
Enrollment
200
Allocation
Non-randomized
Ages
18 Years and older
Sex
All
01

Study summary

This is a multicenter, first-in-human, Phase 1/2 study to evaluate the safety, tolerability, pharmacokinetics, pharmacodynamics, and anti-tumor activity of DR-01 in adult patients with large granular lymphocytic leukemia or cytotoxic lymphomas

02

Conditions studied

  • LGLL - Large Granular Lymphocytic Leukemia
  • Primary Cutaneous Gamma-Delta T-Cell Lymphoma
  • Primary Cutaneous CD8+ Aggressive Epidermotropic T-Cell Lymphoma
  • Hepatosplenic T-cell Lymphoma
  • Subcutaneous Panniculitis-Like T-Cell Lymphoma
  • Aggressive NK Cell Leukemia
  • Systemic EBV1 T-cell Lymphoma, if CD8 Positive
  • Hydroa Vacciniforme-Like Lymphoproliferative Disorder
  • Extranodal NK/T Cell Lymphoma, Nasal Type
  • Enteropathy-Associated T-Cell Lymphoma
  • Monomorphic Epitheliotropic Intestinal T-Cell Lymphoma
  • Cytotoxic PTCL-NOS (CD8+ or CD56+ and Cytotoxic Marker)
  • Cutaneous PTCL-NOS (CD8+ or CD56+ and Cytotoxic Marker)

Keywords

  • LGLL
  • Cytotoxic
  • Lymphoma
  • ANKL
  • EATL
  • MEITL
  • ENKL
  • HSTCL
  • Leukemia
  • SPTCL
  • ENKTL
  • CTCL
  • PTCL-NOS
  • TCL
03

In context

Leukemia, Large Granular Lymphocytic

144 studies on the registry are indexed under Leukemia, Large Granular Lymphocytic; 19 are open to participants now.

This study's planned enrollment of 200 is above the median of 37 across 102 interventional studies indexed under Leukemia, Large Granular Lymphocytic.

Browse Leukemia, Large Granular Lymphocytic studies →

Lead sponsor

Dren Bio is the lead sponsor of 7 studies on the registry; 4 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. ≥18 years of age.
  2. Able to understand and comply with protocol-required study procedures and voluntarily sign a written document.
  3. Sufficient key organ performance and coagulation.
  4. Female subjects of (postmenarcheal, has an intact uterus and at least one ovary, and is \<1 year ) must agree to use a highly effective method of from enrollment through at least 12 months after last dose of DR-01.
  5. Male subjects must agree to use acceptable effective method(s) of contraception.

    Subjects with LGLL must also meet inclusion criteria 6 and 7.

  6. Must have discontinued at least one .
  7. Additional immunophenotypic and symptomatic criteria must be met.

    Disease-specific Inclusion Criteria (Cytotoxic Lymphomas):

    Subjects with cytotoxic lymphomas must also meet inclusion criteria 8,9, and 10.

  8. Subjects must have failed at least one prior systemic regimens.
  9. Availability of post-progression tissue sample or willingness to consent to a baseline .
  10. confirmed diagnosis of a cytotoxic lymphoma by a hematopathologist (according to the WHO 2016 classification [Swerdlow 2016]).
  11. For Part A only, evaluable disease is acceptable.
  12. For Part B2 only, evaluable by the following response criteria as documented during Screening:

    1. For cytotoxic PTCL-NOS, ENKTL, MEITL, EATL, SPTCL - Subjects must have radiographically by computed tomography (CT) or CT/positron emission tomography (PET) scan defined as at least one node measuring >1.5 cm or measurable extranodal lesion of at least 1.0 cm in longest diameter to be evaluated by Lugano criteria (Cheson 2014).
    2. For PCGDTCL, ET-CTCL, HVLPD, cytotoxic CuPTCL-NOS - Subjects with primary cutaneous variants must have at least 1 measurable lesion that is evaluable using the Olsen criteria (Olsen 2021) or have leukemic involvement that can be evaluated using modified TPLL response criteria (Staber 2019).
    3. For HSTCL, ANKL, SysEBV TCL - Subjects with hepatosplenic disease without measurable disease by Lugano criteria (Cheson 2014) or leukemic involvement in BM or peripheral blood that is evaluable for response using a modified TPLL response criteria (Staber 2019).

Exclusion criteria

Exclusion Criteria:

Disease-specific Exclusion Criteria; LGLL and ANKL:

  1. A reactive LGL lymphocytosis to a viral infection or LGL associated with myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML).

    The following exclusion criteria apply to all subjects:

  2. Active systemic infection or severe localized infection requiring systemic antibiotics, antivirals or antifungals.
  3. Active or suspected malignant central nervous system involvement.
  4. Life-threatening, severe complications of (e.g., uncontrolled bleeding, pneumonia with hypoxia or shock, and/or disseminated intravascular coagulation).
  5. Active known second malignancy.
  6. Infection with (HIV) type 1 or 2 (HIV-1 or HIV-2).
  7. infection (hepatitis B virus surface antigen [HBsAg] positive), or (hepatitis C virus [HCV] antibody positive, confirmed by HCV ribonucleic acid). Subjects with HCV with undetectable virus after treatment are eligible.
  8. History of cardiac disease or congestive heart failure greater than (NYHA) Class II.
  9. Use of systemic at prohibited dose levels within 15 days prior to C1D1 (except for prophylaxis for radiodiagnostic contrast reactions and study-defined premedication) or use of other non-biological drugs within 15 days or 5 half-lives (whichever is less) prior to C1D1.
  10. Any condition requiring hormonal therapy (except for , hormone replacement therapy and hormonal prophylaxis for a prior malignancy).
  11. Any other medical or psychiatric condition, or laboratory abnormality that would increase the risk associated with study participation, in the opinion of the Investigator or Medical Monitor.
  12. Toxicities from previous anticancer therapies must have resolved to baseline levels or to Grade 1 (except for alopecia, peripheral neuropathy, or hematologic parameters meeting inclusion criteria).
  13. HSCT within 40 days of C1D1, allogeneic HSCT within 90 days
  14. Any immunosuppressive therapy for for subjects who are post allogeneic HSCT.
  15. Major surgery within 28 days of C1D1 (requires more than local anesthesia or plexus blockade).
Terms in these criteria, in plain language(18)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Childbearing potential

Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).

Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Line of therapy

A line of therapy is one course of treatment, which may combine several drugs. First-line is the first course given; second-line follows when that stops working or is not tolerated.

“Two prior lines” means two courses that count separately under the study’s rules — not simply two drugs. Ask the study team if you are unsure how yours are counted.

Biopsy and archival tissue

A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.

Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.

Histologically or cytologically confirmed

The diagnosis was confirmed by looking at a sample under a microscope: tissue from a biopsy or surgery (histology), or cells from a fluid or needle sample (cytology).

Your pathology report is the document that shows this.

Measurable disease

The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.

The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

HIV

The human immunodeficiency virus, which weakens the immune system.

Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.

Hepatitis B tests

Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.

Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.

Hepatitis C tests

Hepatitis C is a virus that infects the liver. An HCV antibody test can stay positive after an infection has cleared (and is occasionally positive without one); an HCV RNA test shows whether the virus is there now.

After treatment, hepatitis C counts as cured when HCV RNA is still undetectable 12 weeks or more after the treatment ended. Studies often accept people cured this way.

Clinically significant

Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.

NYHA class (heart failure)

The New York Heart Association’s four classes of how much heart failure limits physical activity.

I
No limits: ordinary activity causes no undue tiredness or breathlessness.
II
Slight limits: comfortable at rest, ordinary activity causes symptoms.
III
Marked limits: comfortable at rest, less than ordinary activity causes symptoms.
IV
Symptoms even at rest; any activity makes them worse.

Studies set their own limit — many outside heart failure leave out class III–IV, while heart failure studies may ask for a particular class. Check the class this study names.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Immunosuppression

A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.

Read whether the line is about a condition or about medicines, and which medicines and doses it means.

Allogeneic and autologous transplant

Stem cell (bone marrow) transplants. Allogeneic uses cells from a donor; autologous uses your own cells, collected earlier and given back.

GVHD (graft-versus-host disease)

After a transplant from a donor, the donor’s immune cells attack the recipient’s body, often the skin, gut or liver.

05

Study design

Phase
Phase 1 / Phase 2
Primary purpose
Treatment
Allocation
Non-randomized
Intervention model
Sequential assignment
Masking
None (open label)
Enrollment
200 participants (estimated)

Study arms

  • Experimental
    Part A Dose Escalation 1 mg/kg of DR-01

    Subjects in this arm will initially receive 1 mg/kg at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing (up to 6 mg/kg) thereafter for up to 25 cycles total.

    Drug: DR-01

  • Experimental
    Part A Dose Escalation 3 mg/kg of DR-01

    Subjects in this arm will initially receive 3 mg/kg at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing (up to 10 mg/kg) thereafter for up to 25 cycles total.

    Drug: DR-01

  • Experimental
    Part A Dose Escalation 6 mg/kg of DR-01

    Subjects in this arm will initially receive 6 mg/kg at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing (up to 10 mg/kg) thereafter for up to 25 cycles total.

    Drug: DR-01

  • Experimental
    Part A Dose Escalation 10 mg/kg of DR-01

    Subjects in this arm will initially receive 10 mg/kg at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing (up to 10 mg/kg) thereafter for up to 25 cycles total.

    Drug: DR-01

  • Experimental
    Part A Dose De-escalation 0.3 to <1 mg/kg of DR-01

    This cohort would only be triggered should a DLT occur at Dose Level 1 or if recommended by the Safety Review Committee. Subjects in this arm would initially receive 0.3 to \<1 mg/kg at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing (up to 3 mg/kg) thereafter for up to 25 cycles total.

    Drug: DR-01

  • Experimental
    Part B Dose Expansion (Cohort B1) Optimized Dose/Regimen of DR-01

    Subjects in this arm will receive the pharmacologically optimized dose/regimen for LGL leukemia subjects determined in Part A. Depending on the selected dose/regimen, subjects will receive target dose at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing thereafter for up to 25 doses total.

    Drug: DR-01

  • Experimental
    Part B Dose Expansion (Cohort B2) Optimized Dose/Regimen of DR-01

    Subjects in this arm will receive the pharmacologically optimized dose/regimen for cytotoxic lymphoma subjects determined in Part A. Depending on the selected dose/regimen, subjects will receive target dose at either the Primary regimen (bi-weekly dosing for fist month), Secondary regimen (doses at Days 1, 8, 15, 29 during first month), or Tertiary regimen (dosing days 1-5, 15, 29 during first month), followed by monthly dosing thereafter for up to 25 doses total.

    Drug: DR-01

Interventions

  • DrugDR-01

    DR-01 is a non-fucosylated, human immunoglobulin G1 (IgG1) monoclonal antibody.

06

What researchers measure

Primary outcomes

  1. Part A: Safety and Tolerability. To determine the incidence and severity of adverse events as assessed by CTCAE v5.0.

    Time frame: Up to 25 months

  2. Part A: Safety and Tolerability. To determine the incidence and severity of dose limiting toxicities (DLTs) as defined by protocol specified DLT criteria.

    Time frame: During First 28 days (Cycle 1)

  3. Part A: To determine potential pharmacologically optimized dose/regimen for DR-01 in LGL leukemia and cytotoxic lymphoma populations as determined using an integrated assessment of efficacy, safety, PK/PD, and exposure-response relationships.

    Time frame: Up to 6 months

  4. Part B: Overall Response Rate (ORR), defined as the proportion of subjects with Complete Response (CR) or Partial Response (PR) based on disease-specific response criteria.

    Time frame: Up to 24 months

07

Study locations

36 of 37 sites recruiting
  • Dren Investigational Site
    Birmingham, Alabama 35233, United States
    Recruiting
  • Dren Investigational Site
    Duarte, California 91010, United States
    Recruiting
  • Dren Investigational Site
    Irvine, California 92612, United States
    Recruiting
  • Dren Investigational Site
    Redwood City, California 94063, United States
    Recruiting
  • Dren Investigational Site
    New Haven, Connecticut 06519, United States
    Recruiting
  • Dren Investigational Site
    Tampa, Florida 33612, United States
    Recruiting
  • Dren Investigational Site
    Boston, Massachusetts 02114, United States
    Recruiting
  • Dren Investigational Site 1
    New York, New York 10021, United States
    Recruiting
  • Dren Investigational Site 2
    New York, New York 10032, United States
    Not yet recruiting
  • Dren Investigational Site
    Columbus, Ohio 43210, United States
    Recruiting
  • Dren Investigational Site 2
    Pittsburgh, Pennsylvania 15213, United States
    Recruiting
  • Dren Investigational Site
    Houston, Texas 77030, United States
    Recruiting
  • Dren Investigational Site
    Charlottesville, Virginia 22903, United States
    Recruiting
  • Dren Investigational Site
    Fairfax, Virginia 22031, United States
    Recruiting
  • Dren Investigational Site
    Seattle, Washington 98109, United States
    Recruiting
  • Dren Investigational Site
    Clayton, Victoria 3168, Australia
    Recruiting
  • Dren Investigational Site
    Richmond, Victoria 3121, Australia
    Recruiting
  • Dren Investigational Site
    Nedlands, Washington 6009, Australia
    Recruiting
  • Dren Investigational Site
    Pierre-Bénite, 69310, France
    Recruiting
  • Dren Investigational Site
    Rennes, 35000, France
    Recruiting
  • Dren Investigational Site
    Toulouse, 31059, France
    Recruiting
  • Dren Investigational Site
    Berlin, 10117, Germany
    Recruiting
  • Dren Investigational Site
    Cologne, 50937, Germany
    Recruiting
  • Dren Investigational Site
    Leipzig, 04103, Germany
    Recruiting
  • Dren Investigational Site 1
    Hong Kong, Hong Kong, Hong Kong
    Recruiting
  • Dren Investigational Site 2
    Hong Kong, Hong Kong
    Recruiting
  • Dren Investigational Site
    Bologna, 40126, Italy
    Recruiting
  • Dren Investigational Site 1
    Busan, South Korea
    Recruiting
  • Dren Investigational Site 2
    Busan, South Korea
    Recruiting
  • Dren Investigational Site
    Goyang-si, South Korea
    Recruiting
  • Dren Investigational Site 1
    Seoul, South Korea
    Recruiting
  • Dren Investigational Site 2
    Seoul, South Korea
    Recruiting
  • Dren Investigational Site 3
    Seoul, South Korea
    Recruiting
  • Dren Investigational Site
    Barcelona, 08035, Spain
    Recruiting
  • Dren Investigational Site
    Salamanca, 37007, Spain
    Recruiting
  • Dren Investigational Site
    Tainan, Taiwan
    Recruiting
  • Dren Investigational Site
    Taipei, Taiwan
    Recruiting
08

References and documents

Individual participant data

Plan to share: No

No publications or documents are linked to this record.

09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jun 17, 2026, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05475925
Lead sponsor
Dren Bio
Responsible party
Sponsor
First posted
Jul 27, 2022
Start date
Jul 13, 2022
Primary completion
Dec 2026 (estimated)
Completion
Dec 2026 (estimated)
Last update
Jun 17, 2026

Study contacts

Dren Central Contact
Contact
DR-01-ONC-001_inquiries@drenbio.com
415-737-5277
Wan-Jen Hong, MD
study director · Dren Bio

Oversight

Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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