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CompletedNCT00065260Updated Jul 21, 2021Results posted

Rabbit Antithymocyte Globulin Versus Campath-1H for Treating Severe Aplastic Anemia

A Phase 2 interventional study of Campath-1H and r-ATG in Aplastic Anemia, sponsored by National Heart, Lung, and Blood Institute (NHLBI). Completed at 1 site in United States. Open to participants aged 2 Years and older. Per ClinicalTrials.gov, last updated 2021-07-21.

Sponsored by National Heart, Lung, and Blood Institute (NHLBI) · Phase 2, Interventional, and Treatment

Phase
Phase 2
Study type
Interventional
Enrollment
54
Allocation
Randomized
Ages
2 Years and older
Sex
All
01

Study summary

Severe aplastic anemia, characterized by pancytopenia and a hypocellular bone marrow, is effectively treated by immunosuppressive therapy, usually a combination of antithymocyte globulin (ATG) and cyclosporine (CsA). Survival rates following this regimen are equivalent to those achieved with allogeneic stem cells transplantation. However, approximately 1/3 of patients will not show blood count improvement after ATG/CsA. General experience and small pilot studies have suggested that such patients may benefit from further immunosuppression. Furthermore, analysis of our own clinical data suggest that patients with poor blood count responses to a single course of ATG, even when transfusion-independence is achieved, have a markedly worse prognosis than patients with robust hematologic improvement. The management of such cases is uncertain.

This study will enroll patients who are either refractory to h-ATG (continued severe pancytopenia) or who have only modest improvement in blood counts (weak hematologic responders) to receive a further immunosuppressive therapy, delivered either as rabbit ATG (Thymoglobulin, r-ATG) or a humanized monoclonal antibody to T-cells, alemtuzumab (Campath-1H ). Primary endpoint will be response rate at 3 months defined as no longer meeting criteria for severe aplastic anemia. Relapse, robustness of hematopoietic recovery at 3 months, survival and clonal evolution to paroxysmal nocturnal hemoglobinuria (PNH), myelodysplasia and acute leukemia will be the secondary endpoints.

Read the detailed description

Severe aplastic anemia, characterized by pancytopenia and a hypocellular bone marrow, is effectively treated by immunosuppressive therapy, usually a combination of antithymocyte globulin (ATG) and cyclosporine (CsA). Survival rates following this regimen are equivalent to those achieved with allogeneic stem cells transplantation. However, approximately 1/3 of patients will not show blood count improvement after ATG/CsA. General experience and small pilot studies have suggested that such patients may benefit from further immunosuppression. Furthermore, analysis of our own clinical data suggest that patients with poor blood count responses to a single course of ATG, even when transfusion-independence is achieved, have a markedly worse prognosis than patients with robust hematologic improvement. The management of such cases is uncertain.

This study will enroll patients who are either refractory to h-ATG (continued severe pancytopenia) or who have only modest improvement in blood counts (weak hematologic responders) to receive further immunosuppressive therapy, delivered either as rabbit ATG (Thymoglobulin , r-ATG) or a humanized monoclonal antibody to T-cells, alemtuzumab (Campath-1H ). Primary endpoint will be response rate at 6 months defined as no longer meeting criteria for severe aplastic anemia. Relapse, robustness of hematopoietic recovery at 6 months, survival and clonal evolution to paroxysmal nocturnal hemoglobinuria (PNH), myelodysplasia and acute leukemia will be the secondary endpoints.

02

Conditions studied

  • Aplastic Anemia

Keywords

  • Alemtuzumab (Campath-1H)
  • Rabbit ATG
  • Severe Aplastic Anemia
  • Cyclosporine
  • Thrombocytopenia
  • Leukopenia
  • Neutropenia
  • Autoimmunity
  • Relapse
  • Anemia
03

In context

Anemia

1,733 studies on the registry are indexed under Anemia; 246 are open to participants now.

This study's enrollment of 54 is below the median of 94 across 1,291 interventional studies indexed under Anemia.

Browse Anemia studies →

Lead sponsor

National Heart, Lung, and Blood Institute (NHLBI) is the lead sponsor of 1,117 studies on the registry; 71 are open to participants now.

Of its 57 completed or terminated interventional studies of FDA-regulated products, 49 (86%) have results posted.

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

04

Who can participate

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

Inclusion criteria

Severe aplastic anemia confirmed at NIH by:

Bone marrow cellularity less than 30% (excluding lymphocytes)

At least two of the following:

Absolute neutrophil count less than 500/microL;

Platelet count less than 20,000/ microL;

Reticulocyte count less than 60,000/ microL.

Severe aplastic anemia refractory to prior course(s) of h-ATG/CsA defined after 3 months from treatment with less or equal to 4 years from receiving h-ATG.

OR

Suboptimal response to initial immunosuppression with h-ATG/CsA as defined by platelet and reticulocyte count less than 50,000 /microL at 3 months.

Age greater than or equal to 2 years of age

Exclusion criteria

EXCLUSION CRITERIA:

Diagnosis of Fanconi anemia.

Evidence of a clonal disorder on cytogenetics. Patients with super severe neutropenia (ANC less than 200/microL) will not be excluded initially if results of cytogenetics are not available or pending. If evidence of a clonal disorder is later identified, the subject will go off study.

Prior treatment courses with rabbit ATG or high dose cyclophosphamide (200 mg/kg or equivalent).

Infection not adequately responding to appropriate therapy.

Underlying immunodeficiency state including seropositivity for HIV.

Failure to discontinue the herbal supplements Echinacea purpurea or Usnea barbata (Old Man's Beard) within two weeks of enrollment.

Previous hypersensitivity to Campath-1H or its components.

Moribund status or concurrent hepatic, renal, cardiac, neurologic, pulmonary, infectious, or metabolic disease of such severity that it would preclude the patient s ability to tolerate protocol therapy or that death within 7-10 days is likely.

Potential subjects with cancer who are on active chemotherapeutic treatment or who take drugs with hematological effects will not be eligible.

Serum creatinine greater than 2.5 mg/dL.

Current pregnancy or lactation or unwillingness to take contraceptives.

Inability to understand the investigational nature of the study or give informed consent.

05

Study design

Phase
Phase 2
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
54 participants (actual)

Study arms

  • Experimental
    r-ATG /cyclosporine

    A randomized trial of rabbit anti-thymocyte globulin (r-ATG)/ cyclosporine (CsA) versus Campath-1H in aplastic anemia patients with refractory pancytopenia or suboptimal hematological response after horse ATG treatment. Subjects who receive rabbit ATG/ CsA will be given rabbit ATG 3.5mg/kg/day for 5 days and CsA 10mg/kg/day orally twice daily for 6 months (15mg/kg/day for children under 12 yrs. Subjects who receive Campath-1H will receive an intravenous infusion for 10 days. Adult subjects will receive 10mg/day (children:0.2mg/kg/day).

    Drug: r-ATG · Drug: CsA

  • Experimental
    Alemtuzumab (Campath-1H)

    A randomized trial of rabbit anti-thymocyte globulin (ATG)/ cyclosporine (CsA) versus Campath-1H in aplastic anemia patients with refractory pancytopenia or suboptimal hematological response after horse ATG treatment. Subjects who receive rabbit ATG/ CsA will be given rabbit ATG 3.5mg/kg/day for 5 days and CsA 10mg/kg/day orally twice daily for 6 months (15mg/kg/day for children under 12 yrs. Subjects who receive Campath-1H will receive an intravenous infusion for 10 days. Adult subjects will receive 10mg/day (children:0.2mg/kg/day).

    Drug: Campath-1H

Interventions

  • DrugCampath-1H

    Campath-1H IV 10 days. Adults:10mg/day (children:0.2mg/kg/day).

    Also known as: Alemtuzumab

  • Drugr-ATG

    Rabbit ATG 3.5mg/kg/day for consecutive 5 days

    Also known as: Rabbit Anti-Thymoglobulin

  • DrugCsA

    CsA 10mg/kg/day orally twice daily for 6 months (15mg/kg/day for children under 12 yrs.

    Also known as: Cyclosporine

06

What researchers measure

Primary outcomes

  1. Participants no Longer Meeting Criteria for Severe Aplastic Anemia.

    Number of participants no longer meeting the criteria for severe aplastic anemia as measured by response to treatment at 6 months

    Time frame: 6 months

Secondary outcomes

  1. Number of Participants With Robust Hematologic Recovery With Reticulocyte or Platelet Count

    Number of participants with robust hematologic recovery with reticulocyte or platelet count ≥ 50,000/uL

    Time frame: 6 months

  2. Percentage of Cumulative Incidence of Relapse in Participants

    Percentage of cumulative incidence of relapse of disease in participants

    Time frame: 3 year

  3. Percentage of Cumulative Incidence of Clonal Evolution in Participants

    Percent of cumulative incidence of clonal evolution in participants to either paroxysmal nocturnal hemoglobinuria (PNH), myelodysplasia or acute leukemia.

    Time frame: 3 years

  4. Percentage of Participants no Longer Meeting Criteria for Severe Aplastic Anemia.

    Percentage of participants no longer meeting the criteria for severe aplastic anemia as measured by response to treatment

    Time frame: 3 months and 6 months

07

Results

Posted Mar 3, 2016

Participant flow

Participant flow — Overall Study
Milestoner-ATG /CyclosporineAlemtuzumab (Campath-1H)
Started2727
Completed2726
Not completed01
Withdrew: Death01

Outcome measures

PrimaryParticipants no Longer Meeting Criteria for Severe Aplastic Anemia.

Number of participants no longer meeting the criteria for severe aplastic anemia as measured by response to treatment at 6 months

Time frame:
6 months
Reported as:
Number · participants
Participants no Longer Meeting Criteria for Severe Aplastic Anemia.
participantsr-ATG /CyclosporineAlemtuzumab (Campath-1H)
No Response1817
Partial Response99
Complete Response00
SecondaryNumber of Participants With Robust Hematologic Recovery With Reticulocyte or Platelet Count

Number of participants with robust hematologic recovery with reticulocyte or platelet count ≥ 50,000/uL

Time frame:
6 months
Reported as:
Count of participants · Participants
Number of Participants With Robust Hematologic Recovery With Reticulocyte or Platelet Count
Participantsr-ATG /CyclosporineAlemtuzumab (Campath-1H)
Number of Participants With Robust Hematologic Recovery With Reticulocyte or Platelet Count99
SecondaryPercentage of Cumulative Incidence of Relapse in Participants

Percentage of cumulative incidence of relapse of disease in participants

Time frame:
3 year
Reported as:
Number · percentage of cumulative incidence
Percentage of Cumulative Incidence of Relapse in Participants
percentage of cumulative incidencer-ATG /CyclosporineAlemtuzumab (Campath-1H)
Percentage of Cumulative Incidence of Relapse in Participants199
SecondaryPercentage of Cumulative Incidence of Clonal Evolution in Participants

Percent of cumulative incidence of clonal evolution in participants to either paroxysmal nocturnal hemoglobinuria (PNH), myelodysplasia or acute leukemia.

Time frame:
3 years
Reported as:
Number · Percentage of Cumulative Incidence
Percentage of Cumulative Incidence of Clonal Evolution in Participants
Percentage of Cumulative Incidencer-ATG /CyclosporineAlemtuzumab (Campath-1H)
Percentage of Cumulative Incidence of Clonal Evolution in Participants165
SecondaryPercentage of Participants no Longer Meeting Criteria for Severe Aplastic Anemia.

Percentage of participants no longer meeting the criteria for severe aplastic anemia as measured by response to treatment

Time frame:
3 months and 6 months
Reported as:
Number · percentage of participants
Percentage of Participants no Longer Meeting Criteria for Severe Aplastic Anemia.
percentage of participantsr-ATG /CyclosporineAlemtuzumab (Campath-1H)
3 Months19 (3 to 34)19 (3 to 34)
6 Months33 (14 to 52)37 (18 to 57)

Adverse events

Collected over 3 years. Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
r-ATG /Cyclosporine9/27 (33.3%)7/27 (25.9%)7/27 (25.9%)
Alemtuzumab (Campath-1H)4/27 (14.8%)12/27 (44.4%)12/27 (44.4%)
Most frequent serious events
Most frequent serious events
Eventr-ATG /CyclosporineAlemtuzumab (Campath-1H)
infectionImmune system disorders7/2712/27
Most frequent other events
Most frequent other events
Eventr-ATG /CyclosporineAlemtuzumab (Campath-1H)
infectionBlood and lymphatic system disorders7/2712/27

Baseline characteristics

Age, Categorical
Age, Categorical(Participants)r-ATG /CyclosporineAlemtuzumab (Campath-1H)Total
<=18 years3912
Between 18 and 65 years221436
>=65 years246
Sex: Female, Male
Sex: Female, Male(Participants)r-ATG /CyclosporineAlemtuzumab (Campath-1H)Total
Female111324
Male161430
Region of Enrollment
Region of Enrollment(participants)r-ATG /CyclosporineAlemtuzumab (Campath-1H)Total
United States272754
08

Study locations

1 site
  • National Institutes of Health Clinical Center, 9000 Rockville Pike
    Bethesda, Maryland 20892, United States
09

References and documents

Publications

  • Young NS, Maciejewski J. The pathophysiology of acquired aplastic anemia. N Engl J Med. 1997 May 8;336(19):1365-72. doi: 10.1056/NEJM199705083361906. No abstract available. PubMed 9134878 ↗
  • Mathe G, Amiel JL, Schwarzenberg L, Choay J, Trolard P, Schneider M, Hayat M, Schlumberger JR, Jasmin C. Bone marrow graft in man after conditioning by antilymphocytic serum. Br Med J. 1970 Apr 18;2(5702):131-6. doi: 10.1136/bmj.2.5702.131. PubMed 4909449 ↗
  • Stein RS, Means RT Jr, Krantz SB, Flexner JM, Greer JP. Treatment of aplastic anemia with an investigational antilymphocyte serum prepared in rabbits. Am J Med Sci. 1994 Dec;308(6):338-43. doi: 10.1097/00000441-199412000-00005. PubMed 7985721 ↗
  • Scheinberg P, Nunez O, Weinstein B, Scheinberg P, Wu CO, Young NS. Activity of alemtuzumab monotherapy in treatment-naive, relapsed, and refractory severe acquired aplastic anemia. Blood. 2012 Jan 12;119(2):345-54. doi: 10.1182/blood-2011-05-352328. Epub 2011 Nov 8. PubMed 22067384 ↗
10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Jul 21, 2021, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT00065260
Lead sponsor
National Heart, Lung, and Blood Institute (NHLBI)
Responsible party
Sponsor
First posted
Jul 21, 2003
Start date
Nov 6, 2003
Primary completion
Dec 29, 2010
Completion
Feb 5, 2016
Results posted
Mar 3, 2016
Last update
Jul 21, 2021

Study contacts

Danielle M Townsley, M.D.
principal investigator · National Heart, Lung, and Blood Institute (NHLBI)

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

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This study is completed, as verified in Jun 2021. You cannot join it, but the record below documents what was studied.

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