Lintuzumab-Ac225 in Older Acute Myeloid Leukemia (AML) Patients

Overview

About this study

The study is a multicenter, open label Phase I/II trial. 1. Establish the MTD of fractionated doses of Lintuzumab-Ac225 in combination with low dose cytosine arabinoside (Low Dose Ara-C, LDAC) (Phase 1 portion) 2. Determine the response rate (CR + CRp + CRi) to fractionated doses of Lintuzumab-Ac225 alone (Phase 2 portion)

Participation eligibility

Participant eligibility includes age, gender, type and stage of disease, and previous treatments or health concerns. Guidelines differ from study to study, and identify who can or cannot participate. There is no guarantee that every individual who qualifies and wants to participate in a trial will be enrolled. Contact the study team to discuss study eligibility and potential participation.

Phase 1 Major Inclusion Criteria:

  1. Untreated AML, including patients with an antecedent hematologic disorder or secondary disease. Patients with prior MDS may have received therapy with immunomodulatory agents or hypomethylating agents for this diagnosis. Patients with other prior cancer diagnoses are allowed as long as they have no measurable disease, are not undergoing active therapy, and have a life expectancy of ≥ 4 months.
  2. Patients age ≥60 years who:
    1. Are unwilling to receive intensive (e.g. 7+3) chemotherapy, or
    2. Have poor-risk prognostic factors defined as antecedent hematologic disorder, prior chemotherapy or XRT, abnormal karyotype other than t(8;21), inv16, or t(16;16), any karyotype with FLT3-ITD, or presenting WBC>100K, or
    3. Have significant comorbidities, that in the judgment of the investigator makes the subject unsuitable for standard dose induction chemotherapy (e.g. anthracycline and infusional cytarabine given as 7+3), or;
    4. Any patient age ≥ 70 years.
  3. Blast count ≥20%
  4. Greater than 25% of blasts must be CD33 positive.
  5. Adequate renal and hepatic function
  6. ECOG ≤ 3

Phase 2 Inclusion Criteria:

  1. Untreated AML, including patients with an antecedent hematologic disorder or secondary disease. Patients with prior MDS may have received therapy with immunomodulatory agents or hypomethylating agents for this diagnosis. Patients with other prior cancer diagnoses are allowed as long as they have no measurable disease, are not undergoing active therapy, and have a life expectancy of ≥ 4 months.
  2. Patients age ≥60 years who:
    1. Patients ≥60 years unfit to receive intensive (e.g., 7+3) chemotherapy who have:
      • Congestive heart failure or documented cardiomyopathy with an EF ≤50%, provided that EF ≥35% or,
      • Documented pulmonary disease with DLCO ≤65% or FEV1 ≤65%, provided that patients do not require more than 2 L of oxygen per minute or,
      • Documented liver disease with marked elevation of transaminases >3 x ULN or,
      • Serum creatinine >1.2 mg/dL
    2. Have significant comorbidities, that in the judgment of the investigator makes the subject unsuitable for standard dose induction chemotherapy (e.g., anthracycline and infusional cytarabine given as 7+3); or
    3. Any patient age ≥ 75 years.
  3. Blast count ≥ 20% (WHO criteria)
  4. Greater than 25% of blasts must be CD33 positive.
  5. Have a circulating blast count of less than 200/mm3 (control with hydroxyurea or similar agent is allowed);
  6. Creatinine < 2.0 mg/dl
  7. Estimated creatinine clearance ≥ 50ml/min
  8. Bilirubin ≤ 2.0 mg/dl; AST and ALT < 5.0 times the ULN
  9. Eastern Cooperative Oncology Group (ECOG) Performance Status ≤ 3

Exclusion Criteria:

  1. Patients with acute promyelocytic leukemia
  2. Treatment with chemotherapy or biologic therapy within 3 weeks, except for hydroxyurea, which must be discontinued prior to treatment on study
  3. Treatment with radiation within 6 weeks
  4. Active serious infections uncontrolled by antibiotics
  5. Active malignancy within 2 years of entry, except previously treated non-melanoma skin cancer, carcinoma in situ or cervical intraepithelial neoplasia, and organ confined prostate cancer with no evidence of progressive disease based on PSA levels and are not on active therapy.
  6. Clinically significant cardiac or pulmonary disease
  7. Patients with liver cirrhosis
  8. Active CNS leukemia. Patients with symptoms of CNS involvement, particularly those with M4 or M5 subtypes, should undergo lumbar puncture prior to treatment on study to exclude CNS disease. Symptoms include cranial neuropathies, other neurologic deficits, and headache.
  9. Psychiatric disorder that would preclude study participation

Participating Mayo Clinic locations

Study statuses change often. Please contact the study team for the most up-to-date information regarding possible participation.

Mayo Clinic Location Status Contact

Rochester, Minn.

Mayo Clinic principal investigator

Kebede Begna, M.D.

Closed for enrollment

Contact information:

Cancer Center Clinical Trials Referral Office

855-776-0015

More information

Publications

  • The eradication of cancer remains a vexing problem despite recent advances in our understanding of the molecular basis of neoplasia. One therapeutic approach that has demonstrated potential involves the selective targeting of radionuclides to cancer-associated cell surface antigens using monoclonal antibodies. Such radioimmunotherapy (RIT) permits the delivery of a high dose of therapeutic radiation to cancer cells, while minimizing the exposure of normal cells. Although this approach has been investigated for several decades, the cumulative advances in cancer biology, antibody engineering and radiochemistry in the past decade have markedly enhanced the ability of RIT to produce durable remissions of multiple cancer types. Read More on PubMed
  • Because alpha-particles have a shorter range and a higher linear energy transfer (LET) compared with beta-particles, targeted alpha-particle immunotherapy offers the potential for more efficient tumor cell killing while sparing surrounding normal cells. To date, clinical studies of alpha-particle immunotherapy for acute myeloid leukemia (AML) have focused on the myeloid cell surface antigen CD33 as a target using the humanized monoclonal antibody lintuzumab. An initial phase I study demonstrated the safety, feasibility, and antileukemic effects of bismuth-213 ((213)Bi)-labeled lintuzumab. In a subsequent study, (213)Bi-lintuzumab produced remissions in some patients with AML after partial cytoreduction with cytarabine, suggesting the utility of targeted alpha-particle therapy for small-volume disease. The widespread use of (213)Bi, however, is limited by its short half-life. Therefore, a second-generation construct containing actinium-225 ((225)Ac), a radiometal that generates four alpha-particle emissions, was developed. A phase I trial demonstrated that (225)Ac-lintuzumab is safe at doses of 3 μCi/kg or less and has antileukemic activity across all dose levels studied. Fractionated-dose (225)Ac-lintuzumab in combination with low-dose cytarabine (LDAC) is now under investigation for the management of older patients with untreated AML in a multicenter trial. Preclinical studies using (213)Bi- and astatine-211 ((211)At)-labeled anti-CD45 antibodies have shown that alpha-particle immunotherapy may be useful as part conditioning before hematopoietic cell transplantation. The use of novel pretargeting strategies may further improve target-to-normal organ dose ratios. Read More on PubMed
  • Alpha particle-emitting isotopes are being investigated in radioimmunotherapeutic applications because of their unparalleled cytotoxicity when targeted to cancer and their relative lack of toxicity towards untargeted normal tissue. Actinium- 225 has been developed into potent targeting drug constructs and is in clinical use against acute myelogenous leukemia. The key properties of the alpha particles generated by 225Ac are the following: i) limited range in tissue of a few cell diameters; ii) high linear energy transfer leading to dense radiation damage along each alpha track; iii) a 10 day halflife; and iv) four net alpha particles emitted per decay. Targeting 225Ac-drug constructs have potential in the treatment of cancer. Read More on PubMed

Study Results Summary

Not yet available

Supplemental Study Information

Not yet available

.
CLS-20385839

Mayo Clinic Footer