We conducted a clinical trial to assess the feasibility and efficacy of CD33-directed chimeric antigen receptor-modified T cells (CART-33) for the treatment of refractory acute myeloid leukemia (AML).
Treatment with hypomethylating agent therapy might enhance anti-CD33 monoclonal antibody-mediated cytotoxicity against acute myeloid leukemia (AML) blasts through epigenetic effects on Syk and SHP-1 expression.
We evaluated gemtuzumab ozogamicin (CD33-targeted drug) used on a compassionate basis in patients diagnosed from 1995 until 2014 within Acute Myeloid Leukemia Berlin-Frankfurt-Münster studies, and identified 76 patients (<18 years) with highly-advanced and pre-treated AML [refractory <i>de novo</i> acute myeloid leukemia (n=10), <i>de novo</i> AML refractory to relapse (1<sup>st</sup> early: n=41; 1<sup>st</sup> late: n=10; 2<sup>nd</sup> or more: n=10), and secondary AML (n=5)].
Thus, this study confirmed the prognostic value of age and cytogenetic risk group and defined CD33 as a novel factor of independent prognostic importance in adult de novo AML.
CD33, CD96 and Death Associated Protein Kinase (DAPK) Expression Are Associated with the Survival Rate and/or Response to the Chemotherapy in the Patients with Acute Myeloid Leukemia (AML).
Here we provide 'proof of concept' for retargeting of UniCAR T cells to CD33- and/or CD123-positive acute myeloid leukemia blasts in vitro and in vivo.
Taken singly, the sensitivity of these markers for AML with t(8;21) ranged between 39 and 100% with CD34+ having the highest and CD33- having the lowest and the positive predictive values (PPV) ranged between 5 and 21% with CD19+ having the highest and HLA-DR+ having the lowest.
To address whether multidrug resistance protein (MRP) affects GO susceptibility, we characterized Pgp, MRP1, and MRP2 expression in CD33+ cell lines and CD33+ AML samples and analyzed the effect of the Pgp inhibitor cyclosporine (CSA) and the MRP inhibitor MK-571 on GO-induced cytotoxicity.
Gemtuzumab ozogamicin (Mylotarg; Pfizer, New York, NY) was the first antibody-drug conjugate to be approved for CD33-positive acute myeloid leukemia (AML).
Specifically, c-MYB (P </= 0.04) was significantly increased in ALL in the total fraction, whilst HOXA9 (P </= 0.19) and cystatin c (P </= 0.01) were increased in AML in the CD34(+) and CD34(-) fractions, respectively. c-MYB, hSNF2, RBAP48, HKRT-1, LYN, CD33, Adipsin and HOXA9 were increased in AML compared with remission AML, indicating an ability to determine disease activity.
We hypothesized that a leukemia-specific antigen could be created by deleting CD33 from normal hematopoietic stem and progenitor cells (HSPCs), thereby generating a hematopoietic system resistant to CD33-targeted therapy and enabling specific targeting of AML with CAR T cells.
To investigate the relationships between genetic variation and response to treatment in acute myeloid leukemia (AML), we genotyped 1931 variants on DMET genes in 94 CD33-positive AML patients enrolled in a phase III multicenter clinical trial combining Gemtuzumab-Ozogamicin (GO) with Fludarabine-Cytarabine-Idarubicin (FLAI) regimen, with the DMET Plus platform.
The most common (>30%) side effects of Mylotarg when used together with daunorubicin and cytarabine are hemorrhage and infection.The full indication is as follows: "Mylotarg is indicated for combination therapy with daunorubicin (DNR) and cytarabine (AraC) for the treatment of patients age 15 years and above with previously untreated, de novo CD33-positive acute myeloid leukemia (AML), except acute promyelocytic leukemia (APL).
Polo-like kinase inhibitor volasertib marginally enhances the efficacy of the novel Fc-engineered anti-CD33 antibody BI 836858 in acute myeloid leukemia.
However, outside of HSCT, only the anti-CD33 antibody drug conjugate gemtuzumab ozogamicin is currently approved as an antibody-targeted therapy for AML.
The therapeutic landscape is rapidly changing, with eight new drugs approved by the Food and Drug Administration within the last 2 years, including midostaurin and gilteritinib for FLT3 mutant newly diagnosed and relapsed/refractory (R/R) acute myeloid leukemia (AML), respectively; CPX-351 (liposomal cytarabine and daunorubicin) for therapy-related AML and AML with myelodysplasia-related changes; gemtuzumab ozogamicin (anti-CD33 monoclonal antibody conjugated with calicheamicin) for newly diagnosed and R/R CD33-positive AML; enasidenib and ivosidenib for IDH2 and IDH1 mutant R/R AML, respectively.
These data therefore demonstrate the potential of using immunogenic HLA-A2.1-specific CD33 peptides in developing a cellular immunotherapy for the treatment of AML patients.
CD33 targeting with HCT consolidation may be an important therapeutic strategy in high-riskFLT3/ITD AML and its efficacy and associated toxicity warrant further investigation.
We demonstrate that CLL-1 shares similar prevalence and trafficking properties that make CD33 an excellent ADC target for AML, but lacks expression on hematopoietic stem cells that hampers current CD33-targeted ADCs.