Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Acute myeloid leukemia (AML) is the most common adult leukemia and has historically been treated with intensive multiagent chemotherapy. In May 2000, the U.S. Food and Drug Administration approved a new agent, gemtuzumab ozogamicin (Mylotarg) to treat patients who are 60 years and older in first relapse with CD33+ AML and not considered candidates for chemotherapy. Gemtuzumab is an antibody-targeted agent that binds specifically to the CD33 antigen that is found on the surface of more than 80% of patients with AML. The agent is administered via i.v. over two hours, and premedication with acetaminophen and diphenhydramine is recommended. Side effects include fever, chills, neutropenia and thrombocytopenia, and asymptomatic hypotension. Clinical remissions have been observed with gemtuzumab, and additional trials with this new agent currently are being conducted.
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PMID:Mylotarg approved for patients with CD33+ acute myeloid leukemia. 1189 26

Gemtuzumab ozogamicin (Mylotarg) targets leukemia cells that express CD33 by means of a humanized anti-CD33 monoclonal antibody conjugated to a modified antitumor antibiotic, calicheamicin. The effects of gemtuzumab ozogamicin (given intravenously at a dose of 9 mg/m2 for 2 doses separated by 2 weeks) have been evaluated in 3 phase II studies involving patients (n = 188) with acute myeloid leukemia (AML) in first relapse. Interim analysis has revealed that 30% of patients achieved remission, characterized by < or = 5% blasts in the marrow, neutrophil count > or = 1500/microL, hemoglobin > or = 9 g/dL, and independence from red blood cell and platelet transfusion. Grade 3/4 acute toxicities included nausea or vomiting (11%); elevated serum aminotransferase enzyme (16%) and bilirubin (26%) levels; and infusion-related chills (9%), fever (6%), and hypotension (5%). As predicted with CD33-targeted therapy, most patients had neutropenia (98%) and thrombocytopenia (99%). However, the incidence of grade 3/4 bleeding events (14%) and infection rates (pneumonia, 7%; sepsis, 15%) was low. No patients were reported to have treatment-related cardiotoxicity, cerebellar toxicity, or alopecia. Veno-occlusive disease (VOD) after gemtuzumab ozogamicin treatment (but prior to other therapies) occurred in 2% of patients (4/188), and the VOD-related death rate was < 1% (1/188). Prior hematopoietic stem cell transplant may be a risk factor for VOD (P = 0.002, univariate analysis). Gemtuzumab ozogamicin is a safe and effective treatment in carefully selected patients with AML in first relapse.
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PMID:Acute and long-term toxicities associated with gemtuzumab ozogamicin (Mylotarg) therapy of acute myeloid leukemia. 1197 Jul 68

We analyzed the safety and efficacy of Mylotarg (gemtuzumab ozogamicin, an antibody-targeted chemotherapy consisting of a humanized anti-CD33 antibody linked to calicheamicin, a potent antitumor antibiotic) in the treatment of 101 patients > or =60 years of age with acute myeloid leukemia (AML) in untreated first relapse in three open-label trials. Mylotarg is administered as a 2-h intravenous infusion at 9 mg/m(2) for two doses with 14 days between doses. The overall remission rate was 28%, with complete remission (CR) in 13% of patients and complete remission with incomplete platelet recovery (CRp) in 15%. Median survival was 5.4 months for all patients and 14.5 months and 11.8 months for patients achieving CR and CRp, respectively. CD33 antigen is present on normal hematopoietic progenitor cells; thus, an expected high incidence of grade 3 or 4 neutropenia (99%) and thrombocytopenia (99%) was observed. The incidences of grade 3 or 4 elevations of bilirubin and hepatic transaminases were 24% and 15%, respectively. There was a low incidence of grade 3 or 4 mucositis (4%) and infections (27%) and no treatment-related cardiotoxicity, cerebellar toxicity, or alopecia. Mylotarg is an effective treatment for older patients with CD33-positive AML in first relapse and has acceptable toxicity.
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PMID:Antibody-targeted chemotherapy of older patients with acute myeloid leukemia in first relapse using Mylotarg (gemtuzumab ozogamicin). 1220 Jun 74

Antibody-targeted chemotherapy is a promising approach in patients with hematological malignancies. In particular, gemtuzumab ozogamicin (GO, formerly CMA-676), an anti-CD33 antibody linked to calicheamicin, has been approved for the treatment of elderly patients with acute myeloid leukemia (AML) in relapse. Nevertheless, no data are until now available concerning the possible efficacy of GO for myeloid sarcomas (MS). We treated with GO 24 AML patients, in 5 cases presenting with myeloid sarcomas of the skin or bones. The overall complete response rate was 21%. The median duration of response was 6 months. Four out of the 5 patients with myeloid sarcoma showed a regression of the masses, in two cases also obtaining a clearance of marrow blasts. The most common adverse events included thrombocytopenia, neutropenia, infections, elevation of bilirubin and hepatic transaminases. Notably, severe bleeding occurred in 5 cases (21%). VOD was documented in 1 case. We conclude that GO is effective as a single agent in AML and myeloid sarcomas. Further data are required to clarify the possible correlation between GO administration and occurrence of bleeding.
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PMID:Gemtuzumab ozogamicin for relapsed and refractory acute myeloid leukemia and myeloid sarcomas. 1522 37

Pivotal phase II studies in acute myeloblastic leukemia (AML) patients in first relapse have used gemtuzumab ozogamicin (GO) (Mylotarg) at a dose of 9 mg/m(2) on days 1 and 14. These studies showed a 26% response rate (13% complete remission (CR) and 13% CRp (complete remission with incomplete platelet recovery)) but with high degree of hematological and liver toxicities. Based on in vitro studies showing a re-expression of CD33 antigenic sites on the cell surface of blasts cells after exposure to GO, we hypothesized that fractionated doses of GO may be efficient and better tolerated. Fifty-seven patients with AML in first relapse received GO at a dose of 3 mg/m(2) on days 1, 4 and 7 for one course. Fifteen patients (26%) achieved CR and four (7%) CRp. Remission rate correlated strongly with P-glycoprotein and MRP1 activities. The median relapse-free survival was 11 months, similar for CR or CRp patients. Median duration of neutropenia < 500/microl and thrombocytopenia < 50,000/microl were, respectively, 23 and 21 days. No grade 3 or 4 liver toxicity was observed. No veno-occlusive disease occurred after GO or after hematopoietic stem cell transplantation given after GO in seven patients. Mylotarg administered in fractionated doses demonstrated an excellent efficacy/safety profile.
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PMID:High efficacy and safety profile of fractionated doses of Mylotarg as induction therapy in patients with relapsed acute myeloblastic leukemia: a prospective study of the alfa group. 1705 Dec 46

Antibody-drug conjugates (ADC) are an attractive approach for the treatment of acute myeloid leukemia and non-Hodgkin lymphomas, which in most cases, are inherently sensitive to cytotoxic agents. CD33 and CD22 are specific markers of myeloid leukemias and B-cell malignancies, respectively. These endocytic receptors are ideal for an ADC strategy because they can effectively carry the cytotoxic payload into the cell. Gemtuzumab ozogamicin (GO, Mylotarg) and inotuzumab ozogamicin consist of a derivative of calicheamicin (a potent DNA-binding cytotoxic antibiotic) linked to a humanized monoclonal IgG4 antibody directed against CD33 or CD22, respectively. Both of these ADCs have a target-mediated pharmacokinetic disposition. GO was the first drug to prove the ADC concept in the clinic, specifically in phase II studies that included substantial proportions of older patients with relapsed acute myeloid leukemia. In contrast, in phase III studies, it has thus far failed to show clinical benefit in first-line treatment in combination with standard chemotherapy. Inotuzumab ozogamicin has shown remarkable clinical activity in relapsed/refractory B-cell non-Hodgkin lymphoma, and it has started phase III evaluation. The safety profile of these ADCs includes reversible myelosuppression (especially neutropenia and thrombocytopenia), elevated hepatic transaminases, and hyperbilirubinemia. There have been postmarketing reports of hepatotoxicity, especially veno-occlusive disease, associated with GO. The incidence is ~2%, but patients who undergo hematopoietic stem cell transplantation have an increased risk. As we steadily move toward the goal of personalized medicine, these kinds of agents will provide a unique opportunity to treat selected patient subpopulations based on the expression of their specific tumor targets.
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PMID:Antibody-drug conjugates of calicheamicin derivative: gemtuzumab ozogamicin and inotuzumab ozogamicin. 2200 69

There are no data on the role of postconsolidation therapy with gemtuzumab ozogamicin (GO; Mylotarg) in children with acute myeloid leukemia (AML). The NOPHO-AML 2004 protocol studied postconsolidation randomization to GO or no further therapy. GO was administered at 5 mg/m(2) and repeated after 3 weeks. We randomized 120 patients; 59 to receive GO. Survival was analyzed on an intention-to-treat basis. The median follow-up for patients who were alive was 4.2 years. Children who received GO showed modest elevation of transaminase and bilirubin without signs of veno-occlusive disease. Severe neutropenia followed 95% and febrile neutropenia 40% of the GO courses. Only a moderate decline in platelet count and a minor decrease in hemoglobin occurred. Relapse occurred in 24 and 25 of those randomized to GO or no further therapy. The median time to relapse was 16 months versus 10 months (nonsignificant). The 5-year event-free survival and overall survival was 55% versus 51% and 74% versus 80% in those randomized to receive GO or no further therapy, respectively. Results were similar in all subgroups. In conclusion, GO therapy postconsolidation as given in this trial was well tolerated, showed a nonsignificant delay in time to relapse, but did not change the rate of relapse or survival (clinicaltrials.gov identifier NCT00476541).
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PMID:Gemtuzumab ozogamicin as postconsolidation therapy does not prevent relapse in children with AML: results from NOPHO-AML 2004. 2273 May 39

For antibody-drug conjugates (ADCs) that carry a cytotoxic drug, doses that can be administered in preclinical studies are typically limited by tolerability, leading to a narrow dose range that can be tested. For molecules with non-linear pharmacokinetics (PK), this limited dose range may be insufficient to fully characterize the PK of the ADC and limits translation to humans. Mathematical PK models are frequently used for molecule selection during preclinical drug development and for translational predictions to guide clinical study design. Here, we present a practical approach that uses limited PK and receptor occupancy (RO) data of the corresponding unconjugated antibody to predict ADC PK when conjugation does not alter the non-specific clearance or the antibody-target interaction. We used a 2-compartment model incorporating non-specific and specific (target mediated) clearances, where the latter is a function of RO, to describe the PK of anti-CD33 ADC with dose-limiting neutropenia in cynomolgus monkeys. We tested our model by comparing PK predictions based on the unconjugated antibody to observed ADC PK data that was not utilized for model development. Prospective prediction of human PK was performed by incorporating in vitro binding affinity differences between species for varying levels of CD33 target expression. Additionally, this approach was used to predict human PK of other previously tested anti-CD33 molecules with published clinical data. The findings showed that, for a cytotoxic ADC with non-linear PK and limited preclinical PK data, incorporating RO in the PK model and using data from the corresponding unconjugated antibody at higher doses allowed the identification of parameters to characterize monkey PK and enabled human PK predictions.
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PMID:Prediction of non-linear pharmacokinetics in humans of an antibody-drug conjugate (ADC) when evaluation of higher doses in animals is limited by tolerability: Case study with an anti-CD33 ADC. 2975 98