The Efficacy of Time-Sequential Administration of GO After Conventional Chemotherapy for AML

Gemtuzumab ozogamicinamicyn (GO) is an anti-cancer drug for acute myelogenous leukemia (AML), which targets CD33 positive leukemic cells. It has been approved by basis of effectiveness for refractory and relapse AML as single agent. However, the optimal method of administration is also currently under investigation. We evaluated the efficacy of time-sequential administration of GO after conventional chemotherapy as consolidation therapy for AML.

AML patients in second complete remission (CR), who received time-sequentially GO after conventional chemotherapy as consolidation, were included. The duration of second CR (+CRi), overall survival, and toxicity were examined retrospectively. To evaluate the efficacy, the duration of first CR and second CR (+CRi) was compared.

Ten patients received time-sequentially GO followed by conventional chemotherapy. Six patients were male, and four were female. Median age was 69 (62–79) years old. At the onset of AML, 7 patients had normal karyotype, 2 patients inv (16), and one patient trisomy 8, respectively. All patients were treated in lamina airflow room at the beginning of chemotherapy. All but one patient received GO 3mg/‡uat day 10 after short MEC therapy (MIT 7mg/‡u day1–3, VP16 80mg/‡u day1–5, AraC 100mg/‡u day1–5). One patient received 6 mg/‡uat day 7 after short MEC therapy. Hydrocortisone was administered before and after GO administration to prevent infusion reaction. Prevention for veno-occulusive disease was not performed. Six patients received 3 courses of treatment, one patient 2 courses, and 3 patients one course, respectively. The median duration of second CR (+CRi) and overall survival from second CR was 376 (56–2100) days and 576 (123–2099) days, respectively. In eight of ten patients, the duration of second CR was longer than first CR. All patients experienced Grade 4 toxicities of neutropenia and thrombopenia. Median period when neutrophils were less than 500/μl was 16 (9–35) days. Non-hematologic toxicities of grade 3 or more were sepsis for7 patients, febrile neutorpenia for2 patients, loss of appetite for one patient, liver dysfunction for one patients, and cardiac dysfunction for one patient. Veno-occulusive disease and infusion reaction was not experienced. Treatment-related death was not observed.

Although our experience has been limited, time-sequential administration of GO after conventional chemotherapy as consolidation therapy in second CR was very effective. Non-hematological toxicities except infections were limited. As bone marrow suppression caused by this treatment is very strong, it is very necessary to pay enough attention to infectious disease.

No relevant conflicts of interest to declare.