Trial Outcomes & Findings for Evaluating QTc, PK, Safety of Gemtuzumab Ozogamicin (GO) in Patients With CD33+ R/R AML (NCT NCT03727750)

NCT ID: NCT03727750

Last Updated: 2022-03-25

Results Overview

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

• Recruitment status: COMPLETED
• Study phase: PHASE4
• Target enrollment: 51 participants
• Primary outcome timeframe: Baseline, Cycle 1 Day 1: 1 Hour
• Results posted on: 2022-03-25

Participant Flow

A total 66 participants signed the informed consent form and were screened. Out of 66 participants, 15 participants were screen failed and 51 participants were enrolled into the study

Participant milestones

Measure	Gemtuzumab Ozogamicin (GO) Participants with confirmed diagnosis of refractory or relapsed cluster of differentiation (CD33)- positive Acute Myeloid Leukemia (AML) aged greater than or equal to (\>=) 18 years received three doses of Gemtuzumab Ozogamicin, 3 milligram per meter square (mg/m\^2) as intravenous (IV) infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Overall Study STARTED	51
Overall Study Safety Set	50
Overall Study COMPLETED	2
Overall Study NOT COMPLETED	49

Reasons for withdrawal

Measure	Gemtuzumab Ozogamicin (GO) Participants with confirmed diagnosis of refractory or relapsed cluster of differentiation (CD33)- positive Acute Myeloid Leukemia (AML) aged greater than or equal to (\>=) 18 years received three doses of Gemtuzumab Ozogamicin, 3 milligram per meter square (mg/m\^2) as intravenous (IV) infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Overall Study Death	45
Overall Study Withdrawal by Subject	2
Overall Study Lost to Follow-up	1
Overall Study Other	1

Baseline Characteristics

Evaluating QTc, PK, Safety of Gemtuzumab Ozogamicin (GO) in Patients With CD33+ R/R AML

Baseline characteristics by cohort

Measure	Gemtuzumab Ozogamicin (GO) n=51 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Age, Continuous	64.9 years STANDARD_DEVIATION 11.4 • n=5 Participants
Sex: Female, Male Female	20 Participants n=5 Participants
Sex: Female, Male Male	31 Participants n=5 Participants
Ethnicity (NIH/OMB) Hispanic or Latino	6 Participants n=5 Participants
Ethnicity (NIH/OMB) Not Hispanic or Latino	40 Participants n=5 Participants
Ethnicity (NIH/OMB) Unknown or Not Reported	5 Participants n=5 Participants
Race (NIH/OMB) American Indian or Alaska Native	0 Participants n=5 Participants
Race (NIH/OMB) Asian	0 Participants n=5 Participants
Race (NIH/OMB) Native Hawaiian or Other Pacific Islander	0 Participants n=5 Participants
Race (NIH/OMB) Black or African American	3 Participants n=5 Participants
Race (NIH/OMB) White	39 Participants n=5 Participants
Race (NIH/OMB) More than one race	0 Participants n=5 Participants
Race (NIH/OMB) Unknown or Not Reported	9 Participants n=5 Participants

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 1: 1 Hour

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=48 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 1: 1 Hour	4.90 milliseconds Interval 2.48 to 7.32

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 1: 2 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=46 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 1: 2 Hours	4.25 milliseconds Interval 1.66 to 6.84

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 1: 4 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=49 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 1: 4 Hours	5.10 milliseconds Interval 2.15 to 8.06

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 4: 0 Hour

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=47 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 4: 0 Hour	-2.44 milliseconds Interval -5.98 to 1.09

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 4: 2 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=46 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 4: 2 Hours	-0.45 milliseconds Interval -3.98 to 3.07

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 7: 0 Hour

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=44 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 7: 0 Hour	-1.00 milliseconds Interval -4.59 to 2.58

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 7: 2 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=45 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 7: 2 Hours	4.29 milliseconds Interval 0.88 to 7.7

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 7: 4 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=44 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 7: 4 Hours	4.19 milliseconds Interval 0.45 to 7.93

PRIMARY outcome

Timeframe: Baseline, Cycle 1 Day 7: 6 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=45 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 1 Day 7: 6 Hours	1.03 milliseconds Interval -2.88 to 4.93

PRIMARY outcome

Timeframe: Baseline, Cycle 2 Day 1: 0 Hour

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=9 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 2 Day 1: 0 Hour	4.0 milliseconds Standard Deviation 11.32

PRIMARY outcome

Timeframe: Baseline, Cycle 2 Day 1: 2 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=9 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 2 Day 1: 2 Hours	7.3 milliseconds Standard Deviation 9.12

PRIMARY outcome

Timeframe: Baseline, Cycle 2 Day 7: 0 Hour

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=9 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 2 Day 7: 0 Hour	-5.4 milliseconds Standard Deviation 7.58

PRIMARY outcome

Timeframe: Baseline, Cycle 2 Day 7: 2 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=9 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 2 Day 7: 2 Hours	-1.6 milliseconds Standard Deviation 10.69

PRIMARY outcome

Timeframe: Baseline, Cycle 2 Day 7: 6 Hours

Population: QTc analysis set included all the participants in the safety analysis set who had a baseline ECG and at least 1 post-dose ECG. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Triplicate 12-lead ECG measurements (each recording separated by approximately 2 minutes) were performed and average was calculated. QT interval was the time between the start of the Q wave and the end of the T wave in the cardiac electrical cycle. QTcF was the QT interval corrected for heart rate using Fridericia's formula: QTcF = QT divided by cube root of 60/heart rate. Change from baseline in QT interval corrected for heart rate using Fridericia's formula was reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=9 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Change From Baseline in Corrected QT Interval for Heart Rate Using Fridericia's Formula (QTcF) at Cycle 2 Day 7: 6 Hours	-8.8 milliseconds Standard Deviation 14.43

SECONDARY outcome

Timeframe: Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: Pharmacokinetic (PK) analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Clearance of a drug was measure of the rate at which the drug was metabolized or eliminated by normal biological processes.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Clearance (CL) of Gemtuzumab Ozogamicin AC-CL-184538	15.02 Liters/hour Geometric Coefficient of Variation 112
Clearance (CL) of Gemtuzumab Ozogamicin CL-184538	4246 Liters/hour Geometric Coefficient of Variation 177
Clearance (CL) of Gemtuzumab Ozogamicin Total HP67.6 Antibody	0.3212 Liters/hour Geometric Coefficient of Variation 153

SECONDARY outcome

Timeframe: Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: This outcome measure could not be estimated due to insufficient concentration-time data by non-compartmental analysis.

Volume of distribution was defined as the theoretical volume in which the total amount of drug would need to be uniformly distributed to produce the desired plasma concentration of a drug.

Outcome measures

Outcome data not reported

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1; and Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Cmax was defined as the maximum observed plasma concentration of GO. Calicheamicin (conjugated calicheamicin ac-CL-184538 and unconjugated CL-184538) analyte were used to determined the Cmax in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Maximum Observed Plasma Concentration (Cmax): AC-CL-184538 and CL-184538 Cycle 1 Day 1: AC-CL-184538	6457 picogram/milliliter Geometric Coefficient of Variation 81
Maximum Observed Plasma Concentration (Cmax): AC-CL-184538 and CL-184538 Cycle 1 Day 1: CL-184538	45.69 picogram/milliliter Geometric Coefficient of Variation 51
Maximum Observed Plasma Concentration (Cmax): AC-CL-184538 and CL-184538 Cycle 1 Day 7: AC-CL-184538	11740 picogram/milliliter Geometric Coefficient of Variation 79
Maximum Observed Plasma Concentration (Cmax): AC-CL-184538 and CL-184538 Cycle 1 Day 7: CL-184538	58.76 picogram/milliliter Geometric Coefficient of Variation 70

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1; and Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Cmax was defined as the maximum observed plasma concentration of GO. Total HP67.6 antibodies analyte was used to determined the Cmax in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Maximum Observed Plasma Concentration (Cmax): Total HP67.6 Antibody Cycle 1 Day 1: Total HP67.6 Antibody	282.1 nanogram/milliliter Geometric Coefficient of Variation 77
Maximum Observed Plasma Concentration (Cmax): Total HP67.6 Antibody Cycle 1 Day 7: Total HP67.6 Antibody	585.6 nanogram/milliliter Geometric Coefficient of Variation 105

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1; and Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Tmax = time (hours) to maximum plasma concentration (Cmax).

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Time to Reach Maximum Observed Plasma Concentration (Tmax) Cycle 1 Day 1: AC-CL-184538	2.080 hours Interval 0.933 to 5.83
Time to Reach Maximum Observed Plasma Concentration (Tmax) Cycle 1 Day 1: CL-184538	2.170 hours Interval 1.0 to 6.08
Time to Reach Maximum Observed Plasma Concentration (Tmax) Cycle 1 Day 1: Total HP67.6 Antibody	2.080 hours Interval 0.933 to 4.25
Time to Reach Maximum Observed Plasma Concentration (Tmax) Cycle 1 Day 7: AC-CL-184538	2.130 hours Interval 0.0 to 6.25
Time to Reach Maximum Observed Plasma Concentration (Tmax) Cycle 1 Day 7: CL-184538	3.920 hours Interval 1.85 to 6.1
Time to Reach Maximum Observed Plasma Concentration (Tmax) Cycle 1 Day 7: Total HP67.6 Antibody	2.170 hours Interval 1.92 to 6.4

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1; and Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUClast). Calicheamicin (conjugated calicheamicin ac-CL-184538 and unconjugated CL-184538) analytes were used to determined the AUClast in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast): AC-CL-184538 and CL-184538 Cycle 1 Day 1: AC-CL-184538	93260 picogram*hour/milliliter Geometric Coefficient of Variation 83
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast): AC-CL-184538 and CL-184538 Cycle 1 Day 1: CL-184538	99.83 picogram*hour/milliliter Geometric Coefficient of Variation 171
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast): AC-CL-184538 and CL-184538 Cycle 1 Day 7: AC-CL-184538	453900 picogram*hour/milliliter Geometric Coefficient of Variation 120
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast): AC-CL-184538 and CL-184538 Cycle 1 Day 7: CL-184538	242.0 picogram*hour/milliliter Geometric Coefficient of Variation 283

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1; and Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Area under the plasma concentration-time curve from time zero to the time of the last measurable concentration (AUClast). Total HP67.6 antibodies analyte was used to determined the AUClast in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast): Total HP67.6 Antibody Cycle 1 Day 1: Total HP67.6 Antibody	2496 nanogram*hour/milliliter Geometric Coefficient of Variation 210
Area Under the Plasma Concentration-time Profile From Time Zero to the Time of Last Quantifiable Concentration (AUClast): Total HP67.6 Antibody Cycle 1 Day 7: Total HP67.6 Antibody	14740 nanogram*hour/milliliter Geometric Coefficient of Variation 388

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Area under the plasma concentration-time curve from time zero to the time 72 hours (AUC0-72). Calicheamicin (conjugated calicheamicin ac-CL-184538 and unconjugated CL-184538) analytes were used to determined the AUC0-72 in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Area Under the Plasma Concentration-time Profile From Time Zero to Time 72 Hours (AUC0-72): AC-CL-184538 and CL-184538 AC-CL-184538	93490 picogram*hour/milliliter Geometric Coefficient of Variation 82
Area Under the Plasma Concentration-time Profile From Time Zero to Time 72 Hours (AUC0-72): AC-CL-184538 and CL-184538 CL-184538	247.8 picogram*hour/milliliter Geometric Coefficient of Variation 176

SECONDARY outcome

Timeframe: Pre dose, 1, 2, 4, 6, 24 and 72 hours post dose on Cycle 1 Day 1

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Area under the plasma concentration-time curve from time zero to the time 72 hours (AUC0-72). Total HP67.6 antibodies analyte was used to determined the AUC0-72 in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=48 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Area Under the Plasma Concentration-time Profile From Time Zero to Time 72 Hours (AUC0-72): Total HP67.6 Antibody	3797 nanogram*hour/milliliter Geometric Coefficient of Variation 135

SECONDARY outcome

Timeframe: Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Number Analyzed' = participants evaluable for this outcome measure for specified rows.

Area under the plasma concentration-time curve from time zero to the time 336 hours (AUC0-336). Calicheamicin (conjugated calicheamicin ac-CL-184538 and unconjugated CL-184538) analytes were used to determined the AUC0-336 in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Area Under the Plasma Concentration-time Profile From Time Zero to Time 336 Hours (AUC0-336): AC-CL-184538 and CL-184538 AC-CL-184538	461500 picogram*hour/milliliter Geometric Coefficient of Variation 121
Area Under the Plasma Concentration-time Profile From Time Zero to Time 336 Hours (AUC0-336): AC-CL-184538 and CL-184538 CL-184538	1639 picogram*hour/milliliter Geometric Coefficient of Variation 181

SECONDARY outcome

Timeframe: Pre dose, 2, 4, 6, 72, 192 and 336 hours post dose on Cycle 1 Day 7

Population: PK analysis set included all the participants who were treated with GO and contributed at least 1 PK sample. Here, 'Overall Number of Participants Analyzed' signifies participants evaluable for this outcome measure.

Area under the plasma concentration-time curve from time zero to the time 336 hours (AUC0-336). Total HP67.6 antibodies analyte was used to determined the AUC0-336 in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=42 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Area Under the Plasma Concentration-time Profile From Time Zero to Time 336 Hours (AUC0-336): Total HP67.6 Antibody	26820 nanogram*hour/milliliter Geometric Coefficient of Variation 131

SECONDARY outcome

Timeframe: From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months)

Population: Safety analysis set included all enrolled participants who received at least 1 dose of study medication.

An AE was any untoward medical occurrence in a participant who received investigational product without regard to possibility of causal relationship. SAE was an AE resulting in any of the following outcomes or deemed significant for any other reason: death; initial or prolonged inpatient hospitalization; life-threatening experience (immediate risk of dying); persistent or significant disability/incapacity; congenital anomaly; medically important events. A treatment emergent AE was defined as an event between first dose of study drug and up to 36 days after the last dose of study drug, that was absent before treatment, or that worsened during the treatment period relative to the pretreatment state. AEs included all serious and non-serious adverse events.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Number of Participants With Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs) TEAEs	49 Participants
Number of Participants With Treatment Emergent Adverse Events (AEs) and Serious Adverse Events (SAEs) SAEs	34 Participants

SECONDARY outcome

Timeframe: From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months)

Population: Safety analysis set included all enrolled participants who received at least 1 dose of study medication.

Laboratory parameters included hematological and coagulation parameters. These included activated partial thromboplastin time prolonged, anemia, fibrinogen decreased, hemoglobin increased, international normalized ratio increased, leukocytosis, lymphocyte count decreased, lymphocyte count increased, neutrophil count decreased, platelet count decreased, white blood cell decreased. Number of participants with hematological and coagulation abnormalities by grades (as per Common Terminology Criteria for Adverse Events (CTCAE version 4.03) were reported. Grade 1= mild; Grade 2= moderate; Grade 3= severe and Grade 4= life-threatening or disabling.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Number of Participants With Shift From Grade <=2 at Baseline to Grade 3 or 4 Post-Baseline in Clinical Laboratory Abnormalities- Hematology and Coagulation Parameters	43 Participants

SECONDARY outcome

Timeframe: From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months)

Population: Safety analysis set included all enrolled participants who received at least 1 dose of study medication.

Laboratory parameters included chemistry parameters. These included: alanine aminotransferase increased, alkaline phosphatase increased, aspartate aminotransferase increased, blood bilirubin increased, creatinine increased, hypercalcemia, hyperglycemia, hyperkalemia, hypermagnesemia, hypernatremia, hypoalbuminemia, hypocalcemia, hypoglycemia, hypokalemia, hypomagnesemia, and hyponatremia. Number of participants with chemistry test abnormalities by grades (CTCAE version 4.03) were reported. Grade 1= mild; Grade 2= moderate; Grade 3= severe and Grade 4= life-threatening or disabling.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Number of Participants With Shift From Grade <=2 at Baseline to Grade 3 or 4 Post-Baseline in Clinical Laboratory Abnormalities- Chemistry Parameters	18 Participants

SECONDARY outcome

Timeframe: From first dose of study drug up to maximum of 12 months

Population: Immunogenicity analysis set included all participants in the safety analysis set who had at least 1 immunogenicity sample with results.

Percentage of participants with treatment-induced ADA positive (post baseline-positive only) and treatment-boosted ADA positive (baseline ADA titer that was boosted to a 9-fold or higher level following drug administration) were reported in this outcome measure.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Percentage of Participants With Positive Anti-Drug Antibody (ADA) Treatment-induced ADA Positive	12.0 percentage of participants
Percentage of Participants With Positive Anti-Drug Antibody (ADA) Treatment-boosted ADA Positive	0.0 percentage of participants

SECONDARY outcome

Timeframe: From first dose of study drug up to maximum of 12 months

Population: Immunogenicity analysis set included all participants in the safety analysis set who had at least 1 immunogenicity sample with results.

Percentage of participants with either treatment-induced NAb or treatment-boosted NAb were reported.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=50 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Percentage of Participants With Positive Neutralizing Antibodies (NAb)	2.0 percentage of participants

SECONDARY outcome

Timeframe: From first dose of study drug to 36 days after last dose (maximum up to of 12 months)

Population: Full analysis set included all enrolled participants.

Percentage of participants with first dose of study drug to best overall response with CR and CRi were reported. CR was defined as the disappearance of leukemia indicated by less than (<) 5 percent (%) bone marrow blasts, absence of circulating blasts with auer rods and absence of extramedullary disease, with recovery of hematopoiesis defined by absolute neutrophil count (ANC) greater than or equal to (>=)1000 per microliter (1000/mcL) and platelets >=100,000/mcL. CRi was defined as all CR criteria except residual neutropenia; ANC <1000/mcL or thrombocytopenia and platelet count <100,000/mcL.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=51 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Percentage of Participants Who Achieved Complete Remission (CR) and Complete Remission With Incomplete Hematologic Recovery (CRi)	9.8 percentage of participants Interval 3.3 to 21.4

SECONDARY outcome

Timeframe: From the first dose of study treatment to the date of death or date of censored, whichever occurred first (maximum up to 12 months)

Population: Full analysis set included all enrolled participants.

OS was defined as the time (in months) from the start date (first dose) of study treatment to the date of death due to any cause. Participants last known to be alive were censored at date of last contact. Analysis was performed using Kaplan-Meier method.

Outcome measures

Measure	Gemtuzumab Ozogamicin (GO) n=51 Participants Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Overall Survival (OS)	2.8 months Interval 1.7 to 4.2

Adverse Events

Gemtuzumab Ozogamicin (GO)

Serious events: 34 serious events

Other events: 36 other events

Deaths: 45 deaths

Serious adverse events

Measure	Gemtuzumab Ozogamicin (GO) n=50 participants at risk Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Blood and lymphatic system disorders Febrile Neutropenia	22.0% 11/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Blood and lymphatic system disorders Thrombocytopenia	4.0% 2/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Blood and lymphatic system disorders Anaemia	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Cardiac disorders Atrial Fibrillation	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Cardiac disorders Supraventricular Tachycardia	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Eye disorders Vitreous Floaters	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Gastric Haemorrhage	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Disease Progression	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Pyrexia	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Multiple Organ Dysfunction Syndrome	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Sepsis	14.0% 7/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Pneumonia	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Atypical Pneumonia	4.0% 2/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Covid-19 Pneumonia	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Escherichia Urinary Tract Infection	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Eye Infection Fungal	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Neutropenic Sepsis	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Pneumonia Klebsiella	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Pneumonia Respiratory Syncytial Viral	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Infections and infestations Sinusitis	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Injury, poisoning and procedural complications Fall	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Injury, poisoning and procedural complications Traumatic Intracranial Haemorrhage	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Metabolism and nutrition disorders Dehydration	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Neoplasms benign, malignant and unspecified (incl cysts and polyps) Acute Myeloid Leukaemia	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Respiratory, thoracic and mediastinal disorders Respiratory Failure	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Vascular disorders Capillary Leak Syndrome	2.0% 1/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.

Other adverse events

Measure	Gemtuzumab Ozogamicin (GO) n=50 participants at risk Participants with confirmed diagnosis of refractory or relapsed CD33-positive Acute Myeloid Leukemia (AML) aged \>= 18 years received three doses of Gemtuzumab Ozogamicin, 3 mg/m\^2 as IV infusion on Days 1, 4 and 7 of Cycle 1 and 2.
Blood and lymphatic system disorders Anaemia	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Blood and lymphatic system disorders Febrile Neutropenia	18.0% 9/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Blood and lymphatic system disorders Neutropenia	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Blood and lymphatic system disorders Thrombocytopenia	18.0% 9/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Abdominal Pain Upper	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Constipation	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Diarrhoea	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Gingival Bleeding	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Nausea	16.0% 8/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Gastrointestinal disorders Vomiting	12.0% 6/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Asthenia	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Chills	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Fatigue	8.0% 4/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
General disorders Pyrexia	12.0% 6/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Injury, poisoning and procedural complications Infusion Related Reaction	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Investigations Alanine Aminotransferase Increased	8.0% 4/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Investigations Aspartate Aminotransferase Increased	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Investigations Gamma-Glutamyltransferase Increased	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Metabolism and nutrition disorders Hypokalaemia	18.0% 9/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Metabolism and nutrition disorders Hypomagnesaemia	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Nervous system disorders Headache	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Renal and urinary disorders Acute Kidney Injury	6.0% 3/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.
Respiratory, thoracic and mediastinal disorders Epistaxis	10.0% 5/50 • From first dose of study drug up to 36 days after last dose (up to a maximum of 12 months) Same event may appear as AE and serious AE, what is presented are distinct events. Event may be categorized as serious in 1 participant and as non-serious in another participant or 1 participant may have experienced both serious and non-serious event during study. Safety analysis set included all enrolled participants who received at least 1 dose of study medication.

Additional Information

Pfizer ClinicalTrials.gov Call Center

Pfizer Inc.

Phone: 1-800-718-1021

Email: ClinicalTrials.gov_Inquiries@pfizer.com

Results disclosure agreements

• Principal investigator is a sponsor employee Pfizer has the right to review disclosures, requesting a delay of less than 60 days. Investigator will postpone single center publications until after disclosure of pooled data (all sites), less than 12 months from study completion/termination at all participating sites. Investigator may not disclose previously undisclosed confidential information other than study results.
• Publication restrictions are in place

Restriction type: OTHER