Phase IV, Open-label, Multicenter Study of Dasatinib in Chronic-Phase Chronic Myeloid Leukemia (CP-CML) Patients With Chronic, Low-grade Non-Hematologic Toxicity to Imatinib

Dasatinib treatment was administered and its impact on the imatinib-related Grade 1/2 adverse events was assessed. The severity of an adverse event is ranked based on grades that range from 1 to 4. Grade 1=Mild, Grade 2=Moderate, Grade 3=Severe, Grade 4= Potentially Life-threatening or disabling. Resolved, AE no longer present or resolution of imatinib-related chronic Grade 1 or Grade 2 non-hematologic AEs. Improved, AE grade reduced from Grade 2 to Grade 1. Unchanged, AE did not improve or worsen or no change in grade. Worsened, grade Increased.

The MD Anderson Symptom Inventory Chronic Myeloid Leukemia (MDASI-CML) is a validated questionnaire completed by study participants to assess symptom severity and symptom interference on daily function. These categories are divided into 5 domain summary scores: Core Symptom Severity Score, Interference Score, Symptom Severity Score, CML-Specific Symptom Severity Score, and 5 Most Severe Symptom Score. Scores were evaluated at baseline and after switching to Dasatinib on a range from 1 to 10; 1=not present/did not interfere, 10=as bad as you can imagine/interfered completely.

The EORTC QLQ-C30 questionnaire is completed by study participants to assess quality of life through nine multi-item scales: five functional scales (physical, role, cognitive, emotional and social functioning); three symptom scales (fatigue, pain and nausea/vomiting); and a global health status/QoL scale. Six single-item scales are also included (dyspnea, insomnia, appetite loss, constipation, diarrhea, and financial difficulties). All of the scales and single-item measures were evaluated at baseline and after switching to Dasatinib as an average raw score that was standardized by transformation, so that final scores were on a range in score from 0 to 100. A high score for a functional scale represents a healthy level of functioning, a high score for the global health status/QoL represents a high QoL, but a high score for a symptom scale and single-item measures represents a high level of problematic symptomatology.

SAE=a medical event that at any dose results in death, persistent or significant disability/incapacity, or drug dependency/abuse; is life-threatening, an important medical event, or a congenital anomaly/birth defect; or requires or prolongs hospitalization. AE=any new unfavorable symptom, sign, or disease or worsening of a preexisting condition that may not have a causal relationship with treatment. Treatment-related=having certain, probable, possible, or missing relationship to study drug, dasatinib.

Dasatinib treatment was administered and its impact on the Imatinib-related Grade 1/2 adverse events was assessed. The percentage of participants is based on the number that had pre-existing Imatinib-related AEs. Measure assesses the participants with reduction or improvement of at least 1 Imatinib-related Grade 1 or Grade 2 chronic AE, without a worsening of any Imatinib-related, chronic adverse events after Dasatinib treatment. The severity of an adverse event is ranked based on grades that range from 1 to 4. Grade 1=Mild, Grade 2=Moderate, Grade 3=Severe, Grade 4= Potentially Life-threatening or disabling. Improved, AE grade reduced from Grade 2 to Grade 1. Worsened, Grade Increased. Confidence interval from Clopper-Pearson method.

Molecular responses were assessed at 6 and 12 months after switching to dasatinib to determine if these baseline responses could be maintained. MR4.5, the number of treated participants with BCR-ABL transcripts ≤ 0.0032% (IS) at 6 and 12 months from the date of dasatinib initiation; MMR, Major Molecular Response = 3-log reduction in BCR-ABL gene transcripts from a standardized baseline.