the absence of a control group, it is not clear in many cases whether these events should be attributed to temozolomide or the patients' underlying conditions, but nausea, vomiting, fatigue, and hematologic effects appear to be clearly drug related. The most frequently occurring side effects were nausea, vomiting, headache, and fatigue. The adverse events were usually NCI Common Toxicity Criteria (CTC) Grade 1 or 2 (mild to moderate in severity) and were self-limiting, with nausea and vomiting readily controlled with antiemetics. The incidence of severe nausea and vomiting (CTC Grade 3 or 4) was 10% and 6%, respectively. Myelosuppression (thrombocytopenia and neutropenia) was the dose-limiting adverse event. It usually occurred within the first few cycles of therapy and was not cumulative.
Myelosuppression occurred late in the treatment cycle and returned to normal, on average, within 14 days of nadir counts. The median nadirs occurred at 26 days for platelets (range 21 to 40 days) and 28 days for neutrophils (range 1 to 44 days). Only 14% (22/158) of patients had a neutrophil nadir and 20% (32/158) of patients had a platelet nadir which may have delayed the start of the next cycle. Less than 10% of patients required hospitalization, blood transfusion, or discontinuation of therapy due to myelosuppression.
In clinical trial experience with 110 to 111 women and 169 to 174 men (depending on measurements), there were higher rates of Grade 4 neutropenia (ANC < 500 cells/µL) and thrombocytopenia (< 20,000 cells/µL) in women than men in the first cycle of therapy: (12% versus 5% and 9% versus 3%, respectively).
In the entire safety database for which hematologic data exist (N=932), 7% (4/61) and 9.5% (6/63) of patients over age 70 experienced Grade 4 neutropenia or thrombocytopenia in the first cycle, respectively. For patients less than or equal to age 70, 7% (62/871) and 5.5% (48/879) experienced Grade 4 neutropenia or thrombocytopenia in the first cycle, respectively. Pancytopenia, leukopenia, and anemia have also been reported.
Table 3 Adverse Events in the Anaplastic Astrocytoma Trial
in Adults (>/=5%)
No. (%) of TEMODAR Patients (N=158)
All Events Grade 3/4
Any Adverse Event 153 (97) 79 (50)
Body as a Whole
Headache 65 (41) 10 (6)
Fatigue 54 (34) 7 (4)
Asthenia 20 (13) 9 (6)
Fever 21 (13) 3 (2)
Back pain 12 (8) 4 (3)
Cardiovascular
Edema peripheral 17 (11) 1 (1)
Central and Peripheral Nervous System
Convulsions 36 (23) 8 (5)
Hemiparesis 29 (18) 10 (6)
Dizziness 19 (12) 1 (1)
Coordination abnormal 17 (11) 2 (1)
Amnesia 16 (10) 6 (4)
Insomnia 16 (10) 0
Paresthesia 15 (9) 1 ( |
