Table 1.

Baseline Characteristics Included in the Single-Factor Logistic Regression Analysis to Assess the Relationship to the Development of Grade 4 Toxicity and Death

Characteristic		No. of Patients (n = 100)
Age, years
Median	17
Range	≤ 1-82
Sex
Male		63
Female		37
Diagnosis
Osteosarcoma		42
Other		58
Thymidine administration
No		56
Yes		44
MTX dose, g/m2
Median	7.7
Range	0.4-12
Infusion duration, hours
Median	4
Range	1-36
Plasma MTX at 36-48 hours, μM
< 50		45
≥ 50		52
Unavailable		3
Plasma MTX prior to glucarpidase, μM
Median	17
Range	0.37-849
Serum creatinine, mg/dL
Median	3.1
Range	0.8-10.2
Diuretic use
No		19
Yes		65
Unavailable		16
Dialysis use
No		67
Yes		27
Unavailable		6
Appropriate leucovorin increase*
No		12
Yes		86
Unavailable		2
Grade 4 toxicity† prior to glucarpidase
No		81
Yes		14
Unavailable		5
Glucarpidase doses
1		62
2 every 24 hours		27
3 every 4 hours		5
Delayed dose		6
Initial plus delayed glucarpidase dose (hours after start of MTX)
≤ 96		71
> 96		27
Unavailable		2

Abbreviation: MTX, methotrexate.

^*Increased leucovorin dose to 100-1,000 mg/m² every 3 to 6 hours within 3 days of the start of the MTX infusion.

^†Grade 4 toxicity defined as mucositis, neutropenia, febrile neutropenia/sepsis, skin toxicity, diarrhea, and nausea/vomiting.