3 . 
situation gene marking could be accomplished at 
the discretion of the patient and investigator. 
These patients eventually may develop interferon 
resistance and become candidates for cytoreductive 
chemotherapy, harvest and transplant. 
Incomplete Response /Resistance to Interferon : 
Patients who achieve major or minor responses. or 
patients who are interferon resistant (see 13,0) 
will proceed to chemotherapy cy tor eduction, 
undergo stem cell harvesting and transplant. 
4 . Timing of Cytoreductive Chemotherapy : 
At the point of maximum clinical and cytogenetic 
response interferon will be discontinued for at 
least four weeks prior to instituting aggressive 
cytoreductive chemotherapy 
5 . Cytoreductive Chemotherapy : 
Daunorubicin 120 mg/m 2 IV over 2 hours day 1 
Cytarabine 1.5 gm/m 2 I.V. continuous infusion QD x 
4 days. Steroid eye drops will be used with 
cytarabine. 
6 . G-CSF after Cytoreductive Chemotherapy: 
G-CSF 12 mcg/kg IV over 2 hours QD beginning day 5 
until the ANC exceeds 1000/mm 3 on three 
consecutive days or a planned duration of 28 days. 
May restart G-CSF if ANC falls below 500/mm 3 . 
7 . Timing of Peripheral Blood Stem Cell Harvests : 
• 
Collect PBSC starting on day when WBC > 1000 mm 3 . 
If FACS analysis show inadequate CD34+ content a 
given collection may be kept as back-up for 
further cytoreductive chemotherapy rather than 
utilized immediately. PBSC collection will be 
continued on a daily basis until an adequate 
number of nucleated cells is collected. As more 
experience is acquired it may be possible to 
define an adequate collection based on CD 34+ cell 
counts alone. 
8 . Peripheral Blood Stem Cell Collection : 
Collect PBSC as in section 7.1. 
9 . Timing of Bone Marrow Harvests for Patients in 
Recombinant DNA Research, Volume 16 
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