Combination of rhIL-11 + G-CSF enhances platelet (PLT) and myeloid recovery following ifosfamide, carboplatin, and etoposdde (ICE) chemotherapy in children with solid tumors (ST): RML-11 is well tolerated at double the adult recommended dose

RhIL-11 has demonstrated in phase II adult trials to reduce PLT tranfusions (TX) at the recommended dose of 50 ug/kg/d.(Isaacs et al Blood 88:448a, 1996 and Tepler et al Blood 87:3607,1996) We are reporting a multi-center phase I/II trial of rhIL-11 + G-CSF following ICE (I: 1800 mg/m /d × 5d, C: 400 mg/m /d × 2d, E: 100 mg/m/d × 5d) in pédiatrie ST patients (pts). RhIL-11 + G-CSF (5u,g/kg) was administered sub-q starting on day 6 until the ANC and PLT recovered 2 IK/ mm and 2100K/mm, respectively. Twenty eight pts, median age 6 (8mos-26yrs), 12F-16M, received 25 Hg/kg (n=4), 50 ug/kg (n=14), 75 Hg/kg (n=4), and 100 ug/kg (n=6) rhIL-11. None of the 28 pts receiving rML-11 exhibited evidence of Grade III or IV toxicity attributable to rhIL-11. The percentage of pts recovering their PLT Z 100K/mm1 by day 21 during cycle 1 at rhIL-11 100 Ug/kg was 67%. These results compare favorably to previous ST pts who received identical ICE with G-CSF alone (table [median]). Cytokine ANC PLT pts PLT 2100k/mm³ # PLT Ug/kg/d aiK/mm u100K/mm by day 21 TX G-CSF (10) 21d 27d 25% 12 IL-11(100) + G(5) 17.5d 19.5d 67% 2 We conclude that although the maximum tolerated dose has not been reached in children, rhIL-11 is well tolerated at double the adult recommended dose and there appears to be an enhancement of recovery of PLT CT ï100K/mm by day 21, % pts by day 21, and decrease in PLT TX compared to historical controls with G-CSF alone.