Phase II Study of Sequential Gemcitabine Followed by Docetaxel for Recurrent Ewing’s Sarcoma, Osteosarcoma, or Unresectable or Locally Recurrent Chondrosarcoma PI: Lee Helman, MD Co-PI: Shreyaskumar Patel, MD

Objectives Primary Objective:Primary Objective: –Determine Objective Response Rate (RECIST) of Gemcitabine followed by Docetaxel in OS, EWS, and Chondrosarcoma Secondary Objectives:Secondary Objectives: –Determine Time to Progression –Assess toxicity –Pharmacokinetics of gemcitabine alone and gemcitabine followed by docetaxel –Gene expression profiling, when possible

Eligibility Recurrent high grade OS, recurrent EWS, unresectable or locally recurrent unresectable chondrosarcoma Age ≥ 4 years Measurable Disease by RECIST Criteria Prior Therapy: Recovered from toxicity (< grade 2) prior therapy ≤ 2 prior retrieval chemotherapy regimens (OS, EWS) ≥ 2 weeks from myelosuppressive therapy ≥ 6 months from myeloablative chemotherapy or TBI ≥ 6 weeks local XRT, ≥ 4 months extensive XRT ≥ 72 hr from last dose of filgrastim Adequate Organ Function and Performance Status Neuropathy ≤ grade 1(chemo); ≤ grade 2 (tumor/surgery) No prior gemcitabine or taxane therapy (or allergy) No prior allogeneic stem cell transplant

Dose and Schedule Gemcitabine 675 mg/m 2 IV over 90 min Day 1, 8Gemcitabine 675 mg/m 2 IV over 90 min Day 1, 8 Docetaxel 75 mg/m 2 IV over 60 min on Day 8Docetaxel 75 mg/m 2 IV over 60 min on Day 8 –Pre-medication with dexamethasone Filgrastim : Day 9 until ANC≥ 1200/µL or Peg-filgrastim on Day 9Filgrastim : Day 9 until ANC≥ 1200/µL or Peg-filgrastim on Day 9 Cycle Duration 21 daysCycle Duration 21 days Maximum 14 cyclesMaximum 14 cycles Restaging Prior to C 1, 3, 5, 9, 13, then off studyRestaging Prior to C 1, 3, 5, 9, 13, then off study

Pharmacokinetic Sampling Cycle 1 OnlyCycle 1 Only Gemcitabine day 1 and 8: prior, 75, 85, 95, 105, 120 min.Gemcitabine day 1 and 8: prior, 75, 85, 95, 105, 120 min. Docetaxel day 8: prior, 55min, 90 min, 5 hr, 24hr.Docetaxel day 8: prior, 55min, 90 min, 5 hr, 24hr. All samples collected in THU containing heparinized tubes (Obtained from NCI)All samples collected in THU containing heparinized tubes (Obtained from NCI) PK collected on 5 patients (42%)PK collected on 5 patients (42%)

Accrual

Patient Characteristics Enrolled/Evaluable:12/11 Median Age (range): 30.5y (13-75y) Male : Female 7:4 Osteosarcoma8 Ewing’s Sarcoma 2 Chrondrosarcoma2

Toxicity Cycle 1 (n= 11) CategoryToxicityGraden% HematologicNeutropenia Gr 4 327% Platelets Gr 3 19% Gr 4 218% Hgb Gr 3 218% pRBC transfusion 218% Plt transfusion 327% InfectionFever/Neutropenia Gr 3 19% Cellulitis Gr 4 19% LymphaticEdema Gr 3 19%

Toxicity Subsequent Cycles (n=17 cycles) CategoryToxicityGraden% HematologicNeutropenia Gr 4 16% Platelets Gr 3 318% Gr 4 212% pRBC transfusion 212% Plt transfusion 212% Infection w/o Neutropenia Gr 3/4 212% PulmonaryDypsnea Gr 4 16% AllergyHypersensitivity Gr 3 212% Hepatic Transaminase Elevation 318%

Interim Conclusions Toxicity profile requires close monitoringToxicity profile requires close monitoring –Hematological -Pulmonary –Hepatic-Hypersensitivity –Serious infections with/without neutropenia Hematological toxicity in Cycle 1 resulted in dose reduction for 27% of patients (3/11)Hematological toxicity in Cycle 1 resulted in dose reduction for 27% of patients (3/11) 27 cycles of therapy have been delivered27 cycles of therapy have been delivered –5 patients required dose modifications in Cycle 2+ –3 patients removed for toxicity Response data- too earlyResponse data- too early Acquisition of PK samples is marginal (42%)Acquisition of PK samples is marginal (42%) Accrual could be betterAccrual could be better

Proposed Actions ToxicityToxicity –Verify the use of filgrastim/peg-filgrastim in all patients –Increase gemcitabine dose rate to 10 mg/m 2 /min PharmacokineticsPharmacokinetics –PK was not obtained in patients who experienced hematological toxicity AccrualAccrual –Agreements/IRB approval at additional SARC Institutions –Extend to Children’s Oncology Group Institutions –Possible International Cooperation

Gemcitabine Pharmacology Gemcitabine[dFdC] Cytidine deaminase Difluorodeoxyuridine [dFdU] Gemcitabine Triphosphate [dFdCTP] Intracellular dFdCTP inhibits DNA synthesis.Intracellular dFdCTP inhibits DNA synthesis. dFdC dose rates of > 10 mg/m 2 /min result in plasma dFdC conc > µM which saturate the rate of intracellular dFdCaccumulation.dFdC dose rates of > 10 mg/m 2 /min result in plasma dFdC conc > µM which saturate the rate of intracellular dFdCTP accumulation. The plasma pharmacokinetics of dFdC 675 mg/m 2 IV over 90 minutes (dose rate 7.5 mg/m 2 /min) have not been described.The plasma pharmacokinetics of dFdC 675 mg/m 2 IV over 90 minutes (dose rate 7.5 mg/m 2 /min) have not been described. Impact of dose-rate infusions on toxicity should be explored. [Parker et.al. ASCO 2005 Abstr 2025]Impact of dose-rate infusions on toxicity should be explored. [Parker et.al. ASCO 2005 Abstr 2025] / THU

Intracellular dFdCTP Accumulation Patel et.al. JCO 2001, 19: 3483 dFdCTP Concentration (µM)

Docetaxel Pharmacokinetics Docetaxel is metabolized by CYP3A4Docetaxel is metabolized by CYP3A4 Pharmacokinetic interactions between gemcitabine and docetaxel are unlikelyPharmacokinetic interactions between gemcitabine and docetaxel are unlikely Bruno et.al. JCO : 305Bruno et.al. JCO : 305 –Limited sampling strategy –Docetaxel exposure (AUC) was predictive of TTP in NSCLC –Docetaxel clearance was a strong independent predictor of grade 4 neutropenia and febrile neutropenia