ADI-PEG 20 in Combination With Gemcitabine and Docetaxel for the Treatment of Soft Tissue Sarcoma, Osteosarcoma, Ewing's Sarcoma, and Small Cell Lung Cancer

-Arginine deiminase (ADI) is a recombinant protein cloned from M. hominis, produced in E. coli, and conjugated with PEG of 20,000 mw using a succinimidyl succinate linker. Thus ADI-PEG 20 is an arginine degrading enzyme, ADI, coupled to PEG.

-Gemcitabine is a nucleoside metabolic inhibitor that exhibits antitumor activity.

-Docetaxel is an antineoplastic agent belonging to the taxoid family. It is prepared by semisynthesis beginning with a precursor extracted from the renewable needle biomass of yew plants.

"* Up to 21 days prior to initiation of ADI-PEG 20 Day -1 (+/- 1 day as long as performed prior to initiation of gemcitabine.~* Tumor biopsies are mandatory for the first 20 patients amendable to biopsy enrolled at Washington University only (completed as of 05/14/2019) and for all patients enrolled to the SCLC cohort"

-Day -7 (pre-treatment), Day -1, and Days 1 and 8 of each cycle