1 4 Fi g ure 2 D ose -fi n di n g: de -escalat i o n sc he ma .......................................................... 1 6 C CI Statistical Analysis Plan Study Code D419EC00001 Edition Number 4.0 Date 19Apr2023 CONFIDENTIAL AND PROPRIETARY 5of 65LIST OF ABBREVIATION S Abbreviation or special termExplanation ADA Anti-drug antibody AE Adverse event AEPI Adverse event of possible interest AESI Adverse event of special interest ALT Alanine transaminase APF Alive and progression -free APF12/18 Proportio n of patients alive and progression -free at 12 / 18 months from first dose of study treatment AST Aspartate transaminase AUC Area under the curve BMI Body mass index BoR Best objective response CAR -T Chimeric antigen receptor T -cell therapy CI Confidence interval Cmax Maximum serum concentration Cmax ss Maximum plasma concentration at steady state Cmin Minimum serum concentration Cmin ss Minimum plasma concentration at steady state COVID -19 Coronavirus Disease 2019 CPA Clinical Pharmacology Alliance CR Complete response CSP Clinical study protocol CSR Clinical study report CT Computed tomography CTCAE Common Terminology Criteria for Adverse Event CTLA -4 Cytotoxic T-lymphocy te-associated antigen 4 CV Coefficient of variation DCR Disease control rate DCO Data cut off DLT Dose -limiting toxicity DoR Duration of response Statistical Analysis Plan Study Code D419EC0000 1 Edition Number 4.0 Date 19Apr2023 CONFIDENTIAL AND PROPRIETARY 6of 65Abbreviation or special termExplanation DRC Data Review Committee ECG Electrocardiogram eCRF electronic case report form FAS Fullanaly sis set GeoSD Geometric standard deviation Gmean Geometric mean HCV Hepatitis C virus HIV Human immunodeficiency virus HLT Higher -level terms ICs Immune cells IHC Immuno histochemistry imAE Immune -mediated adverse event INRC International Neuroblastoma Response Criteria irAE Immune -related adverse event irRECIST Immune -related Response Evaluation Criteria in Solid Tumors KM Kaplan -Meier LD Longest diameter LLOQ Lower limit of quantitation MedDRA Medical Dictionary for Regulatory Activities MR Minor response MRI Magnetic resonance imaging MTD Maximum tolerated dose NA Not applicable NB Neuroblastoma NC Not calculable NCI Natio nal Cancer Institute NE Not evaluable NED No evidence of disease NK Natural killer NQ Non-quantifiable NTL Non-target lesion ORR Objective response rate Statistical Analysis Plan Study Code D419EC00001 Edition Number 4.0 Date 19Apr2023 CONFIDENTIAL AND PROPRIETARY 7of 65Abbreviation or special termExplanation OS Overall survival OS12/24 Proportio n of patients alive at 12 / 24 months from first dose of study treatment PCR Polymerase chain reaction PD Progression of disease PD-L1 Programmed cell death ligand 1 PD-L2 Programmed cell death ligand 2 PFS Progression -free survival PK Pharmacokinetics PR Partial response PT Preferred term q4w Every 4 weeks RDI Relative dose intensity RECIST Response Evaluation Criteria in Solid Tumo rs RNA Ribonucleic acid RP2D Recommended Phase II dose SAE Serious adverse event SAP Statistical Analysis Plan SARC -1 Osteosarcoma and Ewing sarcoma SARC -2 Rhabdomyosarcoma, non -rhabdomyosarcoma, and other sarcomas SARCOMA Osteosarcoma and Ewing sarcoma; soft -tissue sarcomas: Rhabdomyosarcoma, non - rhabdomyosarcoma, and other sarcomas SAS Safety analysis set SD Stable disease SoA Schedule of activities SOC System organ class STD Standard deviation STO Other solid tumors TL Target lesion TSH Thyroid stimulating ho rmone ULN Upper limit of normal Statistical A nal ysis Pla n St u d y C o de D 4 1 9 E C 0 0 0 0 1 E diti o n N u m ber 4. 0 Date 1 9 A pr 2 0 2 3 C O N FI D E N TI A L A N D P R O P RI E T A R Y 8of 6 5 A M E N D M E N T HI S T O R Y D ate Brief descri pti o n of c h a n ge 0 8J U N 2 0 2 1 T here ha ve bee n 3 pr ot oc ol versi o ns si nce t he ori gi nal S A P was create d, u p dates as f oll o ws: Secti o n 1, u p date d t o ali g n o bjecti ves wit h pr ot oc ol versi o n 5.