Kymera Investor Presentation Deck

Upregulation of Plasma GDF-15 Shows MDM2 Target Engagement by KT-253 at Dose Levels 1 and 2 GDF-15 is Downstream Biomarker of p53 Upregulation Following MDM2 Degradation P53 Stabilization KYMERA p53 Blood MDM2 KT-253 p53 KIAD MDM2 Degradation ©2023 KYMERA THERAPEUTICS, INC. Upregulation of p53 Targets Genes GDF-15- ELISA Cycle 1 Plasma Exposure and Fold-Change in GDF-15 Levels (Mean ± SEM) Dose Level DL1: 0.05 mg/kg (n = 3) DL2: 0.10 mg/kg (n = 4) Plasma GDF-15 levels (Fold Change Over Pre-dose Baseline) 25 20 15 *Max fold increase over pre-dose baseline up to D4 post-infusion; **n=3 10 AUC (ng.h/mL) 5 353 ± 236 D1 609 ± 67.3 Cmax (ng/ml) 180 ± 116 Kinetics of Plasma GDF-15 Upregulation in Subject on DL1 Cycle 1 387 ± 24.0 Max Fold Increase in Plasma GDF-15* Pre-dose baseline 10-fold 4.7 30-fold ± 19** D4 D2 D1 Time Points: Oh, 2h, 3h, 7h from Start of Infusion D8 PAGE 38

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