BioAtla Investor Presentation Deck

Change from baseline in sum of target lesions Non-Squamous / PD-1 Failure 60 40 // 20 -20 -40 -60 -80 -100 bicatla % Change in Target Lesions (Best Response) Non-Squamous & PD1 Failure Comb-non-Sq Mono-non-Sq Interim data- Data cut-off of Jan 4, 2023 Graphs represent patients who have had the opportunity to be followed for 12 weeks or more % Change in Target Lesions frm Baseline *Combo patients: 5 out of 7 patients discontinued due to either AEs related to nivolumab leading to treatment interruption and withdrawal (discontinued after 1 cycle; n=3) or worsening of existing brain metastasis (n=2). 60 40 20 -20 -60 -80 -100 0 5 сл % Change in Sum of Target Lesions Non-Squamous & PD1 Failure 10 15 20 Time (Weeks) 25 30 Mono Combo* 35 40 BioAtla| Overview 20

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