#1ތކތކޓރކFކށީނނި ހކއކކޗރޓަހކރކ1 ބދށަގނޑއ ހކރރއހރއނދއނަ އނ އދގެ އދއޖހވރވ ކމއ ދހހހހހށަހދއށައވރވއދއތ ތ، މ.އއާ ނ ހރ ހހހހހހ. non Conditionally Active Biologics: Transforming Cancer Therapy Corporate Presentation January 2024 bicatla#2Important Notices & Disclaimers This presentation (the "Presentation") by BioAtla, Inc. ("we", "us", "our", "BioAtla", or the "Company") contains "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995 relating to our business, operations and financial conditions, including but not limited to statements regarding business plans and prospects and whether our clinical trials will support registration; achievement of milestones; results, conduct, progress and timing of our research and development programs and clinical trials; expectations with respect to enrollment and dosing in our clinical trials, plans and expectations regarding future data updates, clinical trials, regulatory meetings and regulatory submissions; plans to form collaborations or other strategic partnerships for selected assets; the potential regulatory approval path for our product candidates; expectations about the sufficiency of our cash and cash equivalents and plans to prioritize and focus development on selected assets and indications. 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Statements contained herein are made as of the date of this Presentation unless stated otherwise, and this Presentation shall not under any circumstances create an implication that the information contained herein is correct as of any time after such date or that the information will be updated or revisited to reflect information that subsequently becomes available or changes occurring after that date hereof. Certain information contained in this Presentation relates to or is based on statistical and other industry and market data obtained from independent industry publications and research, surveys and studies conducted by independent third parties as well as the Company's own estimates of the prevalence of certain diseases and conditions. The market data used in this Presentation involves a number of assumptions and limitations, and you are cautioned not to give undue weight to such data. Industry publications and third-party research, surveys and studies generally indicate that their information has been obtained from sources believed to be reliable, although they do not guarantee the accuracy or completeness of such information. The Company's estimates of the patient population with the potential to benefit from treatment with any product candidates the Company may develop include several key assumptions based on its industry knowledge, industry publications and third-party research, which may be based on a small sample size and may fail to accurately reflect the addressable patient population. While the Company believes that its internal assumptions are reasonable, no independent source has verified such assumptions. This Presentation may contain trademarks, trade names, or service marks belonging to other entities. The Company does not intend the use or display of other parties' trade names, trademarks or service marks to imply a relationship with, or endorsement or sponsorship of, or by these other parties. None of the Company or any of its directors, officers, employees, contractors, agents, consultants, advisors or other representatives makes any representation or warranty, express or implied, as to the accuracy or completeness of the information contained in this Presentation. bicatla BioAtla| Overview 2#3BioAtla® is a clinical stage company focused on transforming cancer therapy with Conditionally Active Biologics (CABS) Proprietary technology Broad applicability in solid tumors Increases therapeutic bicatla window Two Phase 2 CAB-ADCs, one Phase 2 CAB-CTLA-4 and one Phase 1 dual CAB-bispecific T- cell engager CAB-AXL-ADC (BA3011) advancing potentially registrational trial in sarcoma as well as potentially in other indications Prioritized pipeline Clinical readouts for multiple indications / assets through 2024 Advancing strategic collaboration discussions $141.3 million in cash and cash equivalents as of 09/30/23 Cash position sufficient into 2H 2025 BioAtla| Overview 3#4Leadership Team Jay Short, Ph.D. Chairman, CEO and Cofounder bicatla STRATAGENE DIVERSA HARNESSING THE POWER OF ENZYMES lli Bristol Myers Squibb IPSEN life Bin Zhang, M.D. Sr. VP, Clinical Development. technologies PYXIS ONCOLOGY Richard Waldron, M.B.A. Chief Financial Officer INTREXON GeneMedicine, Inc. COWEN AND COMPANY William Boyle, Ph.D. Sr. Research Fellow Anaptys Bio AMGEN salk Where cures begin. Eric Sievers, M.D. Chief Medical Officer OSeattleGenetics ZYMOGENETICS A Bristol-Myers Squibb Company Monica Sullivan Sr. VP, Intellectual Property & Contracts STRATAGENE FRED HUTCH CURES START HERE" DIVERSA BARNESSING THE POWER OF ENZYMES CapalP Sheri Lydick Chief Commercial Officer Celgenel Bristol Myers Squibb™ ALTANA Susie Melody Sr. VP, Human Resources senomyx Biogen BCG BioAtla| Overview 4#5Board of Directors and Advisors bicatla Jay Short, Ph.D. Chairman, Chief Executive Officer & Cofounder Director Scott Smith Director James Allison, Ph.D. MD Anderson Cancer Center Scientific Advisor Mary Ann Gray, Ph.D. Director Lawrence Steinman, MD Director Padmanee Sharma, MD, Ph.D. MD Anderson Cancer Center Scientific Advisor Sylvia McBrinn Director Lawrence Fong, MD Cancer Immunotherapy Program, UCSF Scientific Advisor Eddie Williams Director Susan Moran, MD, MSCE Director Michael Manyak, MD GlaxoSmithKline Scientific Advisor BioAtla| Overview 5#6Selective and targeted CAB technology widens therapeutic window, thus has the potential to enhance clinical outcomes in multiple tumor types సం bicatla BioAtla discovered that acidic pH at the cancer cell surface unveils binding sites that are shielded at normal pH of healthy cells BioAtla invented CAB technology, creating antibodies that bind only to these unveiled sites on cancer cells CAB binding region is not masked or caged and thus different from prodrugs that require irreversible enzymatic cleavage to become activated CAB antibodies have the potential for increased efficacy with improved safety relative to traditional antibodies Alkaline Healthy Cell Membrane Glycocalyx Basic pH HEALTHY CELL Intracellular Mildly Acidic pH No CAB Binding H H+ eek H+ Acidic Cancer Cell Membrane CANCER CELL Intracellular Mildly Basic pH CAB Binding 1833207 H* H+ H H H+ H H Glycocalyx Acidic pH WHENDER Chang, H.W., Frey, G., Liu, H., Xing, C., Steinman, L, Boyle, B.J., & Short, J.M. (2021) PNAS 118(9): 1-10, Suppl. 1-19. BioAtla| Overview 6#7Broad applicability of BioAtla's CAB platform across several antibody types has the potential to treat multiple solid tumors I/O Antibodies Target: CTLA-4 CTLA-4 blockade activates effector T cells, thereby enhancing anti- tumor immunity CAB-CTLA4 CAB-CTLA4 ADCs Targets: AXL, ROR2 Widely expressed in a variety of tumor types, AXL and ROR2 overexpression correlates with poor prognosis, metastasis, and drug resistance to PD-1 and EGFR therapies CAB-Tumor Cell Target bicatla ADC - antibody drug conjugate; 10 - immuno-oncology; TCE - T-cell engager Cytotoxic payload and linker Bispecific TCE Target: EpCAM & CD3 Bispecific antibodies bridge cancer cells and cytotoxic T lymphocytes, activating T cells and promoting cancer cell lysis Tumor Cell Target T Cell Target CAB-EPCAM CAB-CD3 BioAtla| Overview 7#8Focused Pipeline with Broad Applicability of Differentiated CAB Assets Designed to Deliver Near-term value CAB-ADCS CAB-I/O CAB- Bispecific TCE CAB bicatla CAB Program BA3011 Mecbotamab Vedotin BA3021 Ozuriftamab Vedotin BA3071 Evalstotug BA3182 Target AXL ROR2 CTLA-4 EpCAM x CD3 Additional programs Various Indications UPS NSCLC Melanoma SCCHN Melanoma NSCLC Carcinomas Multiple tumor types Multiple tumor types IND Enabling Pre-Clinical Phase 1 Clinical IND, investigational new drug; UPS, Undifferentiated Pleomorphic Sarcoma; NSCLC, Non-small Cell Lung Cancer; SCCHN, Squamous Cell Carcinoma of the Head and Neck Phase 2 Clinical BioAtla| Overview 8#9I/O Antibody Platform: CTLA-4 (BA3071) - Basket Trial bicatla#10CAB-CTLA4 Selectively Active in Tumor Microenvironment, thereby Reducing Immune Related Adverse Events (irAEs) Non-CAB CTLA-4 bicatla inhibitors anti-CTLA4 Severe irAEs anti-CTLA4 Normal Cell Normal Cell (alkaline) Cancer cell (acidic) ↑ Cytotoxic (CD8+) T cells ⇓T regulatory cells Minimized irAEs CAB-anti-CTLA4 Normal Cell CAB CTLA-4 Tumor selective binding CAB-anti-CTLA4 BioAtla| Overview 10#11CAB-CTLA-4 (BA3071) Effectively Reduces Clinically Relevant GI Toxicity in NHP bicatla * Vehicle Control Nivo + IPI 20mg/kg + 15mg/kg Study date 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 Cvno # wwwwwwwwww Nivo + CAB-BA3071 20mg/kg + 15mg/kg #1 #2 #3 #4 #5 #1 #1 or #2 #2 #3 #4 #5 #1 #2 #3 #4 #5 A GI Symptoms Liquid feces Non-formed feces Other Gl symptoms Nivo: 20mg/kg QW (~14.6mg/kg human dose) + Ipi or BA3071: 15mg/kg QW (~11mg/kg human dose) Once weekly for four weeks exposure to Nivo + Ipi or BA3071 NHP Nonhuman primates *Chang et al., PNAS 118 (9): 1-10, 2021 BA3071 significantly reduces Gl toxicity relative to ipilimumab analog in combination with nivo BioAtla| Overview 11#12Phase 1 CAB-CTLA-4 (BA3071) Dose Escalation Key Objectives: Define safety profile and determine Phase 2 dose and MTD Evaluate antitumor activity and immunogenicity Determine PK parameters bicatla Key Eligibility Criteria: CTLA-4 naïve Treatment refractory: melanoma non-small cell lung cancer (NSCLC) renal cell carcinoma urothelial cancer gastric cancer hepatocellular carcinoma (HCC) cervical cancer small cell lung cancer (SCLC) Combination Therapy (Q3W) Cycle 1 700 mg (~10mg/kg) 350 mg (~5mg/kg) 210 mg 70 mg 21 mg 7 mg Cycle 2+ BA3071 BA3071 +240 mg nivolumab Further dose escalation planned to 1,000 mg BioAtla| Overview 12#13Phase 1 CAB-CTLA-4 (BA3071): Demographics - Baseline Patient Characteristics Median of at least 3 prior lines of treatment bicatla Data Cut Date: 15Nov23 Age, y, mean (range) ECOG Status, n (%) 0 1 # of prior systemic therapies, n (%) 1 23 ≥4 Total (N=18) 65.5 (43-79) 10 (55.6) 8 (44.4) 5 (27.8) 2 (11.1) 4 (22.2) 7 (38.9) BioAtla| Overview 13#14Phase 1 CAB-CTLA-4 (BA3071): Demographics - Tumor Types All patients experienced failure of prior PD1 treatment Tumor Type Cervical Gastric Melanoma Uveal Cutaneous Renal cell Urothelial NSCLC SCLC Pt - Platinum; Data Cut Date: 15Nov23 bicatla Total (N=18) 1 (5.6) 4 (22.2) 5 (27.8) 3 (16.7) 2 (11.1) 4 (22.2) 1 (5.6) 2 (11.1) 1 (5.6) Prior Number of Tx 3 4-6 1-2 1-6 4 3-7 3 Prior Treatment pt, anti-VEGF, anti-PD1 anti-PD1 and pt chemotherapies anti-PD1 prior anti-PD1 and TKI pt chemotherapies, anti-PD1 and ADC pt chemotherapies, taxanes, anti-PD1, TKI, anti-VEGF pt chemotherapies, anti-PD1 BioAtla| Overview 14#15CAB-CTLA-4 (BA3071) Grade 3+ Adverse Events of Special Interest 7 mg (N=1) 0 BA3071 Q3W + nivolumab 240 mg Q3W Number of subjects with at least one Grade 3+ AESI GI Toxicity Abdominal pain Diarrhea Liver Toxicity AST increased ALP increased Pulmonary Toxicity Pneumonia Endocrine Toxicity Diabetic ketoacidosis bicatla ^Patient with diarrhea also experienced Grade 3 gastritis * 1 Pt at 350 mg dose for Phase 2 included Red text denotes immune related AES Data Cut Date: 15Nov23 AST - Aspartate aminotransferase; ALP - Alkaline phosphatase 0 0 0 0 0 0 0 0 0 0 21 mg (N=1) 0 0 0 0 0 0 0 0 0 0 0 70 mg (N=3) 2 1 1 0 2 1 2 0 0 0 0 210 mg (N=3) 0 0 0 0 0 0 0 0 0 0 0 350 mg (N=7)* 1 1 0 1 0 0 0 0 0 0 0 700 mg (N=3) 2 0 0 0 0 0 0 1 1 1 1 Total (N=18) 5 (27.8) 2 (11.1) 1 (5.6) 1 (5.6) 2 (11.1) 1 (5.6) 2 (11.1) 1 (5.6) 1 (5.6) 1 (5.6) 1 (5.6) BioAtla| Overview 15#16CAB-CTLA-4 (BA3071) Grade 3+ Adverse Events of Special Interest 7 mg (N=1) BA3071 Q3W + nivolumab 240 mg Q3W Number of subjects with at least one Grade 3+ AESI GI Toxicity Abdominal pain Diarrhea Liver Toxicity AST increased ALP increased Pulmonary Toxicity Pneumonia Endocrine Toxicity Diabetic ketoacidosis bicatla ^Patient with diarrhea also experienced Grade 3 gastritis * 1 Pt at 350 mg dose for Phase 2 included Red text denotes immune related AES 0 Data Cut Date: 15Nov23 AST - Aspartate aminotransferase; ALP - Alkaline phosphatase 0 0 0 0 0 0 0 21 mg (N=1) 0 0 0 0 0 0 0 0 Only 2 patients with immune related AEs observed among 18 treated patients 0 70 mg (N=3) 0 2 1 1 0 2 0 0 0 210 mg (N=3) 0 0 0 0 0 0 0 0 0 350 mg (N=7)* 1 0 1 0 1 0 0 0 0 700 mg (N=3) 2 0 0 0 0 0 0 1 1 1 1 Total (N=18) 5 (27.8) 2 (11.1) 1 (5.6) 1 (5.6) 2 (11.1) 1 (5.6) 2 (11.1) 1 (5.6) 1 (5.6) 1 (5.6) 1 (5.6) BioAtla| Overview 16#17Phase 1 CAB-CTLA-4 (BA3071): Confirmed Responses (n=2) and Stable Disease (n=9) Among 16 Evaluable Patients bicatla Change in Target Lesion from baseline (%) Data Cut Date: 15Nov23 100 80 60 40 20 O -20 -40 -60 -80 -100 0 5 10 15 Uveal melanoma 20 Gastro-esophageal (confirmed PR, 54.3% tumor reduction, post data cut) Cervical 25 30 Cutaneous melanoma 35 40 Time (Weeks) 45 BA3071 7mg Q3W + Nivo BA3071 21mg Q3W + Nivo BA3071 70mg Q3W + Nivo BA3071 210mg Q3W + Nivo BA3071 350mg Q3W + Nivo BA3071 700mg Q3W + Nivo Cutaneous melanoma 50 SCLC 55 60 65 70 BioAtla| Overview 17#18Phase 1 CAB-CTLA-4 (BA3071): Meaningful Clinical Benefit at 350 mg in Combination with PD1 Confirmed Partial and Complete Responses Overall Response to date Complete Response Partial Response Stable Disease Progressive Disease bicatla Data Cut Date: 15Nov23 N=5 1 1 1 2 Change in Target Lesion from baseline (%) 40- 20 -20 -40 -60 -80 -100 Uveal melanoma (PD) 5 NSCLC (PD-non-target/new lesion) 10 Time (Weeks) Uveal melanoma (SD) Gastro-esophageal (confirmed PR, post data cut) 15 20 Cervical (CR) 25 BioAtla| Overview 18#19CAB-CTLA-4 (BA3071) Confirmed Partial Response - Gastro-esophageal Cancer 63-year-old male, stage IV gastro-esophageal cancer HER2 negative, post-FOLFOX, taxane, TKI, anti-PD1 and anti-VEGFI bicatla Baseline - July 31,2023 On Treatment - October 23, 2023 L BioAtla| Overview 19#20CAB-CTLA-4 (BA3071) Confirmed Complete Response - Cervical Cancer 43-year-old female, stage IV cervical cancer HPV+16 positive, post-platinum, taxane, anti-PD1 and anti-VEGF Baseline - March 23, 2023 bicatla 16.45mm "Multiple enlarged mediastinal, paraesophageal, and right hilar lymph nodes..." On Treatment - August 9, 2023 D "No enlarged mediastinal, hilar or axillary lymph nodes are present. There is persistent resolution of previously noted enlarged mediastinal and paraesophageal lymph nodes." BioAtla| Overview 20#21CAB-CTLA-4 (BA3071) - Phase 1 Dose Titration Ongoing 3 patients dosed at 700 mg Q3W in combination with nivolumab Cancer Type Renal cell Gastro-esophageal NSCLC Age Prior Tx bicatla 78 66 76 5 4 7 Adverse Events G1 fever and chills; G2 transient hypoxia G1 fever and chills G1 fever and chills; G2 transient hypoxia No No DLT Yes (atrial fibrillation) Cycles Completed 6 2 2 Overall Response SD SD SD Disposition Ongoing DC-Subject Decision DC-AE • Renal cell patient commenced prophylactic tocilizumab cycle 4 onward, now post 6 cycles and tolerating continued therapy • Further evaluation of 700 mg and potentially 1000 mg both with prophylactic tocilizumab BioAtla| Overview 21#22CAB-CTLA-4 (BA3071) Phase 2 Mono and Combo Study Currently Underway Study designed for multiple approval paths Treatment Refractory: melanoma carcinomas Monotherapy and Combination with PD1 bicatla Treatment Naïve (1st L): melanoma NSCLC Combination with PD1 350 mg Potential higher dose 350 mg Potential higher dose ● ● Monotherapy assessment Evaluating path for potential accelerated approval Further characterize safety and efficacy Inform path to pivotal RCT for full approval BioAtla| Overview 22#23bicatla CAB-AXL-ADC Platform BA3011 Mecbotamab Vedotin: Sarcoma and NSCLC#24Potential market opportunity in undifferentiated pleomorphic sarcoma (UPS) ~15% ~55% bicatla 2nd most common Soft Tissue Sarcoma (STS) subtype¹,2 patients developing recurrent or metastatic disease ³,4 0 1 year Targeted therapies specifically approved to treat UPS Median time to metastatic/local recurrence 4,5,6 Available Treatment: 1L: Approved treatments for sarcoma ORR ~15%7 ¹Brennan MF, Antonescu CR, Moraco N, Singer S. Lessons learned from the study of 10,000 patients with soft tissue sarcoma. Ann Surg. 2014;260(3):416-21; ² Penel N, bindre J-M, Giraud A, Terrier P, Ranchere-Vince D, Collin F, et al. Presentation and outcome of frequent and rare sarcoma histologic subtypes: a study of 10,262 patients with localized visceral/soft tissue sarcoma managed in reference centers. Cancer. 2018;124(6):1179-87; ³Vodanovich DA, Spelman T, May D, Slavin J, Choong PFM. Predicting the prognosis of undifferentiated pleomorphic soft tissue sarcoma: a 20-year experience of 266 cases. ANZ J Surg. 2019;89(9):1045-1050; 4Roland CL, May CD, Watson KL, et al. Analysis of Clinical and Molecular Factors Impacting Oncologic Outcomes in Undifferentiated Pleomorphic Sarcoma. Ann Surg Oncol. 2016;23(7):2220-2228; 5Delisca GO, Mesko NW, Alamanda VK, et al. MFH and high-grade undifferentiated pleomorphic sarcoma-what's in a name?. J Surg Oncol. 2015;111(2):173-177; "Winchester D, Lehman J, Tello T, et al. Undifferentiated pleomorphic sarcoma: Factors predictive of adverse outcomes. J Am Acad Dermatol. 2018;79(5):853-859; 7Product USPIS ORR, objective response rate (best objective response as confirmed complete response or partial response) BioAtla| Overview 24#25Undifferentiated Pleomorphic Sarcoma (UPS): ORR 50%, Median PFS 10.9 months Phase 1 & Phase 2, part 1 change in target lesion and progression free survival (1.8mg/kg; n=10) % Change in Target Lesions 80 ■ 60 40 20 0 -20 -40 -60 -80 -100 O 10 Change Target Lesion From Baseline (%) 20 30 50 40 Time (Weeks) Combined Phase 1 & 2: efficacy evaluable = 10 TmPS ≥ 50% 60 70 80 90 5/10 patients achieved PRs, with an ORR of 50% and PFS rate at 3 months of 60% Responses to BA3011 treatment are durable, with DOR currently exceeding 8 months Interim results satisfied the pre-defined Go criteria of UPS cohort into part 2 of the Phase 2 study Average prior lines of systemic therapy = 3 bicatla ■ ■ Progress-Free Survival Probability 1.0 0.8 0.6 - 0.4- 0.2 0.0 T 0 1 1 T T 2 3 4 All Patients 5 Progression-free Survival Number at Risk All Patients 10 10 84 4 4 6 4 T T 7 8 Events n(%) 6 (60.0) Median (mos) (95% CI) 10.9 (1.4 - NE) T T T T 9 10 11 12 13 14 15 Months from First Dose 3 3 3 3 2 2 2 2 1 Interim data- Data cut-off of Jan 18, 2023 *Votrient package insert, accessed March 2023. **DOI: 10.1200/JCO.2019.37.15_suppl. 11015 Journal of Clinical Oncology 37, no. 15_suppl (May 20, 2019) 11015-11015. TmPS, tumor membrane percent score; ORR, objective response rate; PFS, progression free survival; DOR, duration of response. 16 PFS 3mo % (95% CI) 60.0 (18.4, 75.3) T T T T T 17 18 19 20 21 22 23 24 1 1 1 1 1 1 1 0 Phase 3 randomized study of pazopanib versus placebo in metastatic soft-tissue sarcoma ("other" cohort that included UPS), progressing despite previous chemotherapy, reported a median PFS of 4.6 months for pazopanib and 1.0 months for placebo.* Single-arm SARC028 study of pembrolizumab in advanced UPS, reported median PFS of 3.0 months** Limitations of cross trial comparison should be taken into account when comparing studies BioAtla| Overview 25#26CAB-AXL (BA3011) Phase 2, part 1 Topline Interim Analysis Results in Sarcoma Following BA3011 in remaining sarcoma subtypes Sarcoma Subtype # of Pt Leiomyosarcoma Synovial Liposarcoma Osteosarcoma Ewing sarcoma Bone Other: (Chondro/Chordo) Combo CD20 Positive Combo CD20 Negative bicatla 19 13 7 8 12 8 8/3 14 12 PFS rate 28.8% (Q2W) 10.3% (3Q4W)¹ 35.7% 62.5% 45.5% 18.8% 62.5%/66.7% 32.1% 41.7% ¹Low patient compliance PFS, progression-free survival; PR, partial response; UPS, undifferentiated pleomorphic sarcoma; NE, not evaluable Confidential Partial Response/ Complete Response 0 0 0 2 PRs 0 0 1 PR (UPS) 1 PR (LMS) 'Go' if ≥1 CR/PR or PFS rate at 3 months >40%; 'No Go' if 0 CR/PR and PFS rate at 3 months <40%; BioAtla| Overview 26#27CAB-AXL (BA3011) Promising Safety and Tolerability Profile in Sarcoma Phase 2 at the RP2D 1.8 mg/kg Q2W Characteristic Any Adverse Events (AES) Related AEs with CTCAE¹ Grade 3 or 4² Any related serious AEs² Related AEs leading to death² Related AEs leading to treatment discontinuation² bicatla Constipation Peripheral Neuropathy BA3011 (N=73) 69 (94%) 20 (27%) 5 (7%) Diarrhea 0 4 (5%) BA3011 + Opdivo (N=26) 24 (92%) 10 (39%) 5 (19%) 0 Grade 1-2 (21%) Grade 3 (1%) All Grade 1-2 (16%) 1 (4%)^ Grade 3-4 (0%) Grade 1-2 (16%) Grade 3-4 (0%) Low-grade constipation observed is consistent with baseline levels seen in advanced cancer patients ■ I I No treatment-related deaths Few treatment-related SAESs, consistent with MMAE-based toxicity, including reversible myelosuppression, transient liver enzyme elevation, metabolic disturbances Very few related AEs leading to treatment discontinuation No clinically meaningful on-target toxicity observed over background Differentiated profile due to avoiding on-target off-tumor toxicity Interim data- Data cut-off of Jan 18, 2023 1CTCAE: Common Terminology Criteria for Adverse Events. The NCI Common Terminology Criteria for Adverse Events is a descriptive terminology which is utilized for Adverse Event (AE) reporting. A grading (severity) scale is provided for each AE term. 2As assessed by the investigator. Missing responses are counted as related. §Grade 2 peripheral neuropathy; pancreatitis; ^grade 2 lleus BioAtla| Overview 27#28CAB-AXL (BA3011) Phase 2 Potentially Registrational UPS Study Design • UPS Phase 2, part 2 potentially registrational study - - Enrolling total of ~80 AXL-expressing UPS patients in Phase 2, part 2 o FDA supportive of investigating a more frequent dosing regimen (3Q4W 44% and 2Q3W 38% increased exposure over Q2W) o First 40 patients with a TmPS >=50% will be randomized 1:1 to 3Q4W or 2Q3W dosing regimen O o Additional 40 patients to be enrolled at the selected dose Primary efficacy endpoint is objective response rate (ORR) per RECIST v1.1 o Primary efficacy analysis will be based on ~60 patients treated at the selected dosing regimen Prior systemic regimens limited to ≤3 bicatla UPS = Undifferentiated Pleomorphic Sarcoma; LMS = Leiomyosarcoma BioAtla| Overview 28#29Potential market opportunity in metastatic NSCLC >540K ~75-80% bicatla people in the U.S. living with lung cancer¹ non-squamous represents majority of NSCLC patients³ ~200K 2L+ newly diagnosed patients / year (U.S.) - majority advanced / metastatic² despite advances in 1L care, majority of patients progress4 Available Treatment: 1L: Chemo + ICI 50% ORR5 2L+: SOC 14% -23% ORR6. median PFS 4.5 months6 2https://www.cancer.net/cancer-types/lung-cancer-non-small- ¹https://www.lung.org/lung-health-diseases/lung-disease-lookup/lung-cancer/resource-library/lung-cancer-fact-sheet cell/statistics, ³https://thoracickey.com/carcinomas-of-the-lung-classification-and-genetics/#F1-72, 4Wang F, Wang S and Zhou Q (2020) The Resistance Mechanisms of Lung Cancer Immunotherapy. Front. Oncol. 10:568059. doi: 10.3389/fonc.2020.568059, 5Transl Lung Cancer Res 2021;10(7):3093-3105. Cyramza package insert (accessed March 2023) 1L, first line; 2L+, second line or greater; NSCLC, non-small cell lung cancer; ORR, objective response rate (best objective response as confirmed complete response or partial response), SOC, standard of care (docetaxel alone, docetaxel + ramucirumab) BioAtla| Overview 29#30AXL expression is associated poor prognosis in metastatic NSCLC Overall Survival (%) 100- 80- 60- 40- 0 bicatla 20 P=0.014 Low AXL -High AXL 40 Months 60 80 In a cohort of 98 patients with metastatic NSCLC, OS was significantly worse for those patients with high AXL expression by IHC Wu et al., J Cancer Res and Clin Oncol, 2017 Overall survival (%) No. at risk AXL low AXL high 100- 80- 60- 40- 20- 0+ 0 30 10 Median OS (95% CI), months = AXL low Undefined AXL high = 19 (14.4-23.7) 10 29 9 20 30 Follow-up (months) 24 5 17 3 -AXL low -AXL high HR=8.51 (p=0.004) 40 10 1 50 00 Lower overall survival (OS) in patients with early stage, surgically resected lung adenocarcinoma with high levels of tissue AXL Reproduced from de Miguel-Pérez D, et al. 2019 BioAtla| Overview 30#31CAB-AXL (BA3011) - Phase 2 Non-Small Cell Lung Cancer Multicenter, Phase 2, open-label trial evaluating the efficacy and safety of BA3011 alone and in combination with nivolumab Patient disposition: Confirmed locally advanced or metastatic NSCLC ● ● ● Age ≥ 18 years ECOG performance status of 0 or 1 Treatment failure of a PD-1/L1 inhibitor or approved therapy for EGFR or ALK genomic tumor aberrations AXL+ tumor staining (TmPS ≥ 1%) *Coded by MedDRA and graded according to NCI CTCAE v5 bicatla BA3011 1.8 mg/kg Q2W, 2Q3W, 3Q4W BA3011 + nivolumab 1.8 mg/kg Q2W Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. Primary endpoint: ● ● ORR via RECIST v1.1 Incidence and severity of AEs* Secondary endpoints: DOR PFS BOR, DCR, TTR, OS ● BioAtla| Overview 31#32Phase 2 CAB-AXL (BA3011) NSQ NSCLC: Baseline Demographics / Characteristics BioAtla study enrolled a heavily pretreated 3L+ population Age, y, mean (SD) Number of prior systemic therapies, n (%) 1 2 3 >4 Received prior anti-PD-1/L1 treatment, n (%) Yes No EGFR mutation status, n (%) Wild-type Mutant Unknown or missing bicatla BA3011 monotherapy (N=23) 68.3 (8.0) 4 (17.4) 6 (26.1) 9 (39.1) 4 (17.4) 21 (91.3) 2 (8.7) 16 (69.6) 4 (17.4) 3 (13.0) Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. Data Cut Date: 30Jun23 BA3011 + nivolumab (N=17) 68.9 (8.2) 2 (11.8) 3 (17.6) 2 (11.8) 10 (58.8) 15 (88.2) 2 (11.8) 13 (76.5) 2 (11.8) 2 (11.8) Total (N=40) 68.6 (8.0) 6 (15.0) 9 (22.5) 11 (27.5) 14 (35.0) 36 (90.0) 4 (10.0) 27 (67.5) 6 (15.0) 7 (17.5) BioAtla| Overview 32#33Phase 2 CAB-AXL (BA3011) Non-Squamous NSCLC Monotherapy 1.8 mg/kg Q2W shows encouraging efficacy signals Prior PD-1/L1 treatment EGFR wild-type (N=15) Data Cut Date: 30Jun23 Best Overall Response, n (%) Confirmed Partial Response Unconfirmed Partial Response Stable Disease Progressive Disease NA (early discontinuation due to AE) Response Rate n (%) Exact 95% CI Disease Control Rate n (%) Exact 95% CI bicatla 3 (20.0) 2 (13.3) 7 (46.7) 2 (13.3) 1 (6.7) 5 (33.3) 11.8, 61.6 8 (53.3) 26.6, 78.7 Monotherapy median Duration of Response was estimated to be 4.8 months with a range of 2.3-12.1+ months* Combination therapy (n=17)*: Prior PD-1/L1 treatment (N=18) Evaluable patients (majority with 4+ prior lines of therapy) received BA3011 + nivolumab One patient experienced an ongoing complete response (CR), 2 patients experienced PR, and 8 patients experienced stable disease (SD) Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. 3 (16.7) 2 (11.1) 10 (55.6) 2 (11.1) 1 (5.6) 5 (27.8) 9.7, 53.5 10 (55.6) 30.8, 78.5 *As of November 20, 2023 BioAtla| Overview 33#34Phase 2 CAB-AXL (BA3011) NSCLC Interim Analysis BA3011 Monotherapy 1.8 mg/kg Q2W 60 : 50 40 - 30 20 10- 0 -10- -20 -30 -40 -50 -60 bicatla * * confirmed * * Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. 60 40 20 0 -20 -40 -60 0 Data Cut Date: 30Jun23 5 10 15 20 Time (Weeks) 25 30 35 40 BioAtla| Overview 34#35Phase 2 CAB-AXL (BA3011) NSCLC Interim Analysis BA3011 Monotherapy 1.8 mg/kg Q2W bicatla 02 4 6 8 10 12 14 16 18 20 22 Weeks Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. 24 Data Cut Date: 30Jun23 26 28 30 1 32 Partial Response Stable Disease Progressive Disease Ongoing response AXL TmPS = 1% Patient featured in next slide Voluntary patient withdrawal Withdrawal due to AE Scan date 34 36 38 40 42 BioAtla| Overview 35#36Radiographic response to CAB-AXL (BA3011) monotherapy March 6, 2023 - Baseline scan September 20, 2023 Lymphangitic carcinomatosis Subcarinal mass 32 Red circle on left indicates subcarinal mass, resolved on right. bicatla Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. 53 yo male with adenocarcinoma of the lung, PDL1 <1%, TP53 mutation, 3 prior lines of tx (carbo/pem/pembro, docetaxel, durva/treme/selumetinib) March 6, 2023 Baseline scan September 20, 2023 1201/157 1201/ Subcarinal mass Pleural effusion Red circle on top indicates subcarinal mass, resolved below. Note also improvement in malignant pleural effusion. BioAtla| Overview 36#37Phase 2 CAB-AXL (BA3011): Summary of Treatment Emergent Adverse Events (Non-Squamous NSCLC) bicatla TEAEs with CTCAE grade 3 or 4 Related grade 3 or 4 AEs Any serious TEAES Related SAEs TEAEs leading to treatment d/c Related AEs leading to treatment d/c TEAES leading to death Related AEs leading to death BA3011 monotherapy (n=23) 15 (65.2) 8 (34.8) 9 (39.1) 3 (13.0) 1 (4.3) 1 (4.3) Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. 0 0 Data Cut Date: 30Jun23 BA3011 + nivolumab (n=17) 8 (47.1) 3 (17.6) 5 (29.4) 1 (5.9) 1 (5.9) 1 (5.9) 1 (5.9) 0 Total (N=40) 23 (57.5) 11 (27.5) 14 (35.0) 4 (10.0) 2 (5.0) 2 (5.0) 1 (2.5) 0 BioAtla| Overview 37#38Phase 2 CAB-AXL (BA3011): Treatment Emergent Adverse Events (Non-Squamous NSCLC) Any grade (≥15% of patients) OR grade ≥3* (≥3% of patients) in the study population TEAES of any grade, n (%) 14 (35.0) 10 (25.0) 9 (22.5) 9 (22.5) 8 (20.0) 8 (20.0) 7 (17.5) 7 (17.5) 6 (15.0) 6 (15.0) 5 (12.5) Preferred term Fatigue Diarrhea Constipation Decreased appetite Anemia Nausea Peripheral neuropathy Increased AST Dyspnea Neutropenia Increased ALT *No grade 4+ TEAES among most frequent bicatla Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. Data Cut Date: 30Jun23 TEAES of grade 3, n (%) 1 (2.5) 1 (2.5) 0 1 (2.5) 2 (5.0) 0 1 (2.5) 3 (7.5) 2 (5.0) 2 (5.0) 3 (7.5) BioAtla| Overview 38#39Phase 2 CAB-AXL (BA3011) NSCLC Dose Optimization In-line with FDA Project Optimus 2Q3W dosing regimen 11 patients treated ● 4 patients have been evaluable (3 SD and 1 PD) as of 12/4; target agnostic data expected in 1H 2024 ● 3Q4W dosing regimen Suboptimal compliance observed and enrollment has been discontinued ● bicatla Benefit-Risk profile observed to date with 1.8 mg/kg Q2W supports advancing this dose in registrational studies Rotow J, Dy GK, Camidge DR. Poster presented at: International Association for the Study of Lung Cancer 2023 North America Conference on Lung Cancer; December 1-3, 2023; Chicago, IL. BioAtla| Overview 39#40CAB-AXL (BA3011) NSCLC AXL Expression in Relation to Anti-tumor Activity Considerable anti-tumor activity among patients regardless of AXL expression level bicatla % Change 40 30 20 10 -10 -20 -30 -40 -50 -60 I I 0 C C C 10 1 I I I 1 1 1 I 1 I I T 1 I Best %Change in Sum of Target Lesions BA3011 Q2W Mono 20 30 40 50 TmPS (%) 60 70 80 90 100 Anti-tumor activity seen among patients with AXL low expression level supports target agnostic development BioAtla| Overview 40#41CAB-AXL (BA3011) NSCLC Randomized Registrational Study Design Two Potentially Registrational Paths Enabled via the FDA Type C Meeting 2nd Line + Open-label; control: docetaxel Patients with NSCLC who have been previously treated with at least one prior line of therapy for metastatic disease Dual primary endpoints: Progression Free Survival and Overall Survival ● ● 3rd Line + Blinded; control: chemo monotherapy Patients with NSCLC who have been previously treated with at least two prior lines of therapy for metastatic disease Primary endpoint: Overall Survival ● ● ● bicatla BioAtla| Overview 41#42bicatla CAB-ROR2-ADC Platform BA3021 Ozuriftamab Vedotin - NSCLC, Melanoma, SCCHN#43Potential market opportunity in metastatic NSCLC >540K ~75-80% bicatla people in the U.S. living with lung cancer¹ non-squamous represents majority of NSCLC patients ³ ~200K 2L+ newly diagnosed patients / year (U.S.) - majority advanced / metastatic² despite advances in 1L care, majority of patients progress4 Available Treatment: 1L: Chemo + ICI 50% ORR5 2L+: SOC 14% -23% ORR6: median PFS 4.5 months6 ¹https://www.lung.org/lung-health-diseases/lung-disease-lookup/lung-cancer/resource-library/lung-cancer-fact-sheet 2https://www.cancer.net/cancer-types/lung-cancer-non-small- cell/statistics, ³https://thoracickey.com/carcinomas-of-the-lung-classification-and-genetics/#F1-72, 4Wang F, Wang S and Zhou Q (2020) The Resistance Mechanisms of Lung Cancer Immunotherapy. Front. Oncol. 10:568059. doi: 10.3389/fonc.2020.568059, 5Transl Lung Cancer Res 2021;10(7):3093-3105. Cyramza package insert (accessed March 2023) 1L, first line; 2L+, second line or greater; NSCLC, non-small cell lung cancer; ORR, objective response rate (best objective response as confirmed complete response or partial response), SOC, standard of care (docetaxel alone, docetaxel + ramucirumab) BioAtla| Overview 43#44Encouraging Phase 1 results with CAB-ROR2 (BA3021) in refractory patients with NSCLC Maximum % Change from Baseline in Sum of Target Lesions bicatla 30% 20% 10% 0% -10% -20% -30% -40% -50% -60% ROR2 + (**TmPS=100) 1.2mg/kg d1,8 I I I I I Suboptimal dose (1.2mg/kg 2Q3W) ROR2 - (**TmPS=0) 3mg/kg d1 Patient experienced tumor shrinkage prior to progression of metastatic bone lesions Response at Variable Dosing ROR2 + (**TmPS=45) 3.3mg/kg d1 NSCLC squamous tumor: 10mm to 0mm on first scan Note: Not Evaluable (Strong, extensive fibroblastic stromal positivity reported) Not Evaluable 1.5mg/kg d1,8 ROR2 + (**TmPS=95) 3.3mg/kg d1 I ROR2 + (**TmPS=70) 3mg/kg d1 ¶ PR **Suboptimal dose 1.2 mg/kg 2Q3W. Tumor shrinkage occurred prior to progression of metastatic bone lesions. NSCLC squamous tumor 10mm to 0mm on first scan. ■ Two out of three ROR2+ patients had a partial response following BA3021 treatment BioAtla| Overview 44#45Potential Market Opportunity in Metastatic Melanoma ~1.3MM ~50% bicatla people in the U.S. living with melanoma¹ do not respond to PD-1 therapy in 1L setting² ~100K 30-40% newly diagnosed invasive cases / year (U.S.)¹ 1L, first line; 2L+, second line or greater; ICIS - Immune checkpoint inhibitors. initial responders progress² Available Treatment 1L: ICIs 33% - 50% ORR³; (BRAF / Mek inhibitors for BRAF+) 2L+: ICIS 9% -28% ORR (mono- combo, respectively)4 ¹Clarivate, Disease Landscape and Forecast: Malignant Melanoma (2022). www.cancer.net; www.cancer.org; 2Oncology (Williston Park). 33(4):141-8. ³Keytruda USPI accessed June 2022; Opdivo USPI accessed June 2022. 4VanderWalde A, Moon J, Bellasea S, et al. Ipilimumab plus nivolumab versus ipilimumab alone in patients with metastatic or unresectable melanoma that did not respond to anti-PD-1 therapy. Presented at: 2022 AACR Annual Meeting; April 8-13, 2022; New Orleans, LA. Abstract CT013. BioAtla| Overview 45#46Phase 2 CAB-ROR2 (BA3021) in Stage IV Multi-Refractory Melanoma Promising early signals of efficacy - continuing to collect data in ongoing study Completed enrollment Q2W targeted cohort who previously progressed on PD-1/L1 therapy • As of Nov 3, eight melanoma monotherapy patients are evaluable* with reported first scan data across Phase 1 and Phase 2 ● ● ▪ We observed a total of four responses, two stable disease and two progressive disease ▪ Two responses observed in ROR2 TmPS negative patients Phase 2 initial data readout (n = ~20) expected in 1H 2024 bicatla *7 patients in Phase 2 received 1.8 mg/kg Q2W and 1 patient in Phase 1 received 3.0 mg/kg Q3W BioAtla| Overview 46#47Potential Market Opportunity in SCCHN >400K ~50% bicatla people living with head and neck cancer (U.S.)¹ with locally advanced disease develop recurrent or refractory disease² ~66K 2L+ newly diagnosed cases / year (U.S.)¹ limited effective options post IL³ Available Treatment 1L: Pembro, cetuximab, platinum 36% ORR4 2L+: ICIS 13% -16% ORR4 ¹Clarivate, Disease Landscape and Forecast: SCCHN (2022). www.cancer.net; 2Argiris A, et al. (2017) Evidence-Based Treatment Options in Recurrent and/or Metastatic Squamous Cell Carcinoma of the Head and Neck. Front. Oncol. 7:72; ³Future Oncology, Jan. 2019. Vol. 15, No. 8; 4Ketruda USPI accessed June 2022; Opdivo USPI access June 2022. SCCHN, squamous cell carcinoma of the head and neck; 1L, first line; 2L, second line; 2L+, second line or greater; ICIS - Immune checkpoint inhibitors. BioAtla| Overview 47#48Phase 1 results with CAB-ROR2 (BA3021) support advancing into Phase 2 in multiple indications ROR2+ Tumor Types NSCLC Melanoma SCCHN bicatla Results ▪ Partial response in 2 / 3 patients who previously experienced failure on PD-1 and who received Phase 2 dose or higher ▪ Complete response in 1 / 1 patient who previously experienced failure on PD-1 Clearance of pulmonary metastases followed by normalization of adenopathy Continued complete response off treatment for over 2 years ■ ■ Partial response in 1 / 1 ROR2+ refractory to four prior lines of therapy including cetuximab and PD-1 (pembrolizumab) Promising safety and tolerability profile across multiple tumor types No ROR2 ADC or small molecules in the clinic to date, suggesting CAB-ROR2-ADC is a first-in-class therapy across multiple tumor types BioAtla| Overview 48#49CAB-ROR2 (BA3021) Dosing Regimens Under Evaluation All cycles (28 days) All cycles (21 days) Cycle 1 (21 days) Cycle 2 (28 days) and subsequent cycles bicatla Source: Form 10-K Q2W 2Q3W 3Q4W Day 1 1.8 mg/kg Day 8 2.0 mg/kg 1.3 mg/kg Dose no drug 1.8 mg/kg 1.8 mg/kg 1.3 mg/kg 1.3 mg/kg Day 15 1.8 mg/kg no drug 1.3 mg/kg 1.3 mg/kg Day 22 no drug no drug BioAtla| Overview 49#50Phase 2 CAB-ROR2 (BA3021) Summary of Dosing Regimens for Clinical Studies Indication NSCLC* Melanoma Head and Neck bicatla Dose Q2W monotherapy Q2W in combo w/ nivolumab 3Q4W monotherapy Q2W monotherapy Q2W monotherapy 2Q3W monotherapy *Currently no plans to internally explore NSCLC further at this time NSCLC = non small cell lung cancer Maximum Patient # N~ 20 N~ 20 N~ 20 N~ 25 N~ 20 N~ 20 Status ✓ ✓ Not advancing; suboptimal compliance Fully enrolled Not advancing Fully enrolled BioAtla| Overview 50#51bicatla Bispecific Platform CAB-EpCAM X CAB-CD3 (BA3182) - Adenocarcinoma#52CAB-EpCAMXCAB-CD3 Bispecific T-Cell Engager (BA3182) significant opportunity for safe and effective EpCAMXCD3 bispecific EpCAM expressed on normal epithelial cells and overexpressed in a wide range of tumors (adenocarcinoma) CD3-bispecifics have demonstrated beneficial effects but hampered by dose-limiting toxicity, namely, cytokine release syndrome (CRS) 2500 Tumor volume (mm³) bicatla 2000 1500 1000 500 0 0 Tumor shrinkage Isotype x WT CD3 -EpCAM x WT CD3 ACAB EpCAM x CAB CD3 10 20 30 40 Study Days MiXeno Model with HCT116= Colorectal Cancer Cell Line 1mg/kg twice/week in mice (equivalent to 0.25mg/kg in non-human primates) 50 ● ● BA3182 exhibits efficient tumor shrinkage with superior safety profile In non-GLP and GLP tox studies in NHP, dual selection results in high selectivity ► 160-fold TI increase MTD not reached (5mg/kg highest dose studied=NOAEL) No Cytokine release observed or other EpCAM or CD3 known related toxicities Safety Profile WT-EpCAM x WT-CD3 *0.025mg/kg = 2 ill *0.05 mg/kg = 2 expired *Single Dose - non-GLP Toxicity Study WT = wild type; *from independent experiments MTD Maximum Tolerated Dose TI = Therapeutic Index CAB-EpCAM x CAB-CD3 (BA3182) *0.25mg/kg = 2 normal *1.0 mg/kg = 2 normal *2.5 mg/kg = 2 normal *2.5 mg/kg = 10 normal *5.0 mg/kg 10 normal *QW x 4 weeks - GLP Toxicity Study BioAtla| Overview = 52#53FDA cleared IND for Phase 1/2 trial design in advanced adenocarcinoma Convert to standard titration when any grade 22 AE (except AE due to the underlying disease or an extraneous cause) or a DLT Cleared Group A Accelerated Titration Cleared bicatla DL8A: 125 µg/kg DL7A: 40 µg/kg DL6A: 12.5 µg/kg ↑ DL5A: 4 µg/kg DL4A: 1.25 µg/kg DL3A: 0.4 µg/kg DL2A: 0.125 µg/kg DL1A: 0.04 µg/kg CAB-EpCAMXCAB-CD3 bispecific TCE (BA3182) • Group B Standard Titration Dose escalation using the Bayesian Optimal Interval (BOIN) design Grade 22 AE or DLT MTD or PAD DL4B DL3B ↑ DL2B ↑ DL1B: highest dose tested in Group A Group C Standard Titration with Priming If one Grade > 2 CRS is observed, initiate priming dose evaluation Grade >2 CRS Priming Dose D1 PDLXC PDL2C PDL1C 1 ↑ CIDI MTD/PAD DL2C DL1C DL1A: MABEL based starting dose 0.04 µg/kg The actual number of dose levels (cohorts) in Accelerated Titration will depend on the dose level at which the first Grade 22 AE or DLT occurs MTD: Maximum tolerated dose; PAD: Pharmacologically active dose Dosing schedule: every week (QW) initially, every two weeks (Q2W) may also be explored PDL 1C: first priming dose level; PDLxC: final priming dose level Part 1: Up to 128 patients with advanced adenocarcinoma ● ● Up to 8 patients in the accelerated titration Up to 60 in each of the 2-treatment schedules for 10 planned standard titration dose levels Part 2: Open-label study to evaluate the efficacy and safety of BA3182 in patients with advanced adenocarcinoma who have a qualifying EpCAM- expressing tumor membrane percent score (TmPS) (to be determined based on Part 1 data). BioAtla| Overview 53#54Key milestones and catalysts throughout 2024 1H BA3071: o Evaluate safety and efficacy of BA3071 at 10mg/kg and potentially, 14.2mg/kg dose levels o Initial readout Phase 2 in treatment-refractory solid tumors (~20 pts) o Demonstrate supportive data as mono- and combo- therapy BA3011: o Confirm clinical benefit in target-agnostic NSCLC patients (~30 pts) o Update UPS status bicatla 2024 BA3021: Readout final data sets in melanoma (n = ~25 pts) and SCCHN (~20 pts) BA3071: 2H Readout additional Phase 2 data in treatment-refractory solid tumors O Define pivotal path for BA3071 in treatment-refractory indications Initiate potentially registrational study with either BA3071 in a solid tumor and/or BA3011 in NSCLC Establish strategic collaboration for BA3071 and/or one CAB ADC EpCAM Phase 1 data readout; initiate Phase 2 as data support BioAtla| Overview 54#55BioAtla® is a clinical stage company focused on transforming cancer therapy with Conditionally Active Biologics (CABS) Proprietary technology Broad applicability in solid tumors Increases therapeutic bicatla window Two Phase 2 CAB-ADCs, one Phase 2 CAB-CTLA-4 and one Phase 1 dual CAB-bispecific T- cell engager CAB-AXL-ADC (BA3011) advancing potentially registrational trial in sarcoma as well as potentially in other indications Prioritized pipeline Clinical readouts for multiple indications / assets through 2024 Advancing strategic collaboration discussions $141.3 million in cash and cash equivalents as of 09/30/23 Cash position sufficient into 2H 2025 BioAtla| Overview 55