ozuriftamab vedotin (BA3021) / BioAtla - LARVOL DELTA

CRI-CCTG-0003/IND.240: Immunotherapy Platform Study in Platinum Resistant High Grade Serous Ovarian Cancer (clinicaltrials.gov) - P2 | N=60 | Recruiting | Sponsor: Canadian Cancer Trials Group | Trial primary completion date: Jun 2026 ➔ Dec 2026

Platinum resistant • Trial primary completion date • High Grade Serous Ovarian Cancer • Oncology • Ovarian Cancer • Solid Tumor

CRI-CCTG-0003/IND.240 an immunotherapy platform study in platinum-resistant high grade serous ovarian cancer (IPROC): Sub-studies A and B: Durvalumab (D) + mecbotamab vedotin (BA3011) or ozuriftamab vedotin (BA3021). (PubMed, Cancer Treat Res Commun) - "Durvalumab combined with neither BA3011 nor BA3021 demonstrated sufficient efficacy to proceed to second stage accrual. No new safety signals were identified. We showed the feasibility of collecting and analyzing tissue in this platform study."

IO biomarker • Journal • Platinum resistant • High Grade Serous Ovarian Cancer • Oncology • Ovarian Cancer • Solid Tumor • AXL • ROR2

Corporate Updates (GlobeNewswire) - "On March 2, 2026, the Company announced that its Board of Directors initiated a formal process to explore and evaluate strategic options to maximize shareholder value, including the sale of preclinical and clinical assets, licensing transactions, strategic partnerships or other corporate transactions. The Company engaged Tungsten Advisors as the Company’s exclusive strategic financial advisor to assist with this process. There can be no assurance that this process will result in any agreements or transactions."

Commercial • Solid Tumor

…The Company is re-evaluating the timing and scope of its clinical development programs… (GlobeNewswire) - "...including the appropriate timeline and pacing of additional enrollment in the Phase 1 study of BA3182, as well as the timeline to commence a Phase 3 Study for ozuriftamab vedotin (Oz-V) (CAB-ROR2-ADC) in 2L+ oropharyngeal squamous cell carcinoma (OPSCC). While the Company remains focused on conducting the ongoing Phase 1 study and is committed to its clinical development programs, there can be no assurances that clinical development of its programs will not be limited or delayed pending the outcome of the strategic process."

Clinical • Oropharyngeal Cancer • Squamous Cell Carcinoma

Phase 2 Trial of Ozuriftamab Vedotin (Oz-V), a conditionally binding ROR2-targeting ADC, in Patients with Treatment Refractory HPV+ Oropharyngeal Squamous Cell Carcinoma (OPSCC) (MHNCS 2026) - "Treatment refractory HPV+ OPSCC pts who received Oz-V achieved a 45% objective response rate associated with a manageable safety profile. These findings support further evaluation in a randomized Phase 3 trial comparing Oz-V to investigator's choice among patients with OPSCC who previously received anti-PD1 and platinum agents."

Clinical • IO biomarker • P2 data • Head and Neck Cancer • Oncology • Oropharyngeal Cancer • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck • ROR2

BioAtla and GATC Health Announce a $40 Million Special Purpose Vehicle (SPV) Transaction to Advance Ozuriftamab Vedotin (Oz-V) into a Registrational Trial for 2L+ Oropharyngeal Squamous Cell Carcinoma (OPSCC) (GlobeNewswire) - "BioAtla will receive an initial $5 million for general operating and Phase 3 clinical trial expenses to advance Oz-V in 2L+ OPSCC with the remaining $35 million anticipated to close in Q1 2026. BioAtla to retain 65% ownership of Oz-V across all solid tumor indications after completion of the SPV transaction. BioAtla will lead Phase 3 trial execution for Oz-V in OPSCC through data readout for potential accelerated approval and enrollment anticipated to begin early 2026."

Financing • New P3 trial • Oropharyngeal Cancer • Squamous Cell Carcinoma

Key Developments, Operational Updates and Upcoming Milestones (GlobeNewswire) - "Continue preparations for initiation of the Oz-V Phase 3 study in 2L+ OPSCC; on track to advance with a strategic partner in early 2026."

New P3 trial • Oropharyngeal Cancer • Squamous Cell Carcinoma

TARGETING HPV E6/E7 UPREGULATION OF THE TRANSMEMBRANE RECEPTOR TYROSINE KINASE ROR2 WITH THE ADC OZURIFTAMAB VEDOTIN IN PATIENTS WITH ADVANCED HPV+ OROPHARYNGEAL SQUAMOUS CELL CARCINOMA (IPVC 2025) - "Oz-V, an ADC targeting the ROR2 cell surface antigen that is overexpressed in HPV+ cancers achieved promising anti-tumor activity among patients with heavily pretreated HPV+ OPSCC. Oz-V was well-tolerated, toxicity was readily manageable, and a prospective Phase 3 study for advanced HPV+ OPSCC is actively planned. Use of an ADC to selectively ablate ROR2-expressing cells represents an important new, first-in-class therapeutic modality for patients with HPV+ cancers POSTERS ON BOARDS ABSTRACTS"

Clinical • Late-breaking abstract • Metastases • Anemia • Fatigue • Head and Neck Cancer • Oncology • Oropharyngeal Cancer • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck • ROR2

Identification of novel ROR2 interaction partners required for its pro-migratory signalling in breast cancer (DGHO 2025) - "Functional studies included treatment with the monoclonal ROR2 antibody Ozuriftamab and/or its antibody-drug conjugate Ozuriftamab-Vedotin... This study identifies ROR2 as a novel tumor antigen overexpressed in TNBC. Its restricted expression in normal tissue and its functional role in regulating tumor cell migration highlight its potential as a therapeutic target-particularly for delivering cytotoxic agents and inhibiting tumor dissemination in aggressive BC subtypes such as TNBC."

Breast Cancer • Oncology • Solid Tumor • Triple Negative Breast Cancer • ANXA3 • LAD1 • LMNB1 • ROR2

BA3021-002: A Phase 2 Open Label Study of BA3021 in Patients With Recurrent or Metastatic Squamous Cell Carcinoma of the Head and Neck (clinicaltrials.gov) - P2 | N=42 | Completed | Sponsor: BioAtla, Inc. | N=290 ➔ 42 | Trial completion date: Dec 2026 ➔ Sep 2025 | Trial primary completion date: Dec 2026 ➔ Sep 2025 | Recruiting ➔ Completed

Enrollment change • Trial completion • Trial completion date • Trial primary completion date • Head and Neck Cancer • Oncology • Solid Tumor • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck

BioAtla Presents Compelling Mechanistic Rationale for Targeting ROR2 with Ozuriftamab Vedotin (Oz-V) in Oropharyngeal Squamous Cell Carcinoma (OPSCC) at the Annual Conference of the International Papillomavirus Society (GlobeNewswire) - "The poster will provide a deeper molecular review of Oz-V, CAB-ROR2-ADC, a more detailed mechanistic discussion regarding the relationship between ROR2 expression and HPV infection and will highlight clinical data previously presented at medical congresses."

Clinical data • Oropharyngeal Cancer • Squamous Cell Carcinoma

CRI-CCTG-0003/IND.240: Immunotherapy Platform Study in Platinum Resistant High Grade Serous Ovarian Cancer (clinicaltrials.gov) - P2 | N=60 | Recruiting | Sponsor: Canadian Cancer Trials Group | Trial completion date: Dec 2025 ➔ Dec 2026 | Trial primary completion date: Jun 2025 ➔ Jun 2026

Platinum resistant • Trial completion date • Trial primary completion date • High Grade Serous Ovarian Cancer • Oncology • Ovarian Cancer • Solid Tumor

BioAtla Announces Regulatory Update on Clinical Development Plan for Ozuriftamab Vedotin in Oropharyngeal Squamous Cell Carcinoma (OPSCC) Following Productive Type B (End of Phase 2) Meeting with FDA (GlobeNewswire) - "Company continues preparations for enabling initiation of the Phase 3 study with the goal of advancing the study with a strategic partner early next year...Outcomes from the FDA Type B Meeting: Pivotal Trial Design: For full approval, approximately 300 OPSCC patients prospectively randomized and stratified, one to one between two open label treatment arms...Patients randomized to the investigational arm will receive 1.8 mg/kg every other week; Investigator’s Choice (IC) control arm: Patients randomized to the control arm will receive either cetuximab, docetaxel, or methotrexate monotherapy....Full Approval Endpoint: Statistically significant improvement of OS."

FDA event • New P3 trial • Oropharyngeal Cancer • Squamous Cell Carcinoma

BioAtla Reports Second Quarter 2025 Financial Results and Highlights Recent Progress (BioAtla Press Release) - "Phase 1/2 dose-escalation for conditionally binding BA3182 (CAB-EpCAM x CAB-CD3 TCE) (NCT05808634) in heavily pretreated patients with unresectable or metastatic adenocarcinoma: Phase 1 dose-escalation ongoing and on track for data readout 2H 2025....Cohort expansion data readout anticipated 1H 2026. ozuriftamab vedotin (Oz-V): Planned meeting with the FDA for guidance on proposed Phase 3 study in treatment-refractory, metastatic HPV+ OPSCC in 3Q 2025."

P1 data • Oncology

First report of ROR2 directed therapy with a conditionally active antibody drug conjugate in advanced melanoma. (ASCO 2025) - P1/2 | "Ozuriftamab vedotin showed early promising antitumor activity in this first report describing ROR2 directed treatment in refractory advanced cutaneous and uveal melanoma. Efficacy and Safety of Ozuriftamab Vedotin.*Patient has not developed progressive disease since starting treatment."

Metastases • Eye Cancer • Melanoma • Neutropenia • Oncology • Pain • Solid Tumor • Uveal Melanoma • ROR2

Phase 2 trial of ozuriftamab vedotin (BA3021), a conditionally binding ROR2-ADC, in patients with heavily pretreated squamous cell carcinoma of the head and neck. (ASCO 2025) - P1/2 | "Pts treated with ozuriftamab vedotin achieved a high rate of disease control with acceptable tolerability. Shows promising efficacy, including in pts refractory to anti-PD1 and warrants further evaluation in SCCHN."

Clinical • IO biomarker • P2 data • Anemia • Cardiovascular • Fatigue • Head and Neck Cancer • Heart Failure • Hematological Disorders • Oncology • Pain • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck • ROR2

BioAtla Presents Phase 2 Ozuriftamab Vedotin (Oz-V) Clinical Trial Data Demonstrating Compelling Antitumor Activity in HPV-Associated Oropharyngeal Squamous Cell Carcinoma (HPV+ OPSCC) at the 1.8 mg/kg Q2W dosing regimen (The Manila Times) - P1/2 | N=132 | NCT03504488 | Sponsor: BioAtla, Inc. | "Plan to finalize Phase 3 trial design in 2L+ HPV+ OPSCC with the U.S. Food and Drug Administration...The poster will be presented today at the 2025 American Society of Clinical Oncology...In the Phase 2 clinical trial, patients with heavily pretreated squamous cell carcinoma of the head and neck (SCCHN) received 1.8 mg/kg of Oz-V given in two schedules....For the efficacy analysis, 22 pts had HPV+ OPSCC (as of May 14, 2025); safety data presented (as of April 13, 2025) were based on the full dataset (n=40); In HPV+ OPSCC pts, Oz-V demonstrated compelling antitumor activity in patients receiving 1.8 mg/kg Q2W: ORR 45% (5/11), 27% (3/11) confirmed, DCR 100% (11/11), continuing follow-up; Median duration of response 9.9 months, median progression-free survival 4.7 months, and median overall survival 11.6 months and ongoing."

New P3 trial • P2 data • Oropharyngeal Cancer • Squamous Cell Carcinoma • Squamous Cell Carcinoma of Head and Neck

BioAtla Reports First Quarter 2025 Financial Results and Highlights Recent Progress (GlobeNewswire) - "Research and development (R&D) expenses were $12.4 million for the quarter ended March 31, 2025 compared to $18.9 million for the same quarter in 2024. The decrease of $6.5 million was primarily due to lower clinical development expenses in 2025 for our Phase 2 trials for mecbotamab vedotin, ozuriftamab vedotin and evalstotug as we complete trials for certain indications."

Commercial • Non Small Cell Lung Cancer • Squamous Cell Carcinoma of Head and Neck

BioAtla Announces Upcoming Poster Presentation at the 2025 American Society of Clinical Oncology (ASCO) Annual Meeting (GlobeNewswire) - "BioAtla...announced a poster presentation at the upcoming 2025 American Society of Clinical Oncology (ASCO) Annual Meeting....Title: Phase 2 trial of ozuriftamab vedotin (BA3021), a conditionally binding ROR2-ADC, in patients with heavily pretreated squamous cell carcinoma of the head and neck; Abstract Number: 6048."

P2 data • Squamous Cell Carcinoma of Head and Neck

Preclinical development of ozuriftamab vedotin (BA3021), a novel ROR2-specific conditionally active biologic antibody-drug conjugate. (PubMed, MAbs) - "In non-human primates, BA3021 was well tolerated at doses of up to 10 mg/kg and showed excellent stability in vivo. These preclinical results indicate that CAB anti-ROR2 ADC is efficacious and well tolerated and may be a promising treatment for cancer patients with ROR2-expressing tumors."

Journal • Preclinical • Colorectal Cancer • Gastrointestinal Cancer • Gastrointestinal Disorder • Gastrointestinal Stromal Tumor • Genito-urinary Cancer • Hepatology • Lung Cancer • Melanoma • Non Small Cell Lung Cancer • Oncology • Osteosarcoma • Pancreatic Cancer • Pancreatic Ductal Adenocarcinoma • Renal Cell Carcinoma • Sarcoma • Solid Tumor • ROR2

Phase 2 Trial of ozuriftamab vedotin (Oz-V), CAB-ROR2-ADC (NCT05271604) in treatment-refractory SCCHN (median of 3 prior lines of treatment) (GlobeNewswire) - P2 | N=290 | NCT05271604 | Sponsor: BioAtla, Inc. | "Oz-V monotherapy continues to deliver responses among patients with 2L+ SCCHN at the 1.8 mg/kg Q2W dosing regimen; ORR, DOR, PFS, and OS data capture ongoing. Updated data presented at the Mayo Multidisciplinary Head and Neck Cancer Symposium on March 27, 2025....Differentiated anti-tumor activity observed particularly in treatment-refractory and metastatic HPV-positive SCCHN, which is poorly served by EGFR inhibitors (n=11). 45% ORR (confirmed and unconfirmed); 27% confirmed so far with a DOR >5.3 months with multiple patients remaining on treatment. 100% disease control. The one patient who achieved a CR continues in complete remission, now at greater than 16 months ongoing. Oz-V continues to be well-tolerated, consistent with previous reports."

P2 data • Squamous Cell Carcinoma of Head and Neck

BioAtla Announces Two Poster Presentations at Upcoming Medical Meetings (GlobeNewswire) - "BioAtla...announced two abstracts accepted for poster presentations at the upcoming European Lung Cancer Congress (ELCC) 2025 Scientific Committee and Mayo Clinic Multidisciplinary Head and Neck Cancer Symposium 2025, to be held in Paris, France from March 26–29, 2025 and in Scottsdale, AZ from March 27–29, 2025, respectively....Venue: ELCC 2025; Title: Exploratory Analysis of Overall Survival among Non-Small Cell Lung Cancer (NSCLC) Patients with Mutated KRAS in a Phase 2 Trial of Mecbotamab Vedotin (CAB-AXL-ADC)....Venue: Mayo Clinic Multidisciplinary Head and Neck Cancer Symposium 2025; Title: Ozuriftamab Vedotin (BA3021), a Conditionally Binding ROR2-ADC; Phase 2 experience in Patients with Heavily Pretreated Squamous Cell Carcinoma of the Head and Neck."

P2 data • Non Small Cell Lung Cancer • Squamous Cell Carcinoma of Head and Neck

CRI-CCTG-0003/IND.240: Immunotherapy Platform Study in Platinum Resistant High Grade Serous Ovarian Cancer (clinicaltrials.gov) - P2 | N=60 | Recruiting | Sponsor: Canadian Cancer Trials Group | Trial completion date: Jun 2025 ➔ Dec 2025 | Trial primary completion date: Dec 2024 ➔ Jun 2025

Trial completion date • Trial primary completion date • High Grade Serous Ovarian Cancer • Oncology • Ovarian Cancer • Solid Tumor

BA3021-001: CAB-ROR2-ADC Safety and Efficacy Study in Patients With TNBC or Head & Neck Cancer (Ph1) and NSCLC or Melanoma (Ph2) (clinicaltrials.gov) - P1/2 | N=132 | Completed | Sponsor: BioAtla, Inc. | Active, not recruiting ➔ Completed | N=420 ➔ 132

Enrollment change • Trial completion • Breast Cancer • Head and Neck Cancer • Lung Cancer • Melanoma • Non Small Cell Lung Cancer • Oncology • Solid Tumor • Triple Negative Breast Cancer

BA3021-001: CAB-ROR2-ADC Safety and Efficacy Study in Patients with TNBC or Head & Neck Cancer (Ph1) and NSCLC or Melanoma (Ph2) (clinicaltrials.gov) - P1/2 | N=420 | Active, not recruiting | Sponsor: BioAtla, Inc. | Recruiting ➔ Active, not recruiting | Trial completion date: Dec 2025 ➔ Dec 2024 | Trial primary completion date: Dec 2025 ➔ Dec 2024

Combination therapy • Enrollment closed • Metastases • Trial completion date • Trial primary completion date • Breast Cancer • Head and Neck Cancer • Lung Cancer • Melanoma • Non Small Cell Lung Cancer • Oncology • Solid Tumor • Triple Negative Breast Cancer