-- Topline global pivotal Phase 3 data for firmonertinib in first-line EGFR 
      exon 20 insertion mutant NSCLC expected 2H 2026 
 
   -- ARR-217, a CDH17 targeted ADC for gastrointestinal malignancies, advanced 
      to Phase 1b dose optimization 
 
   -- Dosing of first patient with ARR-002, a dual-targeting MUC16/NaPi2b 
      tetravalent ADC with initial focus in ovarian and endometrial cancers 
      expected Q3 2026 
 
   -- Cash and investments of $373.1 million as of June 30, 2026 expected to 
      fund operations into 2028 

NEWTOWN SQUARE, Pa., Aug. 12, 2026 (GLOBE NEWSWIRE) -- ArriVent BioPharma, Inc. (Company or ArriVent) (Nasdaq: AVBP), a clinical-stage company dedicated to accelerating the global development of innovative biopharmaceutical therapeutics, today reported financial results for the second quarter ended June 30, 2026, and highlighted recent Company progress.

"Our FURVENT and ALPACCA global pivotal trials have the potential to establish firmonertinib as a first-line treatment option for uncommon EGFR mutations in non-small cell lung cancer (NSCLC), addressing a significant unmet need for patients who remain underserved by current therapies," said Bing Yao, CEO of ArriVent. "In parallel, we continue to build a differentiated ADC portfolio, with ARR-217 advancing into dose optimization and ARR-002 advancing in clinical development. We look forward to presenting pivotal topline data from our global FURVENT study for firmonertinib and initial Phase 1 data for ARR-217."

Second Quarter 2026 and Recent Highlights

Firmonertinib

   -- Phase 3 study supported by crystal structure data presented at AACR. 
      Ongoing pivotal Phase 3 study in frontline EGFR exon 20 insertion mutant 
      NSCLC supported by preclinical data for EGFR inhibitor firmonertinib 
      showcased high resolution crystal structure data at the 2026 American 
      Association for Cancer Research (AACR) Annual Meeting. 

Pipeline

   -- Initiated Phase 1b Dose Optimization of ADC lead ARR-217 (MRG007). 
      ArriVent has initiated Phase 1b dose optimization for ARR-217, a CDH17 
      targeted ADC, in patients with gastrointestinal malignancies in 
      partnership with Lepu Biopharma Co., Ltd. 
 
   -- Clinically advancing ARR-002 in ovarian and endometrial cancer. ArriVent 
      advancing ARR-002, a novel dual-target MUC16/NaPi2b tetravalent ADC, into 
      the clinic through a first-in-human study evaluating safety, dosing, and 
      early signals of efficacy in patients with ovarian and endometrial 
      cancers following Investigational New Drug $(IND)$ clearance from the Food 
      and Drug Administration (FDA) in May 2026. 
 
   -- Greater China license agreement with Allist for ARR-002. ArriVent entered 
      into an exclusive licensing agreement with Shanghai Allist 
      Pharmaceuticals Co., Ltd. (Allist) to develop and commercialize ARR-002 
      in Greater China, which includes mainland China, Hong Kong, Macau and 
      Taiwan, with all other rights retained by ArriVent. 

Upcoming Milestones

   -- Firmonertinib pivotal EGFR exon 20 insertion data. Top-line data from the 
      global pivotal FURVENT Phase 3 (NCT05607550) study for first-line EGFR 
      exon 20 insertion mutant NSCLC is anticipated in 2H 2026. 
 
   -- Initial Phase 1 data for ARR-217. Initial Phase 1 dose escalation data 
      for ARR-217 planned to be presented at a future medical conference. 
 
   -- Dosing of first patient with ARR-002. Dosing of first patient with 
      ARR-002 in a Phase 1 trial expected in the third quarter of 2026. 

2026 Financial Results

   -- As of June 30, 2026, the Company had cash and investments of $373.1 
      million, which is expected to fund operations into 2028. 
 
   -- Net cash used in operations was $81.5 million and $94.1 million for the 
      six months ended June 30, 2026 and 2025, respectively. 
 
   -- Research and development expenses were $80.0 million and $89.0 million 
      for the six months ended June 30, 2026 and 2025, respectively. 
 
   -- General and administrative expenses were $18.8 million and $11.4 million 
      for the six months ended June 30, 2026 and 2025, respectively. 
 
   -- Net loss was $93.2 million and $95.8 million for the six months ended 
      June 30, 2026 and 2025, respectively. 

About ArriVent

ArriVent is a clinical-stage biopharmaceutical company dedicated to the identification, development, and commercialization of differentiated medicines to address the unmet medical needs of patients with cancers. ArriVent seeks to utilize its team's deep drug development experience to maximize the potential of its lead development candidate, firmonertinib, and advance a pipeline of novel therapeutics, such as next-generation antibody drug conjugates, through approval and commercialization.

About Firmonertinib

Firmonertinib is an oral, highly brain-penetrant, and broadly active mutation-selective epidermal growth factor receptor (EGFR) inhibitor active against both classical and uncommon EGFR mutations, including PACC and exon 20 insertion mutations. In March 2021, firmonertinib was approved in China for first-line advanced non-small-cell lung cancer (NSCLC) with EGFR exon 19 deletion or L858R mutations and for patients with previously treated locally advanced or metastatic NSCLC with EGFR T790M mutation, otherwise known as EGFR classical mutations.

Firmonertinib was granted U.S. Food and Drug Administration (FDA) Breakthrough Therapy Designation for the treatment of patients with previously untreated locally advanced or metastatic non-squamous NSCLC with EGFR exon 20 insertion mutations. Firmonertinib was also granted U.S. FDA Orphan Drug Designation for the treatment of NSCLC with EGFR mutations or human epidermal growth factor receptor 2 (HER2) mutations or HER4 mutations.

Firmonertinib is currently being studied in a global Phase 3 trial for first-line NSCLC patients with EGFR exon 20 insertion mutations (FURVENT; NCT05607550) and in a global Phase 3 study in first line NSCLC patients with EGFR PACC mutations (ALPACCA; NCT07185997).

About EGFR mutant NSCLC

Globally, lung cancer is the leading cause of cancer-related deaths among men and women. NSCLC is the predominant subtype of lung cancer, accounting for approximately 85% of all cases. Mutational activation of the EGFR is a frequent and early event in the development of NSCLC. EGFR mutations are divided into classical and uncommon. EGFR exon 20 insertion mutations are a group of uncommon EGFR mutations and constitute approximately 9% of all EGFR mutations. PACC mutations are another group of uncommon EGFR mutations and represent approximately 12% of all EGFR mutations. Patients with NSCLC whose tumors harbor uncommon EGFR mutations have significantly lower life expectancy with available therapies and represent an area of unmet medical need.

About EGFR PACC mutations

P-loop and <ALPHA>C-helix compressing (PACC) EGFR mutations are a distinct set of approximately 70 mostly missense activating mutations within the kinase domain of EGFR. They are similar to exon 20 insertion mutations in narrowing the drug binding pocket to affect tyrosine kinase inhibitor activity. PACC mutations are diagnosed through commercially available NGS and most PCR tests. Patients with PACC mutations have limited treatment options, and there is no broadly utilized standard of care treatment for first-line PACC mutant patients.

About FURVENT

FURVENT is a global, pivotal 3 arm Phase 3 clinical trial of firmonertinib in first-line non-squamous locally advanced or metastatic NSCLC patients with exon 20 insertion mutations being conducted jointly with our partner Allist (NCT05607550). The FURVENT clinical trial is designed to assess the safety and efficacy of firmonertinib administered at either 160 mg or 240 mg, once-daily with each dose being compared to platinum-based chemotherapy with pemetrexed, the current first-line standard of care. The primary endpoint of this study is PFS by BICR per Response Evaluation Criteria in Solid Tumors (RECIST) 1.1. Secondary endpoints in patients with brain metastases at baseline include brain-specific CNS overall response rate (CNS-ORR) and CNS-PFS by modified RECIST (mRECIST). The study enrolled 398 patients globally, including from sites in the United States, Europe and certain Asian countries including Japan and China.

About ALPACCA

ALPACCA is a global, pivotal 2 arm Phase 3 clinical trial of firmonertinib in first-line non-squamous locally advanced or metastatic NSCLC patients with PACC mutations being conducted jointly with our partner Allist (NCT07185997). The ALPACCA trial is evaluating firmonertinib 240 mg once daily versus investigator's choice of osimertinib or afatinib in first-line patients with EGFR PACC mutant NSCLC. The 240 mg dose of firmonertinib was selected for pivotal development based on compelling data showing a 16-month median PFS and a confirmed 68% ORR by BICR in the FURTHER trial (NCT05364073). The primary endpoints of this study are ORR and PFS by BICR per RECIST.

About ARR-217

ARR-217 (also known as MRG007) is a cadherin-17 (CDH17) targeted ADC, with a glycan-linked, exatecan-based antibody drug conjugate. CDH17 is a membranous cell adhesion molecule and is frequently overexpressed in colorectal cancer $(CRC)$ and several other gastrointestinal (GI) cancers, with limited expression in normal intestinal tissue and pancreatic duct. The differential expression profile in tumor versus normal tissue makes it an attractive target for antibody-drug conjugate $(ADC)$ in GI cancers, particularly CRC. ARR-217 is currently being evaluated in a multi-center, phase I study to evaluate the safety, tolerability, efficacy, and pharmacokinetics in patients with unresectable locally advanced or metastatic solid tumors (NCT07066657).

About ARR-002