Our lead programs include APR-1051, a next-generation inhibitor of the WEE1 kinase, and ATRN-119, a novel macrocyclic ATR inhibitor. These two investigational therapies are the cornerstones of our precision medicine pipeline.
Both compounds were discovered internally at Aprea and are being developed by our experienced team of chemists, scientists, and clinicians. Together, they represent our commitment to advancing innovative treatments for cancer patients with unmet medical needs, while delivering meaningful impact to patients and generate long-term value for shareholders.
Our therapeutic assets—and the proprietary technologies we use to validate them—reflect our commitment to giving cancer patients more choices.
| MOLECULE | SCHEDULE | ALTERATIONS | INDICATION | PRECLINICAL | IND | PHASE 1 | ANTICIPATED MILESTONES |
|---|---|---|---|---|---|---|---|
| WEE1 Inhibitor APR-1051 | Oral QD | CCNE1, CCNE2, FBXW7, PPP2R1A | Advanced Solid Tumors | Monotherapy
|
Potential Safety/Efficacy Clinical Data Complete Dose Escalation 2Q 2027 |
||
| HPV+ | Oropharyngeal Squamous Cell Carcinoma Cervical, Vaginal, or Vulvar Squamous Cell Carcinoma | ||||||
| KRASG12/13 & TP53 | CRC | ||||||
| Regardless of Biomarker Status | Uterine Serous Carcinoma |
||||||
| ATR Inhibitor ATRN-119, (Mosipasertib) |
Oral QD | ATRi Synthetic Lethal Gene Alterations |
Advanced Solid Tumors (Ovarian, CRC, Lung) Hematological Cancers (AML, MDS) |
Monotherapy, RP2D Determined
|
Potential Collaborations On Combining ATRN-119 with ADCs, Chemo, Radiation or I/O |
||
| DYRK1 Inhibitor APR-1602 | Oral | TBD | Solid Tumors & Hematological Cancers |
Monotherapy
|
Ready to Enter IND |
||
WEE1 is a protein kinase that helps regulate the cell cycle by preventing abnormal progression. Specifically, WEE1 prevents the premature entry of cells into both the DNA synthetic (S phase) and cell division (mitosis) phases of the cell cycle, ensuring that cells only divide after properly duplicating and repairing their DNA. By preforming these functions, WEE1 plays a crucial role in maintaining genome stability and cell survival, epically during periods of rapid cell division, a hallmark of cancer. As a result, cancer cells are particularly reliant on WEE1 for growth and survival.
APR-1051 is an orally bioavailable, highly potent, and selective small molecule inhibitor of WEE1. APR-1051 has demonstrated strong anti-proliferative activity across multiple cancer cell lines and in mouse models. APR-1051 also exhibits favorable pharmacodynamic properties, including lower off-target inhibition of three members of the PLK family of kinases (PLK1, PLK2, and PLK3).
Preliminary results from the ongoing Phase 1 study provide early clinical proof-of-concept of APR-1051. In addition, APR-1051 has been well tolerated to date.
These results strengthen Aprea’s conviction that APR-1051 has the potential to deliver a favorable therapeutic window, supporting its potential to be a differentiated WEE1 kinase inhibitor for patients with genomically defined solid tumors who have limited treatment options.
The ataxia telangiectasia and Rad3-related (ATR) kinase is a key regulator of the DNA damage response, playing a central role in maintaining genomic instability and controlling cell proliferation. By coordinating cellular responses to replication stress and damage, ATR allows cancer cells to survive despite rapid proliferation and defective DNA repair mechanisms. Inhibiting ATR disrupts these survival pathways, potentially making cancer cells more vulnerable to treatment. To leverage this vulnerability, Aprea Therapeutics has developed a highly potent and selective ATR inhibitor, ATRN-119, the first macrocyclic ATR inhibitor to enter clinical trials, representing a novel class of targeted therapy.
During 4Q 2025 Aprea determined the recommended Phase 2 dose (RP2D) to be 1,100 mg for the once daily dosing for ATRN-119. Following RP2D determination, Aprea is currently in discussions with leading academic institutions to evaluate ATRN-119 in combination with radiation in HPV-positive head and neck cancer. Additional investigator-led studies evaluating ATRN-119 with immuno-oncology therapies and antibody-drug conjugates are also being explored.
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