FDA clears Aprea Therapeutic’s Investigational New Drug (IND) application (IND 169359) for oral WEE1 Inhibitor, APR-1051
Aprea to initiate the Phase 1 ACESOT-1051 trial. Learn more

Clinical Trials Put Discovery Into Action


Every day, Aprea is one step closer to bringing breakthrough DDR-targeted therapies to market.

The goal of clinical trials is to advance our robust pipeline of novel, highly selective therapies and quickly bring them to market to benefit the greatest number of cancer patients possible.

Current Clinical Trials

Aprea’s leading candidates, ATRN-119 and APR-1051, are a significant opportunity to address the unmet medical needs of cancer patients.

Aprea is in the beginning stages of developing next-generation cancer therapies. Our lead candidate, ATRN-119, an ATR inhibitor, is currently in a Phase 1/2a trial, and our second candidate, APR-1051, a WEE1 inhibitor, will begin clinical studies in 1H 2024. Initial findings and data indicate a strong foundation for moving forward in both programs.

Lead Candidate, ATRN-119

Aprea’s macrocyclic ATR inhibitor, ATRN-119, is undergoing its first-in-human phase 1/2a trial in patients with advanced solid tumors.

Outcomes to date show:

  • Daily dosing of ATRN-119 may result in persistent tumor-reducing effect.
  • In vivo combination studies demonstrate significant synergy between ATRN-119 and poly (ADP-ribose) polymerase (PARP) inhibition.
  • No dose-limiting toxicities have been reported in patients treated with ATRN-119 as of cohort 3 dose level. Dose escalation continues to explore higher dose levels.
  • ATRN-119 appears to be well tolerated with a manageable toxicity profile.
  • This Phase 1/2a study is currently enrolling eligible study patients at four U.S. sites.

We anticipate ATRN-119 Phase 1 readout to be available in 4Q 2024, and to initiate Phase 2a expansion stage during 1Q 2025.

Preclinical Studies of APR-1051 Monotherapy

APR-1051 shows promise as a potent and highly selective WEE1 inhibitor that may offer new ways to treat CCNE1AMP cancers.

Preclinical Studies indicate:

  • APR-1051 is highly selective WEE1 inhibitor that may limit off-target toxicity.
  • Structural differentiation from other WEE1 Inhibitors and potentially favorable PK properties make APR-1051 a standout among existing solutions.
  • APR-1051 appears to cause lower inhibition of hERG, a potential indicator of low cardiotoxicity and causes minimal anemia at dose and scheduling that suppress tumor growth.

These findings have justified IND-enabling studies for clinical development of APR-1051.

A Planned Phase I, Open-Label, Multicenter, First-In-Human Study of WEE1

Aprea will be investigating the safety, tolerability, pharmacokinetics and preliminary efficacy of APR-1051 in patients with advanced solid tumors.

We will be addressing unmet medical needs in potential specific target populations that may include:

  • Ovarian, colorectal, prostate and breast cancers
  • Platinum-resistant
  • PARP-resistant
  • Hematological
  • Gastrointestinal

Expanded Access / Compassionate Use Policy


Expanded access, also known as compassionate use, may be an option for some individuals with serious or life-threatening conditions, who have exhausted all available medical options and do not qualify for clinical trials. Given the stage of development for our investigational agents, Aprea is currently not offering expanded use programs.

Please continue to monitor clinicaltrials.gov for additional options and our website for changes to our Expanded Use programs.

Consistent with the 21st Century Cures Act, Aprea may revise this Expanded Access policy at any time. This policy applies to all of Aprea’s investigational products.