AveragePenny
6月前
$APRE Aprea Therapeutics CEO Issues Letter to Shareholders Highlighting Pipeline Progress in 2025 and Outlook for 2026
https://www.globenewswire.com/news-release/2025/12/18/3207703/0/en/Aprea-Therapeutics-CEO-Issues-Letter-to-Shareholders-Highlighting-Pipeline-Progress-in-2025-and-Outlook-for-2026.html
DOYLESTOWN, Pa., Dec. 18, 2025 (GLOBE NEWSWIRE) -- Aprea Therapeutics, Inc. (Nasdaq: APRE) (“Aprea”, or the “Company”), a clinical-stage biopharmaceutical company developing innovative treatments that target weaknesses in cancer cells while minimizing damage to healthy cells, today issued the following letter to shareholders from Chief Executive Officer, Oren Gilad. The letter highlights the Company’s ongoing clinical progress, operational execution, and plans for 2026.
Dear Shareholders --
As 2025 comes to a close, I am proud of what Aprea has accomplished over the past 12 months and excited for the year ahead. This year, we achieved meaningful milestones that we believe validate our approach and position us for long-term growth. These accomplishments reflect our team’s hard work and dedication, and we are pleased to share them with you.
WEE1 Inhibitor Program, APR-1051
Our lead program, APR-1051, a next-generation WEE1 inhibitor, continues to demonstrate promising anti-tumor activity in our ongoing ACESOT-1051 dose-escalation study. We are enrolling patients in the 220 mg cohort (Cohort 8), and so far, through the 150mg dose, the treatment has been well tolerated with no dose-limiting toxicities (DLTs) or unexpected safety findings or issues.
We have observed disease stabilization in several patients, with the longest duration of treatment reaching 222 days. The most notable response to date is a 15% reduction in tumor burden. Encouragingly, the number of patients achieving disease stabilization appears to increase with higher doses.1
After observing encouraging early single-agent activity in a patient with HPV-positive head and neck cancer at the 70 mg dose, we amended our clinical protocol to augment the number of HPV-positive patients. We believe this approach will broaden our clinical experience in HPV-positive tumor types, an area with substantial unmet medical need, and aligns with data from our translational research collaboration with MD Anderson Cancer Center. Their preclinical studies showed strong single-agent activity across a broad panel of human and animal head and neck squamous cell carcinoma models, as well as synergy between our APR-1051 and anti-PD-1 therapy.
Near term catalysts for the ongoing APR-1051 clinical program include the availability of further safety and efficacy data in Q1 2026 and completion of dose escalation in 2026.
ATR Inhibitor Program, ATRN-119
Earlier this year, we announced that the ATRN-119 program had reached its recommended Phase 2 dose (RP2D) for once-daily dosing, and we are now shifting our focus toward evaluating combination therapies with this agent. As part of this strategic direction and to preserve cash in a still difficult fundraising environment, Aprea is pausing further enrollment in both once-daily and twice-daily monotherapy dosing arms of the ABOYA-119 study.
Building on the completion of dose escalation and supported by new preclinical data suggesting synergistic anti-tumor activity, we may consider combination strategies to expand ATRN-119’s therapeutic potential as our balance sheet strengthens. With its favorable safety profile, ATRN-119 is well positioned for use alongside DNA-damaging agents, including radiation therapy, antibody-drug conjugates, and immune checkpoint inhibitors.
As previously disclosed, we are in discussions with leading academic centers to investigate ATRN-119 in combination with radiation and immunotherapy, based on preclinical findings that ATR inhibition may enhance anti-tumor immune responses.
We will continue to share updates on this program throughout the coming year.
Cash Runway Into Q1 2027
We remain committed to maintaining financial discipline and delivering value for our shareholders. We believe our recently completed $3.1 million (gross) private placement financing extends our cash runway into 2027 based on current projections. Our focus is on executing our programs with discipline and continuing to expand our investor relations and visibility efforts so the market better understands the value Aprea is creating.
Our strategy is to advance the science, deliver on clinical and regulatory milestones, broaden awareness of the story, and let the fundamentals drive a valuation that better reflects the opportunity.
In this last round of financing, myself, as well as our CFO, and a Board member participated alongside external investors, which included healthcare focused funds and a long-term existing shareholder, reflecting confidence in our strategy and potential.
Aprea remains committed to advancing the fight against cancer. I want to sincerely thank our dedicated employees, our engaged Board of Directors, our patients and their families, clinical investigators and our valued shareholders. Your commitment and belief in our mission are essential to everything we do.
All my best,
Oren Gilad
President & Chief Executive Officer
Aprea Therapeutics
AveragePenny
7月前
$APRE Aprea Therapeutics Reports Third quarter 2025 Financial Results and Provides a Clinical Update
https://www.globenewswire.com/news-release/2025/11/12/3186275/0/en/Aprea-Therapeutics-Reports-Third-quarter-2025-Financial-Results-and-Provides-a-Clinical-Update.html
APR-1051 (WEE1 kinase inhibitor): In ongoing Phase 1 ACESOT-1051dose-escalation trial, 3 out of 4 patients at Dose Level 6 (100 mg once daily) achieved stable disease, per RECIST v1.1, in heavily pretreated gastrointestinal and gynecologic malignancies
ATRN-119 (ATR kinase Inhibitor): RP2D of 1,100 mg once daily identified in ABOYA-119 dose-escalation study
Posters on APR-1051 and ATRN-119 featured at AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics
DOYLESTOWN, Pa., Nov. 12, 2025 (GLOBE NEWSWIRE) -- Aprea Therapeutics, Inc. (Nasdaq: APRE) (“Aprea”, or the “Company”), a clinical-stage biopharmaceutical company developing innovative treatments that exploit specific cancer cell vulnerabilities while minimizing damage to healthy cells, today reported financial results for the third quarter ended September 30, 2025, and provided a business update. The Company reported continued clinical progress across both its WEE1 and ATR inhibitor programs and has cash runway into the fourth quarter of 2026.
“We are pleased with the continued progress in our development programs, as the emerging data on both of our clinical assets demonstrate evidence of activity,” said Oren Gilad, Ph.D., President and Chief Executive Officer of Aprea. “For APR-1051, our WEE1 kinase inhibitor, we’re encouraged by early signs of anti-tumor activity to date in the ongoing ACESOT-1051 trial, including 3 out of 4 patients with stable disease in the 100 mg once daily cohort. We have recently advanced into the 150 mg once daily cohort as dose escalation in this trial continues. For ATR-119, identifying the recommended Phase 2 dose for the once daily (QD) dosing provides a solid foundation for next-stage development, and we are now considering potential combination strategies, with radiation or checkpoint inhibitors, that could expand its clinical impact. These developments reinforce Aprea’s differentiated DDR approach and our commitment to helping patients with value creating clinical catalysts anticipated in 2026.”
Key Business Updates and Potential Upcoming Key Milestones
ACESOT-1051: A Biomarker Focused, Phase 1 Trial of Oral WEE1 inhibitor, APR-1051
APR-1051 is a potent and selective small molecule WEE1 inhibitor designed to potentially solve tolerability challenges of the WEE1 class and has the potential to achieve improved clinical activity than other programs currently in development. APR-1051 is being advanced as a monotherapy in biomarker-defined cancers likely to respond to WEE1 inhibition. Among these, cancers over-expressing Cyclin E represent a high unmet medical need. Patients with Cyclin E over-expression have poor prognosis and, currently, lack effective therapies options.
APR-1051 is currently evaluated in the ongoing Phase 1 ACESOT-1051 (A Multi-Center Evaluation of WEE1 Inhibitor in Patients with Advanced Solid Tumors, APR-1051). Results from Dose Level 6 (100 mg once daily), show that 3 out of 4 patients achieved stable disease, per RECIST v1.1 in heavily pretreated gastrointestinal and gynecologic malignancies. Disease stabilization was observed in patients with FBXW7, CCNE1, and KRASG12V + TP53 alterations, molecular profiles known to drive replication stress and WEE1 dependency.
Following successful clearance of the 100 mg cohort, dose escalation has progressed to Dose Level 7 (150 mg once daily) with the goal of identifying doses that maximize therapeutic benefit while maintaining an acceptable safety profile. APR-1051 was manageable with mostly Grade 1 or 2 adverse events, which were mainly gastrointestinal events and fatigue.
A poster titled Early safety and efficacy of APR-1051, a novel WEE1 inhibitor, in patients with cancer-associated gene alterations: Updated data from ACESOT-1051 Phase 1 trial was presented on October 24, 2025at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics. This poster summarizes preliminary results from the trial with a cutoff date of September 17, 2025. A copy is available on the Aprea corporate website here.
Pending additional data, future studies of ACESOT-1051 may evaluate APR-1051 in combination with checkpoint inhibitors to address unmet medical needs across distinct patient populations.
For more information, refer to ClinicalTrials.gov NCT06260514.
ABOYA-119: Ongoing Clinical Trial Evaluating ATR inhibitor, ATRN-119
ATRN-119 is a potent and highly selective first-in-class macrocyclic ATR inhibitor, designed and developed to be used in patients with tumors harboring mutations in DDR-related genes. Cancers with mutations in DDR-related genes represent a high unmet medical need. These patients often have a poor prognosis and currently lack effective therapeutics options.
ATRN-119 is being evaluated in the open-label Phase 1/2a clinical trial (ABOYA-119) as monotherapy in patients with advanced solid tumors having at least one mutation in a defined panel of DDR-related genes. As of September 8, 2025, 43 patients with advanced solid tumors have been enrolled.
Based on results to date, Aprea has 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 strategically pausing further enrollment in both once daily and twice daily monotherapy dosing arms of the ABOYA-119 trial to consider combination studies aimed at maximizing therapeutic benefits. Aprea is currently in discussions with leading academic centers to explore combining ATRN-119 with radiation in patients with HPV+ head and neck cancer, an indication where synergistic anti-tumor effects have been observed in preclinical data. Additional investigator-led studies evaluating ATRN-119 in combination with I/O agents and antibody-drug conjugates are also being explored.
A poster titled Updated data from ABOYA-119: A phase 1/2a trial of ATRN-119, a novel macrocyclic ATR inhibitor, in patients with advanced solid tumors harboring DNA damage trial was presented on October 24, 2025 at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics. This poster summarizes preliminary results from the trial with a cutoff date of September 8, 2025. A copy can be found here.
For more information on ABOYA-119, please refer to clinicaltrials.gov NCT04905914.
Select Financial Results for the Third quarter Ended September 30, 2025
As of September 30, 2025, the Company reported cash and cash equivalents of $13.7 million compared to $22.8 million as of December 31, 2024. The Company believes its cash and cash equivalents as of September 30, 2025, will be sufficient to meet its currently projected operating expenses and capital expenditure requirements into the fourth quarter of 2026.
For the third quarter ended September 30, 2025, the Company reported an operating loss of $3.1 million, compared to an operating loss of $4.1 million in the third quarter of 2024.
Research and Development (R&D) expenses were $1.6 million for the quarter ended September 30, 2025, compared to $2.8 million for the third quarter of 2024. The decrease in R&D expenses was primarily related to higher expenses in 2024 related to study start up activities in preparation for enrollment of the first patient into ACESOT-105, our Phase 1 dose-escalation study of APR-1051, and lower expenses in 2025 related to the ABOYA-119 clinical trial to evaluate ATRN-119, our clinical-stage oral small molecule inhibitor of ATR.
General and Administrative (G&A) expenses were $1.5 million for the quarter ended September 30, 2025, compared to $1.6 million for the third quarter of 2024. The decrease in G&A expenses was primarily related to a decrease in insurance costs.
The Company reported a net loss of $3.0 million ($0.47 per basic share) on approximately 6.4 million weighted average common shares outstanding for the quarter ended September 30, 2025, compared to a net loss of $3.8 million ($0.64 per basic share) on approximately 5.9 million weighted average common shares outstanding for the comparable period in 2024
AveragePenny
7月前
$APRE Aprea Therapeutics Provides Clinical Update from ACESOT-1051 Trial Showing Early Signals of Activity for WEE1 Kinase Inhibitor APR-1051
https://www.globenewswire.com/news-release/2025/10/24/3172792/0/en/Aprea-Therapeutics-Provides-Clinical-Update-from-ACESOT-1051-Trial-Showing-Early-Signals-of-Activity-for-WEE1-Kinase-Inhibitor-APR-1051.html
3 out of 4 patients achieved stable disease (per RECIST v1.1) at the 100 mg APR-1051 dose level in heavily pretreated gastrointestinal and gynecologic malignancies
Disease stabilization observed in patients with tumors harboring mutations relevant to WEE1 kinase inhibition (FBXW7, CCNE1, KRAS G12V and TP53)
Dose escalation continues, with patients now enrolling in 150 mg cohort
Preliminary results from ACESOT-1051 trial through September 17, 2025 to be featured in poster presentation today at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics
DOYLESTOWN, Pa., Oct. 24, 2025 (GLOBE NEWSWIRE) -- Aprea Therapeutics, Inc. (Nasdaq: APRE) (“Aprea”, or the “Company”), a clinical-stage biopharmaceutical company developing innovative treatments that exploit specific cancer cell vulnerabilities while minimizing damage to healthy cells, today provided an update on the ongoing Phase 1 ACESOT-1051 (A Multi-Center Evaluation of WEE1 Inhibitor in Patients with Advanced Solid Tumors, APR-1051) study. The latest results show that, at the 100 mg APR-1051 dose level, 3 out of 4 patients achieved stable disease, as measured using RECIST v1.1 criteria.
A poster titled Early safety and efficacy of APR-1051, a novel WEE1 inhibitor, in patients with cancer-associated gene alterations: Updated data from ACESOT-1051 Phase 1 trial will be presented today at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics. The poster, to be presented by Drs. Timothy Yap MBBS, PhD, FRCP, University of Texas MD Anderson Cancer Center and lead investigator of the study, and Philippe Pultar, MD, Senior Medical Advisor at Aprea, summarizes preliminary results from the trial with a cutoff date of September 17, 2025. A copy of the poster will be available on Investors page of the Aprea corporate website under “Investor Presentations & Resources.”
“We continue to be encouraged by these early clinical findings, which demonstrate signals of anti-tumor activity with APR-1051 in a heavily pre-treated patient population,” said Dr. Pultar. “We believe the observation of disease control in tumors harboring FBXW7, CCNE1, and KRAS mutations align with our mechanistic understanding of WEE1 inhibition and reinforces the scientific rationale for APR-1051 development. We believe these promising data provide an important foundation as we continue with dose escalation in the ongoing study and we look forward to providing further updates as we advance to higher dose level in the ongoing study.”
ACESOT-1051 Clinical Update (data cutoff October 19, 2025)
The primary objective of the trial is to characterize the safety profile, dose-limiting toxicity, maximum tolerated dose or maximum administered dose, and recommended Phase 2 dose of APR-1051. Secondary objectives are to 1) to characterize the pharmacokinetics of APR-1051 and the major metabolites and active metabolites of APR-1051, and 2) to assess preliminary efficacy of APR-1051
Results from Dose Level 6 (100 mg), show 3 out of 4 patients achieved stable disease, per RECIST v1.1 in heavily pretreated gastrointestinal and gynecologic malignancies
Disease stabilization was observed in patients with FBXW7, CCNE1, and KRASG12V + TP53 alterations
Favorable tolerability: No dose limiting toxicities (DLTs) or unexpected safety issues reported to date.
Following successful clearance of the 100 mg cohort, dose escalation has progressed to Dose Level 7 (150 mg)
For more information on ACESOT-1051, refer to ClinicalTrials.gov NCT06260514.
Individual Patient Results
86-year-old female with rectal cancer: Treated at a 100 mg dose after five prior lines, the patient achieved stable disease (-13% reduction). Tumor harbored FBXW7 mutation which is a mechanistically relevant biomarker for WEE1 inhibition. 145 days on treatment and ongoing
55-year-old male with rectal cancer: Treated at a 100 mg dose after four prior lines, the patient achieved stable disease (+1%). Tumor harbored KRASG12V + TP53-mutant patient supports mechanistic activity in this genotype. 63 days on treatment and ongoing
73-year-old female with endometrial cancer: Treated at a 100mg after five prior lines, patient achieved stable disease by RECIST v1.1 criteria (+15%) at the first evaluation before voluntarily withdrawing consent after approximately two months of treatment. Tumor harbored CCNE1 and TP53 mutations supports mechanistic activity in this genotype.
50-year-old female with colon cancer: Treated at 100mg after two prior lines. This patient had disease progression at first assessment (8 weeks).
AveragePenny
8月前
$APRE Aprea Therapeutics Establishes Recommended Phase 2 Dose (RP2D) for ATRN-119, Considering Combination Therapies
https://www.globenewswire.com/news-release/2025/10/15/3167027/0/en/Aprea-Therapeutics-Establishes-Recommended-Phase-2-Dose-RP2D-for-ATRN-119-Considering-Combination-Therapies.html
ATRN-119 (ATR Inhibitor): RP2D of 1,100 mg once daily identified in ongoing ABOYA-119 dose-escalation study
Further ATRN-119 monotherapy enrollment paused with strategic focus on high-value combination
Company is prioritizing its lead program, WEE1 kinase inhibitor APR-1051
DOYLESTOWN, Pa., Oct. 15, 2025 (GLOBE NEWSWIRE) -- Aprea Therapeutics, Inc. (Nasdaq: APRE) (“Aprea”, or the “Company”), a clinical-stage biopharmaceutical company developing innovative treatments that exploit specific cancer cell vulnerabilities while minimizing damage to healthy cells, today announced that it has determined the recommended Phase 2 dose (RP2D) of 1,100 mg once daily for ATRN-119, its oral ATR inhibitor in the monotherapy arm of the ongoing ABOYA-119 Phase 1/2a dose-escalation study, in patients with advanced solid tumors.
ATR program
Building on the completion of dose escalation and supported by new preclinical data suggesting potential synergistic anti-tumor effects, Aprea is considering further ATRN-119 development in combination approaches that could expand its therapeutic potential. The Company believes ATRN-119's mechanism of action, favorable safety profile, and pharmacologic characteristics make it an ideal candidate for combination with DNA-damaging agents, including radiation therapy, antibody-drug conjugates and immune checkpoint inhibitors.
As part of this strategic focus, Aprea is pausing further enrollment in both once daily and twice daily monotherapy dosing arms of ABOYA-119. Importantly, patients currently being dosed with ATRN-119 as part of this ongoing clinical trial will continue to have access to therapy without interruption.
The Company is currently in discussions with leading academic centers to explore combining ATRN-119 with radiation in patients with HPV+ head and neck cancer, an indication where synergistic anti-tumor effects have been observed in preclinical data. Additional investigator-led studies evaluating ATRN-119 in combination with an I/O agent and antibody-drug conjugates, are also being explored, based on preclinical evidence that ATR inhibition may enhance anti-tumor immune responses.
Phase 1 monotherapy data in the ABOYA-119 dose-escalation study, ATRN-119 demonstrated:
Favorable tolerability profile with manageable adverse events at the RP2D of 1100 mg once daily
Durable disease stabilization in heavily pretreated patients across multiple tumor types
Dose-proportional pharmacokinetics supporting once-daily dosing
Preliminary signs of clinical activity in biomarker-selected populations
“We are very pleased to have identified the recommended monotherapy Phase 2 dose for ATRN-119, which is an important step in our transition to the next stage of development,” said Oren Gilad, Ph.D., President and Chief Executive Officer of Aprea. “Based on the growing body of evidence supporting ATR inhibition as a potent sensitizer to DNA-damaging therapies and immunotherapy, we are now considering ATRN-119 in combination approaches that we believe could expand its clinical impact. We believe this candidate’s mechanism, safety profile, and pharmacologic characteristics make it a compelling candidate for pairing with other anti-cancer therapies, including radiation or checkpoint inhibitors, where synergistic anti-tumor effects have been demonstrated preclinically.”
A poster titled Updated data from ABOYA-119: A phase 1/2a trial of ATRN-119, a novel macrocyclic ATR inhibitor, in patients with advanced solid tumors harboring DNA damage will be presented at the forthcoming AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics on Friday, October 24, 2025.
WEE1 Program
Aprea continues to advance its lead program, WEE1 kinase inhibitor APR-1051 at full speed. The ongoing Phase 1, first-in-human study (NCT06260514) is actively enrolling patients at three leading clinical sites in the United States. To date, patients with advanced solid tumors harboring specific cancer-associated gene alterations have been treated with APR-1051 at doses up to 150 mg once daily. Early signals of clinical benefit, including disease stabilization in multiple patients, have been observed, supporting continued dose escalation and further clinical evaluation of APR-1051. The Company expects to report clinical data from this study later this month at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics and is planning to further explore safety, pharmacokinetics, and signals of antitumor activity.
Jimmy Quick
5年前
Overview
We are a clinical-stage biopharmaceutical company focused on developing and commercializing novel cancer therapeutics that reactivate the mutant p53 tumor suppressor protein. p53 is the protein expressed from the TP53 gene, the most commonly mutated gene in cancer. We believe that mutant p53 is an attractive therapeutic target due to the high incidence of p53 mutations across a range of cancer types and its involvement in key cellular activities such as apoptosis. Cancer patients with mutant p53 face a significantly inferior prognosis even when treated with the current standard of care, and a large unmet need for these patients remains.
Our lead product candidate, APR-246, or eprenetapopt, is a small molecule p53 reactivator that is in clinical development for hematologic malignancies, including myelodysplastic syndromes, or MDS, and acute myeloid leukemia, or AML. Eprenetapopt has received orphan drug, fast track and breakthrough therapy designations from the FDA for MDS, orphan drug and fast track designations from the FDA for AML and orphan drug designation from the European Commission for MDS and AML, and we believe eprenetapopt will be a first-in-class therapy if approved by applicable regulators.
We are conducting, supporting and planning multiple clinical trials of eprenetapopt and APR-548:
--- Phase 3 Frontline MDS Trial -- In June 2020, we completed full enrollment of 154 patients in a pivotal Phase 3 trial of eprenetapopt with azacitidine for frontline treatment of TP53 mutant MDS. The pivotal Phase 3 trial is supported by data from two Phase 1b/2 investigator-initiated trials, one in the U.S. and one in France, testing eprenetapopt with azacitidine as frontline treatment in TP53 mutant MDS and AML patients. The data from the U.S. and French Phase 1b/2 trials were published in The Journal of Clinical Oncology in January 2021 and February 2021, respectively. In December 2020, we announced that our pivotal Phase 3 trial failed to meet its predefined primary endpoint of complete remission (CR) rate. Analysis of the primary endpoint at this data cut demonstrated a higher CR rate (53% more patients achieving a CR) in the experimental arm receiving eprenetapopt with azacitidine versus the control arm receiving azacitidine alone but did not reach statistical significance. Based on a thorough analysis of the current Phase 3 trial data and comparisons to the U.S. and French Phase 1b/2 trials, we believe that despite similar types and frequency of adverse events observed in the Phase 3 experimental arm and the Phase 1b/2 trials, patients in the Phase 3 experimental arm experienced substantially more study treatment dose modifications compared to the experience in the U.S. and French Phase 1b/2 trials. We believe that the dose modifications of eprenetapopt and azacitidine led to undertreatment in the Phase 3 experimental arm that negatively impacted efficacy, particularly the primary endpoint of CR rate. We continue to follow patients who remain on-study and anticipate discussing with FDA the Phase 3 data and future possible regulatory pathways in the second half of 2021.
--- Phase 2 MDS/AML Post-Transplant Trial -- We have completed enrollment of 33 patients in a single-arm, open-label Phase 2 trial evaluating eprenetapopt with azacitidine as post-transplant maintenance therapy in TP53 mutant MDS and AML patients who have received an allogeneic stem cell transplant. The primary endpoint of the trial is the rate of relapse-free survival (RFS) at 12 months, with a published benchmark of ~30%. An interim analysis in April 2021 showed a 62% rate of RFS at 12 months, with a median RFS of 462 days. An interim analysis of overall survival (OS) showed a 77% OS at 1 year, with a median number of events not yet reached. We anticipate initial results from the primary endpoint of RFS at 12 months in the second quarter of 2021.
---- Phase 1/2 AML Trial -- We are currently enrolling a Phase 1/2 clinical trial evaluating the safety, tolerability, and preliminary efficacy of eprenetapopt therapy in TP53 mutant AML patients. The lead-in portion of the trial evaluated the tolerability of eprenetapopt with venetoclax, with or without azacitidine, and no dose-limiting toxicities were observed in 12 patients receiving either regimen. Based on these results, we have expanded the trial to treat 33 additional frontline TP53 mutant AML patients with the combination of eprenetapopt, venetoclax and azacitidine. In the 19 frontline AML patients who are evaluable for efficacy with the triplet regimen, we have observed a 63% CR + CRi composite response rate and a 31% CR rate. We anticipate completion of enrollment in the triplet regimen expansion cohort during the second quarter of 2021 and availability of preliminary response rate data from the cohort also in the second quarter of 2021.
--- Phase 1 NHL Trial -- We are currently enrolling a Phase 1 clinical trial in relapsed/refractory TP53 mutant chronic lymphoid leukemia (CLL) assessing eprenetapopt with venetoclax and rituximab and eprenetapopt with ibrutinib in order to further assess eprenetapopt in hematological malignancies. The first patient was enrolled in the first quarter of 2021. We are also planning to evaluate the combination of eprenetapopt with venetoclax in relapsed/refractory mantle cell lymphoma.
--- Phase 1/2 Solid Tumor Trial – We are currently enrolling a Phase 1/2 clinical trial in relapsed/refractory gastric, bladder and non-small cell lung cancers assessing eprenetapopt with anti-PD-1 therapy. The dose-escalation phase of the trial enrolled 6 patients with advanced solid tumors and no dose-limiting toxicities were observed. Based on these results, we are enrolling expansion cohorts for patients with advanced gastric, bladder and non-small cell lung cancers and have currently enrolled 15 patients across these expansion arms. A poster presentation for this trial has been accepted for presentation at the 2021 ASCO Annual Meeting (abstract TPS3161).
--- APR-548 Phase 1 Trial – Our second product candidate, APR-548, is a next generation p53 reactivator that is being developed in an oral dosage form. We have planned a Phase 1 dose-escalation clinical trial evaluating safety, tolerability, and preliminary efficacy of APR-548 with azacitidine in frontline and relapsed/refractory MDS patients. We anticipate the first patient to be enrolled in the second quarter of 2021.