EQS-News: Pentixapharm Announces Advancement of PentixaTher to Fourth Dose Level in Acute Myeloid Leukemia Trial

 Achieves Key Milestone with CXCR4-based Radiotherapeutic

• Favorable safety profile enables advancement of radiolabeled PentixaTher to fourth of five planned activity dose levels in investigator-initiated PENTILULA Phase 1/2 trial
• Milestone marks important step for novel radiotherapeutic candidate in high unmet need indication with limited treatment options and poor prognosis

 Berlin, Germany, September 26, 2025 – Pentixapharm AG (Frankfurt Prime Standard: PTP), an advanced clinical-stage biotech, developing novel radiopharmaceuticals, today announced that its CXCR4-targeting radiolabeled candidate PentixaTher has advanced to the fourth dose level in the investigator-initiated PENTILULA Phase 1/2 study in acute myeloid leukemia (AML).

Based on favorable safety findings at the third dose level of 7.5 GBq, the investigator-initiated trial received approval from the independent Data Safety Monitoring Board (DSMB) to advance to the fourth of five planned dose levels at 10 GBq, underscoring PentixaTher’s tolerability to date. Importantly, this advancement not only reinforces the compound’s safety profile but also moves the study into a dose range with a higher likelihood for meaningful clinical efficacy. If favorable safety signals continue, the study is expected to escalate to a fifth and final dose level of 12.5 GBq.

AML is the most common acute leukemia in adults, with approximately 20,000 new cases annually in the U.S. and 17,000 new cases annually in Europe. Five-year survival rates range between approximately 32 and 37%, respectively.

“Advancing to higher dose levels marks a key step in validating the therapeutic potential and promise of PentixaTher,” said Dirk Pleimes, MD, CEO/CMO of Pentixapharm. “The encouraging results in this investor-led effort highlight the potential of CXCR4 as a powerful target for hematologic cancers and demonstrate the promise of radiopharmaceuticals to expand treatment options where medical need is greatest. The trial is expanding the clinical evidence base for CXCR4-targeted therapy to expand the boundaries of radiopharmaceuticals.”

Professor Françoise Kraeber-Bodéré, Nuclear Medicine Department, CHU Nantes, Principal Investigator, commented: “We are encouraged by the favorable safety profile observed to date, which has enabled us to move to higher activity dose levels. At dose level four, we are now entering a range considered of potentially higher effectiveness, and we look forward to evaluating the clinical impact in this high-need patient population.”

Professor Patrice Chevallier, Hematology Department, CHU Nantes added: “For patients with advanced AML, treatment options are limited, and prognosis in this often heavily pretreated population is poor. Reaching this dose level with an acceptable safety profile provides new hope that CXCR4-targeted radiopharmaceuticals could one day become a meaningful addition to the therapeutic landscape.”

About PentixaTher and the PENTILULA Phase 1/2 Study

Radiolabeled PentixaTher is a novel radiotherapeutic designed to selectively target the chemokine receptor CXCR4, a key player in the bone marrow microenvironment that is frequently overexpressed in aggressive hematological malignancies. The compound is labeled for the PENTILULA study with 177-lutetium, a clinically well-established isotope, enabling precise delivery of a targeted radiation payload. PentixaTher is currently being evaluated in the PENTILULA Phase 1/2 study (ClinicalTrials.gov ID: NCT06356922), initiated in November 2024. The multicenter, open-label, dose-escalation trial is led by an experienced investigator team at the University Hospital of Nantes and conducted at three additional clinical sites in France. It aims primarily to assess the safety and tolerability of PentixaTher, with secondary objectives including preliminary measures of clinical activity such as overall response rate, complete response rate, and overall survival. The study is supported by the French Ministry of Health.

About Pentixapharm

Pentixapharm is an advanced clinical-stage biotech expanding the boundaries of radiopharmaceuticals. Headquartered in Berlin, Germany, the company develops first-in-class ligand- and antibody-based radiopharmaceuticals designed to transform patient care across oncology and beyond. Its late-stage pipeline is anchored by CXCR4-targeted programs, including a Phase 3-ready diagnostic candidate for primary aldosteronism and pioneering therapeutic programs in a number of hematological and solid cancers. Furthermore, Pentixapharm is advancing a next-generation antibody platform targeting CD24, an emerging immune-escape marker over-expressed in multiple hard-to-treat cancers. Complemented by reliable isotope supply from Eckert & Ziegler, and a robust global clinical network, Pentixapharm is uniquely positioned to deliver innovative radiopharmaceuticals that address high unmet need, improve patient outcomes, and create significant growth opportunities in one of the fastest-growing areas of precision medicine.

About Nantes University Hospital

Nantes University Hospital (CHU de Nantes) is one of France's leading healthcare institutions, recognized for its excellence in various medical specialties including cardiology, transplants, oncology, and neuroscience. The hospital is also a key player in medical research and innovation, conducting clinical trials and contributing to significant advancements in healthcare, in particular in nuclear medicine and hematology. [¹⁷⁷Lu]Lu-PentixaTher is produced by ARRONAX, the hospital radiopharmacy unit (APUI), which is specially authorized for the preparation of the radiopharmaceutical investigational product.

Pentixapharm Investor and Media Contact

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