Curated News
By: NewsRamp Editorial Staff
November 04, 2025
Cancer Breakthrough: Zelenirstat Shows 1000x Potency as ADC Payload
TLDR
- Pacylex and Heidelberg Pharma's collaboration demonstrates zelenirstat's potential as a novel ADC payload, offering a competitive edge in cancer treatment with significantly enhanced potency.
- Zelenirstat functions as an NMT inhibitor payload in ADCs, showing 20 to 1000-fold increased potency against cancer cell lines through targeted delivery mechanisms.
- This innovative cancer therapy partnership advances targeted treatment options, potentially improving survival outcomes and quality of life for patients with difficult-to-treat cancers.
- Pacylex transforms their oral cancer drug into powerful ADC payloads, achieving remarkable potency increases by combining novel mechanisms with cutting-edge antibody technology.
Impact - Why it Matters
This collaboration represents a significant advancement in cancer treatment that could transform how we approach both hematologic and solid tumor cancers. The development of new ADC payloads is crucial because current cancer treatments often face limitations in effectiveness and side effects. Zelenirstat's novel mechanism of action targeting multiple cancer cell growth processes, combined with its demonstrated safety profile, offers hope for more effective and targeted cancer therapies. For patients facing refractory cancers with limited treatment options, this research could lead to new therapeutic alternatives that are both more potent and better tolerated. The 20 to 1000-fold increase in potency when used as an ADC payload suggests this approach could significantly improve treatment outcomes while potentially reducing side effects compared to conventional chemotherapy. As cancer remains a leading cause of death worldwide, innovations like this partnership between Pacylex and Heidelberg Pharma represent important steps forward in the ongoing battle against this devastating disease.
Summary
Pacylex Pharmaceuticals Inc., a clinical-stage pharmaceutical company based in Edmonton, Alberta, and Heidelberg Pharma AG, a German biotech firm, have announced a groundbreaking collaboration to test zelenirstat and PCLX-002 in antibody drug conjugates (ADCs). The companies are jointly presenting positive data at the 16th Annual World ADC conference in San Diego, showcasing results from multiple breast and prostate cancer cell lines using different ADC targeting molecules and linkers. This partnership represents a significant advancement in cancer treatment research, combining Pacylex's expertise in N-myristoyltransferase inhibitors with Heidelberg Pharma's innovative ADC technologies.
The research demonstrates that zelenirstat, a first-in-class oral NMT inhibitor currently in clinical development for hematologic cancers, shows remarkable potency when used as an ADC payload. In the studies presented, zelenirstat ADCs exhibited 20-fold to more than 1,000-fold higher potency against cancer cell lines compared to zelenirstat alone. Dr. Michael Weickert, CEO of Pacylex, emphasized that this approach not only maintains zelenirstat's activity as an oral hematologic cancer drug but significantly enhances its effectiveness against solid tumor cells when deployed as an ADC payload. The companies are aggressively exploring zelenirstat and other Pacylex molecules as targeted ADC payloads, given the compound's novel mechanism of action and established clinical safety profile from completed Phase 1 studies.
This collaboration addresses the critical need for new ADC payloads in cancer treatment, as only a limited number have entered clinical practice. Zelenirstat has demonstrated an acceptable safety profile in previous clinical trials, including a Phase 1 multiple ascending dose study published in a scientific journal, and is currently being investigated in relapsed/refractory AML patients. The FDA has granted zelenirstat both Orphan Drug Designation and Fast Track Designation for AML, with support from the US Department of Defense for initial clinical investigations. Heidelberg Pharma brings its unique ATAC technology to the partnership, being the first company to use Amanitin from the green death cap mushroom in cancer therapy, representing a new therapeutic modality in oncology treatment.
Source Statement
This curated news summary relied on content disributed by Reportable. Read the original source here, Cancer Breakthrough: Zelenirstat Shows 1000x Potency as ADC Payload
