For patients with acute myeloid leukemia (AML) whose cancer has stopped responding to venetoclax, treatment options are devastatingly limited. Pacylex is developing zelenirstat, a novel therapy designed to overcome venetoclax resistance and potentially restore the effectiveness of this important cancer drug.
Your support will help Pacylex prepare for a Phase 2a clinical trial in 20 patients, including finalizing trial sites and manufacturing the clinical capsules needed to begin treatment. A contribution today can help move this promising therapy from the laboratory to patients who urgently need new options – and advance a broader technology that could one day help overcome treatment resistance across multiple cancers.
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Pacylex is developing zelenirstat, a novel cancer therapy designed to overcome treatment resistance in acute myeloid leukemia (AML) – an aggressive blood cancer where patients who stop responding to standard therapies have very few options.
Venetoclax is one of the most important drugs used to treat AML, but it does not work for everyone. About one-third of patients never respond to venetoclax-based treatment, while many others initially respond but eventually relapse as their cancer develops ways to resist the drug. Once venetoclax stops working, patients face an extremely poor prognosis, with median survival of just 1–3 months.
Zelenirstat is being developed to address this critical gap. It is designed to overcome the mechanisms that allow cancer cells to become resistant to venetoclax and to work synergistically with the drug, potentially restoring its effectiveness in patients who have otherwise lost the ability to benefit from it.
The immediate goal is to develop a convenient, all-oral combination therapy that could provide a new treatment option for patients with venetoclax-resistant AML – one of the most urgent unmet needs in leukemia today.
Importantly, the opportunity may extend well beyond AML. The biology underlying zelenirstat could have applications across multiple cancers, making Pacylex’s technology potentially a broader platform for overcoming cancer treatment resistance, rather than a single-cancer drug.
The immediate milestone is a Phase 2a clinical trial in patients with resistant AML.
We plan to enroll 20 patients whose AML has returned or stopped responding to venetoclax. Patients will receive zelenirstat in combination with venetoclax. The goal is to demonstrate meaningful clinical benefit in at least 20% of patients, an important signal that the combination can overcome resistance and warrants further development.
Preclinical studies have shown that zelenirstat can address multiple mechanisms by which cancer cells become resistant to venetoclax and can work powerfully in combination with the drug.
At the same time, we are advancing a second opportunity: next-generation molecules for antibody-drug conjugates (ADCs). ADCs are targeted cancer medicines designed to deliver a powerful cancer-killing agent directly to tumor cells while limiting exposure to healthy tissue. Our next-generation molecules have demonstrated up to 10-fold greater potency in preclinical studies.
We are meeting with major life science investors and pharmaceutical companies about funding our Phase 2a trial of zelenirstat in leukemia patients combined with another widely used oral drug, venetoclax, with which it synergizes. But a large investment or partnership takes time to put together. Meanwhile we need to get ready to conduct the study to make sure there is no delay in treating patients. We need to raise up to $500,000 to:
In parallel with pursuit of strategic partnerships with pharmaceutical and biotechnology companies, we are also listed with a venture philanthropy fund and have been in discussions with Blood Cancer United (formerly the Leukemia & Lymphoma Society) regarding potential support for the clinical trial, with grants of up to $500,000.
This funding would give us the resources to get zelenirstat ready to put to the test in patients who have exhausted an important treatment option, while simultaneously advancing the broader potential of the technology.
We have already assembled much of the infrastructure needed to launch the clinical trial. The principal investigator, clinical sites and clinical research organization (CRO) have been identified, and all have prior experience with zelenirstat through participation in the Phase 1 study or other Pacylex programs.
This experience gives the team a significant head start and reduces both execution risk and the time required to initiate the study.
We will maintain a lean operating model, adding only the clinical, regulatory and financial management expertise needed to execute the program.
Importantly, we already have a supply of the drug. The remaining manufacturing requirement is primarily to produce and label the capsules specifically for this clinical trial, allowing us to move efficiently toward patient enrollment once funding is secured.
The loss of Pacylex would mean more than the loss of a single drug program. Pacylex is pioneering a new approach to cancer biology, and if the company cannot secure the funding needed to advance its work, patients could lose access to a promising new treatment approach for years, or potentially decades.
In AML alone, an estimated 30,000 patients each year could face a lack of effective options after becoming resistant to existing therapies.
But the potential impact goes much further. The company’s compounds may have applications in preventing resistance to immune checkpoint inhibitors, which are used to treat hundreds of thousands of cancer patients, and in enhancing the effectiveness of radiation therapy.
That makes Pacylex’s technology potentially much more than a treatment for one difficult-to-treat blood cancer. It could represent a new platform for overcoming treatment resistance and improving the effectiveness of cancer therapies across multiple diseases.
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Cheif Executive Officer
Dr. Weickert has been developing drugs at public and private companies for over 30 years. He has been CEO of Fe Pharmaceuticals, illumiSonics, Sonescence, and SEA Medical Systems, CBO of Strategent Life Sciences, Corium, and Therashock, COO of Greenfire Bio and Ohm Oncology, VP of development at SciDose and Auspex, and Senior Program Executive or Manager at Nektar and Ligand. Michael has driven oncology product development including Phase III/NDA for Targretin for Cutaneous T-cell Lymphoma, and business planning for drug delivery versions of the cancer drugs Leuprolide, Paclitaxel and Irinotecan. He obtained Orphan Drug and Fast Track designations for oncology-related products in the US and EU. Prior to joining the pharmaceutical industry, he was at the National Cancer Institute at NIH. He has a PhD in Genetics from the University of Wisconsin, Madison.
Chief Scientific Officer
Luc is a professor of cell biology at University of Alberta with 28 years of experience studying protein fatty acylation. He received his PhD from the Université de Sherbrooke and completed his Post-Doctoral Fellowship at the Memorial Sloan-Kettering Cancer Centre. He has more than 40 publications and 3 patents published or pending. Luc is also the founder and president of Eusera, an antibody manufacturing company in Edmonton, AB, which produces and markets many commercially successful antibodies.
VP Operations
Ryan has a background in research, technology commercialization, business development, and financing early stage companies. Ryan has provided business planning and company development for many early-stage, technology-based ventures in health-related fields in his previous positions as the Director of the Merck Invention Accelerator, with the University of Alberta, TEC Edmonton, and as an independent consultant. He also has nearly a decade of experience in the angel investing space as a Co-Founder and investor in Valhalla Private Capital. He holds a Masters in Experimental Oncology and an MBA from the University of Alberta.