FDA Grants Cantrixil Orphan-Drug Designation for Acute Myeloid Leukemia
Key Facts
Vivesto said on 3 November 2026 that the U.S. Food and Drug Administration had granted Cantrixil orphan-drug designation for the treatment of acute myeloid leukemia. The decision marks a regulatory step in the drug’s development for this indication, while Cantrixil remains in preclinical development. The company’s chief executive, Erik Kinnman, said the designation “strengthens the basis for advancing Cantrixil toward a Phase 1 study” for the disease. Vivesto did not announce that the study had begun. The announcement came as the company estimated, based on statistics from the U.S. National Cancer Institute, that 22,720 people in the United States would be diagnosed with the disease during 2026 and that about 11,500 would die from it.
Vivesto said preclinical results showed Cantrixil had anticancer activity both as a standalone treatment and in combination with existing therapies. On 4 November 2025, the company reported positive results from preclinical studies in an animal model of acute myeloid leukemia. It said at the time that the effect was stronger when the drug was combined with other anticancer medicines. These results remain at the preclinical stage, while the announced development plan is moving toward a Phase 1 human study. On 16 June 2026, the company said results from a pharmacokinetic and toxicology study in dogs supported continued development of the drug toward that study in patients with the disease.
The dog study was part of the preclinical program for the intravenous drug and involved four animals given escalating doses in three rounds at 2, 5 and 10 mg per kilogram. Vivesto said Cantrixil was well tolerated at all dose levels, with no adverse findings or cardiovascular effects. On 13 March 2026, the company had announced that four dogs would be included in the study and that results were expected in the summer of that year. In June, it said the data supported completion of the preclinical package needed to prepare for the human trial. Kinnman described the results as a basis for continuing preparations for a Phase 1 study, without announcing a start date.
The U.S. Food and Drug Administration defines a rare disease, for orphan-drug designation purposes, as a disease or condition affecting fewer than 200,000 people in the United States. The designation provides potential incentives, including tax credits for eligible clinical trials and exemptions from certain regulatory application fees. The drug may also qualify for seven years of U.S. market exclusivity if it later receives marketing approval for the specified indication and meets the requirements. The agency says designation is separate from an application for approval or licensing, and designated drugs undergo scientific review like other drugs. Cantrixil’s designation therefore does not constitute marketing approval or establish its safety or effectiveness for treating acute myeloid leukemia.
Cantrixil has an earlier regulatory record related to ovarian cancer: the FDA’s register lists a designation for that indication dated 20 April 2015. The public register indicates that the drug is not FDA-approved for that orphan indication. Vivesto’s announcement on 3 November 2026 concerns a designation for the treatment of acute myeloid leukemia. The public register does not show the AML designation cited in the company’s announcement. Vivesto says the drug previously underwent a Phase 1 study as part of its development program for ovarian cancer, while the company currently describes it as being in preclinical development for acute myeloid leukemia.