The designation applies to AKY-1189 in patients who progressed after prior treatments, including those who progressed after Padcev.

The program carries forward-looking statements about development timelines and regulatory milestones, with cautions about risks and the need to rely on SEC filings for formal risk disclosures.

The trial investigates AKY-1189 across multiple Nectin-4–expressing tumors, including urothelial, breast, non-small cell lung, colorectal, cervical, and head and neck cancers.

The press release notes forward-looking statements and outlines risks related to trial timing, regulatory approvals, manufacturing of actinium-225, financial considerations, and intellectual property, advising investors to review SEC filings for formal risk disclosures.

Aktis Oncology announced that the U.S. FDA granted Fast Track designation to AKY-1189 for adults with locally advanced or metastatic urothelial cancer that progressed after prior systemic therapies.

Fast Track is intended to speed development and FDA review, with potential for more frequent interactions and rolling submissions for a biologics license application.

Aktis is conducting a multi-site Phase 1b trial of AKY-1189 in urothelial cancer and other Nectin-4–expressing tumors, with preliminary data from Part 1 anticipated in the first quarter of 2027.

AKY-1189 is a miniprotein radioconjugate designed to deliver actinium-225 to Nectin-4–expressing tumors, targeting urothelial cancer where Nectin-4 expression is high (about 80–90%).

Aktis emphasizes an isotope-agnostic radioconjugate platform that aims for high tumor penetration and rapid clearance from normal tissue, with imaging capabilities to verify target engagement before therapy.

The platform enables imaging to confirm target engagement and uses radioconjugates that can be matched to different isotopes for therapeutic delivery.

In addition to AKY-1189, Aktis is advancing AKY-2519, a second B7-H3–targeting radioconjugate, and maintains an ongoing collaboration with Eli Lilly to expand radioconjugate development beyond its core programs.

Aktis completed an upsized January 2026 IPO, raising about $365 million gross, with equity support noted from Vida Ventures and a collaboration with Eli Lilly valued up to $1.2 billion.