Kiadis dumps phase 3 drug, halves head count in pivot to NK cells

Kiadis has dropped its lead program midway through a phase 3 trial. The action will see Kiadis lay off half of its staff and switch its attention to earlier-stage natural killer (NK) cell therapies against solid tumors and hematological cancers.

Amsterdam-based Kiadis has focused its attention on lead drug ATIR101 for years, hustling the T-cell immunotherapy through the clinic with a view to winning conditional approval in Europe in patients undergoing transplantation with genetically half-matched hematopoietic stem cells in 2019. That goal, which had slipped to 2020, evaporated last month when Kiadis braced investors for a regulatory rejection.

Now, Kiadis has killed off ATIR101 altogether by scrapping the phase 3 trial designed to generate data to support a full approval. Kiadis took the action after an unexpectedly high dropout rate in the ATIR101 arm led it to look into real-world outcomes achieved by post-transplant cyclophosphamide, the control in the phase 3. The data dive led Kiadis to conclude the trial is unlikely to succeed. At best, a much larger trial would be needed to show ATIR101 is effective.

Kiadis’ action came as a shock to analysts. 

“The decision to terminate ATIR101 in the midst of its phase 3 comes as a surprise, even given recent EU regulatory setbacks,” analysts at Jefferies wrote in a note to investors.

Kiadis’ decision will cost half its employees their jobs. The Dutch biotech had begun preparing for the European launch of ATIR101, including by adding production capacity in Amsterdam, before learning regulators were set to reject the drug. Now, Kiadis again finds itself years from the market, ending its need for some of the capabilities it built up to support the push to commercialize ATIR101.

The remaining employees at Kiadis will focus on NK cell therapies. Kiadis moved into the NK space earlier this year through the acquisition of Cytosen Therapeutics. The deal gave Kiadis control of two NK cell therapy candidates it plans to test in phase 1/2 trials starting next year. 

Kiadis ended the third quarter with €47 million ($52 million) in cash to fund the studies, but the Jefferies analysts think that may run out before data from the NK trials are available. With shares in Kiadis falling 33% following news of the changes and Jefferies identifying the “dent to management credibility” as an overhang, the biotech’s ability to raise more cash may be weakened by the pivot.