Serious safety issue forces Novo Nordisk to hit pause on late-stage hemophilia trials

Novo Nordisk has halted one midstage and two late-stage tests of its bleeding disease drug concizumab after seeing blood clots in some patients.

The Danish pharma, more known for its diabetes franchise, has been branching out more deeply into hemophilia in the past few years, following a growing market for the bleeding disease. This includes the recent approval for its hemophilia A drug Esperoct and an R&D tie-up with Bluebird Bio for its gene therapy approach to the disease.

Concizumab is a key part of its hemophilia pipeline, but testing of the drug has now been paused, specifically two trials in its phase 3 program (known as explorer7 and 8) and one study in the phase 2 program (explorer5).

These were testing concizumab as a prophylactic treatment in both hemophilia A and B patients regardless of inhibitor status.

In a brief statement, the biopharma said: “The decision is a result of the occurrence of non-fatal thrombotic events in three patients enrolled in the ongoing phase 3 programme. Novo Nordisk and an independent Data Monitoring Committee are currently assessing the relevance of the events to the continuation of the programme and no conclusions have yet been made.”

It added that no extra patients will be recruited, and further treatment of patients currently enrolled in the trials with concizumab “will cease.”

“While it is disappointing to pause the trials, patient safety is of utmost importance to Novo Nordisk—both for those taking part in our clinical trials and those who use our products on a daily basis,” said Mads Krogsgaard Thomsen, executive vice president and chief science officer of Novo Nordisk. “Together with relevant authorities, we will now carefully evaluate all available data and decide how to best move forward.”