The Seattle biotech announced that the trial of pacritinib had been halted on February 9 after the US Food and Drug Administration (FDA) imposed a clinical hold.
The firm – which also withdrew the New Drug Application (NDA) for the drug – explained that the suspension followed several patient deaths.
The study - known as PERSIST-2 - is examining whether once-daily or twice-daily pacritinib results in a greater proportion of patients with thrombocytopenia and myelofibrosis achieving ≥ 35% reduction in spleen volume from baseline.
CTI said: "The deaths in PERSIST-2 in pacritinib-treated patients include intracranial hemorrhage, cardiac failure and cardiac arrest."
Multi-national trial
The drug is being tested at sites in the US, Australia, Belgium, Canada, the Czech Republic, France, Germany, Hungary, the Netherlands, New Zealand, Russia and the UK.
The trial has enrolled 300 people according to the latest information on US trial registry, clinicatrials.gov.
A spokeswoman for CTI told us “We worked with a CRO as well as an in-house team” but declined to identify the contractor in question on the basis that “they would not want to be named.”
She also confirmed that the study had been halted at sites in the US and overseas, telling us that: “Last week, an email was sent immediately and we held a series of webcasts over several days for all of the multinational sites to attend."
CTI BioPharma is planning to commercialize pacritinib with Baxalta - previously known as Baxter International - which licensed rights to the drug in 2013 for $60m upfront and an agreement to pay milestones of up to $112m.
A post on a myeloproliferative neoplasms website lists an Ockham employee as the contact for the earlier PERSIST-1 study.
Cancer-focused Ockham was bought by Chiltern International in 2014. Chiltern did not respond when we asked if it is involved in PERSIST-2.