Blogger Pieter Droppert reports details this morning on drug giant AbbVie's ($ABBV) suspension of multiple clinical trials for an experimental leukemia drug code-named ABT-199, writing that a "reliable" source tells him that the trials were halted after the death of a patient in a study. The company confirmed for FierceBiotech this afternoon that two patients in the program died.
In an interview with FierceBiotech, AbbVie spokeswoman Tracy Sorrentino clarified that new patient enrollment and dose-escalation of the compound were suspended in trials weeks ago after the patient deaths, but that the studies were ongoing with previously enrolled patients. The suspensions were voluntary, she said, and the company expects to resume enrollment in the studies and advance the program into Phase III development as expected later this year. AbbVie, which is the new spinoff of Abbott Laboratories' ($ABT) pharma business, is partnered with Roche's ($RHHBY) Genentech on the program.
As Droppert writes on his "Biotech Strategy Blog," AbbVie suspended trials of ABT-199, an experimental BCL-2 inhibitor drug in development for chronic lymphocytic leukemia, ahead of planned late-stage studies. And his source says that the patient death in a trial was due to a condition known as tumor lysis syndrome. Sorrentino said that both patients died from the condition, which can result when the broken-up parts of dead cancer cells thrash the liver and kidneys, often after cancer treatment.
Droppert's colleague Sally Church wrote that ABT-199 could resume development after the company adjusts the dosing, and that insight appears to be spot on, as Sorrentino explained that the plan is to refine dose-escalation plans to avoid adverse effects. So there's a chance that AbbVie still has a viable candidate.
AbbVie holds claim to one of the best-selling drugs in the world in Humira, a drug against autoimmune diseases, yet the company has no other products that come close to generating as much revenue, and patents on the megablockbuster expire in 2016. That puts pressure on AbbVie to generate new drugs from its R&D pipeline, which appears to have popped a leak as far as ABT-199 is concerned. Yet perhaps not as much of a leak as might have appeared before the company clarified the status of the program.
"This is a highly effective agent that can result in rapid tumor reduction," Sorrentino said in a phone interview. "We continue to see this as a very promising compound. We have every expectation that the trials will come off of clinical hold and that we'll be able to initiate Phase III trials. This doesn't dim our enthusiasm in any way."
Editor's note: Updated with comments from AbbVie.