This was a gutsy trial, a first of its kind head-to-head comparison between two Bruton Tyrosine Kinase (BTK) inhibitors, acalabrutinib and ibrutinib for bragging rights as to who was the best in class for treating chronic lymphocytic leukemia patients.
Here is the lead from the press release from AstraZeneca, maker of acalabrutinib:
“Positive high-level results from the ELEVATE-RR Phase III trial showed AstraZeneca’s CALQUENCE® (acalabrutinib) met the primary endpoint demonstrating non-inferior progression-free survival (PFS) for adults with previously treated, high-risk chronic lymphocytic leukemia (CLL) compared to ibrutinib”.
Noninferiority trials test whether a new experimental treatment is not unacceptably less effective than an active control treatment already in use.
And in this case, it wasn’t. In other words, how long patients lived without their CLL progressing was similar with both drugs.
The trial also met a key secondary endpoint when after more than 40 months of study they found that patients treated with acalabrutinib had statistically significantly lower incidence of atrial fibrillation (AF) compared to patients treated with ibrutinib.
AF is a potentially dangerous irregular heart rate and rhythm that can be seen with ibrutinib, and to a lesser extent, with acalabrutinib treatment as shown in this trial.
Otherwise, the two drugs were pretty similar in their profiles.
It’s only a press release, and we need to wait to see all the data, but it is encouraging. It does suggest that high risk relapsed and refractory CLL patients can feel comfortable with having two powerful proven BTK options and they don’t have to sacrifice efficacy for safety in their disease management.
And that is good news.
Here is the press release:
Stay strong, we are all in this together.
Brian Koffman