Long-term data from ACE-CL-001 further supports the favorable results of acalabrutinib in phase III studies for patients with symptomatic, treatment-naïve chronic lymphocytic leukemia (CLL).
Results of the study were presented at the American Society of Clinical Oncology (ASCO) Annual Meeting (May 29-31, 2020).
Acalabrutinib was recently approved in patients with treatment-naïve, relapsed or refractory CLL based on two complimentary phase III studies: ELEVATE-TN and ASCEND. The phase II ACE-CL-001 study provides the longest safety and efficacy and follow-up to date of acalabrutinib in symptomatic, treatment-naïve patients with CLL.
Ninety-nine patients were included in the study who met iwCLL 2008 criteria for treatment, were inappropriate for or declined standard chemotherapy, and had an ECOG performance score of 0 to 2. Patients received acalabrutinib 100 mg BID (n = 62) or 200 mg QD with a later switch to 100 mg BID (n = 37) until progressive disease or unacceptable toxicity.
The primary endpoint of the study was safety, with additional endpoints of investigator-assessed overall response rate, duration of response, time to response, and event-free survival. Events of clinical interest were based on combined adverse event terms for infections, bleeding events, hypertension, and secondary primary malignancies.
After a median follow-up of 53 months, 86% (n = 85) of patients remained on treatment. Most discontinuations were due to adverse events or progressive disease. Among the most common adverse events of any grade were diarrhea (52%), headache (45%), upper respiratory tract infection (44%), arthralgia (42%), and contusion (42%). All-grade and grade 3 or higher events of clinical interest included infection (84% and 15%, respectively), bleeding events (66% and 3%, respectively), and hypertension (22% and 11%, respectively).
Additionally, researchers found that overall response rate was 97% and the median time to response was 3.7 months. Response rates were similar across high-risk groups. The median duration of response and event-free survival were not reached; the 48-month duration of response rate was 97%, and the 48-month event-free survival rate was 90%.
“Long-term data from ACE-CL-001 further support the favorable results with acalabrutinib in phase III studies and demonstrate durable responses with no new long-term safety issues,” authors of the study concluded.—Zachary Bessette
