Evaluating acalabrutinib plus obinutuzumab in patients with chronic lymphocytic leukemia

This study evaluated the safety and effectiveness of the combination of acalabrutinib (Calquence) and obinutuzumab (Gazyva) in patients with chronic lymphocytic leukemia (CLL). The authors concluded that this combination was effective and well tolerated in patients with CLL.

Chronic lymphocytic leukemia (CLL) is a cancer of the bone marrow. It is often treated with drugs that target certain proteins on cancer cells. Obinutuzumab is a monoclonal antibody. Monoclonal antibodies attach directly to cancer cells to deliver treatments. Obinutuzumab can be used to treat CLL. Acalabrutinib is a kinase inhibitor. It works by blocking the action of the abnormal protein that signals cancer cells to multiply. This helps stop the spread of cancer cells. Acalabrutinib has been approved for the treatment of CLL.

However, the safety and effectiveness of acalabrutinib and obinutuzumab combined are still under investigation.

This study included 45 patients with CLL. Of these, 19 patients had never been treated (group 1). The other 26 patients had received previous therapies and had relapsed or unresponsive disease (group 2). All patients received acalabrutinib and obinutuzumab treatment during this study. Patients were followed up for an average of 39 (group 1) to 42 months (group 2).

The overall response rate was 95% for group 1 and 92% in group 2. 32% of group 1 and 8% of group 2 had no signs of cancer left after treatment (complete response).

In group 1, at the 39 months follow-up, all patients were alive and 94.4% of patients were alive with no disease progression. In group 2, at the 42 months follow-up, 82% of patients were alive and 72.7% were alive with no disease progression. 

The most common side effects reported were headache and infusion-related reactions. 63% of patients in group 1 and 77% of those in group 2 had experienced severe side effects. These included low white blood cell counts (24%), loss of consciousness (11%), low platelet count (9%), and high blood pressure (7%).

The authors concluded that the combination of acalabrutinib and obinutuzumab was effective and well tolerated in patients with CLL. 

This study had a small number of participants. Larger studies are necessary for stronger evidence. This study received funding from Acerta Pharma, a member of the AstraZeneca Group, the manufacturer of acalabrutinib.