Infusion reactions and effectiveness of front-line obinutuzumab and chlorambucil for chronic lymphocytic leukemia

This study aimed to investigate infusion reactions and the effectiveness of the combination of obinutuzumab (Gazyva) and chlorambucil (Leukeran) in patients with chronic lymphocytic leukemia (CLL). 

This study concluded that first dose infusion reactions with obinutuzumab can be reduced by using chlorambucil first and by using a very slow initial obinutuzumab dose. 

Patients with chronic lymphocytic leukemia (CLL) have had improved survival and response rates when treated with obinutuzumab (Obi). Obi is an immunotherapy drug that activates the immune system leading to cancer cell death. The combination of Obi and chlorambucil (Chl) is the current front-line treatment for patients with CLL due to very good results in clinical trials.

However, infusion reactions have been a concern for Obi treatment. Therefore, it is important to evaluate Obi-Chl treatment in patients with CLL in a real-world practice. 

This study involved data from 142 patients with CLL who received a front-line treatment. 47% of patients received Obi-Chl and 53% were treated with other front-line therapies.   

Overall, 43.4% of patients on Obi-Chl had infusion-related reactions (IRRs). Most of these were mild when Chl was administered first. 6% of patients had severe Obi (IRR) compared to 20% for a previous CLL11 clinical trial. The lower rate of IRR was due to slower infusion rates and using Chl before starting Obi treatment.  

Many patients had difficulty tolerating a full dose of Chl.  

Overall, 76.1% of patients had a hematologic response (normalization of blood cell counts). After 35 months, approximately 80% of patients on Obi-Chl were alive. 

This study concluded that first-line treatment with Obi-Chl is a good choice, particularly for older patients with CLL. Also, first dose infusion reactions with obinutuzumab can be reduced by using chlorambucil first and by using a very slow initial obinutuzumab dose. 

This study was based on medical records and included a very small number of participants. Larger studies are needed to confirm these results.