Researchers found that a reduction from weekly to biweekly administration in the maintenance dose schedule for cetuximab reduced the number of toxicities patients experienced during the study period. As a result, they said, this type of reduction could increase patient compliance to the medication and patient quality of life (QoL).
Although the researchers cited prior studies that have shown cetuximab is effective in the maintenance setting for other types of cancers, little is known about which schedule is optimal for head and neck cancers.
In the study, published in Oncology, the investigators looked at patients from a single institution from October 2016 to November 2017 with recurrent and/or metastatic squamous cell carcinoma of the head and neck (R/M SCCHN) who had received prior platinum-based chemotherapy plus cetuximab and who were considered to have stable disease after the end of treatment.1
From these cases, 36 patients were selected to receive biweekly cetuximab at 500 mg/m2 over 3 hours on day 1 and day 15 of each 28-day cycle (Group A). They were compared with a historical group of patients who had a standard weekly dose of 250 mg/m2 over 2 hours from August 2015 to September 2016 (Group B).
Of the 36 patients in Group A, 26 had previously received chemotherapy with cetuximab plus cisplatin and 5-fluoruracil and 10 had been administered cetuximab plus carboplatin and 5-fluoruracil — but 4 of the patients given the regimen with cisplatin were switched to the other carboplatin. Three patients in Group B who could not tolerate cisplatin also made this switch.
The overall response rate (ORR) in Group A was found to be 19% compared with 17% in Group B. Median progression-free survival (PFS) in Group A compared with Group B was 4.8 months and 4.4 months, respectively, and overall survival was 9 months and 7.9 months, respectively.
Although the authors admitted they did not perform a statistical analysis between the study groups in comparing the adverse effects the patients experienced — meaning, there were no measures of statistical significance calculated assessing the differences in adverse events between the groups — “showed superimposable adverse events.” Dose delays as a result of skin toxicities occurred in 3 patients in Group B and 7 patients in Group A.
Patients were more adherent to their treatment regimen in Group A compared with patients in Group B; infusions were completed in 95% of patients in Group A and in 88% of the patients in Group B.
The study, according to authors, “promotes the idea” that changing the dose schedule of cetuximab for maintenance purposes from weekly to biweekly administration improves patient adherence and QoL. “The feasibility and safety of the biweekly schedule were confirmed with data concerning the delay of infusions related to the toxicity [in Group B],” they added.
- Addeo R, Montella L, Mastella A, et al. Maintenance therapy with biweekly cetuximab: optimizing schedule can preserve activity and improves compliance in advanced head and neck cancer [published online September 5, 2018]. Oncology. doi: 10.1159/000492153.