Filgrastim Biological Shows Similar Efficacy to Originator
A clinical study comparing two formulations of filgrastim for controlling chemotherapy-induced neutropenia has shown that the efficacy and safety profile of the test drug were similar to those of the originator product.
Neutropenia is one of the most common chemotherapy-related adverse events, and in severe cases, places patients at high risk of serious infection with a mortality rate of 10%. Neutropenia may lead to decreased dosages and reduce the effectiveness of treatment, as well as increase the cost of breast cancer treatment.
The patients in the phase III non-inferiority clinical drug trials were randomised at a ratio of 1:1, with a follow-up period of 6 weeks allocated for each patient. The drug trials had a randomised, multicentre and open-label design and involved filgrastim being administered subcutaneously for each patient at a daily dose of 5 mg/kg body weight in both study arms.
The primary endpoint of the clinical trial was the rate of grade 4 neutropenia in the first treatment cycle, and the secondary endpoints included the rates of neutropenia, the duration of grade 4 neutropenia, the generation of anti-filgrastim antibodies, and the frequency of adverse events and laboratory abnormalities.
The study showed that the primary efficacy analysis demonstrated the non-inferiority of the test drug compared with the originator drug, as the upper limit of the 90% confidence interval for the rate of neutropenia between the two groups (12.61%) was lower than the established margin of non-inferiority. The authors of the study also reported that the two treatments were similar with respect to the secondary endpoints and safety.
In conclusion, the efficacy and safety profile of the test drug were similar to those of the originator product, further improving medicine access for those with breast cancer. This conclusion was made by the authors based on the rate of grade 4 neutropenia in the first treatment cycle.