Estudio observacional de la toxicidad con diferentes formulaciones de docetaxel en pacientes con cáncer de mama./ Observational study of clinical toxicity with different formulations of docetaxel in breast cancer patients.

OBJECTIVE: To analyze the excipients and impurities contained in the various docetaxel products available on the market and find out  whether they may be responsible for any of the different adverse events  associated with the use of docetaxel in patients with breast cancer  receiving adjuvant or neoadjuvant treatment. METHOD: This is a prospective, multicenter, longitudinal observational, study carried in 26 hospitals in Madrid, Catalonia, Andalusia, and the Valencia Region. The different docetaxel formulations were  characterized in terms of their pH, amount of the active ingredient and  impurities. The cumulative incidence of adverse events of any grade was  evaluated. Adverse events were stratified by drug type and differences  were analyzed by means of a chi-square test. RESULTS: Statistically significant differences were found between the different docetaxel formulations in the cumulative per-cycle incidence of: dosage change, anemia, hypersensitivity reactions and  anaphylaxis, neuropathy, palmoplantar and dermal toxicity, ungual toxicity  and facial edema. The formulation with the lowest content of impurities  showed better results in terms of change of dosage, visits to the  emergency room and incidence of anemia and facial edema. However, it  was associated with poorer results regarding hospitalization, febrile  neutropenia, motor neuropathy and palmoplantar toxicity. CONCLUSIONS: The results of the study showed differences in the incidence of adverse events of the different docetaxel products available in  Spain. Such differences were statistically significant for some of the  variables analyzed. The study was not able to determine which of the  products offered the best toxicity profile. Nor was it possible to establish a  correlation with respect to the composition of excipients or the content of  impurities.