Real-World Study of Adjuvant Biosimilar Trastuzumab-dkst for HER2-Positive Breast Cancer Treatment in a Brazilian Population.

INTRODUCTION: Biological monoclonal antibodies play a pivotal role in cancer treatment, with biosimilars significantly enhancing their accessibility. In Brazil's ethnically diverse setting, real-world evidence is crucial for assessing the effectiveness and applicability of these therapies in routine clinical practice. METHODS: We performed a multicentric, observational, prospective real-world study on biosimilar trastuzumab-dkst for adjuvant treatment of early HER2-positive breast cancer in Brazilian patients. Data were collected using a case-report form. RESULTS: Of the 176 recruited, we present data from the first 59 patients (mean age 51.7 ± 12.9 years) who had completed treatment with trastuzumab-dkst. The mean time from diagnosis to the first adjuvant treatment with trastuzumab-dkst was 5.5 ± 2.7 months. Of the patients, 59% of patients achieved at least a 30-month follow-up. The 31.7-month invasive disease-free survival rate (IDFS) was 94.5% (95% CI 83.9-98.2%) and median IDFS was not achieved, since only three patients had invasive disease recurrence. The overall survival rate was 100% until the last assessment. The observed adverse events were similar to those presented by other studies using biosimilar or reference trastuzumab. Four serious adverse events (8.5%) were observed. A reduction in left ventricular ejection fraction of at least 10% was observed in 16.9% of participants. There was no treatment interruption, and three participants (5.1%) had their trastuzumab-dkst dose reduced. CONCLUSION: Our study reinforces the existing pivotal data, underscoring the real-world efficacy and safety of biosimilar trastuzumab-dkst in the adjuvant treatment for early HER2-positive breast cancer. The preliminary long-term effectiveness and safety data we present further validate trastuzumab-dkst's role as a cost-saving alternative in oncological care. These findings have important implications for improving patient access to crucial treatments and for the more efficient use of healthcare resources. GOV REGISTRATION: NCT03892655.

Factors influencing COVID-19 mortality among cancer patients: A Brazilian multi-institutional study.

PURPOSE: This study aimed to describe the demographic and clinical characteristics of cancer patients with COVID-19, exploring factors associated with adverse outcomes. PATIENTS AND METHODS: This retrospective cohort study methodically extracted and curated data from electronic medical records (EMRs) of numerous healthcare institutions on cancer patients diagnosed with a confirmed SARS-CoV-2 infection between May 2020 and August 2021, to identify risk factors linked to extended hospitalization and mortality. The retrieved information encompassed the patients' demographic and clinical characteristics, including the incidence of prolonged hospitalization, acute complications, and COVID-19-related mortality. RESULTS: A total of 1446 cancer patients with COVID-19 were identified (mean [Standard deviation] age, 59.2 [14.3] years). Most patients were female (913 [63.1%]), non-white (646 [44.7%]), with non-metastatic (818 [56.6%]) solid tumors (1318 [91.1%]), and undergoing chemotherapy (647 [44.7%]). The rate of extended hospitalization due to COVID-19 was 46% (n = 665), which was significantly impacted by age (p = 0.012), sex (p = 0.003), race and ethnicity (p = 0.049), the presence of two or more comorbidities (p = 0.006), hematologic malignancies (p = 0.013), metastatic disease (p = 0.002), and a performance status ≥ 2 (p = 0.001). The COVID-19-related mortality rate was 18.9% (n = 273), and metastatic disease (<0.001), performance status ≥2 (<0.001), extended hospitalization (p = 0.028), renal failure (p = 0.029), respiratory failure (p < 0.001), sepsis (p = 0.004), and shock (p = 0.040) significantly and negatively influenced survival. CONCLUSION: The rate of extended hospitalization and COVID-19-specific death in cancer patients was notably high and could be influenced by comorbidities, cancer treatment status, and clinical fragility. These observations may aid in developing risk counseling strategies regarding COVID-19 in individuals diagnosed with cancer.

A phase III, randomized, non-inferiority study comparing the efficacy and safety of biosimilar filgrastim versus originator filgrastim for chemotherapy-induced neutropenia in breast cancer patients

OBJECTIVES: To compare the efficacy and safety of two filgrastim formulations for controlling chemotherapy-induced neutropenia and to evaluate the non-inferiority of the test drug relative to the originator. METHODS: This phase III non-inferiority study had a randomized, multicenter, and open-label design. The patients were randomized at a ratio of 1:1 with a follow-up period of 6 weeks for each patient. In both study arms, filgrastim was administered subcutaneously at a daily dose of 5 mg/kg body weight. The primary endpoint was the rate of grade 4 neutropenia in the first treatment cycle. The secondary endpoints were the duration of grade 4 neutropenia, the generation of anti-filgrastim antibodies, and the rates of adverse events, laboratory abnormalities, febrile neutropenia, and neutropenia of any grade. RESULTS: The primary efficacy analysis demonstrated the non-inferiority of the test drug compared with the originator drug; the upper limit of the 90% confidence interval (CI) for the rate of neutropenia between the two groups (12.61%) was lower than the established margin of non-inferiority. The two treatments were similar with respect to the secondary endpoints and safety. CONCLUSION: The efficacy and safety profile of the test drug were similar to those of the originator product based on the rate of grade 4 neutropenia in the first treatment cycle. This study supports Anvisa’s approval of the first biosimilar drug manufactured by the Brazilian industry (Fiprima¯).