Evaluation of the Adverse Effects of Monoclonal Antibodies in Breast Cancer Treatment in a Tertiary Care Hospital in Bengaluru, India, in 2020

Breast cancer (BC) is the leading cause of cancer mortality among women in different countries around the world, including India. Monoclonal antibodies (MoAbs) have emerged as a promising targeted treatment for BC, improving the survival rate of these patients with minimum adverse effects. This study aimed to investigate the severity of the adverse effects of MoAbs in an Indian population.

This longitudinal descriptive study was conducted on 120 BC patients over six months in a tertiary care hospital in Bangalore, India, in 2020. A data collection form was used to gather relevant data. The collected data were analyzed by SPSS Version 21, using Chi-square and Fisher’s exact tests. A P-value less than 0.05 was considered statistically significant.

Among 97 patients evaluated in this study (including 29 patients in the non-exposed group), the adverse effects of BC were observed in all age groups. Most adverse effects were attributed to trastuzumab (37.50%; CI: 31.6-44) and bevacizumab (26.78%; CI: 20.9-31.8). The MoAbs were well tolerated by the patients, causing minimum adverse effects that were manageable by supportive therapy. Anemia was the most prevalent adverse effect. Evaluation of the null hypothesis indicated that the adverse effects of MoAbs depended on their amount and composition. The results of analysis using the Naranjo scale revealed that most of the adverse effects were probable (67%) and possible (32%), respectively. Also, according to the WHO scale, most of the adverse effects were under the categories of probable (61.20%) and possible (38.14%), respectively.

Based on the present results, the adverse effects of MoAbs were manageable by supportive care. Anemia was found to be the most prevalent adverse effect. Meanwhile, no potential adverse cardiovascular event was observed in patients on trastuzumab, except one case of dilated cardiomyopathy.