Purpose: The aim of this study was to test the feasibility and the usefulness of an intensive safety monitoring program to identify adverse drug reactions for medicines under additional monitoring that are used to treat cancer patients within a Portuguese oncology hospital.
Methods: This pilot intensive safety monitoring program was a three-month prospective, observational study. Patients undergoing treatment with one of the following medicines were included: nivolumab, olaparib, palbociclib, pembrolizumab, pertuzumab, ramucirumab, ribociclib, trastuzumab emtansine, or trifluridine/tipiracil. Potential eligible patients were identified by pharmacists based on prescription data. Clinicians used proper paper-based reporting forms to record adverse drug reactions. Clinical secretariats sent those reports through an electronic platform to the pharmacovigilance department for analysis.
Results: Seventy-five patients were on treatment with selected medicines. Of those, 33 (44%) experienced adverse drug reactions: 23 (69.7%) cases were serious and 5 (15.2%) unexpected. Considering the number of patients exposed to each medicine and the number of patients experiencing adverse drug reactions, trifluridine/tipiracil (72.7%; 8/11) was associated with the highest rate of toxicity, followed by olaparib (66.7%; 2/3), trastuzumab emtansine (50.0%; 3/6), pertuzumab (47.8%; 11/23), pembrolizumab (45.5%; 5/11), palbociclib (25.0%; 1/4), and nivolumab (18.8%; 3/16). A total of 59 adverse drug reactions were identified (i.e. 1.8 adverse drug reactions/patient), mainly gastrointestinal disorders (n = 15; 25.4%), and blood and lymphatic system disorders (n = 14; 23.7%).
Conclusion: This intensive safety monitoring program was feasible and allowed identifying serious and unexpected adverse drug reactions, adding value to pharmacovigilance and therefore contributing to improve patient safety. Further research is needed to confirm the findings of this pilot study.
Keywords: Adverse drug reactions; chemotherapy; intensive monitoring; oncology; pharmacovigilance.