Premium
Drug–drug interaction potential in men treated with enzalutamide: Mind the gap
Author(s) -
Benoist Guillemette Emma,
Oort Inge M.,
Smeenk Stella,
Javad Adrian,
Somford Diederik M.,
Burger David M.,
Mehra Niven,
Erp Nielka P.
Publication year - 2018
Publication title -
british journal of clinical pharmacology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.216
H-Index - 146
eISSN - 1365-2125
pISSN - 0306-5251
DOI - 10.1111/bcp.13425
Subject(s) - medicine , enzalutamide , drug , prostate cancer , pharmacoepidemiology , pharmacodynamics , cohort , pharmacy , retrospective cohort study , pharmacology , pharmacokinetics , emergency medicine , cancer , medical prescription , family medicine , androgen receptor
Aims Metastatic castration‐resistant prostate cancer (mCRPC) patients are generally older patients with several co‐morbidities and are therefore at increased risk of complications due to drug–drug interactions (DDIs). We assessed the prevalence of potential DDIs in a cohort of mCRPC patients treated with enzalutamide. Methods We conducted a retrospective review of pharmacy records to retrieve individual drug histories of mCRPC patients who started enzalutamide therapy in a tertiary care setting. Potential DDIs were analysed using two international drug interaction compendia: Lexicomp ® and Micromedex ® , and the Dutch drug database. Two potential pharmacodynamic DDIs were analysed. Results A total of 105 records were evaluated for potential DDIs with enzalutamide. Of 205 different co‐medications, 56 were flagged by at least one of the three compendia: Lexicomp, Micromedex and the Dutch drug database flagged for potential DDIs in 85%, 54% and 32%, respectively. Eighty‐five per cent of DDIs were classified as major. The median number of co‐medications per patient was 11 (range 1–26). The median (range) number of interactions per patient was 4 (0–10), 1 (0–5) and 0 (0–2) for Lexicomp, Micromedex and the Dutch drug database, respectively. In 23% and 45% of all patients, a potential DDI was found with PPIs and CNS depressants, respectively. Conclusions A high prevalence of potential DDIs was found. The inclusion and grading of potential DDIs was highly variable between the three drug interaction compendia. Physicians, nurses and pharmacists should be aware of this potential problem, which might require intensive monitoring or alternative treatment strategies to prevent suboptimal treatment of the co‐morbidities in patients treated with enzalutamide.