BioCentury
ARTICLE | Clinical News

Oral anti-neoplastic drugs cancer data

March 26, 2012 7:00 AM UTC

Researchers at Medco Health conducted a retrospective analysis of its pharmacy claims database showing that 23-74% of about 11,600 patients who were prescribed 1 of 9 oral OADs between January 2008 and May 2010 were also receiving a drug that had the potential to reduce effectiveness or increase toxicity of the OAD. Specifically, 43% of patients who received imatinib in the analysis (n=4,617) were also prescribed a drug that could impair the cancer drug's efficacy, while 68% also received a drug that could increase imatinib's toxicity. In patients who received the other 8 OADs included in the analysis, 23-57% were prescribed a drug that could impair efficacy of the OADs, while 24-74% received a drug that could increase the toxicity.

Co-prescription was defined as >=1 overlapping day of supply with the OAD. Medications with potential for drug-drug interactions that induce or inhibit CYP450 pathways and the P-glycoprotein transporter used by the OADs were identified from labels of the cancer products and other published sources. Medco said that medications that may cause drug-drug interactions include proton pump inhibitors (PPIs), steroids, calcium channel blockers and certain antibiotics and antifungal agents. Drug-drug interactions were categorized as either potentially reducing OAD effectiveness or increasing toxicity. Data were presented at the American Society for Clinical Pharmacology and Therapeutics meeting in National Harbor. ...