Diet and Dosage: How Much Could Patients Save?
Knowing that food increases the absorption of some therapies presents the possibility of easily — and significantly — lowering treatment costs.
The authors of a recent prostate cancer study claim that a drug manufacturer and the US Food and Drug Administration (FDA) ignored a chance to cut medication costs by disregarding the impact of food intake on drug absorption.
The study focused on abiraterone acetate, “the most widely prescribed first-line medication” for metastatic castration-resistant prostate cancer (mCRPC). But the authors raise questions about the possibility of slashing treatment costs with many more anticancer agents simply by focusing on the effect of dosing with meals as opposed to while fasting.
Remarkably, both the manufacturer and the FDA knew during the approval process that taking the drug with food led to an exponential increase in the medication's absorption.
“According to the drug label, food leads to a five- to seven-fold increase in drug concentration with a low-fat meal and a 10- to 17-fold increase with a high-fat meal,” the authors wrote.
As a result, the study found, patients taking one-fourth the recommended dosage with a low-fat meal instead of on an empty stomach realized a greater effect on prostate-specific antigen (PSA) response (58% vs 50%, respectively). The median progression-free survival was approximately 9 months for both groups.
“The pharmacoeconomic implications of this study's findings are compelling,” the authors wrote. “[Abiraterone acetate] has an approximate retail cost of $10,000 per month. With a median time receiving treatment of 16.5 months in metastatic CRPC, the per-patient cost savings with the LOW dosing would exceed $100,000.”
One of the study's authors, Mark Ratain, MD, director of the University of Chicago Medicine Center for Personalized Therapeutics and associate director for clinical sciences of its Comprehensive Cancer Center in Illinois, said abiraterone acetate is only one example of the potential of this food effect.
“There are many opportunities with oral oncology drugs to increase absorption with food,” he said. “We picked abiraterone just because it had a particularly large food effect and its formulation was such that we could readily do it. But it's not unique. And the data is hiding in plain sight, as they say.”
Food doesn't increase the absorption of every oral therapy. A 2014 review of known food and drug interactions on anticancer agents found that, in some cases, taking medications with high-fat meals could increase systemic exposure.2 A similar meal, though, could decrease uptake by as much as 50%, as is the case with afatinib, an EGFR inhibitor.