New Study Examines Overspending on Oversized Cancer Drug Vials

A new study published in BMJ argues that the cost of oversized single dose vials of cancer drugs may be causing patients to overpay for unused medicine.

The study, titled “Overspending Driven by Oversized Single Dose Vials of Cancer Drugs” examined expected pharmaceutical company revenue from discarded portions of the top 20 cancer drugs dosed by body size in the US. The study found that the amount of leftover drug from single-use vials varies from 1% to 33% and estimated that in 2016, drug companies in the US will earn $1.8 billion in extra revenue from leftover cancer drugs.

According to researchers, many cancer drugs sold in single-use vials are dosed by the body size or weight of the patient. As a result of this, the researchers suggest, pharmaceutical companies may be able to artificially increase the amount of drug sold per patient. Drug companies may do this by “increasing the amount in each single-dose vial relative to the typically required dose.”

According to the study, when hospitals or doctors are forced to purchase oversized vials that do not easily fit typical dosing requirements for a drug, they may end up discarding the remaining contents in the vial. Safety standards set by the US Pharmacopeial Convention “permit sharing only if leftover drug is used within six hours, and only in specialized pharmacies.” This leaves a limited window for a drug to be used for multiple patients.

In one example, the researchers cite pembrolizumab, which is approved by FDA for the treatment of melanoma and metastatic non-small cell lung cancer and is manufactured by Merck in the US. According to researchers, in 2015, Merck began distributing the drug in 100 mg vials, an increase in the amount from the original 50 mg vials. Increasing the percentage of medicine in the vial upped the amount of discarded medicine. Therefore a hospital administering a 140 mg dose of the drug with a 100 mg vial, would have 60 mg left over, as opposed to 10 mg with the 50 mg vial.

Pamela L. Eisele, a spokeswoman for Merck, told the New York Times that the company hopes FDA will approve a fixed dose of 200 mg for all patients on Keytruda. Eisele said that this “will eliminate wastage.” According to the publication, 200 mg is higher than the dosage given to nearly all patients, and there is no evidence that a higher dosage was more effective.  

The researchers claim the increase in vial sizes can be expensive for patients and insurance companies, which are billed for the entire single-use dose, even if the entire dosage is not used. These bills also include “percentage-based markups,” which, the study says, “can equate to large amounts of money given that many of the drugs cost thousands of dollars per vial.”

The researchers say discarding expensive drugs is “antithetical to efforts to reduce spending on healthcare services that provide no value.” They say FDA has been “inconsistent” in guidances on vial sharing. The Centers for Disease Control has been vocal about single-dose vials, saying they are preferred over multiple-dose vials. The researchers say one solution is instituting regulatory requirements on manufacturers to create drugs in various size options. According to researchers, differentiating sizes of dosages could potentially lower revenue from leftover drugs from the estimated $1.8 billion to $400 million in 2016. 

Source: BMJ