The good news from the early days of COVID-19 vaccination—that extra doses might be squeezed out of vials containing Pfizer’s COVID-19 vaccine—shed light on a convention that clinicians know well. Drug vials often contain more than the indicated dose, whether to account for the range of possible dose sizes for patients of various weights, or as a simple contingency against minor spills.

But the practice of overstuffing vials has come under scrutiny, with one 2016 report estimating that the federal government and private insurers waste $2.8 billion each year by throwing away vials that contain leftover cancer medicine.

“I can assure you that payers are charged for the full cost of the vial, and patients may even pay out of pocket for their portion of the costs,” says Edward Shortliffe, professor of biomedical informatics at Columbia University. “Yet a significant portion of the drug ends up discarded.”

Shortliffe recently chaired a special committee from the National Academies of Sciences, Engineering, and Medicine to study the problem. Its report recommends exploring technologies to allow multiple patients to benefit safely from medicine in a single-dose vial, and to revisit potentially outdated guidelines for weight-based dosing. “We should expect drug developers to provide evidence that a drug needs to be weight-based,” Shortliffe says. “If the same dose had the same impact on every patient, we could put the precise dose in each vial and very little would need to be discarded.”

Crucially, however, the report is skeptical that money wasted at the bottoms of single-dose vials can be recovered. Because pharmaceutical companies price drugs based on the perceived value of the drug to the patient and the payer’s willingness to pay, more patients benefiting from the content of a single-dose vial might only lead to the companies raising the price per bottle, the researchers note. Pfizer recently demonstrated this frustrating pricing philosophy with the announcement that it would send fewer vials of COVID-19 vaccine than initially expected, because clinicians managed to squeeze six doses out of five-dose vials.

“Pfizer has made it clear that drug pricing is based on treatment per patient, not the actual production cost of a vial,” Shortliffe says.

While medicine left behind in a vial may seem like liquid gold, “if we want to address the problem, we are going to need to look at the overall efficiency of how drugs are developed, manufactured, distributed and administered,” Shortliffe says.