Jan 28, 2021 10:36am Pfizer and BioNTech's COVID-19 vaccine vials contain an extra doses of the in-demand shot, but those doses can only be accessed with a special needle.(Kunal Mahto/iStock/Getty Images Plus/Getty Images) Syringe makers are scrambling to meet demand for so-called low dead space syringes as Pfizer and the U.S. look to squeeze out extra vaccine doses. The specialty needles are needed to eke out a sixth shot in Pfizer and BioNTech's Comirnaty prepared five-dose glass vials. Physicians and pharmacists discovered the potential extra dose after they began vaccinating patients. But initial enthusiasm has been dampened by the requirement of the now-scarce specialty needles to extract the last bit from each vial.