/ President Biden has said he plans to invoke the Defense Production Act to provide more COVID vaccines, but forcing companies to gear up production won’t provide much-needed doses anytime soon. Americans are dying of COVID-19 by the thousands, but efforts to ramp up production of potentially lifesaving vaccines are hitting a brick wall. Vaccine makers Moderna and Pfizer-BioNTech are running their factories full tilt and are under enormous pressure to expand production or collaborate with other drug companies to set up additional assembly lines. That pressure is only growing as new viral variants of the virus threaten to launch the country into a deadlier phase of the pandemic.