As the Department of Health and Human Services purchases more of Abbott’s rapid antigen tests, competitor Beckman Coulter said it is seeking an emergency use authorization for its $4 antigen test.The Brea, Calif.-based device and diagnostics company said it would begin shipping 18 million tests, which it plans to ramp up to 25 million tests per month by March. Though the FDA has not authorized its test, it is still able to perform testing in high-complexity and point-of-care settings while it is under review.