Researchers described an accelerated sterility testing protocol capable of yielding reliable sterility results in one day for biopharmaceuticals. The method combines optimized culture conditions, sensitive detection endpoints, and statistical validation to meet regulatory expectations for sterility assurance. If accepted by regulators, a validated one‑day sterility assay could reduce batch hold times, speed clinical supply release, and lower inventory costs for cell and gene therapies and other steriles. Authors note harmonization with pharmacopeial standards and external proficiency testing will be necessary for industry adoption.