This bill, titled the Rolling Active Pharmaceutical Ingredient and Drug Reserve Act (RAPID Reserve Act), seeks to significantly improve the supply chain resiliency for critical drug products and their active pharmaceutical ingredients (APIs). It mandates the Secretary of Health and Human Services (HHS) to award contracts or cooperative agreements to eligible entities to maintain a 6-month reserve , or another reasonable quantity, of specified critical APIs and finished drug products. These reserves must be regularly replenished with recently manufactured supplies to ensure their freshness and availability. Contracted entities are also required to implement drug production at the Secretary's direction and agree to transfer API reserves to other manufacturers if needed. The Secretary gains authority to direct the allocation of these API reserves during public health emergencies, natural disasters, or chemical, biological, radiological, or nuclear threats. The bill directs the Secretary to issue guidance on identifying vulnerable supply chains, determining entity eligibility, and outlining program requirements, with a strong preference given to entities that utilize domestic establishments for manufacturing or source key materials domestically or from OECD member countries. An appropriation of $500,000,000 is authorized for fiscal year 2026 to carry out this section.