The Small Business Innovation Research (SBIR) and Small Business Technology Transfer (STTR) programs, also known as America's Seed Fund, are one of the largest sources of early-stage capital for technology commercialization in the United States. These programs enable US-owned and operated small businesses to conduct research and development that has a strong potential for commercialization. National Institutes of Health (NIH), Centers for Disease Control and Prevention (CDC), and the Food and Drug Administration (FDA) support small businesses through the SBIR and STTR programs to develop promising technologies and products that align with their mission to improve health and save lives. The SBIR program, as established by law and reauthorized under Public Law 114-328, Section 1834 and Public Law 115-232, is intended to meet the following goals: stimulate technological innovation in the private sector; strengthen the role of small business in meeting federal research and development needs; increase the private sector commercialization of innovations developed through federal research and development funding; and foster and encourage participation in innovation and entrepreneurship by women and socially or economically disadvantaged persons. The STTR program aims to foster technology transfer through cooperative research and development between small businesses and research institutions. Federal agencies with extramural research budgets over $100 million are required to set-aside 3.2% of their extramural research budget to the SBIR program, and those with extramural research budgets over $1 billion are required to set aside an additional 0.45% to the STTR program. SBIR/STTR are phased programs. The main objective in SBIR/STTR Phase I is to establish the technical merit and feasibility of the proposed research and development efforts, whereas in SBIR/STTR Phase II it is to continue the R&D efforts to advance the technology toward ultimate commercialization. An objective of the SBIR and STTR programs is to increase private sector commercialization of innovations derived from federally supported research and development. At the conclusion of an SBIR/STTR Phase II, it is expected that the small business will fully commercialize their product or technology using non-SBIR/STTR funds (either federal or non-federal). Fostering diversity by encouraging the participation of individuals from nationally underrepresented groups in the scientific research workforce is longstanding interest of Congress, and a key component of the NIH strategy to identify, develop, support, and maintain the quality of our scientific human capital (e.g., Public Law 114-329, American Innovation and Competitiveness Act of 2017, and Notice of NIH's Interest in Diversity, NOT-OD-20-031). Scientists and trainees from underrepresented backgrounds and life experiences bring different perspectives, creativity, and individual enterprise to address complex scientific problems. Increasing participation by socially and economically disadvantaged and women-owned small businesses is also critical to the success of the SBIR and STTR programs. Purpose This Funding Opportunity Announcement (FOA) issued by the National Institutes of Health (NIH) invites eligible United States small business concerns (SBCs) to submit Small Business Technology Transfer (STTR) Phase I, Phase II, Fast-Track, and Phase IIB grant applications. Small business applicants interested in submitting an SBIR grant application should submit to PA-21-259 and PA-21-260. NIH Fast-Track: An NIH STTR Fast-Track incorporates a submission and review process in which both Phase I and Phase II applications are submitted and reviewed together as one application to reduce or eliminate the funding gap between phases. NIH Phase IIB: Some projects initiated with SBIR or STTR funding require considerable financing beyond the SBIR and STTR Phase II to achieve commercialization. NIH Institutes and Centers (ICs) may allow small businesses who have been awarded a Phase II SBIR or STTR to submit a Phase IIB (second, sequential Phase II) SBIR or STTR application that will provide additional funding for Phase II SBIR or STTR projects. These renewals are typically offered for those projects that require extraordinary time and effort, including those requiring regulatory approval or developing complex instrumentation, clinical research tools, and behavioral interventions. Commercial potential (i.e. the probability that an application will result in a commercial product) will be strongly considered in review (refer to Section V. Application Review Information) and making funding decisions. An applicant's ability to secure substantial independent third-party investor funds will help validate the commercial potential of the proposed Phase IIB project. Applicants are encouraged to secure substantial independent third-part investor funds (i.e., third-party funds that equal or exceed the requested NIH funds). Examples of third-party investors include, but are not limited to, another company, a venture capital firm, an angel investor, a foundation, a university, a research institution, a State or local government, or any combination of the above. Applicants must provide a commercialization plan that describes the long-term commercialization strategy and details of any independent third-party investor funding that has already been secured or will be provided during the Phase IIB project period. If applicable, the application should include letters of support from third-party investors. NIH ICs that accept Phase IIB applications, either through this SBIR FOA or other specific FOAs, are listed in the PHS 2021-2 SBIR/STTR Program Descriptions and Research Topics for NIH, CDC, and FDA. Additional requirements and instructions (e.g., submission of a letter of intent) are available in the specific IC research topics section and in the NIH Targeted Funding Opportunities that allow Phase IIB applications. Specific Objectives The PHS 2021-2 SBIR/STTR Program Descriptions and Research Topics for NIH, CDC, and FDArepresent scientific program areas that may be of interest to applicant small businesses in the development of projects that have potential for commercialization. Small business concerns that have the research capabilities and technological expertise to contribute to the R&D mission(s) of the NIH awarding components identified in this FOA are encouraged to submit STTR grant applications in these areas. STTR grant applications will also be accepted and considered in any area within the mission of the Components of Participating Organizations listed for this FOA. In addition to the general STTR solicitations, some awarding components have additional, specific NIH Targeted Funding Opportunities of potential interest to small businesses. Applicants are not required to identify a potential awarding component prior to submission of the application but may request one on the Assignment Request Form. Staff within the NIH’s Center for Scientific Review (CSR) office, the single receiving point for all NIH grant applications, will assign all applications to the most appropriate Agency and Institute/Center (IC) based on their mission and the science proposed. For specific information about the mission of each NIH IC, visit the List of NIH Institutes, Centers, and Offices website. All applications submitted to this Parent Funding Opportunity Announcement must propose clinical trial(s). STTR applications that do not propose clinical trial(s) should be submitted to PA-21-262. Applicants should note that some ICs only accept applications proposing mechanistic studies through this funding opportunity announcement and are noted in the PHS 2021-2 SBIR/STTR Program Descriptions and Research Topics for NIH, CDC, and FDA. A mechanistic study is designed to understand a biological or behavioral process, the pathophysiology of a disease, or the mechanism of action of an intervention. If the proposed research project includes clinical trial other than a mechanistic study that would be assigned to one of these ICs, applicants are advised to contact relevant Scientific/Research staff to discuss alternative mechanisms of support of these studies. Further information about the SBIR and STTR programs can be found at https://sbir.nih.gov/. Frequently asked questions are available to assist applicants and can answer many basic questions about the program.