NHLBI Small Business Program (SBIR/STTR)

NHLBI's Small Business Program is the institute's main non-dilutive route for US companies building heart, lung, blood, and sleep disorder technologies. It covers both SBIR and STTR mechanisms, uses the NIH parent solicitations, and adds NHLBI Notices of Special Interest across the institute's priority areas. The program supports early-stage R&D through the R43/R44 and R41/R42 mechanisms. The standard Phase II ceiling is $2.1 million, with US for-profit companies as the required applicant type and both registration and operations based in the United States. Applications run on two NIH cycles each year, typically in April and September, and NHLBI also points companies to I-Corps, CRP, C3i, TABA, NCAI, and REACH hubs. The strongest fit is a small business with a technical product and a clear path through preclinical or product-development milestones. The institute's interest areas span maternal and women's health, AI and machine-learning diagnostics, RNA delivery, biomaterials, digital health, and precision medicine, so teams with a product-focused plan and an evidence-building strategy tend to fit best.

Each grant below is a distinct funding opportunity with its own eligibility, scope, and deliverables.