https://grants.nih.gov/grants/guide/rfa-files/RFA-HL-25-011.html
The objective of this limited competition Notice of Funding Opportunity (NOFO) is to solicit current or recently completed NHLBI K01, K08, K23, and K25 recipients for small grant support to expand their current research goals or to branch out to a new study that resulted from the research conducted under the K award. Active NHLBI K01, K08, K23, and K25 recipients may apply for R03 support after the notice of award (NoA) for their first type-5 K awards has been issued. Recently completed NHLBI K01, K08, K23, and K25 recipients are eligible to apply for the R03 if the earliest possible R03 start date falls within 2 years of their prior NHLBI K award Project Period end date. This NOFO is intended to enhance the capability of NHLBI K01, K08, K23, and K25 recipients to conduct research as they complete their transition to fully independent investigator status.
This R03 program is intended to support research projects that can be carried out and completed within a short period of time (no more than two years) with limited resources and that may generate preliminary data to support a subsequent R01-equivalent application. These studies include, but are not limited to, pilot or feasibility studies; proof of concept studies; secondary analysis of existing data; small, self-contained research projects; development of new research methodologies or technologies, or development of novel experimental models. A minimum of 40% protected overall research effort, not necessarily limited to the proposed R03 project, is required from applicants. For current and previous K23 recipients, research proposed in the R03 application may or may not include patient-oriented research.