Researchers invited to submit proposals for new round of ancillary pathobiology studies 

The National Institutes of Health (NIH) invites researchers—both within and outside of RECOVER—to submit proposals for a new round of funded ancillary pathobiology research studies designed to answer critical questions about Long COVID. This new Research Opportunity Announcement (ROA) seeks to fund studies that will expand RECOVER's scientific knowledge about the biological mechanisms of the condition. RECOVER pathobiology studies focus on analyzing small amounts of tissue, blood, and saliva—known as biosamples—to understand what happens inside the body when a person develops Long COVID.

“To date, RECOVER has funded many exciting pathobiology studies, and some of these studies have also revealed additional questions that need to be investigated,” said Christine Bevc, PhD, Pathobiology Study Manager at RECOVER’s Administrative Coordinating Center (ACC). “With this new round of funding, we hope to answer some of these lingering questions [about Long COVID] while also expanding RECOVER’s scientific network. By bringing in researchers who haven’t yet been involved with RECOVER, we can bring in new expertise and ensure that RECOVER’s resources are put to good use.”

New research funding enables unique explorations of Long COVID in the body

The Research Opportunity Announcement (OTA-21-015K) was released on August 1, 2025, and is now open. Proposals will be accepted on a rolling basis through the RECOVER REDCap system. NIH will make funding decisions quarterly, and approved projects will receive funding within 6 months of submission.  

This new ROA will fund projects that make the most of RECOVER’s established resources, including its vast biosample repository, clinical data from study visits, specialized imaging (e.g., brain MRI and PET), and ongoing observational studies which include groups of adults, children, and people who died after having Long COVID. Projects that apply cutting-edge tools like artificial intelligence and machine learning are encouraged. As with previous awards, all funded projects will complement, not duplicate, ongoing RECOVER research. 

Some of the new projects that will be funded this round will be short, 1-year studies that use the samples and data RECOVER has already collected. However, new to this round of ROAs is the opportunity for studies that extend for multiple years. These will be ancillary studies, or studies that answer questions beyond RECOVER’s original protocol. They will focus on answering research questions that address critical and emerging research gaps, such as how Long COVID affects the heart and lungs, brain, and nervous system; and reactions in the immune system.

These studies will also provide the opportunity to prospectively examine, or examine over time, new biosamples as participants enroll in RECOVER’s continuing studies and contribute samples in the future. Prospective research can help researchers better understand the trajectory of Long COVID and how it changes the body over a longer period of time. This is a departure from previous pathobiology studies that emphasized retrospective research, meaning that they examined biosamples that were contributed in the past and already part of RECOVER’s biorepository.

Researchers from previously funded RECOVER pathobiology studies and new researchers not affiliated with RECOVER are encouraged to apply to this round of awards. This is an expansion from the previous rounds of ROAs, where applications were limited to study teams working at or partnering with RECOVER study sites. Proposals will be evaluated based on how well they are likely to use RECOVER’s existing resources to accelerate discoveries about the biological mechanisms behind Long COVID. This knowledge can supplement findings from RECOVER’s previously funded studies, such as its systems biology and pathology studies, to provide a more complete picture of Long COVID and how its biological mechanisms impact symptoms.

RECOVER builds a robust pathobiology portfolio to study biological mechanisms of Long COVID 

RECOVER has funded over 60 pathobiology studies to investigate biological mechanisms of how SARS-CoV-2, the virus that causes COVID-19 and Long COVID, impacts the body. The first pathobiology investigations were awarded through a Notice of Special Interest (NOSI) in 2021, inviting researchers who were working on NIH-funded studies to apply for additional funding to add a Long COVID focus to their existing work. Many of these early funded studies looked at how Long COVID affects people with other chronic health conditions, such as HIV and mononucleosis. Some of the studies used model organisms—like mice, fruit flies, bacteria, and yeast—to help explore the relationship between Long COVID and other diseases and conditions. 

In 2022, NIH expanded these investigations by giving RECOVER researchers opportunities to conduct new pathobiology studies. The studies funded through this ROA (PDF, 695 KB) focus on how the biological mechanisms causing the different types of Long COVID can lead to a wide range of symptoms and effects on body systems.

An additional ROA in 2024 called for studies using existing RECOVER data and biosamples contributed by RECOVER study participants. This round of research also prioritized research areas different from the first ROA, such as viral persistence (when parts of the SARS-CoV-2 virus stay in the body for a long time), SARS-CoV-2 reinfection and variants, and the association of social factors and preexisting conditions with Long COVID risk and severity.

Hannah Wright, MS, another Pathobiology Study Manager at RECOVER’s ACC, shared how findings from all of these studies continue to broaden our understanding of Long COVID. “The volume of findings, connections, and evidence continues to grow,” she said. “We’re seeing the expansion of this scientific community beginning to exchange knowledge and make those critical connections.”

Current RECOVER pathobiology study areas include but are not limited to: 

• Viral persistence: This area explores how parts of the SARS-CoV-2 virus might stay in the body after infection and contribute to Long COVID. Studies may look at how reinfections, repeated exposures, or vaccines affect someone’s risk for Long COVID. Researchers study why some people with lingering virus particles develop Long COVID, while others don’t.
• Validating past research using RECOVER data: Researchers revisit findings about Long COVID from earlier studies and test them using RECOVER’s data and biosamples. This helps confirm that results are valid and reproducible.
• Comparative studies with other post-infection conditions: This area compares Long COVID to other post-infection illnesses to identify shared or unique causes. Researchers also work to understand how Long COVID may affect children differently than adults.
• Long COVID in special populations: This area explores how Long COVID affects different groups such as people who are pregnant, have chronic conditions (e.g. Alzheimer’s), and live with social or economic disadvantages. Understanding these patterns can support better outcomes among people from all walks of life and improve care for people who are most at risk.
• Therapeutic targets and drug development: Findings from studies can help identify new treatments or suggest ways to reuse existing drugs. This includes using samples from RECOVER clinical trials to test how well treatments work and developing lab tests to support future research.

Explore current pathobiology studies, or learn more about how to submit your proposal for new funding.