The NIH A1 resubmission — one shot, on a 37-month clock.
After a scored review you get a single opportunity to resubmit as an A1. The A2 was retired in 2009. The rules that follow are the ones reviewers, SROs, and eRA Commons actually enforce — not folklore.
- One A1 per A0. No A2.
- A1 must be submitted within 37 months of the original A0.
- A1 requires a 1-page Introduction responding to the prior critique.
- You can't submit the A1 before the A0 summary statement is issued.
- After an unsuccessful A1, the same idea may come back as a fresh A0 — with no Introduction.
One resubmission per original application
NIH accepts a single amended application (A1) of any given A0. The A2 was eliminated in 2009. An A1 that isn't funded cannot be resubmitted as an A2; the next attempt must be a brand-new A0.
The 37-month clock
An A1 must be submitted within 37 months of the original A0 submission date. After 37 months NIH will treat any submission on the same idea as a new A0 regardless of whether an A1 was ever filed — you lose the option, not just the right to call it A1.
The 1-page Introduction is mandatory
Every A1 includes an Introduction (typically 1 page for R-series; 3 pages for multi-project) that responds to the prior summary statement. It must address each substantive critique from the assigned reviewers and summarize the changes made in the Research Strategy. Changes in the Research Strategy itself should be marked (vertical bar in the margin, italics, or the convention specified by the NOFO).
Our Mock Study Section auto-generates a first-draft NIH-format Introduction (.docx) from your scored critique. How the Mock Study Section works →
You can't overlap the A0 and the A1
The A1 cannot be submitted before the summary statement from the A0 has been released. NIH also does not allow two overlapping applications on essentially the same science under review simultaneously — if the A0 is still under review, the A1 will be withdrawn.
After an unsuccessful A1: submit a new A0
If the A1 isn't funded, you may submit the same idea as a brand-new A0 for the next appropriate due date. The new A0 must not contain an Introduction responding to prior critiques and is reviewed as a never-before-seen application. Practically, most successful teams take the critique into the new A0 anyway — they just don't reference the prior review inside the application itself.
Resubmission due dates shift about a month
Standard non-AIDS new-application dates are Feb 5, Jun 5, Oct 5. The corresponding resubmission dates are Mar 5, Jul 5, Nov 5. An A1 submitted in its original cycle still competes on that cycle's council round — the later date just gives you additional preparation time.
Nobody outside the review room can tell you an A1 will fund. What the summary statement is telling you, though, is usually clear enough to decide.
- Score is close to the payline or "high impact" band.
- Critiques are specific and fixable (preliminary data, controls, alternate approaches).
- Factor 1 (Importance) reads well; Factor 2 (Rigor) is what got dinged.
- The study section understood the idea and disagreed on execution.
- Not Discussed, with critiques questioning the premise itself.
- Reviewers didn't see the significance — this is a framing problem, not a data problem.
- The mechanism was wrong for the maturity of the work (e.g. R01 too early — consider R21 or SBIR).
- Study section assignment was a bad fit and can be requested differently.
We don't quote a "resubmission funds X% more" statistic here — the honest answer depends heavily on IC, mechanism, and cycle, and any single number would mislead you. Read the summary statement, talk to your PO, then decide.
Establishes that NIH accepts a single amended (A1) version of any A0. Prohibits overlapping A0/A1 submissions under review at the same time.
The A1 must be submitted within 37 months of the original A0. After that window, any submission on the same idea is treated as a new application regardless of prior A1 use.
Governing policy for what the A1 Introduction must contain and the rule that a fresh A0 following an unsuccessful A1 must not include an Introduction responding to prior critiques.
CSR's applicant-facing guidance on how resubmissions are assigned, reviewer continuity, and the practical mechanics of the A1 process.
Standard non-AIDS resubmission dates (Mar 5, Jul 5, Nov 5) run one month behind the corresponding new-application dates (Feb 5, Jun 5, Oct 5).