---
kind: "section"
citation: "21 C.F.R. § 314.100"
title: "21"
number: "314.100"
heading: "Timeframes for reviewing applications and abbreviated applications."
url: "https://uscodex.org/cfr/21/314.100"
---

# §314.100. Timeframes for reviewing applications and abbreviated applications.

- (a) Except as provided in [paragraph (c)](#c) of this section, within 180 days of receipt of an application for a new drug under [section 505(b)](/cfr/21/505.md?p=b) of the act or an abbreviated application for a new drug under [section 505(j)](/cfr/21/505.md?p=j) of the act, FDA will review it and send the applicant either an approval letter under [§ 314.105](/cfr/21/314.105.md) or a complete response letter under [§ 314.110](/cfr/21/314.110.md). This 180-day period is called the “initial review cycle.”
- (b) At any time before approval, an applicant may withdraw an application under [§ 314.65](/cfr/21/314.65.md) or an abbreviated application under [§ 314.99](/cfr/21/314.99.md) and later submit it again for consideration.
- (c) The initial review cycle may be adjusted by mutual agreement between FDA and an applicant or as provided in §§ [314.60](/cfr/21/314.60.md) and [314.96](/cfr/21/314.96.md), as the result of a major amendment.

## Notes

### Amendments

[73 FR 39609, July 10, 2008]

### Source

Source: 50 FR 7493, Feb. 22, 1985, unless otherwise noted. Redesignated at 57 FR 17983, Apr. 28, 1992.

### Authority

Authority: 21 U.S.C. 321, 331, 351, 352, 353, 355, 355a, 355f, 356, 356a, 356b, 356c, 356e, 360cc, 360ddd, 360ddd-1, 371, 374, 379e, 379k-1.

### Source

Source: 50 FR 7493, Feb. 22, 1985, unless otherwise noted.

### Amendments

[73 FR 39609, July 10, 2008]