Norethindrone acetate
As of the edition of 20 October 2026, Norethindrone acetate is a small molecule: marketed, first approved in 1961 (CA); acts on PGR.
Sources: FDA Orange Book and Purple Book, other approval registers, ClinicalTrials.gov, ChEMBL.
The drug
- Status
- Marketed; latest approval 2021
- Kind
- Small molecule
- Brand name
- Loestrin 21 1/20
- First approved
- 31 December 1961 (CA)
- Approvals on record
- 37 in 5 regions
- Holder of the most recent approval
- Millicent Manufacturing Pr; 16 holders in all
- Registered trials
- 47, 6 stopped early
- Disease areas
- Urinary and reproductive; Pregnancy and women's health; Cancer; Skin and connective tissue; Immune system; Blood and lymph
US protection
No US approval on record.
With no US approval on record there are no listed US patents or exclusivities.
This is the US only.
Companies that need a new molecule because of this drug
3 companies on route B because of this drug.
Companies on route B for this drug
In the product3 companies are on route B because of Norethindrone acetate.
See the 3 companies on route B for this drug, with the facts behind eachRequest access. Nothing is shown until you do.
Target
| Gene | Protein | UniProt |
|---|---|---|
| PGR | Progesterone receptor | P06401 |
Registered trials
| Phase | Trials | Completed | Active | Stopped early |
|---|---|---|---|---|
| Phase not stated | 10 | 3 | 4 | 1 |
| Phase 1 | 9 | 8 | 1 | 0 |
| Phase 2 | 4 | 2 | 0 | 2 |
| Phase 3 | 21 | 18 | 0 | 2 |
| Phase 4 | 3 | 1 | 0 | 1 |
| All trials | 47 |
Who has held its approvals
| Company | Role | Years |
|---|---|---|
| Novo Nordisk | Applicant and Lead sponsor of trials | 1977 to now |
| Pfizer | Applicant and Later holder | 1982 to now |
| ASKA Pharmaceutical | Applicant | 2008 to now |
| Duramed | Acquired holder | 2009 to now |
| AbbVie | Applicant and Lead sponsor of trials | 2013 to now |
| Gedeon Richter | Applicant | 2021 to now |