For sickle cell anemia with recurrent moderate to severe painful crises. NDA 208843, held by Theravia. Hydroxyurea.
As of Nov 15, 2026, NDA 208843 (Siklos), held by Theravia, was first approved by FDA on Dec 21, 2017, with 4 approved supplements and 0 published complete response letters.
SIKLOS is indicated to reduce the frequency of painful crises and to reduce the need for blood transfusions in adult and pediatric patients, 2 years of age and older, with sickle cell anemia with recurrent moderate to severe painful crises
| Jan 22, 2025 | Supplement 5Efficacy (new indication or use) · Standard review | Tentative approval | |
| Dec 7, 2021 | Supplement 3Efficacy (new indication or use) · Standard review | Approved | |
| Dec 21, 2017 | Original applicationNew dosage form · Standard review | Approved |
| Siklos100MG · tablet;oral | Hydroxyurea | RxReference drug |
| Siklos1GM · tablet;oral | Hydroxyurea | RxReference drug |
| Jan 22, 2025 | Supplement 5Efficacy (new indication or use) · Standard review | Tentative approval | |
| Nov 28, 2023 | Supplement 4Labeling · Standard review | Approved | |
| Dec 7, 2021 | Supplement 3Efficacy (new indication or use) · Standard review | Approved | |
| May 22, 2019 | Supplement 2Labeling · Standard review | Approved | |
| Dec 12, 2018 | Supplement 1Labeling · Standard review | Approved | |
| Dec 21, 2017 | Original applicationNew dosage form · Standard review | Approved |
Approvals, supplements, products and documents come from FDA's Drugs@FDA data files, refreshed daily; Drugs@FDA lists approved applications only. Complete response letters are FDA's published letters. Drugs@FDA and FDA complete response letters
