Desogestrel
| Evidence Level: L4 | Predicted Indications: 10 |
Table of Contents
Desogestrel: From Oral Contraception to Amenorrhea
One-Sentence Summary
Desogestrel is a progestin used in oral contraceptive tablets, alone or combined with ethinylestradiol. The TxGNN model predicts it may be useful for amenorrhea. Support is thin: 2 clinical trials and 16 publications were retrieved, but none show desogestrel treating amenorrhea directly.
Quick Overview
| Item | Content |
|---|---|
| Original Indication | Oral contraception (inferred from the product class; the registration data contain no approved indication text) |
| Predicted New Indication | Amenorrhea |
| TxGNN Prediction Score | 99.96% |
| Evidence Level | L4 |
| South Africa Market Status | Marketed |
| Number of SAHPRA Registrations | 2 |
| Recommended Decision | Hold |
Why is This Prediction Reasonable?
Currently, detailed mechanism of action data is not available. Based on known information, desogestrel is a progestin that suppresses gonadotropins. Combined with ethinylestradiol, it provides cyclic hormonal support, so it may be applicable to functional or hypothalamic amenorrhea.
The link is plausible but unproven. The high TxGNN score is not backed by desogestrel-specific efficacy data. Combined pills mainly regulate withdrawal bleeding and do not restore ovulatory function. Amenorrhea also appears in the literature mostly as a bleeding pattern of progestin-only pills, not as a condition they treat.
Clinical Trial Evidence
| Trial Number | Phase | Status | Enrollment | Key Findings |
|---|---|---|---|---|
| NCT00946192 | Phase 3 | Completed | 121 | Reproductive and endocrine function in young athletes, including oral or transdermal estrogen for bone health in athletes with amenorrhea. Desogestrel as an intervention arm is not evident, and amenorrhea is not clearly the primary endpoint. |
| NCT01588873 | Phase 4 | Unknown | 42 | Contraceptive pill versus vaginal ring on hormonal and metabolic markers in PCOS. Does not address amenorrhea treatment. |
Literature Evidence
| PMID | Year | Type | Journal | Key Findings |
|---|---|---|---|---|
| 11725730 | 2001 | Not classified | J Reprod Med | Effect of decreasing ethinylestradiol doses in oral contraceptives on bone loss in young women with hypothalamic amenorrhea. |
| 23221134 | 2012 | Not classified | Georgian Med News | Management of central-origin oligomenorrhoea and amenorrhoea in 159 infertile women, compared with standard hormone therapy. |
| 35261299 | 2022 | Not classified | Gynecol Endocrinol | Bleeding profile of a drospirenone-only pill versus desogestrel 75 mcg. Amenorrhea appears as a bleeding pattern of progestin-only pills. |
| 3161265 | 1985 | Pharmacodynamic study | Acta Obstet Gynecol Scand Suppl | Androgenicity of progestogens, with a focus on desogestrel, alone and with ethinylestradiol. |
| 8218004 | 1993 | Comparative clinical study | Br J Obstet Gynaecol | Reliability, cycle control and side effects of two 150 µg desogestrel pills with 20 µg (Mercilon) or 30 µg ethinylestradiol. |
| 18843653 | 2008 | Systematic review (Cochrane) | Cochrane Database Syst Rev | 20 µg versus higher-dose estrogen combined pills: contraceptive effectiveness and bleeding patterns. |
| 21249657 | 2011 | Systematic review (Cochrane) | Cochrane Database Syst Rev | Updated version of the same review. |
| 8447356 | 1993 | Not classified | Am J Obstet Gynecol | Tolerability profile of desogestrel/ethinyl estradiol and the non-contraceptive benefits of oral contraceptives. |
| 1436906 | 1992 | Not classified | Obstet Gynecol Surv | Overview of the newer progestogens desogestrel, norgestimate and gestodene. |
| 1604074 | 1992 | Review | Rev Med Liege | General review of hormonal contraception. |
South Africa Market Information
| Registration Number | Product Name | Dosage Form | Approved Indication |
|---|---|---|---|
| 49/18.8/0711 | Merdeza | Tablet (oral) | Not stated in registration data |
| Y/18.8/78 | Mercilon | Tablet (oral) | Not stated in registration data |
Safety Considerations
Please refer to the SAHPRA-approved Professional Information (PI) for safety information. Report adverse drug reactions to SAHPRA.
Conclusion and Next Steps
Decision: Hold
Rationale: No trial or publication shows desogestrel treating amenorrhea. The only Phase 3 trial is in young athletes and does not clearly involve desogestrel. The high TxGNN score therefore rests on the model prediction alone (L4).
To proceed, the following is needed:
- The SAHPRA Professional Information (warnings, contraindications, approved indications), which is a blocking gap for safety screening
- Detailed mechanism of action data (for example from DrugBank)
- A desogestrel-specific efficacy study in functional or hypothalamic amenorrhea, with amenorrhea as the endpoint
- A comparison against standard hormone therapy
For context, the same evidence pack ranks acne (rank 4) higher on evidence (L2, Proceed with Guardrails). It is supported by a completed Phase 4 trial and desogestrel-specific studies, but the effect comes from the estrogen-progestin combination. Venous thromboembolism risk with third-generation progestins (PMID 10652979) would need to be part of patient selection.
This report is for research reference only and does not constitute medical advice. Predicted indications require clinical validation before any use.
Disclaimer
This content is for research purposes only and does not constitute medical advice. Clinical validation is required before any clinical application.