Are Goserelin and Triptorelin in the same group of medicine?

Goserelin and Triptorelin: Classification and Clinical Applications

Yes, goserelin and triptorelin belong to the same group of medicines - they are both gonadotropin-releasing hormone (GnRH) agonists. 1, 2

Mechanism of Action

Both medications work through the same mechanism:

• Initially stimulate gonadotropin release (LH and FSH)
• With continuous administration, cause downregulation of GnRH receptors
• Lead to suppression of sex hormone production (testosterone in men, estradiol in women)
• Result in medical castration when used long-term 3, 1

Clinical Applications

Breast Cancer

• Both agents can be used for ovarian suppression in premenopausal women with hormone receptor-positive breast cancer
• Goserelin is administered at 3.6 mg SC every 4 weeks or 10.8 mg SC every 12 weeks 4
• Used in combination with tamoxifen or aromatase inhibitors for adjuvant therapy 4, 5
• Shown to improve disease-free survival when combined with tamoxifen versus tamoxifen alone (85.4% vs 80.2% at 8 years) 4

Prostate Cancer

• Both are effective for androgen deprivation therapy in advanced prostate cancer
• Comparable ability to suppress testosterone to castration levels (≤50 ng/dL in a month and ≤20 ng/dL in 3 months) 1
• Some studies suggest goserelin may have better efficacy in maintaining testosterone levels ≤50 ng/dL compared to leuprolide, but direct comparative data with triptorelin is limited 6

Administration and Formulations

• Goserelin: Subcutaneous biodegradable depot releasing approximately 120 μg/day over 4 weeks 3
• Triptorelin: Intramuscular depot formulation
• Both are available in monthly and 3-monthly formulations 1

Efficacy Considerations

While both agents belong to the same class and have similar mechanisms of action, some differences have been noted:

• Limited direct comparative studies exist between these specific agents 6
• Some studies suggest potential differences in testosterone control, but definitive conclusions cannot be drawn from existing evidence 6
• The clinical significance of any minor pharmacological differences remains uncertain 2

Side Effects

Both medications share similar side effect profiles:

• Initial disease "flare" due to temporary hormone surge
• Hot flashes
• Sexual dysfunction
• Decreased bone mineral density with long-term use
• Fatigue 1

Clinical Implications

When selecting between these agents, consider:

1. Available formulations and dosing schedules
2. Patient preference regarding administration route
3. Local availability and cost
4. Specific indication (breast cancer, prostate cancer, or other conditions)

Both medications are effective GnRH agonists with established efficacy in their approved indications, and the choice between them often depends on practical considerations rather than significant differences in clinical outcomes.