About Trelstar

What Is Trelstar?

Trelstar is a gonadotropin releasing hormone (GnRH) agonist that is indicated in the palliative treatment of advanced prostate cancer.1 Trelstar reduces serum testosterone concentrations to below castrate level within 1 month of therapy and maintains serum testosterone concentrations below castrate level during continued therapy.1

Trelstar is available in three formulations for administration by intramuscular injection:1

Trelstar is a white to slightly yellow lyophilized cake. When reconstituted, Trelstar has a milky appearance.1 It contains a pamoate salt of triptorelin, a synthetic decapeptide agonist analog of GnRH.1 The Trelstar products are sterile, lyophilized biodegradable microgranule formulations.1 The composition of each Trelstar product is given in the following table:1

Ingredients Trelstar
3.75 mg
Trelstar
11.25 mg
Trelstar
22.5 mg
triptorelin pamoate (base units) 3.75 mg 11.25 mg 22.5 mg
poly-d,l-lactide-co-glycolide 136 mg 118 mg 182 mg
mannitol, USP 69 mg 76 mg 68 mg
carboxymethylcellulose sodium, USP 24 mg 27 mg 24 mg
polysorbate 80, NF 1.6 mg 1.8 mg 1.6 mg

When 2 mL sterile water is added to the vial containing Trelstar and mixed, a suspension is formed which is intended as an intramuscular injection.1 Trelstar is available as a vial plus a MIXJECT® vial adapter, and a separate prefilled syringe that contains sterile water for injection, USP, 2 mL, pH 6 to 8.5.1 Trelstar is also available in a vial alone.