Preferred choice of GnRH analogue injection for prostate cancer in NCL 

Triptorelin or (Decapeptyl® SR) is the preferred GnRH analogue product in NCL. All new patients will be routinely initiated on this as the first choice product where clinically appropriate. Patients receiving one of the other GnRH analogue injections will be switched to triptorelin where clinically appropriate but some patients may remain on alternative hormone injections. For more information on administering these, please see Resources section.

Why is triptorelin (Decapeptyl® SR) the preferred GnRH analogue?

There are currently three GnRH analogue products available for prostate cancer: leuprorelin, goserelin and triptorelin. There are differences between these products in terms of the injection route and administration intervals. Leuporelin and goserelin are three-monthly preparations administered subcutaneously; goserelin is an implant and requires a specific administration technique due to the larger needle device. Triptorelin is an intramuscular injection and is available in a three-monthly and six-monthly preparation. 

An evidence review and budget impact assessment has been undertaken by the NCL Joint Formulary Committee for these agents. Evidence for the efficacy of these agents in this indication is well documented. Use of the triptorelin six-monthly administration injection would reduce the number of appointments required, resulting in cost-savings in the longer term and facilitate benefits in patient convenience. The intramuscular route may be more comfortable for patients than the subcutaneous implant and easier for the clinician to administer. Please see the NCL Fact Sheet for GnRH analogues in prostate cancer for further information.

This change to the NCL preferred choice of GnRH analogue injection is to offers patients (where clinically appropriate) the option of having a six-monthly injection to reduce the frequency of administration appointments so that they don’t need to visit their GP so often. This has already been implemented in secondary care during the pandemic for suitable patients, to minimise attendance at hospital appointments.