Gonadotropin-releasing hormone analogues (GnRH-analogues) are well established for treating advanced prostate cancer. In 2015 and 2016, four GnRH-analogues were available in Germany: Buserelin, Goserelin, Leuprorelin and Triptorelin. Only Leuprorelin had generics. Four of 17 regions of physicians’ associations (KV) in the statutory health insurance (SHI) had quotas promoting Leuprorelin in 2015 and 2016 (“Quota-KVs”). Four regions introduced quotas in 2017 (“New-KVs”). This research investigates the regional differences in market penetration and potential savings. QuintilesIMS provided monthly SHI prescription data per region, sickness fund and package for 2015 and 2016. Pharmacy sales prices and defined daily doses (DDD) were used for sales respectively volume. Total sales were 207.7m (212.3m) Euro and volume was 37.6m (38.3m) DDD in 2015 (2016). The average quarterly market share (sales) of Leuprorelin differed regionally between 60.5% and 75.7%. Within the Leuprorelin market, the average generics’ share varied between 5.9% and 33.6%. In the “Quota-KVs”, the average share was 23.9% compared to 12.2% in the “New-KVs” and 14.3% in the remaining nine. Leuprorelin generics had a more cost-effective average price level (4.51 Euro/DDD) than other Leuporelin products (5.38 Euro/DDD) and GnRH-analogues (6.02 Euro/DDD). SHI could have saved 20.6m Euro or 4.9% of sales in 2015 and 2016, when the highest quarterly market shares (DDD) of Leuprorelin in a KV (79.7%) and generics within Leuprorelin (45.8%) would have been achieved over all quarters and KVs. Average potential savings per KV varied between 2.0% and 6.9%. Average potential savings would have been 3.5% in “Quota-KVs” and 5.7% in “New-KVs” as well as the remaining nine. The analysis shows a low market share for generics and a strong deviation between regions. Quotas push market penetration for generics. Regions with lower shares have recently introduced them. Substantial savings can be achieved without any loss of clinical effectiveness.