Regional differences in potential savings for the medical treatment of advanced prostate cancer in the German health care system

Title Gonadotropin-releasing hormone analogues (GnRH-analogues) are well established for treating advanced prostate cancer. Four GnRH-analogues were available in Germany for the whole period of 2015 and 2016: buserelin, goserelin, leuprorelin and triptorelin. Only for leuprorelin a generic version existed in the market. This research investigated the regional differences in market penetration and associated potential savings in the GnRH-market. Method IQVIA provided monthly out-patient prescription data per region of physicians' associations (KV) and sickness fund for 2015 and 2016 for the German SHI system. Pharmacy sales prices and defined daily doses (DDD) were used for sales respectively volume calculations. Based on two benchmarks-regional potential savings were calculated. The first benchmark equalled the highest observed quarterly market share (DDD) of the most economical GnRH-analogue in one KV region; the second equalled the highest observed quarterly market share of generics within the most economical GnRH-analogue in one KV region. Results Total sales for GnRH-analogues were relatively stable with 207.7 m and 212.3 m euro in 2015 and 2016. Leuprorelin showed the highest sales market share in Q4 2016 with 69.9 %. Within the leuprorelin market, the originator exhibited the highest sales market share with 59.6 %, whereas the market share of the only generic manufacturer was 18.1 % (Q4 2016). Generic leuprorelin displayed a more cost-effective average price level (4.51 Euro/DDD) than non-generic leuprorelin (5.55 Euro/DDD) and other GnRH-analogues (6.02 Euro/DDD). The average quarterly market share (DDD) of leuprorelin differed regionally between 63.0 % and 79.7 % (Q4 2016). Within the leuprorelin market, the average generics' share varied between 7.8 % and 39.5 %. Regions with "lead compound" quotas showed higher market shares. Four of 17 KV regions had implemented quotas promoting leuprorelin in 2015 and 2016. Five regions introduced new quotas in 2017. The SHI system could have saved 20.6 m euro in this two years if all KV regions had achieved the two benchmarks. Conclusions Low market shares of generics and strong regional differences characterize the GnRH-market for prostate cancer. Typical instruments to promote the prescription of generic drugs do not apply in this case. However, " lead compound" quotas can be an effective tool to push market penetration for generic drugs. Substantial savings can be expected through quotas without any loss in health care quality.