Prentis R A, Walker S R
Br J Clin Pharmacol. 1986 Apr;21(4):437-43. doi: 10.1111/j.1365-2125.1986.tb05219.x.
One hundred and ninety-seven new chemical entities (NCEs) were investigated in man for the first time between 1964 and 1980 by the seven UK-owned pharmaceutical companies. Thirty-five of these NCEs have been marketed and 137 withdrawn from further research and development. There was an increase in the number of NCEs investigated each year, but this was counter-balanced by an increase in the number rejected. Development times increased from about 4.5 years in the 1960s to 9 years in the 1970s with an accompanying reduction in the effective patent life.
1964年至1980年间,英国的七家制药公司首次在人体中对197种新化学实体(NCEs)进行了研究。其中35种NCEs已上市,137种已停止进一步研发。每年研究的NCEs数量有所增加,但被拒数量的增加抵消了这一增长。研发时间从20世纪60年代的约4.5年增加到70年代的9年,同时有效专利寿命缩短。