Economic impact of tibolone compared with continuous-combined hormone replacement therapy - In the management of postmenopausal women with climacteric symptoms in the UK

Objective: To estimate the economic impact of using tibolone 2.5 mg compare d with 17 beta -estradiol 2 mg/norethisterone acetate 1 mg (E-2/NETA) ill p ostmenopausal women with climacteric symptoms. Design and setting: This was a modelling study performed from the perspecti ve of the UK's National Health Service (NHS). Methods: The clinical outcomes from a previously reported trial were used a s the clinical basis for the analysis, which showed that 48 weeks' treatmen t with tibolone and E-2/NETA significantly alleviated the climacteric sympt oms experienced by postmenopausal women. These data were combined with reso urce utilisation estimates derived from a panel of 10 GPs and 3 gynaecologi sts, enabling us to construct a Markov model depicting changes in the healt h status of postmenopausal women. The model was used to estimate the expect ed NHS costs and consequences after 48 weeks' treatment with tibolone and E -2/NETA. Main outcome measures and results: The mean expected direct healthcare cost of using tibolone and E-2/NETA to manage postmenopausal women fur 48 weeks was estimated to be pound 260 and pound 239 (1997/1998 prices) per patient , respectively. Starring hormone replacement therapy (HRT) with tibolone in stead of E2/NETA was equally effective in alleviating climacteric symptoms (65.9 and 62.2%, respectively; p = 0.516) over 38 weeks acid significantly reduced the incidence of vaginal bleeding by 36% (p < 0.0001) acid breast t enderness by 57% (p < 0.0001) for a mean additional cost of pound 21 (rangi ng between -pound3 and pound 42) per patient. The acquisition cost of HRT w as the primary cost driver for tibolone-treated patients, whereas the cost of managing adverse events was the primary cost driver for E-2/NETA-treated patients. Conclusions: The true cost of prescribing tibolone and E-2/NETA is impacted on by a broad range of resources, not only drug acquisition costs. Althoug h the acquisition cost of tibolone is higher than that of E-2/NETA, the dif ference in the expected NHS cost of the first year of treatment between the 2 HRTs is negligible. This is because of the higher incidence of adverse e vents among E-2/NETA-treated patients, which also results in a higher conti nuation rate among tibolone-treated patients. Factors such as patient prefe rences should also be taken into consideration so that treatment choices ar e not decided solely on the basis of acquisition costs.