Tibolone increases bone mineral density but also relapse in breast cancer survivors: LIBERATE trial bone substudy.

INTRODUCTION: The Livial Intervention Following Breast Cancer: Efficacy, Recurrence and Tolerability Endpoints (LIBERATE: Clinical http://Trials.gov number NCT00408863), a randomized, placebo-controlled, double-blind trial that demonstrated that tibolone (Livial), a tissue-selective hormone-replacement therapy (HRT), increased breast cancer (BC) recurrence HR 1.40 (95% CI, 1.14 to 1.70; P = 0.001). A subgroup of women was entered into a study of bone mineral density (BMD). METHODS: Women with surgically excised primary BC (T1-3, N0-2, M-0) within the last 5 years, complaining of vasomotor symptoms, were assigned to tibolone, 2.5 mg daily, or placebo treatment for a maximum of 5 years. The BMD substudy enrolled 763 patients, using dual-energy X-ray absorptiometry (DXA) scanning at baseline and at 2 years. RESULTS: In the bone substudy, 699 of 763 women were eligible (345 allocated to tibolone, and 354, to placebo). After undergoing DXA scans, 300 (43%) women had normal BMD; 317 (45%), osteopenia; and 82 (11.7%), osteoporosis. Low body-mass index (P < 0.001), Asian race (P < 0.001), and late age at menarche (P < 0.04) predicted low bone mass at baseline. Tibolone increased BMD by 3.2% at the lumbar spine and 2.9% at the hip compared with placebo (both P < 0.001). The majority of fractures (55%) occurred in osteopenic patients. Women with normal BMD had increased recurrence with tibolone, 22 (15.6%) of 141 compared with placebo, 11 (6.9%) of 159 (P = 0.016), whereas no increased BC recurrence was seen in women with low BMD; 15 (7.4%) of 204 taking tibolone versus 13 (6.7%) of 195 taking placebo. CONCLUSIONS: Tibolone is contraindicated after BC treatment, as it increases BMD and BC recurrence. Risk of BC recurrence was elevated in BC women with normal BMD (compared with low) who took tibolone.

Effects of tibolone on climacteric symptoms and quality of life in breast cancer patients--data from LIBERATE trial.

BACKGROUND: Climacteric symptoms such as hot flushes and vaginal dryness are very common in breast cancer patients, resulting either from age or adjuvant therapy. Tibolone, a synthetic steroid, is effective in reducing these symptoms in healthy post-menopausal women, but this has never been studied in a large breast cancer population. OBJECTIVES: The primary objective of LIBERATE trial was to study safety of tibolone 2.5mg daily versus placebo as primary, in symptomatic breast cancer survivors. The aim of this present paper was to report effects of tibolone on climacteric symptoms, vaginal dryness and health-related quality of life in the study population. This trial is registered with ClinicalTrials.gov, n. NCT00408863. METHODS: The trial was conducted between June 2002 and July 2007. Concerning quality of life variables, a daily Diary Cards during the first three months and the Climacteric Symptoms Form and at each visit were used to register frequency and intensity of hot flushes. Mean vaginal dryness scores were calculated on the basis of individual ratings at baseline and at week 104. A subset of patients assessed their quality of life filling in the Women's Health Questionnaire (WHQ). RESULTS: Of the 3148 women recruited, 3133 received trial medication (1575 in the tibolone group and 1558 in the placebo group). The median duration of treatment was 2.75 years. In total 3098 women (1556 on tibolone, 1542 on placebo) were included in the intention-to-treat (ITT) population for efficacy analysis. Data on vaginal dryness are available for 2144 patients and 883 women (438 on tibolone, 445 on placebo) answered to WHQ. The mean change in number of hot flushes per day was 2.74 (43.1%) in the tibolone group and -1.77 (-27.5%) in the placebo group (p<0.0001) at week 12 and -4.62 (-65.6%) on tibolone as compared to -3.73 (-52.5%) on placebo (p<0.0001) at week 104. For the composite score the mean changes at week 12 were -0.19 (-10.6%) and -0.14 (-7.7%), respectively (p=0.0006). Vaginal dryness score improved at week 104 in the tibolone group as compared to placebo (-0.46 versus -0.29, respectively; p<0.0001). Across the assessments up to two years with WHQ, tibolone was more effective than placebo in improving sexual health, sleep quality and mood domains. Women using tamoxifen showed less improvement in climacteric symptoms with tibolone, than women only receiving tibolone without any adjuvant therapy. CONCLUSION: The results of the LIBERATE trial show that tibolone is effective in symptomatic breast cancer patients and improves their quality of life. However, this finding should be judged within the context of the main outcome of the trial, showing that tibolone increases the risk of recurrence. The use of tibolone in women with breast cancer will remain contraindicated and any off-label use incurs a now proven risk.

Safety and efficacy of tibolone in breast-cancer patients with vasomotor symptoms: a double-blind, randomised, non-inferiority trial.

BACKGROUND: Vasomotor symptoms and bone loss are complications frequently induced by adjuvant treatment for breast cancer. Tibolone prevents both side-effects, but its effect on cancer recurrence is unknown. The aim of this study was to show non-inferiority of tibolone to placebo regarding risk of recurrence in breast-cancer patients with climacteric complaints. METHODS: Between July 11, 2002, and Dec 20, 2004, women surgically treated for a histologically confirmed breast cancer (T(1-3)N(0-2)M(0)) with vasomotor symptoms were randomly assigned to either tibolone 2.5 mg daily or placebo at 245 centres in 31 countries. Randomisation was done by use of a centralised interactive voice response system, stratified by centre, with a block size of four. The primary endpoint was breast-cancer recurrence, including contralateral breast cancer, and was analysed in the intention-to-treat (ITT) and per-protocol populations; the margin for non-inferiority was set as a hazard ratio of 1.278. This study is registered with ClinicalTrials.gov, number NCT00408863. FINDINGS: Of the 3148 women randomised, 3098 were included in the ITT analysis (1556 in the tibolone group and 1542 in the placebo group). Mean age at randomisation was 52.7 years (SD 7.3) and mean time since surgery was 2.1 years (SD 1.3). 1792 of 3098 (58%) women were node positive and 2185 of 3098 (71%) were oestrogen-receptor positive. At study entry, 2068 of 3098 (67%) women used tamoxifen and 202 of 3098 (6.5%) women used aromatase inhibitors. The mean daily number of hot flushes was 6.4 (SD 5.1). After a median follow-up of 3.1 years (range 0.01-4.99), 237 of 1556 (15.2%) women on tibolone had a cancer recurrence, compared with 165 of 1542 (10.7%) on placebo (HR 1.40 [95% CI 1.14-1.70]; p=0.001). Results in the per-protocol population were similar (209 of 1254 [16.7%] women in the tibolone group had a recurrence vs 138 of 1213 [11.4%] women in the placebo group; HR 1.44 [95% CI 1.16-1.79]; p=0.0009). Tibolone was not different from placebo with regard to other safety outcomes, such as mortality (72 patients vs 63 patients, respectively), cardiovascular events (14 vs 10, respectively), or gynaecological cancers (10 vs 10, respectively). Vasomotor symptoms and bone-mineral density improved significantly with tibolone, compared with placebo. INTERPRETATION: Tibolone increases the risk of recurrence in breast cancer patients, while relieving vasomotor symptoms and preventing bone loss. FUNDING: Schering-Plough (formerly NV Organon, Oss, Netherlands).

Endometrial effects of tibolone in elderly, osteoporotic women.

OBJECTIVE: To investigate endometrial effects of tibolone administered to postmenopausal women for 3 years. METHODS: Postmenopausal women (N=3,519) aged 60-85 years (mean 68 years) with a uterus and with osteoporosis were randomly assigned to receive tibolone orally, 1.25 mg per day, or identical placebo. We evaluated effects on endometrial thickness in all women, and examined endometrial histology in 635 participants considered to be at increased risk for abnormalities (with unexpected vaginal bleeding or endometrial thickness more than 4 mm). RESULTS: During the first year of study, mean endometrial thickness increased 1 mm in women receiving tibolone (P<.001), but no further increases were noted during the next 2 years. Diagnostic biopsies among 499 women receiving tibolone and 136 who were receiving placebo showed cumulative incidences of endometrial hyperplasia less than 1%. Among the 15% of women whose biopsy showed an endometrial polyp (similar rate in tibolone and placebo), those receiving tibolone were more than twice as likely to show hyperplasia within the polyp. A marginal increase in grade 1 endometrioid adenocarcinoma (P=.06 compared with placebo) was found among women receiving tibolone. Prevalences of vaginal bleeding during the study were 10.8% in the tibolone group and 2.8% in the placebo group (P<.001). CONCLUSION: Tibolone treatment during 3 years minimally increased endometrial thickness, hyperplastic polyps, endometrial carcinoma, and vaginal bleeding.

The effects of tibolone in older postmenopausal women.

BACKGROUND: Tibolone has estrogenic, progestogenic, and androgenic effects. Although tibolone prevents bone loss, its effects on fractures, breast cancer, and cardiovascular disease are uncertain. METHODS: In this randomized study, we assigned 4538 women, who were between the ages of 60 and 85 years and had a bone mineral density T score of -2.5 or less at the hip or spine or a T score of -2.0 or less and radiologic evidence of a vertebral fracture, to receive once-daily tibolone (at a dose of 1.25 mg) or placebo. Annual spine radiographs were used to assess for vertebral fracture. Rates of cardiovascular events and breast cancer were adjudicated by expert panels. RESULTS: During a median of 34 months of treatment, the tibolone group, as compared with the placebo group, had a decreased risk of vertebral fracture, with 70 cases versus 126 cases per 1000 person-years (relative hazard, 0.55; 95% confidence interval [CI], 0.41 to 0.74; P<0.001), and a decreased risk of nonvertebral fracture, with 122 cases versus 166 cases per 1000 person-years (relative hazard, 0.74; 95% CI, 0.58 to 0.93; P=0.01). The tibolone group also had a decreased risk of invasive breast cancer (relative hazard, 0.32; 95% CI, 0.13 to 0.80; P=0.02) and colon cancer (relative hazard, 0.31; 95% CI, 0.10 to 0.96; P=0.04). However, the tibolone group had an increased risk of stroke (relative hazard, 2.19; 95% CI, 1.14 to 4.23; P=0.02), for which the study was stopped in February 2006 at the recommendation of the data and safety monitoring board. There were no significant differences in the risk of either coronary heart disease or venous thromboembolism between the two groups. CONCLUSIONS: Tibolone reduced the risk of fracture and breast cancer and possibly colon cancer but increased the risk of stroke in older women with osteoporosis. (ClinicalTrials.gov number, NCT00519857.)

Effects of tibolone and continuous combined hormone replacement therapy on mammographic breast density.

OBJECTIVE: Our purpose was to compare the effects of tibolone, continuous combined hormone replacement therapy, and placebo on mammographic breast density. STUDY DESIGN: A prospective, randomized, double-blind placebo-controlled study was performed. A total of 166 postmenopausal women were equally randomized to receive tibolone 2.5 mg, estradiol 2 mg/norethisterone acetate 1 mg (E(2)/NETA), or placebo. Mammograms were performed at baseline and after 6 months of treatment. Mammographic density was quantified according to the Wolfe classification and by the percentage area of the breast that had a dense pattern. RESULTS: An increase in mammographic density was much more common among women receiving continuous combined hormone replacement therapy (46%-50%) than among those receiving tibolone (2%-6%) and placebo (0%) treatment. The difference between E(2)/NETA and placebo was highly significant (P <.001). Treatment with tibolone did not differ from that with placebo. The relative risk of an increase in breast density for E(2)/NETA versus tibolone was found to be 8.3 (95% CI 2.7-25.0). CONCLUSION: An increase in mammographic density should be regarded as an unwanted side effect of hormone replacement therapy. In contrast to estrogen/progestogen treatment, tibolone seems to exert little stimulation of breast tissue.