Anastrozole versus tamoxifen as first-line therapy in postmenopausal patients with hormone-dependent advanced breast cancer: a prospective, randomized, phase III study. Prospective randomized study of aminoglutethimide (AG) versus medroxyprogesterone acetate (MPA) versus AG+MPA in generalized breast cancer. Letrozole, a new oral aromatase inhibitor: randomised trial comparing 2.5 mg daily, 0.5 mg daily and aminoglutethimide in postmenopausal women with advanced breast cancer. Letrozole International Trial Group (AR/BC3). Second and third line hormonotherapy in advanced post-menopausal breast cancer: a multicenter randomized trial comparing medroxyprogesterone acetate with aminoglutethimide in patients who have become resistant to tamoxifen. Elevated serum c-erbB-2 antigen levels and decreased response to hormone therapy of breast cancer. An open randomised trial of second-line endocrine therapy in advanced breast cancer. comparison of the aromatase inhibitors letrozole and anastrozole. Double-blind, randomized placebo controlled trial of fulvestrant compared with exemestane after prior nonsteroidal aromatase inhibitor therapy in postmenopausal women with hormone receptor-positive, advanced breast cancer: results from EFECT. Hormonal treatment for metastatic breast cancer. An Eastern Cooperative Oncology Group Phase III trial comparing aminoglutethimide to tamoxifen. Open comparative trial of formestane versus megestrol acetate in postmenopausal patients with advanced breast cancer previously treated with tamoxifen. Trial of aminoglutethimide vs hydrocortisone as second-line hormone treatment of advanced breast cancer. A randomised study of CGS 16949A (fadrozole) versus tamoxifen in previously untreated postmenopausal patients with metastatic breast cancer. Double-blind randomised trial comparing the non-steroidal aromatase inhibitors letrozole and fadrozole in postmenopausal women with advanced breast cancer. Letrozole, a new oral aromatase inhibitor for advanced breast cancer: double-blind randomized trial showing a dose effect and improved efficacy and tolerability compared with megestrol acetate. Randomized trial comparing aminoglutethimide with high-dose medroxyprogesterone acetate in therapy for advanced breast carcinoma. Randomized trial of tamoxifen alone or combined with aminoglutethimide and hydrocortisone in women with metastatic breast cancer. Megestrol acetate and aminoglutethimide/hydrocortisone in sequence or in combination as second-line endocrine therapy of estrogen receptor-positive metastatic breast cancer: a Southwest Oncology Group phase III trial. Randomized phase III trial comparing the new potent and selective third-generation aromatase inhibitor vorozole with megestrol acetate in postmenopausal advanced breast cancer patients. North American Vorozole Study Group. Comparison of the selective aromatase inhibitor formestane with tamoxifen as first-line hormonal therapy in postmenopausal women with advanced breast cancer. Fadrozole HCL (CGS-16949A) versus megestrol acetate treatment of postmenopausal patients with metastatic breast carcinoma: results of two randomized double blind controlled multiinstitutional trials. Fadrozole versus megestrol acetate: a double-blind randomised trial in advanced breast cancer. Anastrozole, a potent and selective aromatase inhibitor, versus megestrol acetate in postmenopausal women with advanced breast cancer: results of overview analysis of two phase III trials. Arimidex Study Group. Phase III, double-blind, controlled trial of atamestane plus toremifene compared with letrozole in postmenopausal women with advanced receptor-positive breast cancer. Randomized trial of tamoxifen versus aminoglutethimide and versus combined tamoxifen and aminoglutethimide in advanced postmenopausal breast cancer. Formestane versus megestrol acetate in postmenopausal breast cancer patients after failure of tamoxifen: a phase III prospective randomised cross over trial of second-line hormonal treatment (SAKK 20/90). Swiss Group for Clinical Cancer Research (SAKK) First-line fadrozole HCI (CGS 16949A) versus tamoxifen in postmenopausal women with advanced breast cancer. Prospective randomised trial of the Swiss Group for Clinical Cancer Research SAKK 20/88. Anastrozole is superior to tamoxifen as first-line therapy in hormone receptor positive advanced breast carcinoma. Megestrol acetate versus aminoglutethimide for metastatic breast cancer. Mature results of a randomized phase II multicenter study of exemestane versus tamoxifen as first-line hormone therapy for postmenopausal women with metastatic breast cancer. Phase III, multicenter, double-blind, randomized study of letrozole, an aromatase inhibitor, for advanced breast cancer versus megestrol acetate. Fulvestrant (Faslodex) versus anastrozole for the second-line treatment of advanced breast cancer in subgroups of postmenopausal women with visceral and non-visceral metastases: combined results from two multicentre trials. Exemestane is superior to megestrol acetate after tamoxifen failure in postmenopausal women with advanced breast cancer: results of a phase III randomized double-blind trial. The Exemestane Study Group.
A prospective phase III trial comparing anastrozole with tamoxifen as first-line therapy in postmenopausal, hormone-dependent, advanced breast cancer (ABC). Patients were randomized to anastrozole 1 mg daily (n = 121) or tamoxifen 40 mg daily (n = 117). Efficacy and tolerability were evaluated after 3 months' therapy, and survival was evaluated at median time of follow-up. At a median follow-up of 13.3 months, clinical benefit (CB) was achieved in 83% and 56% of anastrozole and tamoxifen patients, respectively (p < 0.001); median time to disease progression (TTP) in patients achieving CB was 18.0 months and 7.0 months, respectively, (hazard ratio [HR] = 0.13, 95% CI = 0.08-0.20, p < 0.01). At data cutoff, 89% of tamoxifen patients had died, compared with 60% of anastrozole patients; median time to death was 17.4 months and 16.0 months, respectively (HR = 0.64, 95% CI = 0.47-0.86, p = 0.003). Therapy was well tolerated in both groups. Anastrozole showed significant advantages over tamoxifen for CB, median TTP in patients gaining CB, and survival. These data further support routine use of anastrozole as first-line treatment for postmenopausal hormone-dependent ABC. Eighty-five postmenopausal women with metastatic breast cancer were randomized to receive aminoglutethimide (AG), medroxyprogesterone acetate (MPA), or AG+MPA. Patients with aggressive visceral disease were excluded. Response was observed in 36% of the patients in the AG treatment group, 31% in the MPA treatment group, and 47% in the combination treatment group. Statistical analysis showed that the percentage of responders was not different among the three treatment groups. Similarly, the duration of response did not differ. Toxicity of all three regimens was moderate, not necessitating discontinuation of treatment. In conclusion, AG, MPA and the combination of AG+MPA were found to be equally effective therapies for metastatic breast cancer in postmenopausal women with nonaggressive visceral disease. The lack of statistically significant superiority of the combination of AG+MPA suggests that sequential endocrine monotherapies may be more beneficial than combined hormonotherapies for this patient population. The study compares letrozole and aminoglutethimide (AG), a standard therapy for postmenopausal women with advanced breast cancer, previously treated with antioestrogens.
                555 women were randomly assigned letrozole 2.5 mg once daily (n = 185), letrozole 0.5 mg once daily (n = 192) or aminoglutethimide 250 mg twice daily with corticosteroid support (n = 178) in an open-label, multicentre trial. The primary endpoint was objective response rate (ORR), with time events as secondary. ORR was analysed nine months after enrollment of the last patient, while survival was analysed 15 months after the last patient was enrolled. We report the results of these analyses plus an extended period of observation (covering a total duration of approximately 45 months) to determine the duration of response and clinical benefit.
                Overall objective response rates (complete + partial) of 19.5%, 16.7% and 12.4% were seen for letrozole 2.5 mg, 0.5 mg and AG respectively. Median duration of response and stable disease was longest for letrozole 2.5 mg (21 months) compared with letrozole 0.5 mg (18 months) and AG (14 months). Letrozole 2.5 mg was superior to AG in time to progression, time to treatment failure and overall survival. Treatment-related adverse events occurred in fewer patients on letrozole (33%) than on AG (46%). Transient nausea was the most frequent event with letrozole (7% on 0.5 mg, 10% on 2.5 mg, 10% on AG), rash with AG (11%, 1% on 0.5 mg, 3% on 2.5 mg letrozole).
                Letrozole 2.5 mg offers longer disease control than aminoglutethimide and letrozole 0.5 mg in the treatment of postmenopausal women with advanced breast cancer, previously treated with anti-oestrogens. In order to evaluate the efficacy of two different sequences of second and third line hormonotherapy in advanced post-menopausal breast cancer, 257 women aged 36-91 years (mean age: 63.6 years) who had become resistant to tamoxifen (TAM), entered into a multicenter randomized trial comparing two different regimens: 1) Aminoglutethimide (Ag) 500 mg/day with hydrocortisone supplementation from 30 to 60 mg/day; and 2) oral medroxyprogesterone acetate (MPA) 500 mg twice a day. 250 patients were evaluated following second line hormone therapy and, after cross-over, 128 following third line hormonotherapy. No significant difference was observed, during either second or third line therapies, for toxicity, survival, or response rate; however, in both second and third line therapies the median time to progression was significantly longer with Ag therapy. Decisions concerning the use of hormone therapy to treat metastatic breast cancer are made on the basis of the presence of estrogen receptor (ER). Despite the presence of ER, half of patients will not respond to hormone treatment. The purpose of this study was to determine the effect of overexpression of HER-2/neu on the response to hormone therapy.
                Sera from 300 metastatic breast cancer patients with ER-positive (ER+), ER status unknown, or ER-/progesterone receptor-positive (PR+) randomized to receive second-line hormone therapy with either megestrol acetate or fadrozole were evaluated. An enzyme immunoassay (EIA) specific for the extracellular domain of the c-erbB-2 (HER-2/neu) oncogene product was used to detect serum levels.
                Fifty-eight patients (19.3%) had elevated serum c-erbB-2 protein levels, using a selected cut-point of 30 U/mL. The response rate (complete responses [CRs] plus partial responses [PRs] plus stable disease [S]) to endocrine therapy was 40.9% in 242 patients with low serum c-erbB-2 levels and only 20.7% in 58 patients with elevated serum c-erbB-2 levels (P = .004). The median duration of treatment response was longer in the group with low serum c-erbB-2 levels (15.5 months) compared with the group with elevated serum c-erbB-2 levels (11.6 months). Survival was also significantly shorter in patients with elevated serum c-erbB-2 levels (P < .0001).
                Patients with ER+/c-erbB-2+ metastatic breast cancer are less likely to respond to hormone treatment than ER+/c-erbB-2- patients. Their survival duration is also shorter. It was previously shown that letrozole (Femara) was significantly more potent than anastrozole (Arimidex) in inhibiting aromatase activity in vitro and in inhibiting total body aromatisation in patients with breast cancer. The objective of this study was to compare letrozole (2.5 mg per day) and anastrozole (1 mg per day) as endocrine therapy in postmenopausal women with advanced breast cancer previously treated with an anti-oestrogen. This randomised, multicentre and multinational open-label phase IIIb/IV study enrolled 713 patients. Treatment was for advanced breast cancer that had progressed either during anti-oestrogen therapy or within 12 months of completing that therapy. Patients had tumours that were either positive for oestrogen and/or progesterone receptors (48%) or of unknown receptor status (52%). The primary efficacy endpoint was time to progression (TTP). Secondary endpoints included objective response, duration of response, rate and duration of overall clinical benefit (responses and long-term stable disease), time to treatment failure, and overall survival, as well as general safety. There was no difference between the treatment arms in TTP; median times were the same for both treatments. Letrozole was significantly superior to anastrozole in the overall response rate (ORR) (19.1% versus 12.3%, P=0.013), including in predefined subgroups (receptor status-unknown, and soft-tissue- and viscera-dominant site of disease). There were no significant differences between the treatment arms in the rate of clinical benefit, median duration of response, duration of clinical benefit, time to treatment failure or overall survival. Both agents were well tolerated and there were no significant differences in safety. These results support previous data documenting the greater aromatase-inhibiting activity of letrozole and indicate that advanced breast cancer is more responsive to letrozole than to anastrozole as second-line endocrine therapy. The third-generation nonsteroidal aromatase inhibitors (AIs) are increasingly used as adjuvant and first-line advanced therapy for postmenopausal, hormone receptor-positive (HR+) breast cancer. Because many patients subsequently experience progression or relapse, it is important to identify agents with efficacy after AI failure.
                Evaluation of Faslodex versus Exemestane Clinical Trial (EFECT) is a randomized, double-blind, placebo controlled, multicenter phase III trial of fulvestrant versus exemestane in postmenopausal women with HR+ advanced breast cancer (ABC) progressing or recurring after nonsteroidal AI. The primary end point was time to progression (TTP). A fulvestrant loading-dose (LD) regimen was used: 500 mg intramuscularly on day 0, 250 mg on days 14, 28, and 250 mg every 28 days thereafter. Exemestane 25 mg orally was administered once daily.
                A total of 693 women were randomly assigned to fulvestrant (n = 351) or exemestane (n = 342). Approximately 60% of patients had received at least two prior endocrine therapies. Median TTP was 3.7 months in both groups (hazard ratio = 0.963; 95% CI, 0.819 to 1.133; P = .6531). The overall response rate (7.4% v 6.7%; P = .736) and clinical benefit rate (32.2% v 31.5%; P = .853) were similar between fulvestrant and exemestane respectively. Median duration of clinical benefit was 9.3 and 8.3 months, respectively. Both treatments were well tolerated, with no significant differences in the incidence of adverse events or quality of life. Pharmacokinetic data confirm that steady-state was reached within 1 month with the LD schedule of fulvestrant.
                Fulvestrant LD and exemestane are equally active and well-tolerated in a meaningful proportion of postmenopausal women with ABC who have experienced progression or recurrence during treatment with a nonsteroidal AI. Tamoxifen and aminoglutethimide are two hormone therapies reported to be effective palliative approaches for patients with metastatic breast cancer. The current trial was designed to evaluate their relative therapeutic effectiveness.
                Two hundred forty-nine postmenopausal women with advanced breast cancer were randomized in an Eastern Cooperative Oncology Group (ECOG) Phase III study to treatment with adrenalectomy, aminoglutethimide, or tamoxifen with crossover to alternate therapy if disease progressed. Adrenalectomy was dropped as a treatment after 2 years because of low patient accrual.
                There were 216 evaluable patients entered in the study with 108 initially randomized to aminoglutethimide and 108 to receive tamoxifen therapy. The overall response rate for aminoglutethimide was 45%, and for tamoxifen it was 27%. One institution had a response rate of 60% with aminoglutethimide and only 4% with tamoxifen, whereas all of the other institutions combined had a response rate of 41% with aminoglutethimide and 34% with tamoxifen. Eighty-seven evaluable patients crossed over to the other drug (44 to aminoglutethimide and 43 to tamoxifen). There was a 36% response rate to aminoglutethimide and 19% to tamoxifen, with stable disease in 36% of both groups. The overall survival rates were identical. Toxicity was greater with aminoglutethimide (dermatitis) but was not life-threatening. Glucocorticoid support with either dexamethasone or hydrocortisone was acceptable.
                Both aminoglutethimide and tamoxifen produced responses in postmenopausal patients with breast cancer, and a significant number of crossover responses were observed. Of interest in this randomized study was the observation that one institution had a markedly different response rate on induction, reinforcing the need for multi-institution trials in Phase III studies. The aim of the trial was to compare efficacy and safety of the aromatase inhibitor formestane (250 mg i.m. given every 2 weeks) with the progestin megestrol acetate (160 mg administered orally once daily), as second-line therapy in postmenopausal patients with advanced breast cancer previously treated with tamoxifen. A total of 547 patients were enrolled. Analyses revealed no statistically significant or clinically relevant difference between treatments with respect to time endpoints. In the intent-to-treat analysis, the median values for time to failure and overall survival for formestane were 169 and 561 days, respectively. The corresponding values for megestrol acetate were 169 days and 597 days, respectively. Overall response rates were comparable for formestane and megestrol acetate (16.3% vs 20.3%). Formestane was better tolerated than megestrol acetate. In the megestrol acetate group, cardiovascular events, weight increase, and vaginal haemorrhage were significantly more frequent than in the formestane group. Thus, formestane is a suitable alternative to progestins in patients previously treated with tamoxifen. In a randomized trial of second line hormone therapy 56 postmenopausal women with advanced breast cancer received low dose aminoglutethimide (AGT) 125 mg twice daily without hydrocortisone (27 patients), or hydrocortisone (HC) 20 mg twice daily (29 patients). The two groups were well-matched for previous response to tamoxifen (TAM) therapy (AGT (35%) vs HC (32%)) and for relapse on adjuvant TAM. The mean age of the two groups was 69.2 years (AGT) and 63.2 years (HC). Liver metastases were present in 29% (AGT) and 33% (HC). The response rates were 11% (AGT) and 21% (HC). At 12 months the failure of treatment rate was 80% (AGT) and 70% (HC). Survival at 12 months was 50% for both groups. At 12 months 5/12 survivors were still on AGT and 8/12 on HC. These preliminary findings have so far failed to show any statistical difference in tumour response, time to treatment failure or survival between low-dose AGT and HC as second-line hormone treatment post-tamoxifen in advanced breast cancer. Fadrozole, a potent, highly specific inhibitor of aromatase activity, has only been used as second-line therapy in treatment of post-menopausal women with advanced breast cancer. A prospectively randomised study was therefore undertaken to compare relative clinical efficacy of fadrozole as first-line treatment to that of tamoxifen.
                Eighty postmenopausal women who had not received prior treatment for advanced/metastatic breast cancer were randomised to receive either fadrozole, 1 mg twice daily, or tamoxifen, 20 mg daily.
                Toxicity was not statistically different on the two treatment arms. Only mild to moderate toxicity was documented: hot flashes in 37%, headaches in 6.5%, mild fatigue in 2.6%. There were also no statistically significant differences in objective response rates, survival or time to treatment failure (TTF). Objective response rate on fadrozole was 50% (complete response (CR) 8.3% and partial response (PR) 42%). On tamoxifen objective response was 44.7% (CR 21% and PR 24%). Median TTF was 4.9 months on fadrozole and 5 months on tamoxifen. Median survival was 22.7 months on fadrozole and 27.5 months on tamoxifen.
                While response rates, survival and TTF were not statistically significantly different, there were more complete responses on tamoxifen and duration of objective response (CR + PR) was significantly longer in the patients treated with tamoxifen. To compare the efficacy, safety and tolerability of letrozole, an advanced non-steroidal aromatase inhibitor, and fadrozole hydrochloride, an older-generation drug in this class, we conducted a randomised double-blind trial in postmenopausal women with advanced breast cancer.
                One hundred and fifty-seven postmenopausal women with advanced breast cancer were enrolled and randomly assigned to receive letrozole or fadrozole in a multicentre, randomised double-blind trial in Japan. One hundred and fifty-four eligible patients were treated with either letrozole 1.0 mg once daily (n = 77) or fadrozole 1.0 mg twice daily (n = 77), for a minimum of 8 weeks.
                Letrozole showed a significantly higher overall objective response rate [complete response (CR) + partial response (PR)] than fadrozole (31.2% and 13.0%, respectively; P = 0.011, Fisher's exact test). Clinical benefits defined as CR, PR and stable disease (no change in status for more than 24 weeks) were also higher in patients treated with letrozole (50.6%) than fadrozole (35.1%). Letrozole was significantly superior to fadrozole in terms of the dominant lesion in soft tissue, bone and viscera (P = 0.011, stratified Mantel-Haenszel test). Median time to progression was 211 days in the letrozole group and 113 days in the fadrozole group with no significant difference (P = 0.175, log-rank test). Letrozole markedly reduced the estradiol, estrone and estrone sulfate levels in peripheral blood within 4 weeks. The suppressive effect of fadrozole on these hormone levels was insufficient. Adverse drug reactions were observed in 35.9% of the patients treated with letrozole and in 39.5% of those treated with fadrozole with no significant difference between the two groups (P = 0.74, Fisher's exact test). Most of the adverse drug reactions were rated as grade 1 or 2.
                The results show letrozole at a dose of 1.0 mg once daily to be more effective in treating postmenopausal women with advanced breast cancer than fadrozole at 1.0 mg twice daily, with similar safety and tolerability profiles. To compare two doses of letrozole and megestrol acetate (MA) as second-line therapy in postmenopausal women with advanced breast cancer previously treated with antiestrogens.
                Five hundred fifty-one patients with locally advanced, locoregionally recurrent or metastatic breast cancer were randomly assigned to receive letrozole 2.5 mg (n = 174), letrozole 0.5 mg (n = 188), or MA 160 mg (n = 189) once daily in a double-blind, multicenter trial. Data were analyzed for tumor response and safety variables up to 33 months of follow-up evaluation and for survival up to 45 months.
                Letrozole 2.5 mg produced a significantly higher overall objective response rate (24%) compared with MA (16%; logistic regression, P = .04) or letrozole 0.5 mg (13%; P = .004). Duration of objective response was significantly longer for letrozole 2.5 mg compared with MA (Cox regression, P = .02). Letrozole 2.5 mg was significantly superior to MA and letrozole 0.5 mg in time to treatment failure (P = .04 and P = .002, respectively). For time to progression, letrozole 2.5 mg was superior to letrozole 0.5 mg (P = .02), but not to MA (P = .07). There was a significant dose effect in overall survival in favor of letrozole 2.5 mg (P = .03) compared with letrozole 0.5 mg. Letrozole was significantly better tolerated than MA with respect to serious adverse experiences, discontinuation due to poor tolerability, cardiovascular side effects, and weight gain.
                The data show letrozole 2.5 mg once daily to be more effective and better tolerated than MA in the treatment of postmenopausal women with advanced breast cancer previously treated with antiestrogens. A total of 218 postmenopausal patients were entered in a prospective randomized trial comparing aminoglutethimide (AG) and high-dose medroxyprogesterone acetate (MPA) as second-line hormonal therapy for advanced breast carcinoma. All responses were assessed by the criteria of the International Union Against Cancer. The response rates were 27% (29 of 106 patients) for AG and 31% (35 of 112) for MPA, but if stabilization of previously progressive disease is included, then the overall response rates were 51% (54 of 106) and 54% (61 of 112) for patients receiving AG or MPA, respectively. There was no difference in response to the two drugs at any site of disease, and the durations of response and survival were identical for the two drugs. The time to response was significantly shorter for patients treated with MPA (median, 8.7 wk) than for those treated with AG (median, 15.3 wk) (chi 2 = 9.96, 1 df, P = .0016). The percentage of patients experiencing toxic effects was equivalent in both arms, although the patterns and time courses of these effects were different. A randomized clinical trial was performed to compare the efficacy of tamoxifen (TAM) alone with that of TAM plus aminoglutethimide (AG) and hydrocortisone (HC). Patients failing TAM could receive AG and HC. Objective responses to therapy were seen in 21 of 49 TAM patients (43%) and 25 of 51 TAM, AG and HC patients (49%). Time to disease progression and survival distributions were not significantly different between the treatment arms. Toxicity was greater for patients treated with TAM, AG, and HC and the trial was discontinued early for this reason. Twenty-four patients received AG and HC after TAM therapy and three (12%) achieved a response. We conclude that the combination of TAM, AG, and HC is not recommended over TAM alone because toxicity appears to outweigh any potential therapeutic advantage. A phase III randomized trial was performed to determine whether combination hormonal therapy with aminoglutethimide (AG) and hydrocortisone (HC) plus megestrol acetate (MA) improved response rates, response duration, or increased survival over the sequential use of each hormone in women with estrogen receptor-positive metastatic breast cancer (MBC) who had maintained stable disease for at least 6 months or responded to tamoxifen.
                Two hundred eighty-eight postmenopausal women with progressive estrogen receptor-positive MBC were randomly selected to receive MA 40 mg four times daily (arm I), AG 250 mg four times daily with HC 40 mg daily in divided doses (arm II), versus the combination of MA plus AG given at the same dosages (arm III). Patients on arms I and II who progressed after an adequate trial were crossed over to the other treatment arm.
                Two hundred thirty-five eligible patients were evaluated for response, time to treatment failure, and survival. Response was only reported for patients with measurable disease and was not statistically different among the three arms. There were two partial responses (PRs) on MA (6%), four complete responses (CRs) and six PRs on AG (24%), and eight PRs and three CRs on MA plus AG (23%) in 32, 42, and 48 measurable patients, respectively. Median times to treatment failure were also similar at 5, 4, and 7 months. Survival was also not statistically different among the three arms at 26, 27, and 26 months for arms I, II, and III, respectively. Toxicity was greater in the two AG arms with respect to fatigue, nausea and vomiting, and rash.
                With the exception of toxicity, there is no response, time to treatment failure, or survival benefit for any one group when comparing MA, AG, or the combination at their stated doses in women with estrogen receptor-positive MBC who had previously responded to or stabilized with tamoxifen. To compare the efficacy and safety of vorozole (VOR) 2.5 mg once daily with that of megestrol acetate (MA) 40 mg four times per day as second-line therapy in postmenopausal women with advanced breast cancer whose disease progressed after tamoxifen treatment.
                A total of 452 patients were enrolled onto an open, multicenter, randomized phase III trial comparing VOR to MA for tumor response, safety, and quality of life (as indicated by the Functional Living Index-Cancer score).
                Vorozole produced a response rate of 9.7%, compared with 6.8% for MA (P = .24). Clinical benefit (complete response + partial response + no change in > 6 months) was demonstrated in 23.5% and 27.2% of patients treated with VOR and MA, respectively (P = .42). Median duration of response was 18.2 months for VOR versus 12.5 months for MA (P = .074). There was no significant difference in time to progression or survival between the treatment groups. Discontinuation of treatment because of adverse events occurred less frequently in the VOR-treated group (3.1% v 6.2%; P = .18). Patients on the VOR arm reported significantly more nausea, hot flushes, arthralgia, upper respiratory tract infection, anorexia, and paresthesia, whereas those treated with MA had significantly more dyspnea, increased appetite, and weight increase. There was no difference between the two treatment groups in Functional Living Index-Cancer scores (total or subscales). However, when analyzed by objective response, patients with complete or partial responses (P = .032) or no change (P = .033) who were receiving VOR had significant improvement in the psychologic well-being subscale, compared with patients given MA.
                Vorozole is well tolerated and as effective as MA in the treatment of postmenopausal advanced breast cancer patients with disease progression after tamoxifen treatment. A total of 409 postmenopausal patients with advanced metastatic breast cancer were randomized to receive either formestane (Lentaron) 250 mg every 2 weeks by intramuscular injection, or tamoxifen 30 mg/day orally. Treatment continued until tumor progression. The groups were well matched for pretreatment characteristics including age, performance status, hormone receptor status (patients with known negative receptor status of their primary tumor were excluded), site and extent of metastases, disease-free interval, and previous primary and adjuvant therapy. Patients were assessed for antitumor efficacy at 3-monthly intervals using UICC criteria. Of the 348 patients evaluable for response, 33% had an objective response to formestane (14 complete and 43 partial responses), while 37% had an objective response to tamoxifen (10 complete and 54 partial responses). Median duration of response was 15 months for formestane and 20 months for tamoxifen; survival was 35 and 38 months respectively. There were no statistically significant differences between the treatments for all these variables, but time to disease progression and time to treatment failure significantly favoured tamoxifen. Systemic tolerability was excellent for both treatments. Local side effects due to intramuscular injection of formestane were mild and transient. In this comparative trial of first-line therapy for advanced breast cancer, formestane gave results comparable to tamoxifen for both efficacy and tolerability. We conclude that formestane is an effective and well tolerated addition to the therapeutic options available for the treatment of postmenopausal women with advanced breast cancer. Breast cancer patients with prior response to endocrine therapy achieve subsequent benefit from additional endocrine therapies. The efficacy and safety of an aromatase inhibitor, fadrozole HCL, were compared with megestrol acetate in post menopausal patients who had disease progression after receiving antiestrogen therapy either for metastatic disease or as adjuvant therapy.
                In 2 multiinstitutional prospective trials, 683 postmenopausal patients were randomized to receive either fadrozole HCL, 1 mg twice daily, or megestrol acetate, 40 mg 4 times daily, in a double blind fashion after progression on first-line hormonal therapy. Objective response rates, time to progression, survival and safety of the two regimens were compared.
                Results of intent-to-treat analyses are presented in this study. No significant differences were detected between the two treatment groups in time to progression, objective response rates, duration of response, and survival in either trial. There were no clinically meaningful differences between the treatment groups in the incidence and severity of adverse experiences, except that weight gain, fluid retention, and dyspnea were observed in more patients in the megestrol acetate group compared with those receiving fadrozole HCL, whereas nausea and vomiting were observed in more patients in the fadrozole HCL group compared with those receiving megestrol acetate.
                Fadrozole HCL was as efficacious as megestrol acetate in postmenopausal patients with metastatic breast carcinoma after one hormonal therapy. Adverse experiences were mild with both therapies, but megestrol acetate was associated wiht a higher frequency of weight gain, fluid retention and dyspnea, whereas fadrozole HCL was associated with a higher frequency of nausea and vomiting. Ninety-six patients were entered into a randomised, double-blind, double-dummy, clinical trial to assess the efficacy and safety of fadrozole as compared to megestrol acetate as second-line hormonal treatment for patients with advanced breast cancer. Analysis of results was on an intention-to-treat basis and included response rate, time to progression (TTP), time to treatment failure (TTF) and survival. Forty-six patients received fadrozole and 50 were randomised to megestrol acetate. Patients and pretreatment prognostic variables were balanced in the two arms of the trial. The objective response rates [3/46 (7%) for fadrozole and 3/50 (6%) for megestrol acetate], TTP, TTF and survival were similar in the two arms of the trial. Toxicity was also similar in the two arms of the trial and consisted mainly of oedema, hypertension and minor gastrointestinal symptoms. Fadrozole appears to be as active as megestrol acetate in second-line hormonal treatment of advanced breast cancer. To compare the efficacy and tolerability of anastrozole (1 and 10 mg once daily), a selective, oral, nonsteroidal aromatase inhibitor, and megestrol acetate (40 mg four times daily), in postmenopausal women who progressed following tamoxifen treatment.
                Two randomized, double-blind for anastrozole, open-label for megestrol acetate, parallel-group, multicenter trials were conducted in 764 patients. Because both trials were identical in design, an analysis of the combined results was performed to strengthen interpretation of results from each trial.
                The median follow-up duration was approximately 6 months. The estimated progression hazards ratios were 0.97 (97.5% confidence interval [CI], 0.75 to 1.24) for anastrozole 1 mg versus megestrol acetate and 0.92 (97.5% CI, 0.71 to 1.19) for anastrozole 10 mg versus megestrol acetate. The overall median time to progression was approximately 21 weeks. Approximately one third of patients in each group benefited from treatment. Twenty-seven patients (10.3%) in the anastrozole 1-mg group, 22 (8.9%) in the anastrozole 10-mg group, and 20 (7.9%) in the megestrol acetate group had a complete or partial response, and 66 (25.1%), 56 (22.6%), and 66 (26.1%) patients, respectively, had stable disease for > or = 24 weeks. For all end points, individual trial results were similar to the results of the combined analysis. Anastrozole and megestrol acetate were well tolerated. Gastrointestinal disturbance was more common among patients in the anastrozole groups than the megestrol acetate group; the difference between the anastrozole 10 mg and megestrol acetate groups was significant (P = .005). Significantly fewer patients in the anastrozole 1-mg (P < .0001) and 10-mg (P < .002) groups had weight gain than in the megestrol acetate group. More than 30% of megestrol acetate-treated patients had weight gain > or = 5%, and 10% of patients had weight gain > or = 10%. Patients who received megestrol acetate continued to gain weight over time.
                Anastrozole, 1 and 10 mg once daily, is well tolerated and as effective as megestrol acetate in the treatment of postmenopausal women with advanced breast cancer who progressed following tamoxifen treatment. Moreover, anastrozole therapy avoids the weight gain associated with megestrol acetate treatment. To compare time to progression (TTP) with a steroidal aromatase inhibitor (AI) atamestane (ATA) combined with toremifene (TOR; complete estrogen blockade) versus letrozole (LET) in receptor-positive advanced breast cancer (ABC).
                Eligibility included postmenopausal receptor-positive ABC and adjuvant hormonal therapy completed more than 12 months prior to study entry. Participants received daily ATA 500 mg with TOR 60 mg (ATA + TOR), or letrozole 2.5 mg (LET). The primary end point was TTP, whereas secondary objectives included objective response (OR), overall survival (OS), and time to treatment failure (TTF). The study had 80% power to detect a 25% increase in TTP assuming a TTP of 9.4 months in the LET population.
                A total of 865 patients were randomly assigned (434 to ATA + TOR and 431 to LET) in 60 centers in the United States, Canada, Russia, and Ukraine. Baseline characteristics were balanced. Median TTP was identical in the two arms at 11.2 months (P < .92). Median TTF was similar at 9.24 months (ATA + TOR) versus 10.44 months (LET). The hazard ratios (LET/ATA + TOR) were 1.00 (95% CI, 0.92 to 1.08) for TTP, 0.99 (95% CI, 0.92 to 1.06) for TTF, and 0.98 (95% CI, 0.87 to 1.11) for OS. OR occurred in 30% of patients receiving ATA + TOR and in 36% of patients receiving LET (P < .1). Adverse events (AEs) were similar for patients receiving ATA + TOR versus LET, and serious AEs were 10% v 11%, respectively.
                TTP for patients receiving ATA + TOR was identical to that for patients receiving LET, representing the first endocrine therapy comparable to LET in ABC. Unlike in the Anastrozole, Tamoxifen, and Combined trial, addition of an antiestrogen did not decrease efficacy of the AI. Future studies of AIs in combination with more effective selective estrogen receptor modulators or selective receptor downregulators is warranted. In a randomized trial, 105 postmenopausal women with advanced carcinoma of the breast received tamoxifen or aminoglutethimide or combined tamoxifen and aminoglutethimide. No differences were found in the rate of responses and duration of responses between the treatment groups. Toxicity was significantly greater (p less than 0.01) in patients who received aminoglutethimide. The aim of the study was to compare efficacy and tolerability of the new aromatase inhibitor formestane (Lentaron) with megestrol acetate (Megestat) (MGA) in postmenopausal patients with advanced breast cancer. 179 patients were randomised to receive either 250 mg formestane intramuscularly biweekly or MGA 160 mg orally daily. 51% of the patients had received tamoxifen as adjuvant treatment; 73% of the patients had positive and 16% unknown oestrogen receptor values. The response rate was 17% in both treatment arms (95% confidence interval 10-26% for formestane and 10-27% for MGA). Disease stabilisation > or = 6 months was seen in 25% of the formestane and 22% of the MGA patients. Time to treatment failure was 120 days in the formestane arm and 111 days in the MGA arm. There was no significant difference between the treatments with regard to response rate and time to treatment failure. Overall toxicity was similar in both arms, but weight gain > 3 kg (P = 0.081) and severe cardiovascular toxicity (P = 0.044) were more frequently observed with MGA, e.g. deep vein thrombosis 0/90 formestane versus 5/81 MGA cases (P = 0.022). Formestane was associated with worsening of hot flushes/sleeping problems (P = 0.051) and mild leucopenia (P = 0.004). In our study, formestane and MGA showed similar antineoplastic activity as second-line hormonal treatment for advanced breast cancer. Both drugs have a specific toxicity profile. MGA was associated with significantly more severe cardiovascular toxicity and weight increase than formestane. In a phase III randomized trial, we compared the effectiveness and tolerability of fadrozole (CGS 16949A), a non-steroidal aromatase inhibitor, to tamoxifen as first-line endocrine therapy in postmenopausal women with advanced breast cancer.
                Two hundred twelve eligible patients were randomized to receive tamoxifen 20 mg daily, or fadrozole 1 mg twice daily orally until disease progression or the advent of undue toxicity. The treatments were to be discontinued upon disease progression.
                Prognostic factors were well balanced between the treatment groups, except for sites of metastatic disease. Fadrozole-treated patients had significantly more visceral, especially liver, involvement and less bone-dominant disease. Response rates for fadrozole and tamoxifen were similar, 20% and 27% (95% Confidence Limits (CL): 13%-29% and 21%-35%), respectively. Time to treatment failure was longer in patients randomized to tamoxifen (8.5 months for tamoxifen vs. 6.1 months for fadrozole), but did not reach statistical significance after adjustment for prognostic factors (P = 0.09). Fadrozole, for which a significantly lower percentage of clinically relevant toxic effects (WHO toxicity grade > or = 2) was recorded (27% vs. 13%, respectively; P = 0.009), was better tolerated than tamoxifen. Severe cardiovascular events including 3 fatalities were seen only in patients treated with tamoxifen. Eighty-two patients crossed over to tamoxifen and 66 patients to fadrozole. Crossover endocrine therapy led to response or stable disease in 64% of the patients. The overall survival times of the two treatment groups were similar.
                Fadrozole and tamoxifen showed similar efficacy as first-line treatments in postmenopausal patients with advanced breast cancer. Fadrozole was significantly better tolerated and may therefore be an appropriate alternative to tamoxifen, especially for patients predisposed to thromboembolic events. Two randomized, double-blind trials have compared tamoxifen 20 mg daily and the selective, nonsteroidal aromatase inhibitor anastrozole 1 mg daily as first-line therapy for advanced breast carcinoma (ABC) in postmenopausal women. The trials were prospectively designed to allow for combined data analyses.
                The combined study population included 1021 postmenopausal women (median age, 67 years [range, 30-92]) with ABC whose tumors were either estrogen and/or progesterone receptor positive or of unknown receptor status. Primary endpoints were time to progression (TTP), objective response, and tolerability.
                At a median duration of follow-up of 18.2 months, anastrozole was at least equivalent to tamoxifen in terms of median TTP (8.5 and 7.0 months, respectively; estimated hazard ratio [tamoxifen relative to anastrozole], 1.13 [lower 95% confidence level, 1.00]). In a retrospective subgroup analysis, anastrozole was superior to tamoxifen with respect to TTP (median values of 10.7 and 6.4 months for anastrozole and tamoxifen, respectively, two-sided P = 0.022) in patients with estrogen and/or progesterone receptor positive tumors (60% of combined trial population). In terms of objective response, 29.0% of anastrozole and 27.1% of tamoxifen patients achieved either a complete response (CR) or a partial response (PR). Clinical benefit (CR + PR + stabilization of > or = 24 weeks) rates were 57.1% and 52.0% for anastrozole and tamoxifen, respectively. Both anastrozole and tamoxifen were well tolerated. Anastrozole led to significantly fewer venous thromboembolic (P = 0.043; not adjusted for multiple comparisons) events, and vaginal bleeding was reported in fewer patients treated with anastrozole than with tamoxifen.
                In postmenopausal women with hormonally sensitive ABC, anastrozole should be considered as the new standard first-line treatment.
                Copyright 2001 American Cancer Society. In this prospective, randomized study the clinical response and toxicity of megestrol acetate (MA) and aminoglutethimide (AG) as second-line treatment in patients with metastatic breast cancer was compared. 176 patients were included, and 150 received treatment greater than 8 weeks and are evaluable for treatment response. The two groups did not differ with regard to prognostic factors. Response rate for the AG and MA groups were 34% and 31% respectively, with duration of response of 13.1 and 13.0 months. Stable disease was obtained in 33% and 35% respectively. No difference was observed in survival. Side effects occurred more frequently in the AG group (42%) than in the MA group (18%). Women with hormone-responsive metastatic breast cancer (MBC) may respond to or have stable disease with a number of hormone therapies. We explored the efficacy and safety of the steroidal aromatase inactivator exemestane as first-line hormonal therapy in MBC in postmenopausal women.
                Patients with measurable disease were eligible if they had received no prior hormone therapy for metastatic disease and had hormone receptor positive disease or hormone receptor unknown disease with a long disease-free interval from adjuvant therapy. They were randomized to tamoxifen 20 mg/day or exemestane 25 mg/day in this open-label study.
                Blinded independently reviewed response rates for exemestane and tamoxifen were 41% and 17%, respectively. Fifty-seven per cent of exemestane- and 42% of tamoxifen-treated patients experienced clinical benefit, defined as complete or partial response, or disease stabilization lasting at least 6 months. There was a low incidence of severe flushing, sweating, nausea and edema in women who received exemestane. One exemestane-treated patient had a pulmonary embolism with grade 4 dyspnea.
                Exemestane is well tolerated and active in the first-line treatment of hormone-responsive MBC. An ongoing EORTC phase III trial is comparing the efficacy, measuring time-to-disease progression, of exemestane and tamoxifen. To compare two doses of letrozole (0.5 mg and 2.5 mg every day) and megestrol acetate (40 mg qid) as endocrine therapy in postmenopausal women with advanced breast cancer previously treated with antiestrogens.
                This double-blind, randomized, multicenter, multinational study enrolled 602 patients, all of whom were included in the primary analysis in the protocol. Patients had advanced or metastatic breast cancer with evidence of disease progression while receiving continuous adjuvant antiestrogen therapy, had experienced relapse within 12 months of stopping adjuvant antiestrogen therapy given for at least 6 months, or had experienced disease progression while receiving antiestrogen therapy for advanced disease. Tumors were required to be estrogen receptor- and/or progesterone receptor-positive or of unknown status. Confirmed objective response rate was the primary efficacy variable. Karnofsky Performance Status and European Organization for Research and Treatment of Cancer quality-of-life assessments were collected for 1 year.
                There were no statistically significant differences among the three treatment groups for overall objective tumor response. Patients treated with letrozole 0.5 mg had improvements in disease progression (P =.044) and a decreased risk of treatment failure (P =.018), compared with patients treated with megestrol acetate. Letrozole 0.5 mg showed a trend (P =.053) for survival benefit when compared with megestrol acetate. Megestrol acetate was more likely to produce weight gain, dyspnea, and vaginal bleeding, and the letrozole groups were more likely to experience headache, hair thinning, and diarrhea.
                Given a favorable tolerability profile, once-daily dosing, and evidence of clinically relevant benefit, letrozole is equivalent to megestrol acetate and should be considered for use as an alternative treatment of advanced breast cancer in postmenopausal women after treatment failure with antiestrogens. The efficacy of fulvestrant (Faslodex), a novel oestrogen receptor (ER) antagonist that downregulates the ER and has no known agonist effects, was compared with the aromatase inhibitor anastrozole (Arimidex) for the second-line treatment of advanced breast cancer in postmenopausal women with visceral and non-visceral metastases. Assessment was by means of a retrospective subgroup analysis of combined data from two randomised, phase III trials. Objective response (OR) rates were similar in patients treated with fulvestrant and anastrozole, respectively (21.9% versus 19.3%-patients with no visceral metastases; 15.7% versus 13.2%-all of the patients with visceral metastases; 18.8% versus 14.0%-patients with visceral metastases only). The proportion of patients with clinical benefit (CB) was also similar between treatments and between subgroups with and without visceral disease. Fulvestrant is at least as effective as anastrozole, providing a valuable treatment option for advanced breast cancer in postmenopausal women with visceral metastases who have failed on prior endocrine therapy. This phase III, double-blind, randomized, multicenter study evaluated the efficacy, pharmacodynamics, and safety of the oral aromatase inactivator exemestane (EXE) versus megestrol acetate (MA) in postmenopausal women with progressive advanced breast cancer who experienced failure of tamoxifen.
                A total of 769 patients were randomized to EXE 25 mg/d (n = 366) or MA (n = 403) 40 mg four times daily. Tumor response, duration of tumor control, tumor-related signs and symptoms (TRSS), quality of life (QOL), survival, and tolerability were evaluated.
                Overall objective response (OR) rates were higher in patients treated with EXE than in those treated with MA (15.0% v 12.4%); a similar trend was noted in patients with visceral metastases (13.5% v 10.5%). Median survival time was significantly longer with EXE (median not reached) than with MA (123.4 weeks; P =.039), as were the median duration of overall success (OR or stable disease > or = 24 weeks; 60.1 v 49.1 weeks; P =.025), time to tumor progression (20.3 v 16.6 weeks; P =.037), and time to treatment failure (16.3 v 15.7 weeks; P =.042). Compared with MA, there were similar or greater improvements in pain, TRSS, and QOL with EXE. Both drugs were well tolerated. Grade 3 or 4 weight changes were more common with MA (17.1% v 7.6%; P =.001).
                EXE prolongs survival time, time to tumor progression, and time to treatment failure compared with MA and offers a well-tolerated treatment option for postmenopausal women with progressive advanced breast cancer who experienced failure of tamoxifen.
In women with advanced (metastatic) breast cancer, aromatase inhibitors including those in current clinical use show a survival benefit when compared to other endocrine therapy.