Gemtuzumab ozogamicin for de novo acute myeloid leukemia: final efficacy and safety updates from the open-label, phase III ALFA-0701 trial

The randomized, phase III ALFA-0701 trial showed that a reduced and fractionated dose of gemtuzumab ozogamicin added to standard front-line chemotherapy significantly improves event-free survival (EFS) in adults with de novo acute myeloid leukemia (AML). Here we report an independent review of EFS, final overall survival (OS), and additional safety results from ALFA-0701. Patients (n=271) aged 50-70 years with de novo AML were randomized to receive conventional front-line induction chemotherapy (3+7daunorubicin+cytarabine) with/without gemtuzumab ozogamicin 3 mg/m² on days 1, 4, and 7 during induction. Patients in remission following induction therapy received 2 courses of consolidation therapy (daunorubicin+cytarabine) with/without gemtuzumab ozogamicin (3 mg/m²/day on day 1) according to their initial randomization. The primary end point was investigator-assessed EFS. Secondary end points included OS and safety. A blinded independent review confirmed the investigator-assessed EFS results [August 1, 2011; hazard ratio (HR) 0.66; 95% Confidence Interval (CI): 0.49–0.89; 2-sided P=0.006], corresponding to a 34% reduction in risk of events in the gemtuzumab ozogamicin versus control arm. Final OS at April 30, 2013 favored gemtuzumab ozogamicin but was not significant. No differences in early death rate were observed between arms. The main toxicity associated with gemtuzumab ozogamicin was prolonged thrombocytopenia. Veno-occlusive disease (including after transplant) was observed in 6 patients in the gemtuzumab ozogamicin arm and 2 in the control arm. In conclusion, gemtuzumab ozogamicin added to standard intensive chemotherapy has a favorable benefit/risk ratio. These results expand front-line treatment options for adult patients with previously untreated AML. (Trial registered at clinicaltrials.gov; identifier: 00927498.)

Improved overall survival in melanoma with combined dabrafenib and trametinib

BACKGROUND

The BRAF inhibitors vemurafenib and dabrafenib have shown efficacy as monotherapies in patients with previously untreated metastatic melanoma with BRAF V600E or V600K mutations. Combining dabrafenib and the MEK inhibitor trametinib, as compared with dabrafenib alone, enhanced antitumor activity in this population of patients.

METHODS

In this open-label, phase 3 trial, we randomly assigned 704 patients with metastatic melanoma with a BRAF V600 mutation to receive either a combination of dabrafenib (150 mg twice daily) and trametinib (2 mg once daily) or vemurafenib (960 mg twice daily) orally as first-line therapy. The primary end point was overall survival.

RESULTS

At the preplanned interim overall survival analysis, which was performed after 77% of the total number of expected events occurred, the overall survival rate at 12 months was 72% (95% confidence interval [CI], 67 to 77) in the combination-therapy group and 65% (95% CI, 59 to 70) in the vemurafenib group (hazard ratio for death in the combination-therapy group, 0.69; 95% CI, 0.53 to 0.89; P=0.005). The prespecified interim stopping boundary was crossed, and the study was stopped for efficacy in July 2014. Median progression-free survival was 11.4 months in the combination-therapy group and 7.3 months in the vemurafenib group (hazard ratio, 0.56; 95% CI, 0.46 to 0.69; P<0.001). The objective response rate was 64% in the combination-therapy group and 51% in the vemurafenib group (P<0.001). Rates of severe adverse events and study-drug discontinuations were similar in the two groups. Cutaneous squamous-cell carcinoma and keratoacanthoma occurred in 1% of patients in the combination-therapy group and 18% of those in the vemurafenib group.

CONCLUSIONS

Dabrafenib plus trametinib, as compared with vemurafenib monotherapy, significantly improved overall survival in previously untreated patients with metastatic melanoma with BRAF V600E or V600K mutations, without increased overall toxicity. (Funded by GlaxoSmithKline; ClinicalTrials.gov number, NCT01597908.).

A randomised, double-blind phase III study of pazopanib in patients with advanced and/or metastatic renal cell carcinoma: final overall survival results and safety update

BACKGROUND

In this randomised phase III study (VEG105192; NCT00334282), pazopanib previously demonstrated statistically and clinically meaningful improvement of progression-free survival versus placebo in patients with advanced/metastatic renal cell carcinoma (mRCC). Final overall survival (OS) and updated safety results are now reported.

METHODS

Treatment-naive or cytokine-pretreated mRCC patients (n=435) stratified and randomised (2:1) to pazopanib 800 mg daily or placebo, were treated until disease progression, death or unacceptable toxicity. Upon progression, placebo patients could receive pazopanib through an open-label study. Final OS in the intent-to-treat population was analysed using a stratified log-rank test. Rank-preserving structural failure time (RPSFT) and inverse probability of censoring weighted (IPCW) analyses were performed post-hoc to adjust for crossover.

FINDINGS

The difference in final OS between pazopanib- and placebo-treated patients was not statistically significant (22.9 versus 20.5 months, respectively; hazard ratio [HR]=0.91; 95% confidence interval [CI], 0.71-1.16; one-sided P=.224). Early and frequent crossover from placebo to pazopanib and prolonged duration of crossover treatment confounded the OS analysis. In IPCW analyses, pazopanib decreased mortality (HR=0.504; 95% CI, 0.315-0.762; two-sided P=.002). Similar, albeit non-significant, results were obtained in RPSFT analyses (HR=0.43; 95% CI, 0.215-1.388; two-sided P=.172). Since the last cutoff, cumulative exposure to pazopanib increased by 30%. The pazopanib safety profile showed no new safety signals or changes in the type, frequency and severity of adverse events.

INTERPRETATION

Although no significant difference in OS was observed in this study, extensive crossover from placebo to pazopanib confounded final OS analysis. Post-hoc analyses adjusting for crossover suggest OS benefit with pazopanib treatment for mRCC patients.

A randomized phase II study (VEG108838) of lapatanib plus pazopanib (L+P) versus lapatanib (L) in patients with ErbB2+ inflammatory breast cancer (IBC)

531

Background: ErbB2 amplification is frequently reported in IBC and there is evidence of positive association between ErbB2 and VEGF expression. We evaluated the combination of anti ErbB2 and VEGF therapy in ErbB2+ IBC. Methods: We conducted a multicenter, randomized clinical trial for patients (pts) with relapsed ErbB2+ IBC. Cohort 1: Pts stratified (prior trastuzumab; cutaneous disease only vs systemic) and randomized 1:1 to receive L 1500 mg + placebo or L 1500 mg + P 800 mg, QD. Due to high incidence of Grade 3/4 diarrhea in pts treated with L 1500 mg+ P 800 mg in another study, Cohort 1 was closed after 76 pts randomized. Cohort 2 (87 pts ): Pts were stratified (prior trastuzumab) and randomized 5:5:2 to receive L 1500 mg + placebo or L 1000 mg + P 400 mg (double-blind) or P 800 mg (open-label), respectively, QD. Treatment continued until PD, unacceptable toxicity or death. Primary endpoint was ORR. Secondary endpoints included PFS, OS, and safety. Results: Cohort 1: 76 pts were randomized and treated: L, n=38; L+P, n=38. ORR was 29% for the L arm, and 45% for the L+P arm. Median PFS was 16.1 and 14.3 wks, respectively, for the L and L+P arms. The most frequent Grade ≥3 AEs were diarrhea (0% vs 18%) vomiting (0% vs 8%), ALT increased (0% vs 8%), neutropenia (3% vs 13%), and bilirubin increased (0% vs 5%). Dose reductions due to AE were 3% and 21% and dose interruptions due to AE were 11% and 55% in the L and L+P arms, respectively. Cohort 2: 88 pts were randomized (87 treated): L, n=36; P, n=14; L+P, n=38. The ORR was 47%, 31%, and 58% for the L, P, and L+P arms, respectively. Median PFS was 16.0, 11.4, and 16.0 wks for the L, P, and L+P arms, respectively. The most frequent Grade ≥3 AEs were ALT increased (0%, 0%, 21%), AST increased (0%, 0%, 18%), diarrhea (3%, 8%, 8%), and fatigue (3%, 8%, 8%). Dose reductions due to AE occurred in 0%, 0%, and 13% of pts and dose interruptions due to AE occurred in 22%, 23%, and 39% of pts in the L, P, and L+P arms, respectively. Conclusions: This prospective, randomized study confirmed the clinical activity of lapatinib single agent in metastatic ErbB2+ IBC. Furthermore, we demonstrated increased toxicity associated with the combination without a clinically meaningful improvement in efficacy.

Phase I trial of pegylated liposomal doxorubicin and lapatinib in the treatment of metastatic breast cancer (MBC): Final results

610

Background: Liposomal formulations including pegylated liposomal doxorubicin (PLD) were developed to improve the therapeutic index of anthracyclines (A). Lapatinib (L) is a selective, highly competitive inhibitor of ErbB1 and ErbB2 tyrosine kinases. Conventional doxorubicin plus trastuzumab was effective but with unacceptable cardiac toxicity. PLD plus L may be effective with less cardiac risk. Methods: This is a phase I, dose-escalation trial of PLD 20, 30, 45 and 60 mg/m2 IV every 4 weeks (maximum of 8 doses) and L, 1500 mg po daily until progression in patients (pts) with MBC. ErbB2 positivity was not required. Prior chemotherapy, endocrine therapy and trastuzumab were allowed. A subsequent amendment allowed prior L. Prior A use was limited to 240 mg/m2 of doxorubicin or 600 mg/m2 of epirubicin. Concomitant CYP3A4 inducers/ inhibitors were not allowed. A left ventricular ejection fraction (LVEF) of > 50% was required. The primary objective was to evaluate the safety (particularly cardiac), tolerability and feasibility of PLD and L. Results: 23 pts (PLD: 20 mg/m2 - 4 pts; 30 mg/m2 - 3 pts; 45 mg/m2 – 13 pts; 60 mg/m2- 3 pts) have been treated; total of 73 treatment cycles. Dose-limiting toxicity (DLT) was not reached. One pt had an LVEF drop to < 50% after 4 cycles accompanied by a pericardial effusion due to progressive disease. Treatment-related grade III/IV adverse events included: 4 pts with hand-foot-syndrome (HFS), 2 pts each with leukopenia, infection, and skin changes, 1 pt each with pain, fatigue, diarrhea, mucositis, hypoalbuminemia, anemia, cough, pleural effusion, and edema. Grade 3 HFS occurred in 2 of 3 pts in the 60 mg/m2 cohort. Response data in 21 evaluable pts: 4 PR, 5 SD, and 12 PD. Preliminary pharmacokinetic (PK) analyses (7 pts) indicate L has no effect on PLD (45 mg/m2) concentrations, but L concentrations were approximately 2-fold higher the day of PLD dosing. Conclusions: In 23 pts treated, PLD plus L was well tolerated with manageable toxicities and no treatment-related cardiac toxicity. DLT was not reached however grade 3 HFS occurred in 2 of 3 pts in the 60 mg/m2 cohort. Preliminary PK analyses demonstrate no effect of L on PLD, but an effect of PLD on L the day of PLD dosing.

Lapatinib distribution in HER2 overexpressing experimental brain metastases of breast cancer

PURPOSE

Lapatinib, a small molecule EGFR/HER2 inhibitor, partially inhibits the outgrowth of HER2+ brain metastases in preclinical models and in a subset of CNS lesions in clinical trials of HER2+ breast cancer. We investigated the ability of lapatinib to reach therapeutic concentrations in the CNS following (14)C-lapatinib administration (100 mg/kg p.o. or 10 mg/kg, i.v.) to mice with MDA-MD-231-BR-HER2 brain metastases of breast cancer.

METHODS

Drug concentrations were determined at differing times after administration by quantitative autoradiography and chromatography.

RESULTS

(14)C-Lapatinib concentration varied among brain metastases and correlated with altered blood-tumor barrier permeability. On average, brain metastasis concentration was 7-9-fold greater than surrounding brain tissue at 2 and 12 h after oral administration. However, average lapatinib concentration in brain metastases was still only 10-20% of those in peripheral metastases. Only in a subset of brain lesions (17%) did lapatinib concentration approach that of systemic metastases. No evidence was found of lapatinib resistance in tumor cells cultured ex vivo from treated brains.

CONCLUSIONS

Results show that lapatinib distribution to brain metastases of breast cancer is partially restricted and blood-tumor barrier permeability is a key component of lapatinib therapeutic efficacy which varies between tumors.

Randomized phase II study of lapatinib plus capecitabine or lapatinib plus topotecan for patients with HER2-positive breast cancer brain metastases

Approximately one-third of patients with advanced, HER2-positive breast cancer develop brain metastases. A significant proportion of women experience central nervous system (CNS) progression after standard radiation therapy. The optimal treatment in the refractory setting is undefined. This study evaluated the toxicity and efficacy of lapatinib in combination with chemotherapy among patients with HER2-positive, progressive brain metastases. Patients with HER2-positive breast cancer with progressive brain metastases after trastuzumab and cranial radiotherapy were included. The primary endpoint was CNS objective response, defined as a ≥ 50% volumetric reduction of CNS lesion(s) in the absence of new or progressive CNS or non-CNS lesions, or increasing steroid requirements. The study was closed early after 22 of a planned 110 patients were enrolled due to excess toxicity and lack of efficacy in the lapatinib plus topotecan arm. The objective response rate (ORR) in the lapatinib plus capecitabine arm was 38% (exact 95% confidence interval [CI] 13.9-68.4). No responses were observed in the lapatinib plus topotecan arm. Although the study was stopped prior to full enrollment, some promising indications of CNS activity were noted for lapatinib plus capecitabine. The combination of lapatinib plus topotecan was not active and was associated with excess toxicity.

Abstract 1565: Pazopanib reveals B-Raf regulation of anti-angiogenesis pathways and prevents brain metastatic colonization of HER2+ breast cancer cells

Brain metastases occur in approximately 35% of metastatic breast cancer patients whose tumors overexpress HER2. Using a quantitative model system to study breast cancer brain metastasis, HER2 overexpression increased the brain colonization of a brain seeking subline of MDA-MB-231 cells (231-BR-HER2). Since HER2 has been shown to induce overexpression of VEGF, we hypothesized that the anti-angiogenic drug pazopanib (GW786034) would reduce the metastatic outgrowth of breast cancer cells in the brain. Pazopanib is a multispecific tyrosine kinase inhibitor targeting VEGFR-1, −2, and −3, PDGFR-alpha and beta, and c-kit.

In vitro, pazopanib not only inhibited proliferation of human brain endothelial cells but also the 231-BR tumor cell line (IC50 = 4microM). Pazopanib disrupted the Erk signaling pathway despite the fact that 231-BR cells have a constitutively activated Ras pathway; expressing mutant K-Ras (codon13) and mutant B-Raf (G464V). Interestingly, using either purified B-Raf or cell lysates, we showed that pazopanib could directly inhibit B-Raf kinase activity as shown by a decreased in pMEK1/2. This data identifies a new mechanism of action of pazopanib as a direct inhibitor of B-Raf. Pazopanib inhibition of B-Raf was greater for the wild type enzyme and the G464V mutant than the V600E mutation.

The inhibition of Ras-Raf-ERK pathway by pazopanib was confirmed in vivo in xenograft models using seven different breast carcinoma and melanoma cell lines presenting different genotypes for the Ras-Raf-ERK pathway (mutation in Ras, mutation in B-Raf, overexpression of kinases upstream Ras (HER2) or wild type for the entire pathway). Anti-angiogenic potency in this cell line panel directly correlated with anti-B-Raf activity, suggesting that B-Raf pathways control angiogenic mediator production.

Finally we demonstrated that Pazopanib prevented the outgrowth of brain metastasis. In the brain metastasis mice model, 231-BR-HER2 cells produced a mean of 3.92 large metastases (&gt;300microM) and 101.9 micro metastasis per brain section in the vehicle treated mice. Treatment with 30 mg/kg Pazopanib resulted in a 51% decline to 1.93 large metastases (p=0.0002) and 25% decrease to 76.4 micro metastasis (p=0.07), while treatment with 100 mg/kg resulted in a 73% decline to 1.05 large metastases (p&lt;0.0001) and 39% decline in micro metastasis to 61.7 (p=0.004). These experiments contradict previous research claiming that anti-angiogenic agents promote metastasis, and support a clinical trial for the treatment or prevention of HER2+ brain metastases.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1565.

Multicenter phase II study of lapatinib in patients with brain metastases from HER2-positive breast cancer

PURPOSE

Brain metastases develop in one third of patients with advanced HER2+ breast cancer. Effective therapy for patients with central nervous system (CNS) progression after cranial radiation is extremely limited and represents a major clinical challenge. Lapatinib, an epidermal growth factor receptor/HER2 inhibitor, was associated with regressions of CNS lesions in a small phase 2 trial. The current study was done to further evaluate the CNS activity of lapatinib. The study was later amended to allow patients who progressed on lapatinib the option of receiving lapatinib plus capecitabine.

EXPERIMENTAL DESIGN

Eligible patients had HER2+ breast cancer, progressive brain metastases, prior trastuzumab, and cranial radiotherapy. The primary end point was CNS objective response, defined as >or=50% volumetric reduction of CNS lesion(s) in the absence of increasing steroid use, progressive neurologic signs and symptoms, or progressive extra-CNS disease.

RESULTS

Two-hundred and forty-two patients entered the study. CNS objective responses to lapatinib were observed in 6% of patients. In an exploratory analysis, 21% of patients experienced a >or=20% volumetric reduction in their CNS lesions. An association was observed between volumetric reduction and improvement in progression-free survival and neurologic signs and symptoms. Of the 50 evaluable patients who entered the lapatinib plus capecitabine extension, 20% experienced a CNS objective response and 40% experienced a >or=20% volumetric reduction in their CNS lesions.

CONCLUSIONS

This study confirms the modest CNS antitumor activity of lapatinib. Additional responses were observed with the combination of lapatinib and capecitabine. Further studies of lapatinib-based regimens for CNS metastases from HER2+ breast cancer are warranted.

Evaluation of lapatinib and topotecan combination therapy: tissue culture, murine xenograft, and phase I clinical trial data

PURPOSE

Topotecan resistance can result from drug efflux by P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) as well as survival signals initiated by epidermal growth factor receptor family members. The present studies were done to determine the effect of combining topotecan and the dual epidermal growth factor receptor/HER2 inhibitor lapatinib in tissue culture, a murine xenograft model, and a phase I clinical trial.

EXPERIMENTAL DESIGN

The effects of lapatinib on topotecan accumulation and cytotoxicity in vitro were examined in paired cell lines lacking or expressing Pgp or BCRP. Antiproliferative effects of the combination were assessed in mice bearing HER2+ BT474 breast cancer xenografts. Based on tolerability in this preclinical model, 37 patients with advanced-stage cancers received escalating doses of lapatinib and topotecan in a phase I trial.

RESULTS

Lapatinib increased topotecan accumulation in BCRP- or Pgp-expressing cells in vitro, and the combination showed enhanced efficacy in HER2+ BT474 xenografts. In the phase I study, nausea, vomiting, diarrhea, and fatigue were dose limiting. The maximum tolerated doses were 1,250 mg/d lapatinib by mouth for 21 or 28 days with 3.2 mg/m2 topotecan i.v. on days 1, 8, and 15 of 28-day cycles. Pharmacokinetic analyses showed that combined drug administration resulted in decreased topotecan clearance consistent with transporter-mediated interactions. Seventeen (46%) patients had disease stabilization.

CONCLUSIONS

The lapatinib/topotecan combination is well tolerated and warrants further study.

Single-agent lapatinib for HER2-overexpressing advanced or metastatic breast cancer that progressed on first- or second-line trastuzumab-containing regimens

BACKGROUND

This phase II study evaluated the efficacy and safety of lapatinib in patients with human epidermal growth factor receptor 2 (HER2)-positive advanced or metastatic breast cancer that progressed during prior trastuzumab therapy.

PATIENTS AND METHODS

Women with stage IIIB/IV HER2-overexpressing breast cancer were treated with single-agent lapatinib 1250 or 1500 mg once daily after protocol amendment. Tumor response according to RECIST was assessed every 8 weeks. HER2 expression was assessed in tumor tissue by immunohistochemistry and FISH.

RESULTS

Seventy-eight patients were enrolled in the study. Investigator and independent review response rates [complete response (CR) or partial response (PR)] were 7.7% and 5.1%, and clinical benefit rates (CR, PR, or stable disease for >or=24 weeks) were 14.1% and 9.0%, respectively. Median time to progression was 15.3 weeks by independent review, and median overall survival was 79 weeks. The most common treatment-related adverse events were rash (47%), diarrhea (46%), nausea (31%), and fatigue (18%).

CONCLUSIONS

Single-agent lapatinib has clinical activity with manageable toxic effects in HER2-overexpressing breast cancer that progressed on trastuzumab-containing therapy. Studies of lapatinib-based combination regimens with chemotherapy and other targeted therapies in metastatic and earlier stages of breast cancer are warranted.

Effect of lapatinib on the outgrowth of metastatic breast cancer cells to the brain

BACKGROUND

The brain is increasingly being recognized as a sanctuary site for metastatic tumor cells in women with HER2-overexpressing breast cancer who receive trastuzumab therapy. There are no approved or widely accepted treatments for brain metastases other than steroids, cranial radiotherapy, and surgical resection. We examined the efficacy of lapatinib, an inhibitor of the epidermal growth factor receptor (EGFR) and HER2 kinases, for preventing the outgrowth of breast cancer cells in the brain in a mouse xenograft model of brain metastasis.

METHODS

EGFR-overexpressing MDA-MB-231-BR (231-BR) brain-seeking breast cancer cells were transfected with an expression vector that contained or lacked the HER2 cDNA and used to examine the effect of lapatinib on the activation (ie, phosphorylation) of cell signaling proteins by immunoblotting, on cell growth by the tetrazolium salt 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, and on cell migration using a Boyden chamber assay. The outgrowth of large (ie, >50 microm(2)) and micrometastases was counted in brain sections from nude mice that had been injected into the left cardiac ventricle with 231-BR cells and, beginning 5 days later, treated by oral gavage with lapatinib or vehicle (n = 22-26 mice per treatment group). All statistical tests were two-sided.

RESULTS

In vitro, lapatinib inhibited the phosphorylation of EGFR, HER2, and downstream signaling proteins; cell proliferation; and migration in 231-BR cells (both with and without HER2). Among mice injected with 231-BR-vector cells, those treated with 100 mg lapatinib/kg body weight had 54% fewer large metastases 24 days after starting treatment than those treated with vehicle (mean number of large metastases per brain section: 1.56 vs 3.36, difference = 1.80, 95% confidence interval [CI] = 0.92 to 2.68, P < .001), whereas treatment with 30 mg lapatinib/kg body weight had no effect. Among mice injected with 231-BR-HER2 cells, those treated with either dose of lapatinib had 50%-53% fewer large metastases than those treated with vehicle (mean number of large metastases per brain section, 30 mg/kg vs vehicle: 3.21 vs 6.83, difference = 3.62, 95% CI = 2.30 to 4.94, P < .001; 100 mg/kg vs vehicle: 3.44 vs 6.83, difference = 3.39, 95% CI = 2.08 to 4.70, P < .001). Immunohistochemical analysis revealed reduced phosphorylation of HER2 in 231-BR-HER2 cell-derived brain metastases from mice treated with the higher dose of lapatinib compared with 231-BR-HER2 cell-derived brain metastases from vehicle-treated mice (P < .001).

CONCLUSIONS

Lapatinib is the first HER2-directed drug to be validated in a preclinical model for activity against brain metastases of breast cancer.

Lapatinib plus capecitabine for HER2-positive advanced breast cancer

BACKGROUND

Lapatinib, a tyrosine kinase inhibitor of human epidermal growth factor receptor type 2 (HER2, also referred to as HER2/neu) and epidermal growth factor receptor (EGFR), is active in combination with capecitabine in women with HER2-positive metastatic breast cancer that has progressed after trastuzumab-based therapy. In this trial, we compared lapatinib plus capecitabine with capecitabine alone in such patients.

METHODS

Women with HER2-positive, locally advanced or metastatic breast cancer that had progressed after treatment with regimens that included an anthracycline, a taxane, and trastuzumab were randomly assigned to receive either combination therapy (lapatinib at a dose of 1250 mg per day continuously plus capecitabine at a dose of 2000 mg per square meter of body-surface area on days 1 through 14 of a 21-day cycle) or monotherapy (capecitabine alone at a dose of 2500 mg per square meter on days 1 through 14 of a 21-day cycle). The primary end point was time to progression, based on an evaluation by independent reviewers under blinded conditions.

RESULTS

The interim analysis of time to progression met specified criteria for early reporting on the basis of superiority in the combination-therapy group. The hazard ratio for the independently assessed time to progression was 0.49 (95% confidence interval, 0.34 to 0.71; P<0.001), with 49 events in the combination-therapy group and 72 events in the monotherapy group. The median time to progression was 8.4 months in the combination-therapy group as compared with 4.4 months in the monotherapy group. This improvement was achieved without an increase in serious toxic effects or symptomatic cardiac events.

CONCLUSIONS

Lapatinib plus capecitabine is superior to capecitabine alone in women with HER2-positive advanced breast cancer that has progressed after treatment with regimens that included an anthracycline, a taxane, and trastuzumab. (ClinicalTrials.gov number, NCT00078572 [ClinicalTrials.gov].).

Anastrazole and oral contraceptives: a novel treatment for endometriosis

OBJECTIVE

To establish the use of aromatase inhibitors as a therapeutic option for endometriosis.

DESIGN

Prospective open-label Food and Drug Administration phase 2 trial with Institutional Review Board approval.

SETTING

Outpatient tertiary care centers.

PATIENT(S)

Fifteen premenopausal patients with documented refractory endometriosis and chronic pelvic pain.

INTERVENTION(S)

After a 1-month washout of endometriosis hormone therapies, women took 1 mg anastrazole (Arimidex; AstraZeneca, Wilmington, DE) and one tablet of 20 microg ethinyl estradiol/0.1 mg levonorgestrel (Alesse; Wyeth, Madison, NJ) daily for 6 months.

MAIN OUTCOME MEASURE(S)

An analog pain scale recorded pelvic pain in daily diaries and surveys at baseline and after each treatment month. Side effects, blood counts, liver and renal function tests, cholesterol levels, and bone density were monitored.

RESULT(S)

Fourteen of 15 patients achieved significant pain reduction. Median pain scores decreased 55% after 6 months, while mean pain scores decreased 40%. Pain reduction comparing each treatment month to baseline achieved statistical significance. Average pain scores began dropping after only 1 treatment month and continued decreasing each additional month. No organ system experienced adverse effects. Estradiol levels were suppressed during treatment. Side effects were mild and improved over time.

CONCLUSION(S)

Fourteen of 15 patients with refractory endometriosis achieved significant pain relief using anastrazole and 20 microg ethinyl estradiol/0.1 mg levonorgestrel with minimal side effects. This treatment for endometriosis is a promising new modality that warrants further investigation.

Effect of aromatase inhibition on lipids and inflammatory markers of cardiovascular disease in elderly men with low testosterone levels

OBJECTIVE

Although androgen replacement has been shown to have beneficial effects in hypogonadal men, there is concern that androgens may deleteriously affect cardiovascular risk in elderly men.

DESIGN

Anastrozole is an oral aromatase inhibitor that normalizes serum testosterone levels and decreases oestradiol levels modestly in elderly men with mild hypogonadism. Thirty-seven elderly hypogonadal men were randomized to receive either anastrozole 1 mg daily (n = 12), anastrozole 1 mg twice weekly (n = 11), or daily placebo (n = 14) for 12 weeks in a double-blind fashion.

PATIENTS

Men aged 62-74 years with mild hypogonadism defined by testosterone levels less than 350 ng/dl.

MEASUREMENTS

Serum levels of fasting lipids, C-reactive protein (CRP), interleukin-6 (IL-6), intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and homeostatic model assessment (HOMA) scores were measured at 4-week intervals.

RESULTS

Treatment with anastrozole did not significantly affect fasting lipids, inflammatory markers (IL-6, CRP), adhesion molecules (ICAM-1, VCAM-1) or insulin sensitivity (HOMA). There was, however, a positive correlation between changes in serum triglycerides and changes in serum oestradiol levels (P = 0.04).

CONCLUSIONS

While short-term administration of anastrozole is an effective method of normalizing serum testosterone levels in elderly men with mild hypogonadism, it does not appear to adversely affect lipid profiles, inflammatory markers of cardiovascular risk or insulin resistance.

Safety and efficacy of anastrozole for the treatment of pubertal gynecomastia: a randomized, double-blind, placebo-controlled trial

Pubertal gynecomastia is thought to result from transient imbalances between estrogen and androgen concentrations. Anastrozole (ARIMIDEX), a potent and selective aromatase inhibitor, decreases estrogen and increases testosterone concentrations in pubertal boys. The safety and efficacy of anastrozole for the treatment of pubertal gynecomastia were evaluated. In a randomized, double-blind, placebo-controlled study of 80 boys, aged 11-18 yr, with pubertal gynecomastia that had not reduced over a 3-month interval, subjects received either anastrozole (1 mg) or placebo once daily for 6 months. A response was defined as a 50% or greater reduction in the calculated volume of both breasts combined using ultrasonography measurements. A comparison of response rates was performed using logistic regression analysis. Secondary end points included changes in serum hormone concentrations. The percentage of patients with a response was 38.5% for the anastrozole group and 31.4% for the placebo group (odds ratio, 1.513; 95% confidence interval, 0.496-4.844; P = 0.47). At 6 months, the median percent change in the testosterone/estradiol ratio was 166% for the anastrozole group and 39% for the placebo group. Anastrozole treatment was well tolerated. In patients with pubertal gynecomastia, no significant difference in the percentage of patients with a 50% or greater reduction in total breast volume, as calculated from ultrasonography measurements, was demonstrated between the anastrozole and placebo groups.

Effects of aromatase inhibition in elderly men with low or borderline-low serum testosterone levels

As men age, serum testosterone levels decrease, a factor that may contribute to some aspects of age-related physiological deterioration. Although androgen replacement has been shown to have beneficial effects in frankly hypogonadal men, its use in elderly men with borderline hypogonadism is controversial. Furthermore, current testosterone replacement methods have important limitations. We investigated the ability of the orally administered aromatase inhibitor, anastrozole, to increase endogenous testosterone production in 37 elderly men (aged 62-74 yr) with screening serum testosterone levels less than 350 ng/dl. Subjects were randomized in a double-blind fashion to the following 12-wk oral regimens: group 1: anastrozole 1 mg daily (n = 12); group 2: anastrozole 1 mg twice weekly (n = 11); and group 3: placebo daily (n = 14). Hormone levels, quality of life (MOS Short-Form Health Survey), sexual function (International Index of Erectile Function), benign prostate hyperplasia severity (American Urological Association Symptom Index Score), prostate-specific antigen, and measures of safety were compared among groups. Mean +/- SD bioavailable testosterone increased from 99 +/- 31 to 207 +/- 65 ng/dl in group 1 and from 115 +/- 37 to 178 +/- 55 ng/dl in group 2 (P < 0.001 vs. placebo for both groups and P = 0.054 group 1 vs. group 2). Total testosterone levels increased from 343 +/- 61 to 572 +/- 139 ng/dl in group 1 and from 397 +/- 106 to 520 +/- 91 ng/dl in group 2 (P < 0.001 vs. placebo for both groups and P = 0.012 group 1 vs. group 2). Serum estradiol levels decreased from 26 +/- 8 to 17 +/- 6 pg/ml in group 1 and from 27 +/- 8 to 17 +/- 5 pg/ml in group 2 (P < 0.001 vs. placebo for both groups and P = NS group 1 vs. group 2). Serum LH levels increased from 5.1 +/- 4.8 to 7.9 +/- 6.5 U/liter and from 4.1 +/- 1.6 to 7.2 +/- 2.8 U/liter in groups 1 and 2, respectively (P = 0.007 group 1 vs. placebo, P = 0.003 group 2 vs. placebo, and P = NS group 1 vs. group 2). Scores for hematocrit, MOS Short-Form Health Survey, International Index of Erectile Function, and American Urological Association Symptom Index Score did not change. Serum prostate-specific antigen levels increased in group 2 only (1.7 +/- 1.0 to 2.2 +/- 1.5 ng/ml, P = 0.031, compared with placebo). These data demonstrate that aromatase inhibition increases serum bioavailable and total testosterone levels to the youthful normal range in older men with mild hypogonadism. Serum estradiol levels decrease modestly but remain within the normal male range. The physiological consequences of these changes remain to be determined.

Tamoxifen treatment for precocious puberty in McCune-Albright syndrome: a multicenter trial

OBJECTIVE

We undertook a 1-year multicenter trial of tamoxifen treatment for precocious puberty in girls with McCune-Albright syndrome (MAS).

STUDY DESIGN

Girls < or =10 years with classic or atypical MAS were recruited. Pretreatment history was collected for 6 months. Patients received 20 mg tamoxifen daily. Diaries were used to record bleeding. Evaluations included physical examination, bone age, pelvic ultrasound, hormone levels, and safety assessments.

RESULTS

A total of 28 girls (2.9-10.9 years of age) were enrolled from 20 centers, of whom 25 completed 12 months of tamoxifen treatment. Compared with before the study, vaginal bleeding episodes decreased (3.42+/-3.36/year vs 1.17+/-1.41/year), growth velocity slowed (SDS 1.22+/-2.65 vs -0.59+/-3.06, P=.005), and rate of bone maturation decreased (1.21+/-0.78 vs 0.72+/-0.36, P=.02). Ovarian volumes were enlarged and asymmetric throughout the study, and uterine volumes were increased. No adverse events occurred.

CONCLUSIONS

Tamoxifen treatment of precocious puberty in MAS results in a reduction of vaginal bleeding and significant improvements in growth velocity and rate of skeletal maturation.

Intravenous corticotrophin vs. hydrocortisone in the treatment of hospitalized patients with Crohn's disease: a randomized double-blind study and follow-up

Adrenocorticotrophic hormone (ACTH) and corticosteroids have no maintenance values for inflammatory bowel disease but serve to reduce the severity of disease. The effectiveness of intravenous corticotrophin versus hydrocortisone in ulcerative colitis has been determined including whether previous steroid therapy influenced the better response to one rather than the other, but no such studies have ever been done in Crohn's disease. Eighty-eight patients hospitalized with moderate-to-severe Crohn's disease (Present-Korelitz [P-K] Index -3 to -2 and the International Organisation for the Study of Inflammatory Bowel Disease-Crohn's & Colitis Foundation of America [IOIBD-CCFA] Index, mean 14, range 5-23) were treated in a prospective, randomized, double-blind clinical trial to receive either continuous intravenous infusion of 120 U/day of ACTH (44 patients) or hydrocortisone 300 mg/day (44 patients). Patients were also subdivided into those who received oral steroids during the 30 days prior to intravenous therapy and those who had not. Response was followed on a daily basis and tabulated at 3, 5, and 10 days. Patients were followed from 1-3 years to determine the later status. After 10 days of intravenous therapy 36 of 44 patients (82%) who received ACTH and 41 of 44 patients (93%) who received hydrocortisone fully responded (P-K index +3 and IOIBD-CCFA Index mean of 3). At the end of the study, response to intravenous ACTH and hydrocortisone was not statistically different whether or not patients received oral steroids during the 30 days prior to admission, although the response to IV ACTH tended to be faster at 3 days in those who had received previous steroid therapy. Intravenous ACTH and hydrocortisone are equally effective in achieving therapeutic goals in patients with Crohn's disease who have not achieved results with oral medications. Moreover the response rate was high (mean 88%), serving to buy time for establishment of successful maintenance programs of treatment with oral 5-ASA and immunosuppressive drugs for 69% of patients at 1-3 years.

Intravenous corticotrophin vs. hydrocortisone in the treatment of hospitalized patients with Crohn's disease: a randomized double-blind study and follow-up

Adrenocorticotrophic hormone (ACTH) and corticosteroids have no maintenance values for inflammatory bowel disease but serve to reduce the severity of disease. The effectiveness of intravenous corticotrophin versus hydrocortisone in ulcerative colitis has been determined including whether previous steroid therapy influenced the better response to one rather than the other, but no such studies have ever been done in Crohn's disease. Eighty-eight patients hospitalized with moderate-to-severe Crohn's disease (Present-Korelitz [P-K] Index -3 to -2 and the International Organisation for the Study of Inflammatory Bowel Disease-Crohn's & Colitis Foundation of America [IOIBD-CCFA] Index, mean 14, range 5-23) were treated in a prospective, randomized, double-blind clinical trial to receive either continuous intravenous infusion of 120 U/day of ACTH (44 patients) or hydrocortisone 300 mg/day (44 patients). Patients were also subdivided into those who received oral steroids during the 30 days prior to intravenous therapy and those who had not. Response was followed on a daily basis and tabulated at 3, 5, and 10 days. Patients were followed from 1-3 years to determine the later status. After 10 days of intravenous therapy 36 of 44 patients (82%) who received ACTH and 41 of 44 patients (93%) who received hydrocortisone fully responded (P-K index +3 and IOIBD-CCFA Index mean of 3). At the end of the study, response to intravenous ACTH and hydrocortisone was not statistically different whether or not patients received oral steroids during the 30 days prior to admission, although the response to IV ACTH tended to be faster at 3 days in those who had received previous steroid therapy. Intravenous ACTH and hydrocortisone are equally effective in achieving therapeutic goals in patients with Crohn's disease who have not achieved results with oral medications. Moreover the response rate was high (mean 88%), serving to buy time for establishment of successful maintenance programs of treatment with oral 5-ASA and immunosuppressive drugs for 69% of patients at 1-3 years.

Developmental expression of the vav protooncogene

We have examined the expression of the vav protooncogene during mouse embryogenesis using RNase protection assays, in situ hybridization, and immunocytochemical analysis. vav gene transcripts were first detected in E11.5 embryos in the blood-forming islands and megakaryocytes of the fetal liver. During diversification of hematopoietic activity in the embryo, vav gene expression became down-regulated in the liver and activated in thymus and spleen. In newborn animals, vav expression was also confined to hematopoietic tissues, with the exception of the ameloblastic cell layer at the latest stages of tooth morphogenesis. In the adult, vav transcripts were found in spleen, thymus, lymph nodes, and bone marrow, but not in liver. In spleen, vav transcripts were concentrated in the white pulp areas, whereas in the red pulp, the vav transcripts appeared to be primarily localized in the megakaryocytes. In thymus, vav expression was found to be more abundant in the cortical areas than in the medulla. In agreement with these observations, purified thymic lymphocytes showed heterogeneous immunoreactivity against the Vav protein, whereas splenic lymphocytes and bone marrow-derived cells displayed rather uniform levels of expression. These observations suggest that the vav protooncogene plays an important role in the signal transduction pathways that regulate the development and maintenance of the hematopoietic system.