Leuprorelin

Abstract: Spinal and bulbar muscular atrophy (SBMA) is an adult-onset motor neuron disease that affects males. It is caused by the expansion of a polyglutamine (polyQ) tract in androgen receptors. Female carriers are usually asymptomatic. No specific treatment has been established. Our transgenic mouse model carrying a full-length human androgen receptor with expanded polyQ has considerable gender-related motor impairment. This phenotype was abrogated by castration, which prevented nuclear translocation of mutant androgen receptors. We examined the effect of androgen-blockade drugs on our mouse model. Leuprorelin, a lutenizing hormone-releasing hormone (LHRH) agonist that reduces testosterone release from the testis, rescued motor dysfunction and nuclear accumulation of mutant androgen receptors in male transgenic mice. Moreover, leuprorelin treatment reversed the behavioral and histopathological phenotypes that were once caused by transient increases in serum testosterone. Flutamide, an androgen antagonist promoting nuclear translocation of androgen receptors, yielded no therapeutic effect. Leuprorelin thus seems to be a promising candidate for the treatment of SBMA.

Abstract: Purpose Gonadotropin-releasing hormone agonists decrease bone mineral density, lean mass, and muscle size and increase fat mass in men with prostate cancer. Less is known about the effects of bicalutamide monotherapy on bone mineral density and body composition. Patients and methods In a 12-month, open-label study, we randomly assigned 52 men with prostate cancer and no bone metastases to receive either leuprolide or bicalutamide (150 mg by mouth daily). Bone mineral density and body composition were measured by dual energy x-ray absorptiometry and quantitative computed tomography. Results Mean (+/- standard error) bone mineral density of the posterior-anterior lumbar spine decreased by 2.5% +/- 0.5% in the leuprolide group and increased by 2.5 +/- 0.5 in the bicalutamide group from baseline to 12 months (P Conclusion In men with prostate cancer, bicalutamide monotherapy increases bone mineral density, lessens fat accumulation, and has fewer bothersome side effects than treatment with a gonadotropin-releasing hormone agonist.

Abstract: Summary Background Spinal and bulbar muscular atrophy is a hereditary motor neuron disease caused by the expansion of a polyglutamine tract in the androgen receptor. At present there are no treatments for spinal and bulbar muscular atrophy, although leuprorelin suppressed the accumulation of pathogenic androgen receptors in a phase 2 trial. We aimed to assess the efficacy and safety of leuprorelin for spinal and bulbar muscular atrophy. Methods The Japan SBMA Interventional Trial for TAP-144-SR (JASMITT) was a 48-week, randomised, double-blind, placebo-controlled trial done at 14 hospitals between August, 2006, and March, 2008. Patients with spinal and bulbar muscular atrophy were randomly assigned (1:1) by minimisation to subcutaneous 11·25 mg leuprorelin or identical placebo every 12 weeks. Patients and investigators were masked to treatment allocation. The primary endpoint was pharyngeal barium residue, which indicates incomplete bolus clearance, measured at week 48 by videofluorography. All patients who were randomly assigned and who were assessed with videofluorography at least once were included in the analyses. This study is registered with the JMACCT clinical trials registry, number JMA-IIA00009, and the UMIN clinical trials registry, number UMIN000000465. Findings 204 patients were randomly assigned and 199 started treatment: 100 with leuprorelin and 99 with placebo. At week 48, the pharyngeal barium residue after initial swallowing had changed by −5·1% (SD 21·0) in the leuprorelin group and by 0·2% (18·2) in the placebo group (difference between groups −5·3%; 95% CI −10·8 to 0·3; p=0·063). The mean difference in pharyngeal barium residue after piecemeal deglutition at week 48 was −3·2% (−6·4 to 0·0; p=0·049), but there was no significant difference between the groups after covariate adjustment for the baseline data (−4·1 to 1·6; p=0·392). In a predefined subgroup analysis, leuprorelin treatment was associated with a greater reduction in barium residue after initial swallowing than was placebo in patients with a disease duration less than 10 years (difference between groups −9·8, −17·1 to −2·5; p=0·009). There were no significant differences in the number of drug-related adverse events between groups (57 of 100 in the leuprorelin group and 54 of 99 in the placebo group; p=0·727). Interpretation 48 weeks of treatment with leuprorelin did not show significant effects on swallowing function in patients with spinal and bulbar muscular atrophy, although it was well tolerated. Disease duration might influence the efficacy of leuprorelin and thus further clinical trials with sensitive outcome measures should be done in subpopulations of patients. Funding Large Scale Clinical Trial Network Project, Japan and Takeda Pharmaceuticals.