Jennifer Rotonda

A combinatorial approach for determining protease specificities: application to interleukin-1beta converting enzyme (ICE).

BACKGROUND Interleukin-1beta converting enzyme (ICE/caspase-1) is the protease responsible for interleukin-1beta (IL-1beta) production in monocytes. It was the first member of a new cysteine protease family to be identified. Members of this family have functions in both inflammation and apoptosis. RESULTS A novel method for identifying protease specificity, employing a positional-scanning substrate library, was used to determine the amino-acid preferences of ICE. Using this method, the complete specificity of a protease can be mapped in the time required to perform one assay. The results indicate that the optimal tetrapeptide recognition sequence for ICE is WEHD, not YVAD, as previously believed, and this led to the synthesis of an unusually potent aldehyde inhibitor, Ac-WEHD-CHO (Ki = 56 pM). The structural basis for this potent inhibition was determined by X-ray crystallography. CONCLUSIONS The results presented in this study establish a positional-scanning library as a powerful tool for rapidly and accurately assessing protease specificity. The preferred sequence for ICE (WEHD) differs significantly from that found in human pro-interleukin-1beta (YVHD), which suggests that this protease may have additional endogenous substrates, consistent with evidence linking it to apoptosis and IL-1alpha production.

The three-dimensional structure of human granzyme B compared to caspase-3, key mediators of cell death with cleavage specificity for aspartic acid in P1

BACKGROUND Granzyme B, one of the most abundant granzymes in cytotoxic T-lymphocyte (CTL) granules, and members of the caspase (cysteine aspartyl proteinases) family have a unique cleavage specificity for aspartic acid in P1 and play critical roles in the biochemical events that culminate in cell death. RESULTS We have determined the three-dimensional structure of the complex of the human granzyme B with a potent tetrapeptide aldehyde inhibitor. The Asp-specific S1 subsite of human granzyme B is significantly larger and less charged than the corresponding Asp-specific site in the apoptosis-promoting caspases, and also larger than the corresponding subsite in rat granzyme B. CONCLUSIONS The above differences account for the variation in substrate specificity among granzyme B, other serine proteases and the caspases, and enable the design of specific inhibitors that can probe the physiological functions of these proteins and the disease states with which they are associated.

Long-Term Treatment With Finasteride Results in a Clinically Significant Reduction in Total Prostate Volume Compared to Placebo Over the Full Range of Baseline Prostate Sizes in Men Enrolled in the MTOPS Trial

PURPOSE In the present analysis we examined data from the MTOPS (Medical Therapy of Prostatic Symptoms) trial to determine the effect of long-term finasteride treatment, either alone or in combination with doxazosin, on total prostate volume across the full range of baseline total prostate volume values in men enrolled in this study. MATERIALS AND METHODS In this trial a total of 3,047 patients with lower urinary tract symptoms were randomized to placebo, doxazosin (4 to 8 mg), finasteride (5 mg) or the combination of doxazosin and finasteride (average length of treatment 4.5 years). Total prostate volume was measured by transrectal ultrasound in all patients at baseline, yearly and at study end or at termination of participation. RESULTS Long-term treatment with finasteride led to a consistent reduction of approximately 25% in total prostate volume compared to placebo in men with a relatively small prostate (less than 25 to 30 ml), as well as in those with a moderate size (30 to less than 40 ml) or enlarged prostate (40 ml or greater) at baseline. CONCLUSIONS In this MTOPS data analysis long-term (more than 4 years) treatment with finasteride, either alone or in combination with doxazosin, led to a consistent, clinically significant reduction in total prostate volume compared to placebo in patients with lower urinary tract symptoms and benign prostatic hyperplasia whose baseline prostate size ranged from relatively small (less than 25 to 30 ml) to enlarged (40 ml or greater).

Long-term treatment with finasteride 1 mg decreases the likelihood of developing further visible hair loss in men with androgenetic alopecia (male pattern hair loss)

There are no reports on the effects of pharmacologic treatment on the likelihood of developing further visible hair loss in men with androgenetic alopecia (AGA). Our objectives were to examine whether finasteride 1 mg treatment decreases the likelihood of developing further visible hair loss in men with AGA. We conducted an analysis of global photographic assessment data from two Phase III trials in which 1553 men with AGA received finasteride 1 mg/day or placebo for up to 5 years. Finasteride 1 mg treatment led to a 93% decrease relative to placebo in the 5-year likelihood of developing further visible hair loss (95% CI: 89-97%; p < 0.001). We conclude that, in men with AGA, treatment with finasteride 1 mg/day over 5 years led to a marked and sustained decrease in the likelihood of developing further visible hair loss.

Global photographic assessment of men aged 18 to 60 years with male pattern hair loss receiving finasteride 1 mg or placebo

BACKGROUND Finasteride (1 mg) has been shown to increase vertex hair growth in men aged 18 to 60 years with male pattern hair loss and to increase frontal scalp hair growth in subjects aged 18 to 41 years. OBJECTIVE A secondary efficacy analysis was conducted to determine effects of finasteride (1 mg) on scalp hair growth in the 4 distinct scalp regions affected by male pattern hair loss. METHODS Multicenter, double-blind studies randomized patients with vertex hair loss (men aged 18-41 and 41-60 years) to finasteride (1 mg/d) or placebo. Efficacy was evaluated by review of standardized clinical photographs (global photographic assessment) of the vertex, anterior/mid scalp regions, and frontal and temporal hairlines over 24 months relative to baseline. RESULTS At 24 months, treatment with finasteride resulted in statistically significant (P ≤ .05) hair growth versus placebo in all scalp regions. There was also a significant decrease in hair loss in the younger men treated with finasteride in all areas, but only in the vertex and anterior/mid scalp regions in the older men. A slightly higher incidence of drug-related sexual adverse experiences was reported in the finasteride group than in the placebo group, irrespective of age. LIMITATIONS These studies enrolled men with vertex pattern hair loss; therefore, the findings may not be extrapolated to men with predominantly anterior/mid scalp, frontal, or temporal hair loss. CONCLUSION Based on global photographic assessment, finasteride (1 mg) is able to increase hair growth in all areas of the scalp affected by male pattern hair loss.

Consistency of lipid-altering effects of ezetimibe/simvastatin across gender, race, age, baseline low density lipoprotein cholesterol levels, and coronary heart disease status: results of a pooled retrospective analysis.

ABSTRACT Background: The combination tablet containing ezetimibe and simvastatin (EZE/SIMVA), inhibits both the intestinal absorption and endogenous production of cholesterol, providing significantly greater low-density lipoprotein cholesterol (LDL-C) lowering than EZE or SIMVA alone. The purpose of this pooled analysis was to evaluate the consistency of efficacy (i.e., between-treatment difference) of EZE/SIMVA versus SIMVA within several selected subgroups of patients with primary hypercholesterolemia. Methods: For the present analysis, data were pooled from three similarly designed, 12‐week, randomized, double-blind, placebo-controlled factorial studies consisting of 3083 patients with primary hypercholesterolemia ( n = 311 in placebo group; n = 302 in EZE group; n = 1234 in pooled SIMVA group; n = 1236 in pooled EZE/SIMVA group). In these clinical studies, primary hypercholesterolemia was defined as an LDL‐C value between 145 and 250 mg/dL inclusive and a triglyceride (TG) level of less than 350 mg/dL. The results for the pooled SIMVA and pooled EZE/SIMVA groups were used for the present analyses. The pooled analyses focused on the consistency of the between-treatment differences (i.e., incremental effect) for EZE/SIMVA (pooled across doses) versus SIMVA (pooled across doses) on various lipid and non-lipid parameters within different patient subgroups defined according to gender, race (Caucasian, Non-Caucasian), baseline age (< 65, ≥ 65 years), baseline LDL‐C (< 160, ≥ 160 mg/dL), and coronary heart disease (CHD) history. Tolerability was also examined for pooled EZE/SIMVA and pooled SIMVA within these selected subgroups. In a modified intention-to-treat analysis, an ANOVA model was used for testing the consistency of pooled treatment effects on lipid and non-lipid parameters within each selected subgroup. Results: For the entire cohort, baseline lipid profiles were similar for the patients in the pooled EZE/SIMVA group compared with those in the pooled SIMVA group. Treatment with EZE/SIMVA led to significant ( p < 0.001) incremental improvements in LDL‐C, non-high density lipoprotein cholesterol (non-HDL‐C), apolipoprotein B, TG and high sensitivity C‐reactive protein compared to SIMVA, across the entire cohort. These changes were consistent within each of the selected subgroups. Moreover, more patients attained LDL‐C goal levels < 100 mg/dL with EZE/SIMVA than with SIMVA in the entire cohort and this was consistent across all subgroups, except baseline LDL‐C. In this pooled retrospective analysis, treatment with EZE/SIMVA was generally well tolerated across subgroups, with a safety profile similar to SIMVA monotherapy. Although this pooled analysis was performed on a large cohort of patients with primary hypercholesterolemia, the results of this analysis were specific for this select patient population and generalizations to other populations should be applied with caution. Conclusion: The enhanced lipid-altering effects of EZE/SIMVA versus those of SIMVA observed in the entire cohort were consistent within all subgroups examined. EZE/SIMVA represents an effective and well-tolerated therapeutic option for the treatment of a wide range of patient subgroups with primary hypercholesterolemia.

Progression of hair loss in men with androgenetic alopecia (male pattern hair loss): long-term (5-year) controlled observational data in placebo-treated patients

Relatively little is known about the progression of androgenetic alopecia (AGA; male pattern hair loss) in untreated men. We evaluated the long-term (5-year) progression of AGA in men treated with placebo in a controlled clinical trial setting. We analyzed pooled data over 5 years from two replicate studies with finasteride 1 mg/day in men with predominantly vertex-pattern AGA. Each study consisted of an initial 1-year, randomized, double-blind, placebo-controlled base study and four consecutive, 1-year, double-blind, placebo-controlled extension studies. Change over time in scalp hair growth was evaluated by four predefined endpoints: scalp hair counts; assessment of standardized clinical photographs by an expert panel; investigator clinical assessment; and patient self-assessment. All four predefined endpoints demonstrated progressive scalp hair loss in men receiving placebo over the 5-year study period, with a loss of 239 hairs from baseline (26.3% decline in hair density) measured in the target area at 5 years (p < 0.001 vs. baseline). Similarly, visible progression of scalp hair loss was demonstrated by global photographic assessment, with 75% of placebo patients rated as worsened from baseline at 5 years. We found that scalp hair loss continued in a progressive manner over a 5-year period in placebo-treated men with AGA.

No Pharmacokinetic Drug–Drug Interaction Between Prasugrel and Vorapaxar Following Multiple-Dose Administration in Healthy Volunteers

Vorapaxar is a first‐in‐class antagonist of the protease‐activated receptor‐1, the primary thrombin receptor on human platelets, which mediates the downstream effects of thrombin in hemostasis and thrombosis. Prasugrel is a platelet inhibitor that acts as a P2Y12 receptor antagonist through an active metabolite, R‐138727. This study investigated the interaction of these 2 platelet antagonists when coadministered. This was a randomized, open‐label, multiple‐dose study in 54 healthy volunteers consisting of a fixed‐sequence crossover and a parallel group design. In sequence 1, 36 subjects received prasugrel 60 mg on day 1 and then prasugrel 10 mg once daily on days 2 to 7, followed by vorapaxar 40 mg and prasugrel 10 mg on day 8 and then vorapaxar 2.5 mg and prasugrel 10 mg orally once daily on days 9 to 28. In sequence 2, 18 subjects received vorapaxar 40 mg on day 1 and then vorapaxar 2.5 mg once daily on days 2 to 21. The geometric mean ratios (90% confidence intervals) for AUCτ and Cmax of coadministration/monotherapy for vorapaxar (0.93 ng·h/mL[0.85–1.02 ng·h/mL] and 0.95 ng/mL [0.86–1.05 ng/mL]) and R‐138727 (0.91 ng·h/mL [0.85– 0.99 ng·h/mL] and 1.02 ng/mL [0.89–1.17 ng/mL]) were within prespecified bounds, demonstrating the absence of a pharmacokinetic interaction between vorapaxar and prasugrel. There was no specific safety or tolerability risk associated with multiple‐dose coadministration of vorapaxar and prasugrel. In conclusion, in this study in healthy volunteers, there was no pharmacokinetic drug–drug interaction between vorapaxar and prasugrel. Multiple‐dose coadministration of the 2 drugs was generally well tolerated.