Relationship Between Baseline and Early Changes in C-Reactive Protein and Interleukin-6 Levels and Clinical Response to Tocilizumab in Rheumatoid Arthritis.

OBJECTIVE: To clarify the relevance of measuring interleukin-6 (IL-6) and C-reactive protein (CRP) levels in order to predict clinical response to tocilizumab (TCZ) in rheumatoid arthritis patients. METHODS: In a pooled, post hoc analysis of 5 pivotal trials of TCZ, we examined the distributions of baseline serum concentrations of IL-6 and CRP, stratified by randomized treatment group, and week 24 Disease Activity Score in 28 joints (DAS28) status (DAS28 <2.6 versus DAS28 ≥2.6). Relationships between early biomarker changes and later changes in DAS28 scores were evaluated using Spearman's correlations and scatterplots. Finally, percentage changes from baseline in IL-6 and CRP levels were evaluated. RESULTS: Distributions of baseline IL-6 and CRP levels were similar for patients who achieved DAS28 scores <2.6 within 6 months of TCZ initiation and those who did not. Correlations between early changes in these 2 biomarkers and change in DAS28 scores were low (rho < 0.3 for all). Mean percentage increases from baseline in IL-6 concentrations were observed in all treatment groups (highest in the 8 mg/kg dose group); mean percentage decreases in CRP concentrations were greater at week 2 and at all visits for the 8 mg/kg dose group. CONCLUSION: Baseline serum concentrations of IL-6 and CRP may not be predictive of clinical outcomes after TCZ treatment. Data demonstrate the efficacy of TCZ in patients across a broad range of baseline serum IL-6 and CRP concentrations. Similarly, changes in these biomarkers after TCZ dosing are expected and may or may not correspond to changes in other clinical signs and symptoms. These results complement previous reports describing the complex interactions among biomarker changes, other therapeutic mechanisms of action, and clinical outcomes.

Effect of concomitant administration of trospium chloride extended release on the steady-state pharmacokinetics of metformin in healthy adults.

BACKGROUND: Overactive bladder (OAB) is often associated with a number of co-morbid medical conditions, including diabetes mellitus. This may necessitate several concomitant treatments, thus creating the potential for drug-drug interactions (DDIs). Trospium is renally eliminated, not metabolized via cytochrome P450; therefore, cytochrome P450 DDIs are unlikely. However, coadministration with another renally eliminated drug (e.g., metformin) may theoretically result in a DDI. OBJECTIVE: The objective of this study was to evaluate the pharmacokinetics (plasma and urine) and safety/tolerability of the coadministration of trospium chloride extended release (XR) and metformin under steady-state conditions in healthy male and female subjects. METHODS: In a single-centre, randomized, open-label, two-group, two-period study in healthy males and females aged 18-45 years, 44 subjects received oral metformin 500 mg twice daily for 3.5 days during one period, and oral trospium chloride XR 60 mg once daily for 10 days, followed by trospium chloride XR 60 mg once daily for 4 days plus metformin 500 mg twice daily for 3.5 days during the other period. The two periods occurred in a crossover fashion, separated by a 3-day washout period. RESULTS: Trospium chloride XR coadministration did not alter metformin steady-state pharmacokinetics. Metformin coadministration reduced trospium steady-state maximum plasma concentration (by 34 %) and area under the concentration-time curve from 0-24 hours (by 29 %). Neither drug's renal clearance was affected. No safety/tolerability issues of concern were observed with coadministration. CONCLUSION: No dosage adjustment is necessary for metformin when coadministered with trospium chloride XR.

Translational research: current status, challenges and future strategies.

Advances in translational research are expected to mitigate the recent drought in new drug development. Despite significant progress recently made in biological sciences, the results are decidedly mixed with significant breakthrough in some disease areas while extensive work remains to be completed in other areas. This review article provides a general survey of the current landscape of translational research so as to identify progress and areas of needs and the associated strategy. While significant advances in the development of translational tools have been made in all fronts, the availability of predictive preclinical models remains critical for the success of translational research. This is directly correlated with the success of translational research as illustrated by the recent approval of targeted drug therapies. By the same logic, unexpected side effects can also be explained by laboratory findings, thus completing the translational cycle. Because of this reason, further collaboration between preclinical and clinical scientists is essential. Non-scientific issues have important influence on the future of this endeavor cannot be underestimated either. Nonetheless, with definitive commitment of private industry and public resources, the future of translational research is promising.

Disposition and biotransformation of the acetylenic retinoid tazarotene in humans.

Oral tazarotene, an acetylenic retinoid, is in clinical development for the treatment of psoriasis. The disposition and biotransformation of tazarotene were investigated in six healthy male volunteers, following a single oral administration of a 6 mg (100 microCi) dose of [14C]tazarotene, in a gelatin capsule. Blood levels of radioactivity peaked 2 h postdose and then rapidly declined. Total recovery of radioactivity was 89.2+/-8.0% of the administered dose, with 26.1+/-4.2% in urine and 63.0+/-7.0% in feces, within 7 days of dosing. Only tazarotenic acid, the principle active metabolite formed via esterase hydrolysis of tazarotene, was detected in blood. One major urinary oxidative metabolite, tazarotenic acid sulfoxide, accounted for 19.2+/-3.0% of the dose. The majority of radioactivity recovered in the feces was attributed to tazarotenic acid representing 46.9+/-9.9% of the dose and only 5.82+/-3.84% of dose was excreted as unchanged tazarotene. Thus following oral administration, tazarotene was rapidly absorbed and underwent extensive hydrolysis to tazarotenic acid, the major circulating species in the blood that was then excreted unchanged in feces. A smaller fraction of tazarotenic acid was further metabolized to an inactive sulfoxide that was excreted in the urine.

Comparison of electron beam computed tomography and technetium stress testing in differentiating cause of dilated versus ischemic cardiomyopathy.

OBJECTIVE: The current reference standard for differentiating between nonischemic versus ischemic cardiomyopathy (CM) is angiography. The diagnostic accuracy of nuclear stress testing and electron beam tomography (EBT) was evaluated to differentiate between nonischemic and ischemic CM, using coronary angiography as the reference standard. METHODS: A total of 56 patients who underwent technetium stress testing and coronary angiography for the evaluation of CM were enrolled. Patients then underwent EBT coronary scanning for coronary calcification (CC). RESULTS: Of the 56 patients, 34 (61%) had angiographically significant disease. Using the criteria of ischemia (reversible defect) or infarct (fixed defect) to define a patient with ischemic CM, nuclear stress testing had a sensitivity of 97% (33 of 34 patients) but a specificity of only 18% (4 of 22 patients). Using the criteria of reversible ischemia only, the specificity of nuclear stress testing improved to 50% (P < 0.001); however, the sensitivity decreased to 56%. An EBT score >0 had a sensitivity of 97% (33 of 34 patients) and a specificity of 68% (15 of 22 patients) for defining ischemia. Overall diagnostic accuracy was significantly higher with EBT as compared with nuclear stress testing in this study of patients with reduced ejection fractions (84% vs. 64%; P = 0.009). CONCLUSION: Given the high sensitivity of nuclear testing and EBT, these tests may prove to be an effective screen before angiography in patients with congestive heart failure of unclear cause.

Diabetes and progression of coronary calcium under the influence of statin therapy.

BACKGROUND: Coronary artery calcium (CAC) is a sensitive marker for the detection of coronary heart disease (CHD). Coronary artery calcification can be accurately quantified using electron beam tomography (EBT). We sought to evaluate the progression of atherosclerosis in asymptomatic persons with type 2 diabetes and measure the influence of statin therapy on CAC progression. METHODS: We evaluated 163 asymptomatic patients with type 2 diabetes (120 men, 43 women). Patients were physician referred and underwent 2 consecutive EBT scans at least 1 year apart. Demographic data, risk factors for CHD, and medication use were collected. Patients with symptoms or known CHD were excluded. RESULTS: The mean age was 65 +/- 10 years. The mean CAC score at baseline was 651 +/- 414. Only 9 (6%) of 163 of participants had scores of 0 at baseline. The time between scans averaged 27 +/- 15 months. Patients not treated with statins demonstrated a median annual increase in CAC progression of 20% (4%-44%), whereas statin-treated patients demonstrated increase of 10% (4%-25%) (P = .0001). Hemoglobin A 1c was weakly associated with CAC progression. CONCLUSIONS: Asymptomatic diabetic patients show a high prevalence of atherosclerosis based on high frequency of coronary calcification. Statin therapy induced a 50% reduction in the rate of CAC progression. As rapid CAC progression has been associated with coronary events, EBT may serve as a noninvasive method for following atherosclerosis and response to therapy.

Tazarotene does not affect the pharmacokinetics and efficacy of a norethindrone/ethinylestradiol oral contraceptive.

OBJECTIVE: To determine the pharmacokinetic and pharmacodynamic interaction between oral tazarotene and an oral contraceptive containing norethindrone 1mg and ethinylestradiol 0.035 mg (Ortho-Novum 1/35). DESIGN: Two separate open-label, parallel-group, single-centre, pharmacokinetic and pharmacodynamic interaction studies. PARTICIPANTS AND METHODS: Twenty-seven healthy women (age 20-55 years) completed Study I, with a duration of 64 days during three consecutive menstrual cycles. Ortho-Novum 1/35 was taken once daily from study day 0 (first cycle day 1) to day 61 (third cycle day 6), and oral tazarotene 1.1 mg was coadministered daily from study day 34 (second cycle day 7) to day 61. Twenty-nine healthy women (age 20-44 years) completed Study II, with a duration of 75 days during three consecutive menstrual cycles. Ortho-Novum 1/35 was taken once daily from study day 0 (first cycle day 1) to day 74 (third cycle day 19), and oral tazarotene 6 mg was coadministered daily from study day 48 (second cycle day 21) to day 74. In both studies, the pharmacokinetics of tazarotenic acid on study day 61 (third cycle day 6) were evaluated from plasma tazarotenic acid concentrations. Pharmacokinetic parameters of plasma norethindrone and ethinylestradiol were compared before and after tazarotene administration (cycle day 6 of the second and third cycles, respectively). Serum luteinising hormone (LH) and follicle-stimulating hormone (FSH) concentrations were compared before and after tazarotene administration (cycle days 2, 4 and 6 of the second and third cycles, respectively). In Study II, serum progesterone concentrations were also determined on cycle days 18 and 20 of the second and third cycles. Tazarotenic acid was determined by liquid chromatography-tandem mass spectrometry. Ethinylestradiol and norethindrone were determined by gas chromatography-mass spectrometry. LH and FSH were assayed by microparticle enzyme immunoassay in Study I and by double-antibody radioimmunoassay in Study II. Progesterone was determined by solid-phase radioimmunoassay. RESULTS: In Study I (tazarotene 1.1 mg), the area under the plasma concentration-time curve from zero to 24 hours (AUC24) and the peak concentration in plasma (Cmax) for tazarotenic acid were 121 +/- 27 microg. h/L and 28.9 +/- 9.4 microg/L (mean +/- SD), respectively. In Study II (tazarotene 6 mg), AUC24 and Cmax for tazarotenic acid were 379 +/- 78 microg. h/L and 111 +/- 37 microg/L (mean +/- SD), respectively. In both studies, for both norethindrone and ethinylestradiol, the 90% CIs of AUC24 and Cmax on cycle day 6 before and after tazarotene administration were within the 80-125% boundary. In Study I, the 90% CIs of serum FSH and LH concentrations on cycle day 4 were within the 80-125% boundary. FSH and LH concentrations on cycle day 6 were marginally/partially outside the 80-125% boundary as a result of high variability. However, the mean FSH and LH serum concentrations on cycle day 6 of the third cycle were lower than those of the second cycle. In Study II, the 90% CIs of serum FSH, LH and progesterone concentrations were all within the 80-125% boundary, except for LH on cycle day 2. LH concentrations on cycle day 2 were marginally/partially outside the 80-125% boundary as a result of high variability. However, the mean serum LH concentration on cycle day 2 of the third cycle was lower than that of the second cycle. CONCLUSIONS: Oral tazarotene up to 6 mg once daily does not affect the pharmacokinetics and efficacy of Ortho-Novum 1/35.

Pharmacokinetics of tazarotene cream 0.1% after a single dose and after repeat topical applications at clinical or exaggerated application rates in patients with acne vulgaris or photodamaged skin.

OBJECTIVE: To evaluate the safety and pharmacokinetics of tazarotene cream 0.1% under standard (face only) or exaggerated (15% body surface area, including the face) application conditions after a single dose and after repeat topical applications once daily to patients with acne vulgaris or photodamaged skin. METHODS: Two separate, randomised, single-centre, nonblinded, parallel-group pharmacokinetic studies were conducted. In one study, tazarotene cream 0.1% was applied either to the face of eight female patients with moderate acne or to 15% body surface area of ten female patients with severe acne. In the other study, tazarotene cream 0.1% was applied either to the face (six females, two males) or to 15% body surface area (8 females, 8 males) of patients with photodamaged skin. In both studies, tazarotene cream 0.1% was applied once daily (except on days 1 and 2) for 30 days. Blood was drawn for measurement of plasma concentrations of tazarotenic acid at defined time intervals after application of the cream. Plasma tazarotenic acid concentrations were determined by a validated gas chromatography-tandem mass spectrometry method with a lower limit of quantification of 0.005 microg/L. RESULTS: At exaggerated application rates in patients with acne vulgaris, the maximum average peak concentration (C(max)) and 24-hour area under the concentration-time curve (AUC) values of tazarotenic acid were (mean +/- SD) 1.20 +/- 0.41 microg/L (n = 10) and 17.0 +/- 6.1 microg. h/L (n = 10), respectively, and occurred on day 15. The single highest C(max) was 1.91 microg/L. At standard application rates in patients with acne vulgaris, the maximum average C(max) and AUC values of tazarotenic acid were 0.10 +/- 0.06 microg/L (n = 8) and 1.54 +/- 1.01 microg. h/L (n = 8), respectively, and occurred on day 15. At exaggerated application rates in patients with photodamaged skin, the maximum average C(max) and AUC values of tazarotenic acid were (mean +/- SD) 1.75 +/- 0.53 microg/L (n = 16) and 23.8 +/- 7.0 microg. h/L (n = 16), respectively, and occurred on day 22. The single highest C(max) was 3.43 microg/L on day 29. At standard application rates in patients with photodamaged skin, the maximum average C(max) and AUC values of tazarotenic acid were 0.236 +/- 0.255 microg/L (n = 8) and 2.44 +/- 1.38 microg. h/L (n = 8), respectively, and occurred on day 15. Gender had no influence on the systemic exposure of tazarotenic acid. The most common treatment-related adverse events were signs and symptoms of local irritation, of mild or moderate severity. CONCLUSIONS: The pharmacokinetics of tazarotene cream 0.1% in patients with acne vulgaris or photodamaged skin are similar. The maximum average plasma concentrations of tazarotenic acid after topical application of tazarotene cream 0.1% to the face were less than 0.25 microg/L. The maximum average plasma concentrations of tazarotenic acid following application to an exaggerated body surface area (15%) were less than 1.8 microg/L.