Effective Partnering in Conducting Benefit-Risk Patient Preference Studies: Perspectives From a Patient Advocacy Organization, a Pharmaceutical Company, and Academic Stated-Preference Researchers.

BACKGROUND: Formal incorporation of patients' perspectives is becoming increasingly important in medical product development and decision making. This article shares practical advice regarding how patient advocacy organizations, the pharmaceutical industry, and academic experts in stated-preference research can effectively partner on benefit-risk patient preference studies. METHODS: The authors partnered on a benefit-risk patient preference study related to the treatment of psoriasis. The authors from Duke Clinical Research Institute also share their experiences in collaborating with numerous other organizations in conducting benefit-risk patient preference studies. RESULTS: Upon initiation of the study partnership with appropriate experts, training is important to ensure all collaborators have a common understanding of the methodology, what objectives stated-preference methods can support, and expectations for the project. To the extent possible, partners should align on and document relevant clinical and logistical details prior to study implementation. During study implementation, partners should use good communication practices and document and maintain a record of any changes to the original plan. Presentation of the study results should be tailored to the particular audience, with the appropriate partner leading the presentation based on its format and audience. CONCLUSION: Partners from patient advocacy organizations, the pharmaceutical industry, and academia can effectively collaborate on benefit-risk patient preference studies with sufficient planning and ongoing communication. This article is a call for action for other organizations to engage in sharing of experiences regarding effective partnering in quantifying patient preferences in medical product development.

What is clearance worth? Patients' stated risk tolerance for psoriasis treatments.

PURPOSE: The purpose of this study was to provide quantitative evidence of patients' tolerance for therapeutic risks associated with psoriasis treatments that could offer psoriasis improvements beyond the PASI 75 benchmark. MATERIALS AND METHODS: We used a discrete-choice experiment in which respondents chose between competing psoriasis treatments characterized by benefits (i.e. reduced plaque severity, reduced plaque area), risks (i.e. 10-year risk of tuberculosis, 10-year risk of death from infection), and treatment regimen. We analyzed choice data using random-parameters logit models for psoriasis affecting the body, face, or hands. RESULTS: Of 927 eligible members of the National Psoriasis Foundation who completed the survey, 28% were unwilling to accept any greater risk of treatment-related infection mortality. Among the remaining 72%, respondents were willing to accept higher risks of infection-related mortality associated with treatment to completely remove plaques covering only 1% of the body, compared to reducing lesions from 10 to 1% of the affected area. This finding was more pronounced for lesions on the face. CONCLUSIONS: Most patients placed greater value on eliminating even very small plaques compared to avoiding treatment-related risks. The perceived importance of complete versus near-complete clearance was stronger than previously documented.

Implementing Benefit-Risk Assessment for the Periodic Benefit-Risk Evaluation Report.

BACKGROUND: In 2012, the International Conference on Harmonisation (ICH) E2C (R1) guideline for periodic safety update reporting (PSUR) for medicines was revised. Several new concepts that expanded the scope of the report were added, including a new section focused on benefits and an additional section focused on integrated benefit-risk (B-R) assessment. These changes are reflected in the new title of the report, namely, the Periodic Benefit-Risk Evaluation Report (PBRER). Recently, structured frameworks have been developed by the pharmaceutical industry and regulatory agencies to facilitate B-R analysis for medicines. METHODS: This manuscript provides suggestions for incorporating the elements of a structured B-R assessment into the PBRER and also includes practical approaches for implementing the ICH guidelines for the B-R analysis section. RESULTS: The main components of a B-R assessment for the PBRER include decision context; key benefits and key risks; strengths, limitations, and uncertainties of the evidence; risk management; and the overall B-R conclusions. CONCLUSIONS: A structured, systematic approach to defining a medicine's B-R profile will help ensure compliance with this ICH objective for the PBRER.

Patient Engagement at a Tipping Point-The Need for Cultural Change Across Patient, Sponsor, and Regulator Stakeholders: Insights From the DIA Conference, "Patient Engagement in Benefit Risk Assessment Throughout the Life Cycle of Medical Products".

Benefit-risk assessment is the foundation for decision making throughout the life cycle of medical products. Because patients are the beneficiaries of the efficacy of medical treatments and also bear their possible risks, their perspectives and judgments about value and the relative importance of benefits and risks should be at the heart of the medical decision-making process. Patient engagement is now at a tipping point; there have been a growing number of patient engagement initiatives over the past several years, but there remains the need for a common language, alignment on engagement approaches and best practices, and a shared vision regarding a desired future state. This article discusses insights gleaned from the DIA conference, "Patient Engagement in Benefit-Risk Assessment throughout the Life Cycle of Medical Products" (September 2015). It highlights the changes that will need to occur within the patient, medical-product sponsor, and regulatory cultures in order for patient engagement to become integrated into the medical-product development process and life cycle maintenance. Furthermore, it emphasizes that reaching the desired future state will require a conscious commitment from all stakeholders to work collaboratively to develop shared solutions and to map a common path forward.

Efficacy and safety of exenatide once weekly versus metformin, pioglitazone, and sitagliptin used as monotherapy in drug-naive patients with type 2 diabetes (DURATION-4): a 26-week double-blind study.

OBJECTIVE: To test the safety and efficacy of exenatide once weekly (EQW) compared with metformin (MET), pioglitazone (PIO), and sitagliptin (SITA) over 26 weeks, in suboptimally treated (diet and exercise) drug-naive patients with type 2 diabetes. RESEARCH DESIGN AND METHODS: Patients were randomized to subcutaneous (SC) EQW 2.0 mg + oral placebo (n = 248), MET 2,000 mg/day + SC placebo (n = 246), PIO 45 mg/day + SC placebo (n = 163), or SITA 100 mg/day + SC placebo (n = 163) for 26 weeks. MET and PIO therapies were increased to maximum-tolerated dosages. Injections with EQW or placebo were administered weekly, while oral medication or placebo was administered daily. RESULTS: Baseline characteristics were as follows: 59% men, 67% Caucasian, mean age 54 years, HbA(1c) 8.5%, fasting serum glucose 9.9 mmol/L, body weight 87.0 kg, and diabetes duration 2.7 years. HbA(1c) reductions (%) at 26 weeks (least-squares means) with EQW versus MET, PIO, and SITA were -1.53 vs. -1.48 (P = 0.620), -1.63 (P = 0.328), and -1.15 (P < 0.001), respectively. Weight changes (kg) were -2.0 vs. -2.0 (P = 0.892), +1.5 (P < 0.001), and -0.8 (P < 0.001), respectively. Common adverse events were as follows: EQW, nausea (11.3%) and diarrhea (10.9%); MET, diarrhea (12.6%) and headache (12.2%); PIO, nasopharyngitis (8.6%) and headache (8.0%); and SIT, nasopharyngitis (9.8%) and headache (9.2%). Minor (confirmed) hypoglycemia was rarely reported. No major hypoglycemia occurred. CONCLUSIONS: EQW was noninferior to MET but not PIO and superior to SITA with regard to HbA(1c) reduction at 26 weeks. Of the agents studied, EQW and MET provided similar improvements in glycemic control along with the benefit of weight reduction and no increased risk of hypoglycemia.

Oral protein kinase c ß inhibition using ruboxistaurin: efficacy, safety, and causes of vision loss among 813 patients (1,392 eyes) with diabetic retinopathy in the Protein Kinase C ß Inhibitor-Diabetic Retinopathy Study and the Protein Kinase C ß Inhibitor-Diabetic Retinopathy Study 2.

PURPOSE: To evaluate efficacy, safety, and causes of vision loss among 813 patients (1,392 eyes) with moderately severe to very severe nonproliferative diabetic retinopathy from the Protein Kinase C ß Inhibitor-Diabetic Retinopathy Study and Protein Kinase C ß Inhibitor-Diabetic Retinopathy Study 2 ruboxistaurin (RBX) protein kinase C ß inhibitor trials. METHODS: Patients in these 3-year, randomized, placebo-controlled, double-masked, Phase 3 trials had best-corrected Early Treatment Diabetic Retinopathy Study visual acuity ≥45 letters (∼20/125 Snellen), Early Treatment Diabetic Retinopathy Study retinopathy level 47A/B-53E, and no previous panretinal photocoagulation in ≥1 eye. Patients received placebo (N = 401) or RBX 32 mg/day (N = 412). Data from the 2 studies were combined and masked evaluation of retinal photographs was performed for cause of visual decline in all patients experiencing sustained moderate visual loss (≥15-letter loss sustained for the last 6 months of study). RESULTS: In the studies combined, sustained moderate visual loss occurred in 10.2% of placebo-treated patients versus 6.1% of RBX-treated patients (P = 0.011). A ≥15-letter gain occurred in 2.4% of placebo versus 4.7% of RBX eyes (P = 0.021) and a ≥15-letter loss occurred in 11.4% versus 7.4%, respectively (P = 0.012). Diabetic macular edema was the probable primary cause of vision loss. Among eyes without focal/grid photocoagulation at baseline, fewer RBX group eyes (26.7%) required initial focal/grid photocoagulation versus placebo (35.6%; P = 0.008). No safety concerns were identified. CONCLUSION: Analysis of data combined from two similar studies adds further statistical significance to RBX's beneficial effects on visual loss, need for focal laser, and vision gain, most likely through effects on macular edema.

Safety, tolerability, pharmacokinetics, and pharmacodynamics of exenatide once weekly in Japanese patients with type 2 diabetes.

This randomized, placebo-controlled, double-blind, parallel study assessed the safety, tolerability, pharmacokinetics, and pharmacodynamics of exenatide once weekly (QW) in 30 Japanese patients with type 2 diabetes (T2D) suboptimally controlled by diet and exercise alone or combined with biguanide, sulfonylurea, thiazolidinedione, or combinations of these agents (58.6% male; 58+/-9 years; body mass index 26.3+/-2.9 kg/m(2); hemoglobin A(1c) [HbA(1c)] 7.4+/-0.8%; fasting plasma glucose [FPG] 156.1+/-29.1 mg/dL; duration of T2D 6+/-5 years; means +/- SD). Patients were randomized in a 1:1:1 ratio to subcutaneous placebo QW, exenatide QW 0.8 mg, or exenatide QW 2.0 mg for 10 weeks. All evaluable patients were analyzed (placebo QW, n=10; exenatide QW 0.8 mg, n=10; exenatide QW 2.0 mg, n=9), unless otherwise stated. Steady-state plasma exenatide concentrations were observed by Week 8 of the study. For the evaluable pharmacokinetic population, geometric mean (90% confidence interval) steady-state plasma concentrations (pg/mL) were 81.2 (68.3-96.4) and 344.5 (256.5-462.7) with exenatide QW 0.8 mg (n=8) and exenatide QW 2.0 mg (n=5), respectively. Baseline-to-Week 10 glycemic improvements with placebo QW, exenatide QW 0.8 mg, and exenatide QW 2.0 mg, respectively, were: HbA(1c) (%): -0.4+/-0.3, -1.0+/-0.7, and -1.5+/-0.7; FPG (mg/dL): -20.5+/-20.4, -25.2+/-10.9, and -50.8+/-27.8; and 2-hour postprandial plasma glucose excursions (mg/dL): -8.8+/-26.9, -50.0+/-41.1, and -59.7+/-26.8 (means +/- SD). No serious adverse events (AEs) were reported and no AEs led to study discontinuation in any group. The most frequent AE observed was mild-to-moderate injection site induration. No serious hypoglycemia was reported. Exenatide QW for 10 weeks was well tolerated and improved short-term glycemic control in Japanese patients with suboptimally controlled T2D.

Effects of once-daily tadalafil on erectile function in men with erectile dysfunction and signs and symptoms of benign prostatic hyperplasia.

BACKGROUND: Lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH; BPH-LUTS) may be associated with erectile dysfunction (ED). OBJECTIVE: To evaluate the effects of once-daily tadalafil on erectile function in men with ED and BPH-LUTS. DESIGN, SETTING, AND PARTICIPANTS: Post hoc analysis of a phase 2-3, multinational, randomized, double-blind, placebo-controlled, parallel-group study of men with ED and moderate-to-severe LUTS secondary to BPH who reported being sexually active. In contrast to typical ED trials, no sexual activity threshold was required to participate. INTERVENTIONS: Screening and 4-wk washout period for patients taking BPH and/or ED treatments; 4-wk placebo run-in period; then once-daily placebo or tadalafil 2.5, 5, 10, or 20 mg for 12 wk. MEASUREMENTS: International Index of Erectile Function-Erectile Function (IIEF-EF) domain score, International Prostate Symptom Score (IPSS), peak urinary flow rate (Q(max)), and postvoid residual volume (PVR). Analyses were performed in men who reported being sexually active with a female partner and who expected to remain so throughout the study. IIEF-EF data are presented for the BPH/ED population overall and for subgroups stratified by baseline age group, body mass index, BPH-LUTS severity, prostate-specific antigen, prior alpha-blocker use, and prior ED therapy. RESULTS AND LIMITATIONS: Overall, 581 men were included (placebo, n=115; tadalafil 2.5 mg, n=113; tadalafil 5 mg, n=117; tadalafil 10 mg, n=120; tadalafil 20 mg, n=116). IIEF-EF domain score improvements from baseline to end point with tadalafil were 5.4 (2.5 mg), 6.8 (5 mg), 7.9 (10 mg), and 8.2 (20 mg) versus 2.0 with placebo (least-squares means; all p values <0.001). IIEF-EF domain score improvements were observed with tadalafil for all subgroup analyses, with no significant differences between subgroup or subgroup-by-treatment interaction terms. IPSS improvements from baseline to end point were significantly greater for all tadalafil doses versus placebo (all p values <0.05). Changes in Q(max) and PVR were small and not clinically meaningful. CONCLUSIONS: These data support the use of once-daily tadalafil in men with ED and BPH-LUTS. TRIAL REGISTRATION: http://www.clinicaltrials.gov: NCT00384930.

Exenatide exhibits dose-dependent effects on glycemic control over 12 weeks in Japanese patients with suboptimally controlled type 2 diabetes.

This study assessed the dose-dependent efficacy and safety of exenatide over 12 weeks in Japanese patients with type 2 diabetes suboptimally controlled despite therapeutic doses of sulfonylurea (SU), SU plus biguanide, or SU plus thiazolidinedione. Patients were randomly assigned to placebo (N = 40), 2.5 microg (N = 38), 5 microg (N = 37), or 10 microg (N = 38) exenatide administered subcutaneously twice daily (BID). Patients randomly assigned to 10 microg exenatide received 5 microg BID for the first 4 weeks, with the dose escalated to 10 microg BID for the final 8 weeks. Patients were 60.3 +/- 9.7 years old, with body mass index 25.3 +/- 4.3 kg/m(2) and hemoglobin A1c (HbA1c) 8.0 +/- 0.8%. Baseline-to-endpoint HbA1c changes (%) were +0.02 +/- 0.1 (placebo), -0.9 +/- 0.1 (2.5 microg), -1.2 +/- 0.1 (5 microg), and -1.4 +/- 0.1 (10 microg) (all p < 0.001 vs. placebo). Of patients with baseline HbA1c -7%, 5.1% (placebo), 50.0% (2.5 microg), 71.4% (5 microg), and 79.4% (10 microg) achieved HbA1c <7% at endpoint (p < 0.001, trend test). Baseline-to-endpoint fasting plasma glucose changes (mg/dL) were +6.0 +/- 4.8 (placebo), -18.6 +/- 5.7 (2.5 microg), -25.0 +/- 7.0 (5 microg), and -28.9 +/- 5.9 (10 microg) (all p < or = 0.001 vs. placebo). Treatment-emergent adverse events were mostly mild; dose-dependent increases in incidence were observed for hypoglycemia, nausea, anorexia, decreased appetite, and diarrhea (all p < or = 0.044, trend test). Over 12 weeks, exenatide dose-dependently improved glycemic control in Japanese patients with type 2 diabetes.

Efficacy and tolerability of exenatide monotherapy over 24 weeks in antidiabetic drug-naive patients with type 2 diabetes: a randomized, double-blind, placebo-controlled, parallel-group study.

BACKGROUND: Evaluation of exenatide monotherapy in patients with type 2 diabetes may be of clinical interest based on improvements in glycemic control and weight that have been reported with the use of exenatide in combination with oral antidiabetic agents. OBJECTIVE: The aim of this study was to evaluate the efficacy and tolerability of exenatide monotherapy in patients with type 2 diabetes naive to antidiabetic agents and whose disease was inadequately controlled with diet and exercise alone. METHODS: This 24-week, double-blind, placebo-controlled, parallel-group study was conducted at 23 centers across the United States, Puerto Rico, Romania, Russia, and India. Patients aged >or=18 years with type 2 diabetes were randomly assigned to receive exenatide 5 microg, exenatide 10 microg, or placebo administered SC BID. Patients were instructed by investigators to maintain their individualized prestudy diet and exercise regimens throughout the study. Efficacy measures included: glycosylated hemoglobin (HbA(1c)); fasting serum glucose (FSG); 6-point self-monitored blood glucose; percentages of patients achieving HbA(1c) values or=1 treatment-emergent adverse event. Nausea was reported with the greatest incidence (5 microg, 3%; 10 microg, 13%; placebo, 0%; P = 0.010 for the combined exenatide group vs placebo). Most (88%) treatment-emergent adverse events were mild or moderate in intensity. Hypoglycemia was reported in 5%, 4%, and 1% of patients in the exenatide 5- and 10-microg and placebo groups, respectively (P = NS), with no incidents of severe hypoglycemia reported. CONCLUSIONS: In these patients with type 2 diabetes naive to treatment with antidiabetic agents, exenatide monotherapy was associated with improved HbA(1c), improved fasting and postprandial glucose control, reduced weight, improved beta-cell function (HOMA-B), and improved blood pressure, and was well tolerated. These results suggest that exenatide monotherapy may provide a viable treatment option beyond diet and exercise and support further study of exenatide monotherapy in antidiabetic drug-naive patients with type 2 diabetes.

Long-term safety and efficacy of tadalafil 5 mg dosed once daily in men with erectile dysfunction.

INTRODUCTION: With once-daily administration of tadalafil, dosing and sexual activity would no longer need to be temporally linked for patients with erectile dysfunction (ED). AIM: To evaluate long-term safety and efficacy of tadalafil 5 mg dosed once daily for the treatment of ED. METHODS: Patients > or = 18 years of age with ED of any functional severity or etiology received tadalafil 5 mg once daily for 1 (N = 234) or 2 (N = 238) years during the open-label extensions of two previously reported studies. Patients who completed the 1-year open-label extension concluded with a 4-week ED treatment-free period. Baseline was defined as prior to receiving any study drug. MAIN OUTCOME MEASURES: Safety measures included adverse events, electrocardiograms, and clinical laboratory measures. Efficacy measures included the International Index of Erectile Function (IIEF)-Erectile Function (-EF), -Intercourse Satisfaction (-IS), and -Overall Satisfaction (-OS) domain scores, and the Global Assessment Questions (GAQ1: improved erections; GAQ2: improved ability to engage in sexual activity). RESULTS: Overall, 208/234 (88.9%) and 139/238 (58.4%) patients completed the 1- and 2-year open-label extensions, respectively. No study drug-related serious adverse events were observed. Treatment-emergent adverse events observed in > or = 5% of the patients during the first year of either open-label extension were dyspepsia, headache, back pain, and influenza. No clinically meaningful abnormalities associated with tadalafil were observed for electrocardiograms or clinical laboratory measures. Mean IIEF domain scores improved from baseline to the conclusions of the 1- and 2-year open-label extensions, respectively: -EF, +10.4 and +10.8; -IS, +4.0 and +3.7; and -OS, +3.0 and +3.2. At the conclusion of the 2-year open-label extension, 95.7% and 92.1% of the patients reported positive responses to GAQ1 and GAQ2, respectively. CONCLUSIONS: In these long-term, open-label, once-daily dosing studies, tadalafil 5 mg was well tolerated and effective, making it a viable alternative to the current on-demand dosing of tadalafil for men with ED.

A 6-month, randomized, double-masked, placebo-controlled study evaluating the effects of the protein kinase C-beta inhibitor ruboxistaurin on skin microvascular blood flow and other measures of diabetic peripheral neuropathy.

OBJECTIVE: Diabetes leads to protein kinase C (PKC)-beta overactivation and microvascular dysfunction, possibly resulting in disordered skin microvascular blood flow (SkBF) and other changes observed in diabetic peripheral neuropathy (DPN) patients. We investigate the effects of the isoform-selective PKC-beta inhibitor ruboxistaurin mesylate on neurovascular function and other measures of DPN. RESEARCH DESIGN AND METHODS: Endothelium-dependent and C fiber-mediated SkBF, sensory symptoms, neurological deficits, nerve fiber morphometry, quantitative sensory and autonomic function testing, nerve conduction studies, quality of life (using the Norfolk Quality-of-Life Questionnaire for Diabetic Neuropathy [QOL-DN]), and adverse events were evaluated for 20 placebo- and 20 ruboxistaurin-treated (32 mg/day) DPN patients (aged > or =18 years; with type 1 or type 2 diabetes and A1C < or =11%) during a randomized, double-masked, single-site, 6-month study. RESULTS: Endothelium-dependent (+78.2%, P < 0.03) and C fiber-mediated (+56.4%, P < 0.03) SkBF at the distal calf increased from baseline to end point. Significant improvements from baseline within the ruboxistaurin group were also observed for the Neuropathy Total Symptom Score-6 (NTSS-6) (3 months -48.3%, P = 0.01; end point -66.0%, P < 0.0006) and the Norfolk QOL-DN symptom subscore and total score (end point -41.2%, P = 0.01, and -41.0, P = 0.04, respectively). Between-group differences in baseline-to-end point change were observed for NTSS-6 total score (placebo -13.1%; ruboxistaurin -66.0%, P < 0.03) and the Norfolk QOL-DN symptom subscore (placebo -4.0%; ruboxistaurin -41.2%, P = 0.041). No significant ruboxistaurin effects were demonstrated for the remaining efficacy measures. Adverse events were consistent with those observed in previous ruboxistaurin studies. CONCLUSIONS: In this cohort of DPN patients, ruboxistaurin enhanced SkBF at the distal calf, reduced sensory symptoms (NTSS-6), improved measures of Norfolk QOL-DN, and was well tolerated.

Effect of growth hormone dose on bone maturation and puberty in children with idiopathic short stature.

CONTEXT: GH at 0.22 mg/kg.wk has been shown to have no effect on pubertal onset or pace, whereas GH at 0.5 mg/kg x wk has been shown to advance pubertal onset and bone maturation. OBJECTIVES: Our objectives were to determine whether 0.37 mg/kg x wk GH advanced pubertal onset, pace, or bone maturation relative to 0.24 mg/kg x wk GH; whether 0.37 mg/kg x wk GH led to pubertal onset at an inappropriately early age; and whether age at start of GH therapy influenced pubertal onset. DESIGN: We conducted a randomized, open-label study to final height. PATIENTS: We studied children with idiopathic short stature. INTERVENTION: Patients were treated with 0.24 mg/kg x wk, 0.24 increasing to 0.37 mg/kg x wk, or 0.37 mg/kg x wk. MAIN OUTCOME MEASURES: We assessed age at pubertal onset and rates of bone maturation, Tanner stage development, and increase in testicular volume (boys only). RESULTS: For the primary comparison between the 0.24 and 0.37 mg/kg x wk dose groups, median ages of pubertal onset (in years) were similar (13.7 vs. 13.5 for boys and 11.7 vs. 11.4 for girls) and were greater than those for the general population for each sex. Age at start of GH therapy did not appear to influence pubertal onset for either sex. Rates of pubertal pace and bone maturation were not significantly different between the 0.24 and 0.37 mg/kg x wk dose groups for either sex. CONCLUSION: GH at 0.37 mg/kg x wk does not appear to accelerate pubertal onset, pace, or bone maturation compared with GH at 0.24 mg/kg x wk in patients with idiopathic short stature. From a clinical standpoint, our results suggest that the approved dose range of up to 0.37 mg/kg x wk GH does not lead to pubertal onset at an inappropriately early age.

Safety of growth hormone treatment in pediatric patients with idiopathic short stature.

CONTEXT: Recombinant human GH was approved by the United States Food and Drug Administration in 2003 for the treatment of idiopathic short stature (ISS). However, to date, the safety of GH in this patient population has not been rigorously studied. OBJECTIVE: The objective of this study was to address the safety of GH treatment in children with ISS compared with GH safety in patient populations for which GH has been approved previously: Turner syndrome (TS) and GH deficiency (GHD). DESIGN/SETTING: The rates of serious adverse events (SAEs) and adverse events (AEs) of particular relevance to GH-treated populations were compared across the three patient populations among five multicenter GH registration studies. PATIENTS: Children with ISS, TS, or GHD were studied. INTERVENTION: Treatment consisted of GH doses ranging from 0.18-0.37 mg/kg.wk. MAIN OUTCOME MEASURES: The main outcome measures were rates of SAEs and AEs of special relevance to patients receiving GH. Laboratory measures of carbohydrate metabolism were used as outcome measures for the ISS studies. RESULTS: Within the ISS studies, comprising one double-blind, placebo-controlled study and one open-label, dose-response study, SAEs (mainly hospitalizations for accidental injury or acute illness unrelated to GH exposure) were reported for 13-14% of GH-treated patients. Overall AE rates (serious and nonserious) as well as rates of potentially GH-related AEs were similar in the GHD, TS, and ISS studies (for ISS studies combined: otitis media, 8%; scoliosis, 3%; hypothyroidism, 0.7%; changes in carbohydrate metabolism, 0.7%; hypertension, 0.4%). Measures of carbohydrate metabolism were not affected by GH treatment in patients with ISS. There was no significant GH effect on fasting blood glucose in either study (GH dose range, 0.22-0.37 mg/kg.wk) or on insulin sensitivity (placebo-controlled study only). CONCLUSION: GH appears safe in ISS; however, the studies were not powered to assess the frequency of rare GH-related events, and longer-term follow-up studies of GH-treated patients with ISS are warranted.

The interaction of the penetration enhancer DDAIP with a phospholipid model membrane.

Differential scanning calorimetry (DSC) was used to investigate the mechanism of action of a proprietary skin penetration enhancer, dodecyl-2-(N,N-dimethylamino)propionate (DDAIP) in dipalmitoylphosphatidylcholine (DPPC) liposomes. Furthermore, the effect of enhancer concentration on lipid thermotropic transitions was investigated. With increasing concentrations of DDAIP (from 5 to 50 mol%), the main transition peak shifted to lower temperatures and became more broad. The pretransition peak also shifted to lower temperatures with increasing concentrations of DDAIP and disappeared completely above an enhancer concentration of 20 mol%. Main transition and pretransition enthalpies of reaction decreased with increasing DDAIP concentration, indicating that enhancer treatment destabilized both rippled gel and liquid crystal phases within the bilayer. At and above a DDAIP concentration of 33.3 mol%, an additional transition was evident, indicating the presence of two phases of enhancer-lipid complex. Results suggest that DDAIP enhances drug transport by interacting with the polar region of the phospholipid bilayer and also by increasing the motional freedom of lipid hydrocarbon chains.

Pain and the blood-brain barrier: obstacles to drug delivery.

Delivery of drugs across the blood-brain barrier has been shown to be altered during pathological states involving pain. Pain is a complex phenomenon involving immune and centrally mediated responses, as well as activation of the hypothalamic-pituitary-adrenal axis. Mediators released in response to pain have been shown to affect the structure and function of the blood-brain barrier in vitro and in vivo. These alterations in blood-brain barrier permeability and cytoarchitecture have implications in terms of drug delivery to the central nervous system, since pain and inflammation have the capacity to alter drug uptake and efflux across the blood-brain barrier. An understanding of how blood-brain barrier and central nervous system drug delivery mechanisms are altered during pathological conditions involving pain and/or inflammation is important in designing effective therapeutic regimens to treat disease.