PIPELINEs: Creating Comparable Clinical Knowledge Efficiently by Linking Trial Platforms.

Adaptive, seamless, multisponsor, multitherapy clinical trial designs executed as large scale platforms, could create superior evidence more efficiently than single-sponsor, single-drug trials. These trial PIPELINEs also could diminish barriers to trial participation, increase the representation of real-world populations, and create systematic evidence development for learning throughout a therapeutic life cycle, to continually refine its use. Comparable evidence could arise from multiarm design, shared comparator arms, and standardized endpoints-aiding sponsors in demonstrating the distinct value of their innovative medicines; facilitating providers and patients in selecting the most appropriate treatments; assisting regulators in efficacy and safety determinations; helping payers make coverage and reimbursement decisions; and spurring scientists with translational insights. Reduced trial times and costs could enable more indications, reduced development cycle times, and improved system financial sustainability. Challenges to overcome range from statistical to operational to collaborative governance and data exchange.

Fine-scale quantification of HCG beta gene transcription in human trophoblastic and non-malignant non-trophoblastic tissues.

Human chorionic gonadotropin (HCG) is produced by syncytiotrophoblast of placenta. It delays the apoptosis of corpus luteum and functions in implantation. Its possible role in male reproduction has been raised. HCG beta subunit is encoded by CGB, CGB5, CGB7 and CGB8 genes located at 19q13.3 in a common genome cluster with beta subunit non-coding CGB1 and CGB2. We conducted a sensitive quantification and comparison of CGB gene expression in human trophoblastic (blastocysts, n = 6; normal/failed pregnancy, n = 51) and non-malignant non-trophoblastic tissues (15 different tissue types, samples n = 241), by real-time RT-PCR. We showed a wide transcriptional window of CGB genes in normal pregnancy, a significant reduction in recurrent miscarriages, and a high expression (especially CGB1/CGB2) in ectopic and molar pregnancies. Expression was several orders of magnitude lower in the non-placental tissues, with the highest CGB levels being seen in testis, prostate, thymus, skeletal muscle and lung samples. The contribution of CGB1/CGB2 to the summarized expression of six CGB genes was not proportional to their gene dosage: 1/1000 to 1/10,000. An interesting exception was the testis exhibiting a much higher CGB1/CGB2 to total CGB mRNA ratio of approximately one-third, corresponding to gene dosage. In conclusion, the expressional profile of CGB genes, activated already in blastocyst stage, is associated with the status of pregnancy. The presence of CGB transcripts in testes, and in particular CGB1/CGB2 transcripts, may indicate a role in male reproductive tract.

Role of cADPR in sodium nitroprusside-induced opossum esophageal longitudinal smooth muscle contraction.

Nitric oxide (NO) relaxes most smooth muscle, including the circular smooth muscle (CSM) of the esophagus, whereas in the adjacent longitudinal smooth muscle (LSM), it causes contraction. The second messenger pathways responsible for this NO-induced LSM contraction are unclear, given that these opposing effects of NO are both cGMP dependent. In intestinal LSM, but not CSM, cADP ribose (cADPR)-dependent pathways participate in Ca(2+) mobilization and muscle contraction; whether similar differences exist in the esophagus is unknown. The purpose of this study was to determine whether cADPR plays a role in the NO-mediated contraction of opossum esophageal LSM. Standard isometric tension recordings were performed using both LSM and CSM strips from opossum distal esophagus that were hung in 10-ml tissue baths perfused with oxygenated Krebs solution. cADPR produced concentration-dependent contraction of LSM strips with an EC(50) of 1 nM and peak contraction of 57 +/- 18% of the 60 mM KCl-induced contraction. cADPR had no effect on CSM strips at concentrations up to 10(-6) M. The EC(50) of cADPR caused contraction (18 +/- 2% from initial resting length) of isolated LSM cells. Sodium nitroprusside (SNP; 300 muM) induced contraction of LSM strips that averaged 67 +/- 5% of the KCl response. cADPR antagonists 8-bromo-cADPR and 8-amino-cADPR, as well as ryanodine receptor antagonists ryanodine and tetracaine, significantly inhibited the SNP-induced contraction. In conclusion, in the opossum esophagus, 1) cADPR induces contraction of LSM, but not CSM, and 2) NO-induced contraction of LSM appears to involve a cADPR-dependent pathway.

A survey of the perceptions, knowledge, and use of A1C values by home care patients and nurses.

PURPOSE: The purpose of this study was to provide baseline information on the perceptions, use, and knowledge of hemoglobin A1C (A1C) values among home healthcare nurses and patients. METHODS: A convenience sample (44 patients, 26 nurses) from a Medicare-certified home care agency was surveyed using an investigator-developed demographic and knowledge questionnaire. Data collected from telephone interviews (patients), written questionnaires (nurses), and medical record reviews were analyzed using descriptive methods. RESULTS: Most of the home care nurses correctly identified the American Diabetes Association's recommendation for target A1C values; however, nurses rarely contact the physician to obtain A1C results. Nurses do not routinely teach patients about A1C values and inconsistently use A1C values to plan care for their patients with diabetes. Most patients said that they had never had an A1C test performed, and most did not recall the nurse providing any teaching about A1C. CONCLUSIONS: Education related to target A1C values is needed. Methods to increase the availability of A1C results in the home care setting should be explored. The importance and clinical utility of A1C values need to be more effectively conveyed to both nurses and patients in the home care setting.

Nateglinide therapy for type 2 diabetes mellitus.

OBJECTIVE: To review the pharmacology, pharmacokinetics, dosing guidelines, adverse effects, drug interactions, and clinical efficacy of nateglinide. DATA SOURCES: Primary and review articles regarding nateglinide were identified by MEDLINE search (from 1966 to January 2001); abstracts were identified through the Institute for Scientific Information Web of Science (from 1995 to January 2001) and the American Diabetes Association; additional information was obtained from the nateglinide product information. STUDY SELECTION/DATA EXTRACTION: All articles and meeting abstracts identified from the data sources were evaluated and all information deemed relevant was included in this review. Much of the information was from abstracts or the product labeling, since few clinical studies have been published in the medical literature. DATA SYNTHESIS: Nateglinide is a novel nonsulfonylurea oral antidiabetic agent that stimulates insulin secretion from the pancreas. It has a rapid onset and short duration of action, allowing administration before a meal to reduce postprandial hyperglycemia. Improvement in glycemic control with nateglinide monotherapy has been demonstrated in patients not previously treated with antidiabetic medications. Greater improvement in glycemic control was observed when nateglinide was administered in combination with metformin. CONCLUSIONS: Nateglinide is similar to repaglinide, but has a quicker onset of action, quicker reversal, and does not usually require dosage titration. Based on the pharmacodynamics of nateglinide and repaglinide, nateglinide produces a more rapid postprandial increase in insulin secretion, and its duration of response is shorter than that of repaglinide. The risk of postabsorptive hypoglycemia should be lower than with either sulfonylureas or repaglinide.

Threading of a glycosylated protein loop through a protein hole: implications for combination of human chorionic gonadotropin subunits.

Chorionic gonadotropin (hCG) is a heterodimeric placental glycoprotein hormone essential for human reproduction. Twenty hCG beta-subunit residues, termed the seatbelt, are wrapped around alpha-subunit loop 2 (alpha 2) and their positions "latched" by a disulfide formed by cysteines at the end of the seatbelt (Cys 110) and in the beta-subunit core (Cys 26). This unique arrangement explains the stability of the heterodimer but raises questions as to how the two subunits combine. The seatbelt is latched in the free beta-subunit. If the seatbelt remained latched during the process of subunit combination, formation of the heterodimer would require alpha 2 and its attached oligosaccharide to be threaded through a small beta-subunit hole. The subunits are known to combine during oxidizing conditions in vitro, and studies described here tested the idea that this requires transient disruption of the latch disulfide, possibly as a consequence of the thioredoxin activity reported in hCG. We observed that alkylating agents did not modify either cysteine in the latch disulfide (Cys 26 or Cys 110) during heterodimer formation in several oxidizing conditions and had minimal influence on these cysteines during combination in the presence of mild reductants (1--3 mM beta-mercaptoethanol). Reducing agents appeared to accelerate subunit combination by disrupting a disulfide (Cys 93--Cys 100) that forms a loop within the seatbelt, thereby increasing the size of the beta-subunit hole. We propose a mechanism for hCG assembly in vitro that depends on movements of alpha 2 and the seatbelt and suggest that the process of glycoprotein hormone subunit combination may be useful for studying the movements of loops during protein folding.

Insulin glargine.

BACKGROUND: In diabetes mellitus, the clinical goal of intensive glycemic control (lowering blood glucose concentrations to normal or near-normal levels) has been hindered by the lack of insulin regimens that duplicate the basal-bolus secretion of insulin by the healthy pancreas. In particular, intensive therapy has been associated with a risk of hypoglycemia. OBJECTIVE: This article reviews the pharmacology, pharmacokinetics, dosing guidelines, adverse effects, and potential drug interactions of insulin glargine, a new long-acting recombinant human insulin analogue. Results of clinical trials of its efficacy and tolerability as a basal insulin in the treatment of type 1 and type 2 diabetes are summarized. METHODS: Primary research and review articles on insulin glargine were identified through a search of MEDLINE from 1966 to July 2001. Abstracts were identified through a search of the Institute for Scientific Information Web of Science from 1995 to July 2001 and proceedings of American Diabetes Association scientific meetings. Additional information was obtained from the product information for insulin glargine. All identified articles and abstracts were evaluated for relevance, and all relevant information was included in the review. Priority was given to data from the primary medical literature. RESULTS: Insulin glargine has a slower onset of action than human neutral protamine Hagedorn (NPH) insulin, a longer duration of action (up to 24 hours), and no pronounced peak. It has similar tolerability and produces similar glycemic control to once- or twice-daily human NPH insulin, with a similar glucose-lowering effect on a molar basis. A decreased incidence of hypoglycemia, particularly at night, has been reported with insulin glargine compared with human NPH insulin. Insulin glargine appears to be comparable to human NPH insulin in terms of toxicity, adverse effects, immunogenicity, and potential for drug interactions. Results of clinical trials of insulin glargine in both type 1 and type 2 diabetes support its use in combination with a short-acting insulin, insulin lispro, or oral antidiabetic medications. Although insulin glargine cannot be mixed with other insulin preparations, it has the potential convenience of providing basal insulin with once-daily bedtime dosing. CONCLUSIONS: Based on the as yet small amount of data from full clinical study reports in peer-reviewed publications, insulin glargine appears to be a well-tolerated and effective basal insulin preparation for patients with type 1 or type 2 diabetes (including pediatric patients). Its delayed onset of action and prolonged, flat time-action profile mimic the action of endogenous basal insulin (or an insulin pump), decreasing the risk of hypoglycemic episodes. Insulin glargine may be a useful new option for meeting overnight insulin requirements, although most patients will require a rapid-acting insulin such as insulin lispro with or before meals for optimal management of blood glucose levels.

Miglitol: assessment of its role in the treatment of patients with diabetes mellitus.

OBJECTIVE: To evaluate miglitol, a new oral alpha-glucosidase inhibitor, and discuss its pharmacology, therapeutics, pharmacokinetics, dosing guidelines, adverse effects, drug interactions, and clinical efficacy. DATA SOURCES: A MEDLINE English-language only database search using the keywords miglitol, glyset, and Bay m 1099 (1985 to December 1999), was completed to identify relevant articles including reviews, recent studies, and abstracts; American Diabetes Association 1999 Annual Meeting abstracts; Pharmacia & Upjohn data on file and product information. STUDY SELECTION: The clinical trials that were selected to be reviewed in detail were randomized, double-blind studies with at least 100 patients in the intention-to-treat group. DATA EXTRACTION: All articles and abstracts were reviewed along with the product labeling from Pharmacia & Upjohn. DATA SYNTHESIS: Miglitol is an alpha-glucosidase inhibitor that exerts its effect through the delayed absorption of complex carbohydrates in the small intestine, resulting in a decrease in postprandial glucose concentrations that are directly correlated with the dietary carbohydrate content. Both small, short-term trials and large, clinical trials show a decrease in postprandial glucose concentrations and a modest decrease in glycosylated hemoglobin of approximately 0.5-1.0% as a result of miglitol's action. The adverse effects of miglitol are mild and transitory and include flatulence, diarrhea, and abdominal pain. The incidence of gastrointestinal problems may be reduced with a small initial dose, which is slowly titrated as tolerated. CONCLUSIONS: Miglitol is an effective and safe treatment option in patients with type 2 diabetes mellitus who are inadequately controlled with diet or oral sulfonylurea therapy. Miglitol is a good choice of therapy in Hispanic, African-American, and elderly patients, or any patients in whom hypoglycemia, weight gain, or lactic acidosis are risks. No published studies comparing miglitol with acarbose have been published, but there appears to be no major clinical or financial advantages to using one agent over the other.

The latest developments in insulin injection devices.

The next several years promise dramatic changes in the treatment of diabetes, many of which will be driven by rapidly developing technology. Today's patient with diabetes has ready access to more information about the disease and its treatment options. As a result of this increased knowledge base, insulin-treated patients have become more autonomous in the management of their diabetes and may be better prepared to participate in making informed choices regarding insulin delivery devices. As with any insulin regimen, diabetes educators are encouraged to provide ongoing patient education and follow-up to assure optimal use of these new technologies.

Insulin aspart: a new rapid-acting insulin analog.

OBJECTIVE: To examine the pharmacology, therapeutics, pharmacokinetics, dosing guidelines, adverse effects, and drug interactions of insulin aspart, and summarize the clinical trials of efficacy and safety in patients with type or type 2 diabetes mellitus. DATA SOURCES: A MEDLINE database search (1985-May 2000) was performed to identify all applicable published articles and abstracts; in some cases, Novo Nordisk unpublished information was also obtained. Review articles on insulin analogs were also identified, as well as review chapters in medical textbooks. STUDY SELECTION: The majority of the studies identified were in abstract form. These studies reported information on the pharmacokinetics of insulin aspart in healthy volunteers and in those with diabetes, as well as the therapeutic utility, safety, and clinical efficacy in patients with diabetes. A limited number of randomized studies were reported as artices in the medical literature DATA EXTRACTION: All published clinical studies were reviewed. DATA SYNTHESIS: Insulin aspart, the second Food and Drug Administration-approved rapid-acting insulin analog, is produced by recombinant technology that replaces the proline at position 28 on the B chain of insulin with negatively charged aspartic acid. Insulin aspart exists as hexamers that rapidly dissociate into monomers and dimers on subcutaneous injection. When administered immediately prior to a meal, insulin aspart is at least as effective as regular human insulin in control of postprandial blood glucose concentrations. Insulin aspart achieves higher peak insulin concentrations in less time and with a shorter duration of action than regular human insulin. CONCLUSIONS: Insulin aspart is a convenient premeal insulin for use by patients requiring mealtime insulin. Furthermore, due to favorable pharmacokinetics, insulin aspart controls postprandial blood glucose concentrations at least as well as regular human insulin and contributes to improved quality of life.

Dangerous and common drug interactions in patients with diabetes mellitus.

As more medications are made available to the prescriber, the likelihood of drug interactions will increase. The number of drug interactions encountered by the provider treating the patient with diabetes has increased over the past few years because the number of medications used in the management of hyperglycemia has dramatically increased during that time. These interactions are complex but can be predicted.

Lispro insulin: adsorption and stability in selected intravenous devices.

PURPOSE: The adsorption characteristics and stability profile of an insulin analog, lispro insulin, were evaluated against a recombinant human regular insulin using intravenous infusion sets and syringes. METHODS: Studies were performed using either 0.9% NaCl or 5% dextrose intravenous injection solution. Effects of container type, infusion rate, product concentration, presence-absence of an in-line filter, and storage condition on release profiles of lispro and human regular insulin infusion solutions were determined. RESULTS: Lispro insulin and m-cresol were chemically stable. Release rates of insulin (both types) were steady after an initial lag time. The lag time was much longer with intravenous bag infusion than with intravenous syringe infusion. A higher product concentration, faster flow rate, and prewash of the infusion tubing were shown to substantially decrease the lag time. CONCLUSIONS: The adsorption profile of lispro insulin was the same as that of human regular insulin in both syringes and bags. Use of a load-and-sit prewash scheme may shorten or nearly eliminate the lag time, which in turn may be used to make a more accurate calculation of a patient's dose.

Glimepiride: role of a new sulfonylurea in the treatment of type 2 diabetes mellitus.

OBJECTIVE: To review the clinical pharmacology data regarding the sulfonylurea glimepiride, and to summarize the clinical trials of glimepiride efficacy and safety alone and in combination with insulin for the treatment of type 2 diabetes mellitus. DATA SOURCES: A MEDLINE database search (English language, January 1985-April 1997) was performed to identify relevant published articles, including reviews and abstracts; the manufacturer (Hoechst Marion Roussel, Kansas City, MO) provided unpublished data. STUDY SELECTION: Pharmacology information was taken from representative original research articles. Eight clinical studies were selected for analysis on the basis of large enrollment, appropriate study design, and publication of results. DATA EXTRACTION: All clinical trials, published and unpublished, were reviewed. DATA SYNTHESIS: Glimepiride is a sulfonylurea that is pharmacologically distinct from other sulfonylureas because of differences in receptor-binding properties and potentially selective effects on ATP-sensitive K+ channels. The pharmacokinetic and pharmacodynamic profile of glimepiride makes it suitable for once-daily dosing. The safety and efficacy of glimepiride have been confirmed in studies involving more than 5000 patients with type 2 diabetes. In one study, once-daily doses of 1-8 mg reduced fasting plasma glucose from baseline by 43-74 mg/dL more than did placebo (p < 0.001), and hemoglobin (Hb) A1C values decreased by 1.2-1.9% more than with placebo (p < 0.001). Two-thirds of patients achieved tight control (i.e., HbA1C < or = 7.2%). Glimepiride was as effective as second-generation sulfonylureas. The most common adverse events were dizziness and headache, but no single adverse event occurred in more than 2% of patients. CONCLUSIONS: Glimepiride appears to be a useful option for patients with type 2 diabetes not controlled by diet and exercise and who want to achieve tight glucose control. Glimepiride can be used alone, in combination with other antihyperglycemic agents, or in patients with secondary sulfonylurea failure, as an adjunct to insulin therapy.

Providing pharmaceutical care in a physician office.

OBJECTIVE: To develop a physician office-based pharmaceutical care practice and evaluate the impact on the participating physicians, their staff, and patients. SETTING: Internal medicine physician office. PRACTICE DESCRIPTION: Two physicians and two nurses practice in a medical office complex in a rural setting in eastern Washington. PRACTICE INNOVATION: Development of an experimental pharmaceutical care program in which a registered pharmacist works in a physician office to evaluate the medication needs of patients and to provide pharmaceutical care and medication information to health professionals and patients. MAIN OUTCOME MEASURES: Functions and interventions performed by the pharmacist; types of disease states in patients that were confronted by the pharmacist; summary of time spent with patients; and attitudes of physicians and patients concerning the pharmacist interventions. RESULTS: 660 pharmacist interventions or functions occurred during the seven months of the project. Of 107 recommendations to the physicians concerning changes in therapy, 89 were accepted. Patients suffered from 53 different disease states that were evaluated by the pharmacist. The pharmacist spent from less than 5 minutes to more than an hour with individual patients, 5 to 15 minutes with the majority of patients. Both patients and physicians were impressed with the service and strongly desired to have it continued. CONCLUSION: There is a career opportunity for pharmacists to provide pharmaceutical care in the setting of a physician office practice. Many of the barriers to providing pharmaceutical care can be eliminated or diminished in this setting.

Natural products and diabetes treatment.

Many natural products are promoted to improve the health status of patients with diabetes by people making a profit on these products. Few of these claims have any scientific basis. Certain natural products are potentially damaging to patients with chronic diseases, especially if the products are used instead of proven scientific treatment regimens. Many individuals believe that if a product is natural it must be effective and safe. What is ironic is that if the products were safe and effective, and if studies would have been done on humans to prove safety and effectiveness, the sales of the products would greatly increase (as opposed to present limited sales as herbs from health food stores). Some of the products do have a beneficial effect, especially as a placebo if the patient believes that the product is going to work. As can be seen from the summary of products that are listed here that claim to improve the treatment of patients with diabetes, very few are available in a standard form that would produce a known positive effect. The few products that do have a mild impact on lowering blood glucose levels are much less effective than standard treatments. In a recent review of the role of plant-derived drugs and herbal medicines in healthcare, no natural products were listed as having a beneficial effect on diabetes. Diabetes care providers need to confront the issue of the use of natural products with their patients. Patients should be taught the importance of using proven, effective treatment regimens. Any patient who decides to use a natural product should be followed closely to make sure that no toxic effects occur and that treatment objectives are achieved.