Perceptions of Practicing Pharmacists in Idaho about a Potential Behind-the-Counter Drug Program

Background:

In late 2007, the Food and Drug Administration (FDA) held public hearings exploring the establishment of a new behind-the-counter (BTC) drug program. However, little is known about the views ol pharmacists regarding such a program.

Objective:

To assess the overall perceptions of Idaho's practicing pharmacists about the creation of a formal BTC drug program, the appropriateness of including certain drug categories, specific barriers to its adoption, and the impact of the new program on access to medicines.

Methods:

A survey of practicing pharmacists in Idaho was conducted by mail, utilizing anonymous responses. Key questions exploring the views of pharmacists about the new BTC drug program utilized 5-point Likert scales. Data were also collected on respondent characteristics.

Results:

A total of 357 practicing pharmacists in Idaho (31% response rate) returned the mail survey; 84% of pharmacists agreed that the FDA should be exploring an expanded BTC program, and 88% of pharmacists agreed that this program would improve access to some prescription-only products and convenience (or patients. Almost 71% of pharmacists reported a personal willingness to both initiate and monitor certain BTC drug therapies. When focusing on specific drug categories for BTC status, the highest support was (or selected agents within smoking cessation therapies (85%). nasal corticosteroids for allergies (81%). and vaccines (75%). Pharmacists who reported low barriers to the adoption of a new BTC program were significantly more likely to support this program than were those reporting high barriers. Only 39% of pharmacists agreed that adequate facilities were currently available for private evaluation and counseling of BTC patients.

Conclusions:

Pharmacists in a statewide survey of perceptions regarding a new BTC drug program overwhelmingly believe that patients would benefit. Pharmacists strongly support the development of the new program, and more than two thirds indicate that they would likely participate, given the necessary supporting institutional framework. Perceived barriers are related to willingness to participate and likely can be minimized through education and provision of private consulting areas.

Willingness to pay for cancer prevention

Cancer inflicts great pain, burden and cost upon American society, and preventing cancer is important but not costless. The aim of this review was to explore the upper limits that American society is paying and appears willing to pay to prevent cancer, by enforced environmental regulations and implemented clinical practice guidelines. Cost-effectiveness studies of clinical and environmental cancer-prevention policies and programmes were identified through a comprehensive literature review and confirmed to be officially sanctioned and implemented, enforced or funded. Data were collected in 2005-6 and analysed in 2007. The incremental cost-effectiveness ratios (ICERs) for clinical prevention policies ranged from under $US2000 to over $US6 000 000 per life-year saved (LYS), exceeding $US100 000 per LYS for only 11 of 101 guidelines. Median ICERs for tobacco-related ($US3978/LYS), colorectal ($US22 694/LYS) and breast ($US25 687/LYS) cancer prevention were within generally accepted ranges and tended not to vary greatly, whereas those for prostate ($US73 603/LYS) and cervical ($US125 157/LYS) cancer-prevention policies were considerably higher and varied substantially more. In contrast, both the median and range of the environmental policies were enormous, with 90% exceeding $US100 000 per LYS, and ICERs ranging from $US61 004 to over $US24 billion per LYS. Notwithstanding a relatively large and accessible literature evaluating the cost effectiveness of clinical and environmental cancer-prevention policies as well as the availability of ICERs for the policies identified in this study, the apparent willingness to pay to prevent cancer in the US still varies greatly and can be extremely high, particularly for many of the environmental cancer-prevention policies.

Counter sampling combined with medical provider education: do they alter prescribing behavior?

OBJECTIVE

To observe if medical providers alter their prescribing patterns of three relatively expensive categories of medications provided as samples by manufacturers (focus medications) when they receive additional education from pharmacists concerning the appropriate use of lower cost alternatives (counter samples) that are made available to dispense.

DESIGN

Pretest, post-test with a control group.

SETTING

Two rural, private care clinics in southeastern Idaho providing immediate care services.

PARTICIPANTS

Eight medical providers at a clinic where interventions were employed (active intervention group) and seven medical providers in a clinic where no interventions occurred (control group).

INTERVENTIONS

Medical providers in the active intervention group had: 1) education from pharmacists concerning the appropriate use of lower-cost alternatives compared with expensive focus medications 2) counter samples and patient sample handouts available to dispense to patients at their own discretion.

MAIN OUTCOME MEASURES

The percentage of the total yearly prescriptions for nonsteroidal anti-inflammatory drugs (NSAIDs), antihistamines, and acid-relief medications that consisted of focus-COX-2 NSAIDs, nonsedating antihistamines, and proton pump inhibitors (PPIs), respectively.

RESULTS

The prescribing behavior of medical providers in the active intervention and control groups were significantly different at baseline in all three categories of focus medications. This suggested that the results should focus on changes across the two years of the study within the intervention and control groups rather than across the two groups. Medical providers in the intervention group significantly decreased the use of COX-2 NSAID prescriptions relative to total NSAID prescriptions following active intervention (38.9% in year 1 versus 23.7% in year 2, P < 0.05). Over the same two time periods, a nonstatistically significant decrease in COX-2 NSAID prescribing was seen at the control site (67.5% versus 62%, P > 0.05). Education and counter sampling did not stop medical providers from significantly increasing the total yearly prescriptions for antihistamines and acid-relief medications that consisted of focus-nonsedating antihistamines (86.7% versus 93.1%, P < 0.05) and PPIs (68.9% versus 86.2%, P < 0.05). Statistically significant increases in the prescribing of focus-nonsedating antihistamines (77.9% versus 98.3%, P < 0.05) and PPIs (77.5% versus 91.4%, P < 0.05) were also observed in the control group.

CONCLUSIONS

Education by pharmacists, combined with access to counter samples, may or may not have an effect on medical provider prescribing, depending on the category of medication targeted for cost control.

Analyzing oncology clinical trial data using the Q-TWiST method: clinical importance and sources for health state preference data

PURPOSE

The Quality-adjusted Time Without Symptoms of disease and Toxicity (Q-TWiST) analysis method is frequently applied to evaluating outcomes in cancer clinical trials, but there is little information on what constitutes a clinically important difference (CID). We reviewed the Q-TWiST, health-related quality of life (HRQL) and utility measurement literature to develop recommendations for CID for the Q-TWiST. We also provide recommendations for measuring health utilities and for the design of Q-TWiST studies.

METHODS

The English language literature was searched between 1986 and 2003 for Q-TWiST studies in oncology. We estimated the percent differences between treatments based on median follow-up duration for overall, progression-free and quality-adjusted survival. We also reviewed the relevant HRQL and utility literature on clinical importance.

RESULTS

The overall differences between treatments for most (56%) of the observed, published values for Q-TWiST analyses ranged between 12% and 19%. Three-fourths of the Q-TWiST studies had gains in survival of 12%-17%, while differences in progression-free survival ranged from 12% to 26%. Studies that have evaluated the clinical importance of changes in HRQL scores suggest that changes of 5%-10% are clinically meaningful, and other research suggests that 0.5 standard deviation is a reasonable threshold for changes in HRQL for chronic diseases. Similarly, one guideline from the health state utility literature is that a 5%-10% difference in standard gamble utility scores is clinically important. Various sources are available for health utilities for Q-TWiST studies and the most valid are derived from patients or the general public, although most studies rely on sensitivity analyses with no collection of utilities.

CONCLUSIONS

We recommend that the CID for Q-TWiST is 10% of overall survival in a study, and differences of 15% are clearly clinically important. If less is known about a specific treatment and/or disease area, the CID should be greater than 5% but not more than 10% in planning sample size and statistical power. These CID estimates should be interpreted with caution, pending confirmation in future studies by direct patient assessment of the clinically relevant health states for Q-TWiST.

Surveillance patterns and polyp recurrence following diagnosis and excision of colorectal polyps in a medicare population

OBJECTIVE

Study objectives were to determine surveillance and polyp recurrence rates among older, increased-risk patients who have been diagnosed and excised of colorectal polyps. The high incidence of colorectal cancers in the Medicare-eligible population, the strong evidence linking reductions in mortality from colorectal cancer by removal of colorectal polyps, and the paucity of postpolypectomy surveillance data in this population all supported the need for this study.

METHODS

This retrospective study used Medicare claims data to identify a cohort of 19,895 beneficiaries ages >/=65 years diagnosed and excised of colorectal polyps in 1994. Survival analysis was used to compute surveillance and polyp recurrence rates over 5 years. Log-rank test was used for all statistical comparisons.

RESULTS

Median time to first surveillance was 2.6 years. Surveillance rates for 1, 3, and 5 years were 17.6%, 55.8%, and 74.5%, respectively. Twenty-six percent had no surveillance event. Polyp recurrence rates for 1, 3, and 5 years were 10.9%, 38.2%, and 52.6%, respectively. Males and younger patients were more likely to undergo surveillance and showed higher polyp recurrence rates.

CONCLUSIONS

The high likelihood of polyp recurrence underscores the need for continued efforts to promote awareness of and compliance with postpolypectomy surveillance. Efforts to increase surveillance rates among individuals diagnosed with colorectal polyps and making available additional treatment options that may prevent the recurrence of polyps and/or their possible progression to colorectal cancer should help make significant progress in reaching the Healthy People 2010 goal of reducing colorectal cancer deaths by 34% by the year 2010.

Use of colonoscopy for colorectal cancer screening: evidence from the 2000 National Health Interview Survey

BACKGROUND

The use of colonoscopy as a primary screening tool for colorectal cancer is gaining momentum owing to several studies suggesting superior effectiveness and the recent, favorable decision by Medicare to cover all routine screening colonoscopies. This study documents the use of colonoscopy versus other tests to screen for colorectal cancer.

MATERIALS AND METHODS

Data from the 2000 National Health Interview Survey were analyzed. Fecal occult blood test (FOBT), sigmoidoscopy, and colonoscopy done for any reason and for routine screening only were analyzed for those >/=50 years without previously diagnosed colorectal cancer (n = 12,505).

RESULTS

The proportion of the total eligible population receiving any of the recommended tests for all possible reasons and for screening purposes only is 34.6% and 25.1%, respectively. For routine screening purposes, the test most commonly utilized was FOBT (55.6%) followed by colonoscopy (29.1%) and sigmoidoscopy (15.3%). When usage was assessed for all reasons, FOBT was still most commonly utilized (45.8%) followed by colonoscopy (38.7%) and sigmoidoscopy (15.5%). The elderly, non-White males and those with private insurance have a higher probability of receiving colonoscopy than FOBT. Several regional differences exist, including higher probability of undergoing sigmoidoscopy versus colonoscopy in the West.

CONCLUSIONS

Only one fourth (upper limit one third) of the study population complied with colorectal cancer screening recommendations. Nearly one third of the routine screening tests done in 2000 were colonoscopies. This study provides baseline values that can be used to project future colonoscopy demand and identify potential supply barriers.

The impact of urinary urgency and frequency on health-related quality of life in overactive bladder: results from a national community survey

OBJECTIVES

Overactive bladder (OAB) is described as urinary urgency, with and without urge incontinence and usually with frequency and nocturia. Most attention to OAB's impact on health-related quality of life (HRQL), however, has focused on urge incontinence. The objective of this study was to evaluate the burden of OAB, specifically urinary urgency and frequency on HRQL.

METHODS

In the National Overactive Bladder Evaluation Program (NOBLE), a computer-assisted telephone interview survey was conducted to assess the prevalence of OAB in the United States. Based on interview responses, respondents were classified into three groups: continent OAB, incontinent OAB, and controls. To evaluate the HRQL impact of OAB, HRQL questionnaires were mailed to all respondents with OAB and age- and sex-matched controls as a performed nested case-control study. Continuous data were compared using Student's t tests and analysis of variance with post hoc pairwise comparisons; results were adjusted for age, sex, and comorbid conditions. Multivariable regressions were performed to assess the impact of each urinary variable on symptom bother and HRQL.

RESULTS

A total of 919 participants responded to the questionnaires (52% response rate) with a mean age of 54.2 years (SD 16.4 years); 70.4% were female and 85% were white. Continent OAB participants comprised 24.8% of the sample, incontinent OAB 18.3%, and controls 56.9%. In each regression analysis, urinary urge intensity accounted for the greatest variance for increases in symptom bother and decreases in HRQL.

CONCLUSIONS

The experience of urinary urgency has a significant negative effect on HRQL and increases symptom bother, an effect that, in this community sample, is greater than that of incontinence, frequency, or nocturia.

Adherence with colorectal cancer screening guidelines: a review

OBJECTIVE

To review screening rates and factors impacting patient utilization of colorectal cancer screening tests.

METHODS

We searched Medline, CancerLit, and PsycInfo for articles on colorectal cancer screening adherence. US studies on average-risk individuals were reviewed to identify: (1) utilization/adherence rates, (2) predictors of patient adherence, (3) correlation between long-term adherence and type of test selected, (4) predictors of physician recommendation of screening tests, and (5) patterns in the type of test recommended by physicians.

RESULTS

In 2000, only 34% of the US population obtained screening within recommended time frames (fecal occult blood test annually, flexible sigmoidoscopy every 5 years, or colonoscopy every 10 years). Positive attitude toward screening and physician recommendation result in high adherence while fear of finding cancer and the belief that cancer is fatal result in low adherence. Physician specialty impacts the type of test recommended, while perceived lack of patient adherence is not a consistent barrier to recommending screening tests. Matching individuals with their choice of screening test and newer technology, such as virtual colonoscopy, may help increase adherence.

CONCLUSION

Additional studies are required on differences in adherence between tests, whether patient preferences impact adherence, and how the physician-patient relationship can be fostered to increase adherence.

Psychometric evaluation of the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (Fact/GOG-Ntx) questionnaire for patients receiving systemic chemotherapy

The purpose of this study was to validate the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) questionnaire. The FACT/GOG-Ntx is the FACT-G plus an eleven-item subscale (Ntx subscale) that evaluates symptoms and concerns associated specifically with chemotherapy-induced neuropathy. Two groups of women with ovarian cancer completed the FACT/GOG-Ntx: one group with known neurotoxicities and one group of chemotherapy-naive women newly diagnosed with ovarian cancer. Levels of patient neuropathy, severity of toxicity, and patient quality of life from diagnosis of ovarian cancer to 12 months post-diagnosis were assessed. The Ntx subscale significantly differentiated the two groups at baseline and 3- and 6-month follow-ups, demonstrating significantly fewer problems among chemotherapy-naive patients than among patients with known neuropathy. The FACT/GOG-Ntx is a reliable and valid instrument for assessing the impact of neuropathy on health-related quality of life. The Ntx subscale demonstrated sensitivity to meaningful clinical distinctions and change over time.

Properties of polarization evolution in spun fibers

We study the properties of polarization evolution in sinusoidally spun fibers. It is found that, similar to linear birefringent fibers, the evolution of the state of polarization exhibits periodicity, which can be measured by distributed measurement, such as those made with a polarization optical time domain reflectometer. The spatial period is linked with the spin parameters and fiber beat length in a simple equation. In combination with a previous finding, it is shown that the spatial period is uniquely related to spun-fiber polarization mode dispersion. This suggests that distributed fiber polarization mode dispersion can be determined throughthe measurement of the spatial period obtained in a distributed measurement.

Estimated economic costs of overactive bladder in the United States

OBJECTIVES

To estimate the economic costs of overactive bladder (OAB), including community and nursing home residents, and to compare the costs in male versus female and older versus younger populations.

METHODS

The National Overactive Bladder Evaluation Program included a representative telephone survey of 5204 community-dwelling adults 18 years and older in the United States and a follow-up postal survey of all individuals with OAB identified and age and sex-matched controls. The postal survey asked respondents about bladder symptoms, self-care use, treatment use, work loss, and OAB-related health consequences. Survey data estimates were combined with year 2000 average cost data to calculate the cost of OAB in the community. Institutional costs were estimated from the costs of urinary incontinence in nursing homes, limited to only those with urge incontinence or mixed incontinence (urge and stress).

RESULTS

The estimated total economic cost of OAB was 12.02 billion dollars in 2000, with 9.17 and 2.85 billion dollars incurred in the community and institutions, respectively. Community female and male OAB costs totaled 7.37 and 1.79 billion dollars, respectively. The estimated total cost was sensitive to the estimated prevalence of OAB; therefore, we calculated the average cost per community-dwelling person with OAB, which was 267 dollars per year.

CONCLUSIONS

By quantifying the total economic costs of OAB, this study-the first obtained from national survey data-provides an important perspective of this condition in society. The conservative estimates of the total cost of OAB were comparable to those of osteoporosis and gynecologic and breast cancer. Although this provides information on the direct and indirect costs of OAB, quality-of-life issues must be taken into account to gain a better understanding of this condition.

Prevalence and burden of overactive bladder in the United States

CONTEXT

the National Overactive BLadder Evaluation (NOBLE) Program was initiated to better understand the prevalence and burden of overactive bladder in a broad spectrum of the United States population.

OBJECTIVE

to estimate the prevalence of overactive bladder with and without urge incontinence in the US, assess variation in prevalence by sex and other factors, and measure individual burden.

DESIGN

US national telephone survey using a clinically validated interview and a follow-up nested study comparing overactive bladder cases to sex- and age-matched controls.

SETTING

noninstitutionalized US adult population.

PARTICIPANTS

a sample of 5,204 adults >/=18 years of age and representative of the US population by sex, age, and geographical region.

MAIN OUTCOME MEASURES

prevalence of overactive bladder with and without urge incontinence and risk factors for overactive bladder in the US. In the nested case-control study, SF-36, CES-D, and MOS sleep scores were used to assess impact.

RESULTS

the overall prevalence of overactive bladder was similar between men (16.0%) and women (16.9%), but sex-specific prevalence differed substantially by severity of symptoms. In women, prevalence of urge incontinence increased with age from 2.0% to 19% with a marked increase after 44 years of age, and in men, increased with age from 0.3% to 8.9% with a marked increase after 64 years of age. Across all age groups, overactive bladder without urge incontinence was more common in men than in women. Overactive bladder with and without urge incontinence was associated with clinically and significantly lower SF-36 quality-of-life scores, higher CES-D depression scores, and poorer quality of sleep than matched controls.

CONCLUSIONS

the NOBLE studies do not support the commonly held notion that women are considerably more likely than men to have urgency-related bladder control problems. The overall prevalence of overactive bladder does not differ by sex; however, the severity and nature of symptom expression does differ. Sex-specific anatomic differences may increase the probability that overactive bladder is expressed as urge incontinence among women compared with men. Nonetheless, overactive bladder, with and without incontinence, has a clinically significant impact on quality-of-life, quality-of-sleep, and mental health, in both men and women.

Coping strategies and health care-seeking behavior in a US national sample of adults with symptoms suggestive of overactive bladder

BACKGROUND

Although millions of individuals have symptoms suggestive of overactive bladder (OAB), few ever seek or receive medical treatment for their condition.

OBJECTIVE

The purpose of this study was to describe coping strategies and health care-seeking behavior in a community-based sample of adults with symptoms suggestive of OAB.

METHODS

A cross-sectional household telephone survey of an age- and sex-stratified sample of adults was conducted. The survey consisted of general health-related questions as well as questions related to OAB symptoms. A total of 4896 adults completed the interview Respondents were considered to have OAB if they reported > or = 1 symptom of urinary urgency, frequency, or urge incontinence. A follow-up questionnaire was then mailed to a subsample of the telephone interview respondents. The mailed questionnaire contained questions related to type and severity of OAB symptoms, coping strategies, medical care/treatment, feelings/beliefs about OAB, and quality of life. Half of the phone respondents with urinary incontinence (n = 638) and a random sample of all other phone respondents received the mailed questionnaire (n = 873); 1,034 questionnaires were returned.

RESULTS

Of the respondents with OAB, 69.6% tried > or = 1 nonmedical coping strategy. Respondents with incontinent OAB were significantly more likely than those with continent OAB or those with no OAB (controls) to use nonmedical coping strategies (incontinent OAB, 76.1%; continent OAB, 59.0%; controls, 31.9%; P < 0.001). Fewer than half of the respondents with OAB (43.5%) had spoken with a provider about OAB in the previous 12 months. Medical consultation was associated with sex, type and severity of OAB, number of nonmedical coping strategies tried, number of OAB information sources consulted, inclination to try new OAB medications, and feelings/beliefs about OAB. In 90% of patient-provider discussions about OAB, the patient initiated the topic.

CONCLUSIONS

Individuals manage symptoms suggestive of OAB primarily by using nonmedical coping strategies rather than consulting health care providers. Results of this study support the need for improved clinical recognition of OAB and increased patient-provider communication about this condition.

Health-related quality of life among adults with symptoms of overactive bladder: results from a U.S. community-based survey

OBJECTIVES

To assess, by means of a survey, the impact of the symptoms of overactive bladder (urinary frequency, urgency, and urge incontinence) on the quality of life in a community-based sample of the U.S. population.

METHODS

A telephone survey was conducted in the United States among an age and sex-stratified sample of 4896 noninstitutionalized adults 18 years of age and older. From the responses to the telephone survey, a total of 483 individuals with symptoms of overactive bladder and 191 controls completed a mailed follow-up questionnaire to assess their quality of life using the Medical Outcomes Study Short-Form 20.

RESULTS

After adjustment for age, sex, and the use of medical care, the greatest differences in the quality-of-life scores between the patients with incontinent overactive bladders and the controls were in the health perception (17.6 points; P <0.001) and role functioning (13.0 points; P <0.001) scales. Those with an overactive bladder with the symptoms of frequency or urgency, or both, but without incontinence, also had significantly lower scores than did the controls in mental health (P = 0.026), health perception (P = 0.01), and bodily pain (P = 0.016).

CONCLUSIONS

These data indicate that individuals with an overactive bladder experience decrements in their quality of life relative to community controls. An important new finding from this study is that individuals with an overactive bladder, even without demonstrable urine loss, also have a poorer quality of life than that of controls.

The effect of rofecoxib on the pharmacodynamics and pharmcokinetics of warfarin

OBJECTIVE

The objective of this study was to examine the effect of 3 doses of rofecoxib (12.5, 25, and 50 mg) on the pharmacodynamics and pharmacokinetics of warfarin.

METHODS

Two single-dose (12.5 or 50 mg of rofecoxib with 25 mg or 30 mg of oral warfarin, respectively, on day 7 of each period) trials (N = 12 men) and 1 steady-state warfarin trial (25 mg rofecoxib; N = 15, 13 men and 2 women) were completed as two-period, randomized, balanced, crossover, double-blind designs. The prothrombin time international normalized ratio (INR) and S(-) and R(+) warfarin enantiomers were assessed during 144 hours after the single warfarin doses. In the steady-state warfarin trial, after the attainment of a stable INR (1.4-1.7), the stable warfarin dose was co-administered with rofecoxib (25 mg) and placebo over two 21-day periods. After the dose of warfarin on day 21, INR and S(-) and R(+) warfarin were assessed during 24 hours.

RESULTS

Compared with placebo, rofecoxib slightly increased the INR by approximately 5% (90% confidence interval on the geometric ratio, 1.03, 1.08) and 11% (1.04, 1.19) for the two single-dose warfarin trials with 12.5 and 50 mg of rofecoxib, respectively. In the steady-state warfarin study with 25 mg of rofecoxib, the INR was increased by 8% (1.02, 1.15). Rofecoxib had no significant effect (versus placebo) on the pharmacokinetics of S(-) warfarin. However, in the 3 studies, treatment with 12.5, 25, and 50 mg of rofecoxib was associated with a 27%, 38%, and 40% increase in the area under the plasma concentration-time curve of the biologically less active R(+) warfarin.

CONCLUSIONS

Rofecoxib increased plasma concentrations of the biologically less active R(+) warfarin, which accounted for a small increase in INR. The approximately 8% increase in INR at steady state with warfarin co-administered with 25 mg of rofecoxib is not likely to be clinically important in most patients taking warfarin. However, standard monitoring of INR values should be conducted when therapy with rofecoxib is initiated or changed, particularly in the first few days, for patients receiving warfarin.

Absence of pharmacokinetic interaction between orally co-administered naproxen sodium and diphenhydramine hydrochloride

The potential for a pharmacokinetic interaction between naproxen and diphenhydramine was examined in a randomized three-way crossover design with a 1-week washout between dosing. Single oral doses of 220 mg of naproxen sodium and 50 mg of diphenhydramine hydrochloride were given separately and together to 30 healthy male and female subjects. Heparinized blood samples obtained for 48 h postdose were assayed for plasma naproxen and diphenhydramine concentrations using validated high-performance liquid chromatography (HPLC) and gas chromatography (GC) assay methods, respectively. The area under the plasma concentration-time curve (AUC), maximum plasma concentrations (C(max)), time of C(max) (T(max)) and terminal exponential half-life (t(1/2,z)), were analysed for significant treatment differences by analysis of variance (ANOVA). Based on absence of significant treatment effects on AUC and C(max), single-dose oral co-administration of 220 mg of naproxen sodium with 50 mg of diphenhydramine hydrochloride does not alter the pharmacokinetics of either naproxen or diphenhydramine. Significant treatment differences seen for naproxen T(max) (0.3 h, males only) and diphenhydramine t(1/2,z) (0.8 h, females only) were minor and are unlikely to have therapeutic consequences. Thus, efficacy and safety of concomitant naproxen and diphenhydramine should not be altered due to a pharmacokinetic interaction.

Celecoxib, a specific COX-2 inhibitor, has no significant effect on methotrexate pharmacokinetics in patients with rheumatoid arthritis

OBJECTIVE

To determine the effects of celecoxib, a specific inhibitor of cyclooxygenase 2 (COX-2) on the renal clearance and plasma pharmacokinetic profile of stable methotrexate (MTX) doses in patients with rheumatoid arthritis (RA).

METHODS

Fourteen adult female patients with RA taking a stable weekly dose of MTX (5 to 15 mg/wk) for a minimum of 3 months were randomized to receive concomitantly either celecoxib (200 mg BID) or placebo for a period of 7 days in a single blind, 2 period crossover study of MTX pharmacokinetics and renal clearance.

RESULTS

The plasma pharmacokinetic profile of MTX did not change significantly when celecoxib or a placebo was coadministered. The mean renal clearance of MTX alone, 7.98+/-2.18 l/h, was virtually unchanged by coadministration of celecoxib (7.94+/-1.61 l/h) or placebo (7.97+/-1.19 l/h).

CONCLUSION

Celecoxib has no significant effect on the pharmacokinetics or renal clearance of MTX in patients with RA, although these results should be confirmed in prospective studies of elderly and renally impaired patients.

Pharmacokinetics, safety, and tolerability of single intravenous infusions of an adenosine agonist, AMP 579, in healthy male volunteers

The pharmacokinetics of an adenosine agonist, AMP 579, following intravenous administration were evaluated. Single AMP 579 doses of 20 to 150 micrograms/kg were infused intravenously over 6 hours using a constant-rate or two-step rate of infusion to healthy male volunteers. Plasma and urine samples were collected for measurement of AMP 579 concentration using a validated HPLC assay. An assessment of safety and tolerability was also performed. Based on a noncompartmental method of analysis, the pharmacokinetics of AMP 579 were characterized by rapid systemic clearance (0.77 to 0.85 L/h/kg), a moderate steady-state volume of distribution (0.80 to 0.94 L/kg), and a short terminal elimination half-life (0.84 to 1.13 h). AMP 579 exhibited dose (infusion rate)-proportional pharmacokinetics over the dose range. In addition, little or no unchanged AMP 579 was found in the urine. The primary cardiovascular pharmacodynamic response that was observed was a dose-related increase in mean ventricular heart rate. Fifteen minutes prior to the end of the infusion, volunteers administered the highest dose (150 micrograms/kg) exhibited a mean (range) 59% (36%-69%) increase in heart rate as compared to a mean (range) 18% (0%-73%) increase for the placebo group. No clinically relevant changes in the systolic or diastolic blood pressure were observed. The information obtained in this study should allow the design of AMP 579 dosage regimens that would maximize plasma AMP 579 concentrations and minimize the incidence of adverse events.

Effects of food on the pharmacokinetics of sparfloxacin

Sparfloxacin, a fluoroquinolone with a broad antimicrobial spectrum and long elimination half-life, is indicated for the treatment of community-acquired pneumonia and acute bacterial exacerbations of chronic bronchitis in adult patients. The present study was undertaken to determine the effects of skim milk and a high-fat breakfast without milk on the single-dose pharmacokinetic characteristics of this antibiotic. The pharmacokinetics of a single 200-mg dose of sparfloxacin were assessed in a 3-way crossover study that included 23 healthy male volunteers who had fasted, had ingested 240 mL of skim milk, or had consumed a standard high-fat breakfast. The subjects' mean age and weight were 26.5 years and 73.2 kg, respectively; 17 were white, 5 Hispanic, and 1 black. Neither skim milk nor the high-fat breakfast had a statistically significant effect on sparfloxacin absorption, as reflected in the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve (AUC). Ninety percent confidence limits for logarithmically transformed AUC from time zero to infinity and Cmax were within the 80% to 125% range, demonstrating that the rate and extent of sparfloxacin absorption with skim milk or a high-fat breakfast were not different from those under fasted conditions. As indicated by an increase in the time to Cmax from 3.6 to 5.4 hours, the high-fat breakfast slightly delayed the onset of sparfloxacin absorption. Skim milk and the high-fat breakfast did not significantly affect the elimination kinetics of sparfloxacin. Sparfloxacin was well tolerated in all 3 treatment groups. Despite the apparent delay in the onset of absorption, the bioavailability of sparfloxacin in the healthy male subjects in this study population was not affected by concomitant administration with skim milk or a high-fat meal. Accordingly, the results suggest that sparfloxacin can be administered without regard to the ingestion of milk or meals.

Pharmacokinetic interaction of sparfloxacin and digoxin

Sparfloxacin, a broad-spectrum, oral fluoroquinolone antimicrobial agent, has a long elimination half-life that permits once-daily administration. Antibiotics may increase the oral bioavailability of digoxin, leading to increases in its plasma concentration. Since patients treated with sparfloxacin may be receiving concurrent treatment with digoxin, the possibility of an interaction between sparfloxacin and digoxin was examined in a double-masked, placebo-controlled, multiple-dose, two-way crossover study in 24 healthy male volunteers between 20 and 49 years of age. All subjects were given digoxin 0.3 mg once daily throughout the 20-day study. Sparfloxacin (or placebo) was given as a 400-mg loading dose on day 1, followed by single 200-mg daily doses for 9 days, with crossover to the alternate treatment on days 11 through 20. Plasma levels of digoxin were analyzed by validated radioimmunoassay, and plasma levels of sparfloxacin were analyzed by validated high-performance liquid chromatography. Concomitant administration of sparfloxacin and digoxin was generally well tolerated. Mean values for steady-state area under the concentration-time curve over 24 hours for the 2 treatments were virtually identical: 28.4 ng/h per mL(-1) for digoxin administered with placebo and 28.9 ng/h per mL(-1) for digoxin administered concomitantly with sparfloxacin. Mean steady-state maximum plasma concentrations were 3.91 and 3.59 ng/mL for digoxin with placebo and digoxin with sparfloxacin, respectively. Mean steady-state trough plasma digoxin concentrations for the 2 treatments were 0.87 and 0.89 ng/mL, respectively. Mean times to steady-state maximum plasma concentrations were identical at 0.89 hours for both treatments. Mean steady-state oral clearance was 10.6 L/h for digoxin alone and 10.4 L/h for digoxin with sparfloxacin. Thus administration of sparfloxacin in combination with digoxin did not alter the pharmacokinetics of digoxin in healthy male volunteers aged 20 to 49 years. Steady-state plasma sparfloxacin concentrations were consistent with those obtained in other multiple-dose phase I studies, suggesting that digoxin does not alter the steady-state pharmacokinetics of sparfloxacin.

Effect of montelukast on single-dose theophylline pharmacokinetics

The effect of montelukast (MK-0476), a cysteinyl leukotriene receptor antagonist in development for treatment of asthma, on single-dose theophylline plasma concentrations was studied in three separate clinical trials. Montelukast was evaluated at 10 mg once daily (the clinical dosage), 200 mg once daily, and 600 mg (200 mg three times daily). At the clinical dosage, montelukast did not change single-dose theophylline plasma concentration in a clinically important manner. The geometric mean ratios for theophylline area under the plasma concentration versus time curve (AUC0-->infinity ) (0.92) and maximal plasma concentration (Cmax ) (1.04) were well within the predefined and generally accepted bioequivalence range of 0.80 and 1.25. Montelukast decreased theophylline Cmax by 12% and 10%, AUC0-->infinity by 43% and 44%, and elimination half-time by 44% and 39% at 200 mg/d (oral and intravenous, respectively), and at 600 mg/d, montelukast decreased theophylline Cmax by 25%, AUC0-->infinity by 66%, and elimination half-time by 63%. These results show that montelukast at the clinical dosage did not change theophylline pharmacokinetics in a clinically important manner, but at 20- to 60-fold higher dosages, montelukast significantly reduced the theophylline pharmacokinetics parameters; an apparent dosage dependence is suggested.

Effect of infusion rate on the pharmacokinetics and tolerance of intravenous dolasetron mesylate

OBJECTIVE

To evaluate the safety, tolerance, and pharmacokinetics of dolasetron mesylate and its active metabolite hydrodolasetron when dolasetron mesylate was administered intravenously at increasing infusion rates.

DESIGN

A double-blind, placebo-controlled, parallel-group study.

METHODS

Forty-nine healthy nonsmoking male volunteers were randomly assigned to receive intravenous doses of dolasetron mesylate 100 mg or placebo. Three groups of 16 subjects each (12 dolasetron mesylate, 4 placebo) received escalating infusion rates (50, 100, then 200 mg/min). Physical examinations, vital signs, laboratory tests, and adverse events were recorded before and after administration of the study drug. Serial blood samples and 12-lead electrocardiogram measurements were obtained for 24 hours after the infusion. Plasma samples were analyzed for dolasetron and hydrodolasetron.

RESULTS

Dolasetron mesylate was well tolerated, with no apparent differences in vital signs or adverse event profiles among the different rates of infusion. In general, the pharmacokinetics of dolasetron and hydrodolasetron were superimposable among the three infusion rate groups. Plasma dolasetron concentrations declined rapidly in all three infusion rate groups, with mean elimination half-life (t1/2) of less than 10 minutes. The reduced metabolite hydrodolasetron, which accounts for most pharmacologic activity, formed rapidly, with maximum concentrations occurring between 0.4 and 0.5 hours and disappeared with a mean t1/2 of 8-9 hours. The correlation coefficients of least-squares regression analysis between the pharmacokinetic parameters and the infusion rate of dolasetron were less than 0.083 and the slopes were not significantly different from 0, suggesting that none of the hydrodolasetron pharmacokinetic parameters were affected by rate of infusion.

CONCLUSIONS

The intravenous administration of dolasetron 100 mg over 0.5-2 minutes did not significantly alter the pharmacokinetic profiles of either dolasetron or hydrodolasetron. In addition, the safety profile of dolasetron did not change with increasing rate of infusion. Therefore, the rate of infusion of dolasetron mesylate appears to have no pharmacokinetic or clinical implications when assessed over a 0.5-2-minute time period.

Safe coadministration of terbinafine and terfenadine: a placebo-controlled crossover study of pharmacokinetic and pharmacodynamic interactions in healthy volunteers

The pharmacokinetic and pharmacodynamic interactions of terbinafine (Lamisil) and terfenadine (Seldane) were assessed in 26 healthy volunteers randomized to receive either terbinafine (250 mg tablet) or its placebo (terbinafine placebo), which were administered in a double-blind manner once daily for 18 days. On days 12 through 18, terfenadine was coadministered (60 mg twice daily, unblinded). Pharmacokinetic profiles were obtained for terbinafine and its desmethyl metabolite on day 11 (in the absence of terfenadine), day 12, and day 18. Terfenadine and terfenadine acid metabolite levels were also assayed on days 12 and 18. After a 4-week washout period, subjects were crossed over to the alternate treatment (terbinafine or terbinafine placebo). Pharmacodynamic measures were electrocardiographic (ECG) rhythm abnormalities, corrected QT interval (QTc), and plasma ALT levels. Terfenadine levels were evaluated; however, only eight of 1502 samples assayed were above the limit of quantitation. No effect of terbinafine administration on pharmacokinetic parameters for the terfenadine acid metabolite was observed, except for a decrease of approximately 20% in through terbinafine concentrations (C0hr; p < 0.05) on the last day of terfenadine plus terbinafine coadministration. Pharmacokinetic parameters for terbinafine were unchanged on the first day of terfenadine coadministration, and only small increases in area under the plasma concentration versus time curve from 0 to 24 hours and peak plasma concentrations (16.1%[p < 0.01] and 6.63% [p < 0.05]) were observed on the last day of terfenadine and terbinafine coadministration. Values for C0hr were also about 20% to 25% higher (p < 0.05). Steady-state levels of the terfenadine acid metabolite were achieved after 2 days of terfenadine coadministration, and steady-state levels of terbinafine and its desmethyl metabolite were achieved after 14 days of terbinafine administration. The incidence of ECG rhythm abnormalities was not significantly higher in any treatment group; however, the incidence of prolongation of QTc > 10% above baseline was significantly higher in the groups treated with terfenadine. No QTc prolongation occurred in the absence of terfenadine treatment. Both terbinafine and terfenadine were well tolerated when coadministered during this study, as indicated by the low incidence of complaints, abnormalities, and adverse events. The results of this study indicate that terbinafine and terfenadine can be safely coadministered.

Multiple-dose, placebo-controlled, phase I study of oral dolasetron

STUDY OBJECTIVES

To evaluate the safety, tolerability, and pharmacokinetics of increasing dose levels of oral dolasetron mesylate, a new 5-HT3 antagonist.

DESIGN

Double-blind, placebo-controlled, dose-ranging phase I study.

SETTING

A clinical research center.

PATIENTS

Forty healthy male volunteers.

INTERVENTIONS

Eight subjects at each dose level were randomized in a ratio of 3:1 to receive either dolasetron mesylate 25, 50, 100, 150, or 200 mg in a single oral dose on days 1 and 9, and twice/day on days 2-8, or placebo for 9 days.

MEASUREMENTS AND MAIN RESULTS

Dolasetron was well tolerated at all dose levels. The adverse event rates for dolasetron- and placebo-treated subjects who experienced at least one adverse event were 80% and 50%, respectively. Most frequently reported by subjects receiving dolasetron were headache, constipation, flatulence, and lightheadedness. They generally were mild, and none was severe. No dose-response relationship was apparent for any adverse event. There were no clinically significant changes in mean laboratory values or vital signs. Asymptomatic treatment-related electrocardiographic changes were consistent with the drug's electrophysiologic properties. These changes have been well characterized and have thus far been clinically unimportant. Pharmacokinetics of the reduced metabolite were dose independent, and multiple-dose exposure of this metabolite can be predicted from its single-dose values.

CONCLUSION

Oral dolasetron mesylate was well tolerated when administered in doses up to 200 mg/day for 9 days in healthy volunteers.

A double-blind, placebo-controlled, dose-ranging safety evaluation of single-dose intravenous dolasetron in healthy male volunteers

The safety and tolerability of dolasetron mesylate, a potent and selective 5-HT3 receptor antagonist, were evaluated after single intravenous doses in healthy male volunteers. In this double-blind, placebo-controlled, randomized, phase I study, 80 subjects received either placebo or dolasetron in escalating doses (0.6 to 5.0 mg/k). Subjects were monitored for adverse events, vital sign and laboratory alterations, and changes in electrocardiographic (ECG) intervals and electroencephalographic (EEG) patterns. Overall, the percentage of subjects reporting adverse events was similar in those receiving dolasetron (44/64; 68.8%) or placebo (10/16; 62.5%); most adverse events were mild in severity. Subjects receiving dolasetron reported a higher incidence of central nervous system (headache and dizziness/lightheadedness), gastrointestinal (increased appetite and nausea), and visual adverse events and taste alterations. No clinically significant changes in laboratory variables were observed. Transient and asymptomatic ECG changes (small mean increases in PR interval and QRS complex duration versus baseline) were noted in several subjects at 1 to 2 hours after infusion at doses > or = 3.0 mg/kg. Transient, mild blood pressure decreases were observed in five subjects, including one on placebo. Dolastron mesylate was well tolerated in single intravenous doses up to 5.0 mg/kg in healthy male volunteers. Clinical studies of the drug are ongoing for antiemetic indications.

Effect of the acyl-CoA:cholesterol acyltransferase inhibitor DuP 128 on cholesterol absorption and serum cholesterol in humans

Intestinal cholesterol esterification by the enzyme acyl-CoA:cholesterol acyltransferase (ACAT) is a presumed prerequisite for cholesterol absorption. We evaluated the effect of a potent, poorly absorbed ACAT inhibitor (DuP 128: N'-(2,4-difluorophenyl)-N-[5-(4,5-diphenyl-1H-imidazol-2-ylthio)pe ntyl]- N-heptylurea) on cholesterol absorption in a randomized trial. Thirty subjects received DuP 128 for 7 weeks, 10 each at 900 mg per day, 1800 mg per day, and 3600 mg per day; six subjects received placebo; and nine subjects received 1 gm neomycin twice a day. Cholesterol absorption determinations used a continuous dual isotope 14C-cholesterol and 3H-beta sitosterol method. DuP 128 (pooled doses) induced at 14.4% +/- 11.4% reduction in cholesterol absorption (p < 0.05 versus placebo): 17.6% +/- 8.4% at 900 mg, 9.1% +/- 11.4% at 1800 mg, and 17.1% +/- 12.9% at 3600 mg. Neomycin induced a 26.4% +/- 10.7% reduction (p < 0.01). After 6 weeks, neomycin reduced serum total and low-density lipoprotein cholesterol by 22.4% +/- 9.2% and 24.0% +/- 11.6%, respectively (p < 0.01 versus placebo). DuP 128 induced reductions of 3.9% +/- 11% (difference not significant) and 4.95% +/- 14.3% (p = 0.05). ACAT inhibitors limit cholesterol absorption in humans; however, the magnitude of the effect, as exemplified by DuP 128, is small.

Bioequivalence of verapamil hydrochloride extended-release pellet-filled capsules when opened and sprinkled on food and when swallowed intact

A study was performed to determine whether verapamil hydrochloride administered in extended-release pellet-filled capsules is bioequivalent to the same formulation administered by sprinkling the contents of the capsules onto food. Thirty-two healthy subjects participated in the randomized, two-way crossover study. In treatment A, the subjects swallowed the contents of a verapamil hydrochloride extended-release pellet-filled capsule, 240 mg, that had been sprinkled on applesauce. In treatment B, the subjects swallowed the same type of capsule intact. Blood samples were drawn at baseline, every hour for 10 hours, and at 12, 15, 24, 30, 36, and 48 hours after each dose administration. The plasma was analyzed for verapamil and norverapamil by high-performance liquid chromatography. The following calculations were performed: AUC0-48, AUC0-infinity, Cmax, tmax, and k. Results for the two treatments were compared by analysis of variance. There were no significant differences between the AUC0-48, AUC0-infinity, Cmax, tmax, and k for the two methods of dose administration. For verapamil the differences for all variables were less than 5%, and for norverapamil the differences were less than 4% for all variables except tmax (9.5%). The 90% confidence intervals were within acceptable limits for all variables except the norverapamil tmax comparison. Sprinkling the contents of extended-release pellet-filled capsules onto food provides verapamil hydrochloride that is bioequivalent to that obtained from the intact capsules.

Comparison of the pharmacokinetic profiles of two oral controlled-release morphine formulations in healthy young adults

The pharmacokinetic profiles of two oral controlled-release morphine formulations, MS Contin tablets and Roxanol SR tablets, were compared to evaluate their bioequivalence. In a sequential, crossover study, 18 healthy young male volunteers received single 60-mg doses (two 30-mg tablets) of each formulation and provided 15 serial blood samples over 24 hours, which were assayed to determine their morphine concentrations by high-performance liquid chromatography. Analysis of variance revealed significant differences between the treatments for maximum plasma concentration (P less than 0.001), area under the plasma concentration curve from zero to 12 hours (P less than 0.01), and apparent elimination half-life (P less than 0.001). No significant differences were found for time required to reach maximum plasma concentration and area under the plasma concentration-time curve from zero to 24 hours. The results show that the two morphine preparations are not bioequivalent.

Pharmacokinetics and safety of lomefloxacin following multiple doses

This was a randomized, double-blind, placebo-controlled study comparing the safety and tolerance of 400 mg lomefloxacin, given orally twice daily, to that of placebo administered to eight and four subjects, respectively, for 2 wk. This dose, interval, and duration of dosing were chosen to be identical to the highest anticipated clinical dose for the longest anticipated clinical duration. Subject assessments included ophthalmological examinations performed prior to the study, at midstudy, and after the dosing. No clinically significant differences from baseline were observed for any test result. Analysis of trough plasma concentrations, CMIN, showed that steady state was achieved on Day 4 (Fig. 2). At steady-state, mean plasma concentrations of lomefloxacin ranged from a maximum of 4.86 micrograms/ml to a minimum of 1.47 micrograms/ml. Mean time to maximum plasma concentration on Day 14 was 1.23 hr in the morning and 3.81 hr in the evening. Plasma half-life was approximately 8 hr. Lomefloxacin was well tolerated at 400 mg administered twice daily for 2 wk; plasma concentrations were maintained at a level that is above the MIC of most clinically significant isolates.

Oral antimicrobial therapy for adults with osteomyelitis or septic arthritis

We conducted a retrospective review of 21 adult patients with osteomyelitis and septic arthritis who were treated with high doses of oral antimicrobial agents, usually after an initial course of intravenous therapy. The mean duration of parenteral and oral therapy was 3.6 days and 43.0 days, respectively. Absorption of oral antibiotics was assessed by determining the trough serum bactericidal titers for the infecting organism; whenever feasible, the dosages were adjusted to achieve trough titers greater than or equal to 1:8. The follow-up period ranged from six to 66 months (mean, 42.4 months). Eighteen of 21 patients had no clinical signs of recurrence after initial therapy. One patient with an infected joint prosthesis developed recurrent infection, and two patients had recurrences accompanied by sequestra. The mean duration of hospitalization was 13.4 days, and the mean duration of outpatient treatment was 31.9 days.

Blind nasal intubation in an awake patient for caesarian section

Failure to intubate the trachea continues to claim the lives of women undergoing caesarian section. Obstetric anaesthetists have been advised to desist from prolonged attempts to intubate, and to provide either inhalational anaesthesia via a face mask, or regional anaesthesia. A case is described in which neither of these options was considered appropriate.