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Biomedical subjects

K A Pappa

Publications and source records attributed to K A Pappa.

12 recordsLinked to original sources
PubMed2006

A prospective, 96-week study of the impact of Trizivir, Combivir/nelfinavir, and lamivudine/stavudine/nelfinavir on lipids, metabolic parameters and efficacy in antiretroviral-naive patients: effect of sex and ethnicity.

OBJECTIVES: To compare the lipid and metabolic effects, efficacy, and safety of twice-daily regimens of Trizivir (abacavir 300 mg/lamivudine 150 mg/zidovudine 300 mg triple nucleoside tablet; TZV), Combivir (lamivudine 150 mg/zidovudine 300 mg combination tablet; COM)+nelfinavir (NFV), and stavudine (d4 T)+lamivudine (3TC)+NFV. STUDY DESIGN: An international, phase 4, open-label, parallel-group, 34-centre study was conducted in 254 non-diabetic, antiretroviral-naive, HIV-infected out-patients with an HIV-1 RNA level of >1000 HIV-1 RNA copies/mL and < or =200,000 copies/mL and a CD4 cell count of >50 cells/microL. METHODS: Patients were randomized 1 : 1 : 1 to TZV twice daily (n = 85), COM/NFV 1250 mg twice daily (n = 88), or d4T 40 mg+3TC 150 mg+NFV 1250 mg twice daily (n = 81) for 96 weeks. Treatments were compared using analysis of covariance (ANCOVA) with regard to changes from baseline in fasting lipids in the total population and in sex and ethnic subgroups. The proportions of patients achieving HIV-1 RNA <50 and <400 copies/mL were compared using a 95% confidence interval (CI) on the difference between proportions. RESULTS: The study population was diverse (50% female, 40% black and 37% Hispanic). Mean baseline low-density lipoprotein (LDL) cholesterol was 99 mg/dL, HIV-1 RNA was 4.43 log10 copies/mL and CD4 cell count was 355 cells/microL. At week 96, fasting LDL cholesterol changed minimally in the TZV group [least square mean (LSM) change from baseline, -8 mg/dL], but increased with d4T/3TC/NFV and COM/NFV (+29 and +19 mg/dL, respectively; P < 0.001 versus TZV). Week 96 LDL-cholesterol levels were significantly lower in the TZV group than in the other two treatment groups in women and men and lower than in the d4T/3TC/NFV group in Hispanic and black patients. In black patients, the week-96 LSM change from baseline in LDL cholesterol was significantly less with TZV than with d4T/3TC/NFV (+1 vs+39 mg/dL; P = 0.003). Total cholesterol >200 mg/dL occurred in a smaller proportion of patients receiving TZV (30%) compared with COM/NFV (50%) or d4T/3TC/NFV (60%; P = 0.005 vs TZV). High-density lipoprotein (HDL) cholesterol did not change markedly with any treatment. Although triglycerides increased, they changed least in women and Hispanic patients receiving TZV. Virological and CD4 responses to the treatments were similar in the total population and in the subgroups. Diarrhoea was reported more often in the NFV arms and nausea in the ZDV arms. CONCLUSIONS: Over 96 weeks, TZV twice daily has significantly less effect on LDL cholesterol than COM/NFV or d4T/3TC/NFV twice daily, especially in women and black patients, and is associated with similar virological and CD4 responses.

Black or African American↗
PubMed1999

A double-blind, placebo-controlled study of the efficacy and safety of non-prescription ranitidine 75 mg in the prevention of meal-induced heartburn.

BACKGROUND: Ranitidine 75 mg (Zantac 75) has been shown to be effective for the treatment of pre-existing heartburn symptoms. AIM: To compare the efficacy of dosing ranitidine 75 mg or placebo 30 min prior to a proven heartburn-provoking meal in completely preventing or reducing subsequent heartburn symptoms. METHODS: A randomized, double-blind, parallel methodology was used at nine investigative centres. Following a screening visit, patients ate a standard test meal consisting of chili, chips and a soft drink on two occasions. On the first occasion, patients received single-blind placebo 30 min before the meal. This meal was used to qualify patients and to ensure the onset of a minimum level of heartburn. Patients who qualified were randomized (n = 284) to receive double-blind ranitidine 75 mg or placebo 30 min before a second test meal administered 4-14 days later at the treatment visit. Patients recorded whether heartburn was present and rated heartburn severity by completing visual analogue scales at 15-min intervals over the 4. 5 h meal evaluation periods. RESULTS: Statistically significant differences favouring ranitidine 75 mg were determined for complete prevention of heartburn (P < 0.006), heartburn severity area under the curve (P < 0.001), a clinical success end-point (P < 0.001), and all other end-points (P < 0.001). CONCLUSIONS: These data clearly demonstrate that ranitidine 75 mg is effective in completely preventing or decreasing heartburn when administered 30 min prior to a provocative meal.

Adult↗
PubMed1999

An evaluation of increasing doses of ranitidine for treatment of heartburn.

BACKGROUND: This was a randomized, double-blind, placebo-controlled, multicentre, parallel group, dose-ranging trial of ranitidine tablets for relief of episodic heartburn. Adult out-patients who reported heartburn relieved by antacids at least seven times per week were eligible. METHODS: Patients who successfully completed a 1-week single-blind placebo run-in phase and who did not achieve adequate relief in more than 50% of heartburn episodes were randomized to a 1-week, double-blind treatment phase during which they received ranitidine doses of 25, 75 or 125 mg, or placebo. RESULTS: Of 577 patients randomized, 566 had at least one evaluable heartburn episode and were included in the intention-to-treat analysis. All three ranitidine doses were statistically significantly superior to placebo in providing overall episodic heartburn relief for the first episode (P < 0.002), last episode (P</=0.004), and all episodes combined (P < 0.001). The ranitidine 75 mg and 125 mg doses provided sustained relief (relief within 60 min of dosing that lasted throughout the 4-h evaluation period) to a greater proportion of patients for each individual episode (43-56% for 75 mg and 42-57% for 125 mg) than the ranitidine 25 mg dose (35-50%) or placebo (21-29%). The incidence of adverse events was similar in all treatment groups. CONCLUSIONS: All three ranitidine doses (125, 75 and 25 mg) are safe and superior to placebo in providing adequate relief for heartburn. Ranitidine's onset of relief was progressive and clearly present by 30 min as shown by statistically significant differences for the 75 mg dose when compared to placebo. Similarly, patients treated with ranitidine 75 mg and 125 mg consumed statistically fewer rescue antacids than placebo-treated patients for the first episode. All three doses were well tolerated, with adverse event profiles similar to those of placebo.

Adult↗
PubMed1999

Low-dose ranitidine for the relief of heartburn.

BACKGROUND: Approximately 30% of adults in the USA suffer from heartburn or related symptoms monthly; more than 20% of these sufferers experience heartburn at least once per day. Although many rely on self-medication with antacids for the relief of their symptoms, treatments that decrease gastric volume as well as increase the pH of refluxed material should be more effective in relieving heartburn. AIM: To compare the safety and efficacy of low-dose regimens of ranitidine for the relief of heartburn. METHODS: Adults with at least a 3-month history of heartburn were eligible for this randomized, double-blind, parallel group, multicentre dose-ranging study. Following a 1-week open-label run-in phase to document baseline heartburn frequency, subjects were randomized to receive treatment with one tablet of either ranitidine 75 mg (n = 491), ranitidine 25 mg (n = 504), or placebo (n = 494), to be taken as needed up to four times daily for 2 weeks for the relief of heartburn. RESULTS: The ranitidine 75 mg regimen was clinically (> 10 percentage points) and statistically (P < 0.05) significantly more effective than placebo for all measured efficacy end-points in relieving heartburn and reducing antacid consumption. In addition, the ranitidine 75 mg regimen was superior to placebo in providing heartburn relief within 30 min of dosing that lasted for up to 12 h. Ranitidine 25 mg was observed to be statistically superior (P < 0.05) but not clinically different from placebo, as defined a priori, in providing heartburn relief. All treatments were well tolerated and adverse events occurred no more frequently with the ranitidine regimens than with placebo. CONCLUSIONS: Ranitidine 75 mg provides prompt relief of heartburn that lasts for up to 12 h and has a safety profile comparable to that of placebo.

Adolescent↗
PubMed1994

Single-dose cefuroxime versus multiple-dose cefazolin as prophylactic therapy for high-risk cholecystectomy.

The ideal regimen for the prevention of postoperative infections occurring after elective cholecystectomy has been widely debated. This double-blind, randomized study was conducted to compare the effectiveness and safety of cefuroxime with that of cefazolin in 295 patients undergoing elective cholecystectomy who were considered to be at high risk for postoperative infection. Patients were randomly assigned to receive either a single 1.5 gram dose of cefuroxime plus three doses of placebo, or four 1 gram doses of cefazolin. Each regimen was begun 30 to 60 minutes preoperatively and repeated every six hours for three doses postoperatively. Patients were evaluated during the hospitalization period and again at 30 days. All postoperative infections, including remote infections, were included in the definition of failure. Bacteriologic success rates were 95.5 percent in the cefuroxime group and 98.2 percent in the cefazolin group (p > 0.05). Corresponding clinical success rates were 91.4 and 94.9 percent (p > 0.05), respectively. There was no association between intraoperative bile cultures and the risk of failure or the type of microorganism isolated from postoperative infections. Both regimens were well-tolerated. In view of the additional costs and time associated with preparation and administration of multiple doses, a single preoperative 1.5 gram dose of cefuroxime may be a cost-effective alternative to four 1 gram doses of cefazolin in patients undergoing elective cholecystectomy who are at high risk for postoperative infection.

Cefazolin↗
PubMed1990

Pharmacokinetics of oral and transdermal triprolidine.

In this open, nonrandomized, three-way crossover study, six healthy male volunteers received single doses of triprolidine (TPL) hydrochloride syrup orally (2.5 mg) and wore transdermal TPL patches (5 mg and 10 mg doses) to compare the pharmacokinetic profiles and dose tolerance of the two formulations. A washout period of at least 1 week was scheduled between the three dosing periods. Blood samples were collected at defined times, and plasma concentrations were determined using a radioimmunoassay. Maximum plasma drug concentration (Cmax) decreased from 5.6 +/- 2.9 ng/mL (mean +/- SD) with oral dosing to 2.0 +/- 1.0 ng/mL and 4.2 +/- 2.0 ng/mL following 5 mg and 10 mg transdermal doses, respectively. Time to reach peak concentration (tmax) increased from 2.0 +/- 1.2 hours with oral dosing to 12.0 +/- 5.9 and 14.3 +/- 9.9 hours following 5 mg and 10 mg transdermal doses, respectively. The differences between AUC0-alpha values with the oral syrup and the 5 mg and 10 mg transdermal doses were not significant when normalized to 2.09 mg (TPL base). The bioavailabilities of the 5 mg and 10 mg transdermal doses relative to the oral 2.09 mg doses were 0.89 +/- 0.32 and 1.04 +/- 0.33, respectively. Mild erythema and pruritus were the most common adverse effects secondary to TPL transdermal application. Drowsiness observed following oral TPL, was not evident following either transdermal dose. The results of this study, therefore, indicate that TPL can be absorbed transdermally, providing consistent plasma concentrations.

Administration, Cutaneous↗
PubMed1990

The clinical development of mupirocin.

Mupirocin is a novel antibiotic totally unrelated in chemical structure and mode of action to any other clinically useful class of antibiotics. It has greatest antibacterial activity against aerobic gram-positive cocci, namely, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus pyogenes, and other beta-hemolytic streptococci. Bactroban ointment is formulated as 2% mupirocin in polyethylene glycol ointment. No systemic absorption of mupirocin or its major metabolite, monic acid, has been detected in short courses of topical administration to healthy volunteers or to patients with epidermolysis bullosa after prolonged courses of therapy with Bactroban ointment. Randomized, multicenter, double-blind, vehicle-controlled clinical trials have shown that mupirocin is safe and effective for the treatment of impetigo.

Anti-Bacterial Agents↗
PubMed1990

Mupirocin-resistant Staphylococcus aureus after long-term treatment of patients with epidermolysis bullosa.

In a long-term, open study, 47 patients with epidermolysis bullosa were treated with topical 2% mupirocin (Bactroban) ointment to decrease bacterial infection and promote wound healing. This antibiotic is effective against gram-positive but not gram-negative organisms. No significant adverse effects were noted, although some patients have been treated for more than 4 years. We sought evidence in this patient population for the appearance of bacterial strains with decreased sensitivity to mupirocin. In five patients cultures from nonhealing wounds revealed Staphylococcus aureus resistance to mupirocin. Four of these patients were given oral antibiotics to which S. aureus was sensitive; they improved clinically, and cultures of their wounds became negative for pathogens.

Adult↗
PubMedDate not supplied

Ceftazidime versus ceftazidime plus tobramycin in febrile neutropenic children.

Although the effectiveness of antibiotic monotherapy in febrile neutropenic patients remains unproven, ceftazidime has been shown previously to be effective monotherapy for the empiric treatment of selective patients. The efficacy and safety of ceftazidime versus ceftazidime plus tobramycin was evaluated in the treatment of febrile children (range 8 months to 18 years) with neutropenia secondary to cancer chemotherapeutic agents. Of the evaluable 89 patients, 45 received ceftazidime and 44 received ceftazidime plus tobramycin for 5 to 10 days. At the end of therapy, 30 (67%) of the 45 ceftazidime-treated patients were clinically cured compared with 38 (86%) of 44 combination-treated patients. Thirteen (29%) of the patients treated with ceftazidime failed to respond clinically to treatment, versus four (9%) of the patients treated with ceftazidime/tobramycin (p = 0.046). This study suggests that ceftazidime as monotherapy in febrile neutropenic children may be inferior to combination therapy for optimal clinical response in these patients.

Adolescent↗
PubMedDate not supplied

A study of the nonprescription drug consumer's understanding of the ranitidine product label and actual product usage patterns in the treatment of episodic heartburn.

INTRODUCTION: A study of the consumer's understanding of the product label instructions and the resulting product use were conducted to support the switch of a product from prescription to nonprescription status. H2 receptor antagonists have recently been approved for nonprescription use. This study evaluated the consumer's understanding of the product label for ranitidine hydrochloride (Zantac 75) and the product usage pattern in the treatment of episodic heartburn. OBJECTIVES: Our objectives were to evaluate each aspect of the communication of labeled indications, contraindications, and directions for use of two label formats (old and new) for a new nonprescription preparation of ranitidine (Zantac) and to evaluate nonprescription consumers' use of ranitidine 75-mg tablets (as Zantac 75) in a medically unsupervised, at-home setting to observe whether these consumers used the product appropriately and followed directions as written on the package label. METHODS: Adult male and female consumers (n = 1405) in a shopping mall environment who were attracted to a poster asking, "Do you have stomach problems?" were recruited for the label comprehension phase (two different label formats) and the 3-week usage phase if after reading the Zantac 75 package label they decided the product was appropriate for them. No instructions regarding the use of Zantac 75 were provided beyond what was printed on the package label. Subjects recorded use in a diary and tablet counts were performed at the end of the study period. A medical history was also taken at this time and an assessment of product use was performed by a physician. RESULTS: In at least 84% of all subjects, both formats were effective in the communication of label objectives for the contraindication against concurrent prescription stomach ulcer medication, maximum daily dose, and maximum duration of dosing at maximum daily doses. The direction to take one tablet per dose was adhered to by 90% of consumers, and 90% of consumers followed the instructions to take no more than two tablets in 24 hours. Ninety-six percent of consumers complied with the direction not to take the maximum daily dose for more than 14 consecutive days. Notably, the maximum daily dose was taken for < or =3 consecutive days by 79% of consumers. The most frequently reported adverse events were headache, acute nasopharyngitis, upper respiratory tract infection, diarrhea, nausea, and menstrual cramps. CONCLUSION: The study demonstrated that the vast majority of a large sample of unsupervised consumers understood the package label and fully complied with the package directions by not exceeding the maximum daily dosage and length of use. Nonprescription consumers safely used Zantac 75 without medical supervision.

Adult↗
PubMedDate not supplied

Nonprescription doses of ranitidine are effective in the relief of episodic heartburn.

BACKGROUND: Many Americans have heartburn or related symptoms monthly and >20% experience heartburn at least once per day. Although many self-treat episodic heartburn with nonprescription antacids, newer treatments that decrease gastric volume and increase the pH of refluxed material are proving effective and popular in relieving heartburn. AIM: To evaluate the safety and efficacy of low-dose regimens of ranitidine for the relief of heartburn. METHODS: Adults with at least a 3-month history of heartburn were eligible for this randomized, double-blind, parallel group, multicenter dose-ranging study. Following a 1-week, open-label run-in phase to document baseline heartburn frequency, subjects were randomly assigned to receive treatment with one tablet of either ranitidine, 75 mg (n = 537); ranitidine, 25 mg (n = 539); or placebo (n = 544), to be taken as needed up to four times daily for 2 weeks for the relief of heartburn. RESULTS: The ranitidine 75-mg regimen was statistically (P < 0.05) and clinically (as defined a priori as > or =10% improvement) more effective than placebo in relieving episodic heartburn and in reducing antacid consumption. Ranitidine, 25 mg, was also statistically superior (P < 0.05) to placebo in providing heartburn relief. In addition, both regimens were superior to placebo in providing heartburn relief within 30 to 45 minutes of dosing. Ranitidine continued to be as effective over placebo in the treatment of the last heartburn episode as in the treatment of the first heartburn episode. Ranitidine was also equally effective over placebo in the treatment of mild, moderate, and severe episodes of heartburn. Ranitidine, 75 mg, was statistically superior to placebo for the relief of nocturnal heartburn episodes, whereas ranitidine, 25 mg, was not. All treatments were well tolerated and adverse events occurred no more frequently with the ranitidine regimens than with placebo. CONCLUSIONS: Low-dose ranitidine provides prompt and lasting relief of heartburn and has a safety profile comparable to that of placebo.

Adult↗