Publications by authors named "Thomas M Ludden"

Population pharmacokinetics (PK) of FVIII activity-time profiles following recombinant factor VIII Fc fusion protein (rFVIIIFc) and recombinant factor VIII (rFVIII) dosing were evaluated in previously treated patients with severe hemophilia A (from two clinical trials). Potential covariates that may be determinants of variability in FVIII activity were identified. A 2-compartment model adequately described the PK of both compounds.

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Background: Hispanics are the largest and fastest growing minority group in the United States. Charlotte, NC, had the 4th fastest growing Hispanic community in the nation between 1990 to 2000. Gaining understanding of the patterns of health care use for this changing population is a key step toward designing improved primary care access and community health.

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Introduction: A key element for reducing health care costs and improving community health is increased access to primary care and preventative health services. Geographic information systems (GIS) have the potential to assess patterns of health care utilization and community-level attributes to identify geographic regions most in need of primary care access.

Methods: GIS, analytical hierarchy process, and multiattribute assessment and evaluation techniques were used to examine attributes describing primary care need and identify areas that would benefit from increased access to primary care services.

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Purpose: To evaluate the likelihood-based methods for handling data below the quantification limit (BQL) using new features in NONMEM VI.

Methods: A two-compartment pharmacokinetic model with first-order absorption was chosen for investigation. Methods evaluated were: discarding BQL observations (M1), discarding BQL observations but adjusting the likelihood for the remaining data (M2), maximizing the likelihood for the data above the limit of quantification (LOQ) and treating BQL data as censored (M3), and like M3 but conditioning on the observation being greater than zero (M4).

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Leflunomide is a pyrimidine synthesis inhibitor used in the treatment of rheumatoid arthritis. Data from two clinical studies were used to establish a population pharmacokinetic (PPK) model for the active metabolite (M1) of leflunomide in patients with juvenile rheumatoid arthritis (JRA) and determine appropriate pediatric doses. Seventy-three subjects 3-17 years of age provided 674 M1 concentrations.

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In population pharmacokinetic (PK) studies, patients' drug plasma profiles are routinely analyzed assuming that all patients took their drug at the times and in the amounts specified. However, patient non-compliance with the prescribed drug regimen is a leading source of failure to drug therapy. It has been reported that over 30% of patients routinely skip doses regardless of their disease, prognosis, or symptoms.

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