Relative Bioavailability Trial of L-Praziquantel in Healthy Volunteers

Time prior to the first measurable (non-zero) concentration (tlag) of drug L-PZQ

The AUC (0-t) was defined as the area under the plasma concentration versus time curve from time zero to time of last quantifiable concentration at or above the lower limit of quantification (AUC0-t) of L-PZQ.

Extrapolated AUC from time tlast to infinity given as percentage from AUC0-inf. AUCextra =(last predicted concentration [Clast pred] divided by terminal elimination rate constant [lambda z]) divided by AUC0-inf., where Clast pred is the last predicted concentration.

The apparent terminal half-life was calculated by dividing natural log 2 with lambda z (ln2/lambda Z); where lambda Z is the terminal rate constant.

Relative bioavailability (Frel) was calculated for L-PZQ only (treatment A versus treatment B) using the formula: Frel = (AUC0-inf (test or Treatment A)/AUC0-inf (reference or treatment B)) multiplied by 100.

The lambda z was calculated as the negative of the slope of the log-linear regression of the natural logarithm concentration-time curve during the terminal phase.

The CL/f of L-PZQ was a measure of the rate at which it was metabolized or eliminated by normal biological processes. Clearance obtained after oral dose was influenced by the fraction of the dose absorbed. The CL/F of L-PZQ from plasma was calculated using the formula: Dose divided by area under the concentration time curve from time zero to infinity (AUC0-inf).

The Vz/f was defined as the theoretical volume in which the total amount of L-PZQ required to uniformly distribute to produce the desired plasma concentration of L-PZQ. Apparent volume of distribution after oral dose (Vz/F) was influenced by the fraction absorbed. The Vz/f was calculated by dividing the dose with area under the concentration time curve from time zero to infinity multiplied with terminal elimination rate constant (lambda z) (Vz/f=Dose/( AUC0-inf* lambda z).

An Adverse Event (AE) was defined as any new untoward medical occurrences/worsening of pre-existing medical condition without regard to possibility of causal relationship. A Serious Adverse Event (SAE) was an AE that resulted in any of the following outcomes: death; life threatening; persistent/significant disability/incapacity; initial or prolonged inpatient hospitalization; congenital anomaly/birth defect. TEAEs were adverse events that occurred between the first dose of study drug and up to 3-10 days after the last dose that were absent before treatment or that worsened relative to pretreatment state. Subjects who discontinued and who died due to TEAEs were also reported.

Each administration was assessed at 0 minutes on Day 1 for flavor, smell, sweetness, overall liking of the medicine and at 2-5 minutes on Day 1 for taste in mouth and acceptability to swallow using a modified 100 millimeter (mm), visual analog scale (VAS) incorporating a facial hedonic scale, where lower score (0) indicates "not acceptable/not liked at all" and higher score (100) indicates "very acceptable/liked very much".

Any clinically significant changes in laboratory evaluations ECGs,physical examination (body weight) and vital signs (temperature, blood pressure, pulse rate) were recorded as treatment emergent adverse events. Following parameters were analyzed for laboratory examination: hematology (haemoglobin, hematocrit, red blood cell count, mean cell hemoglobin [MCH], MCH concentration, mean cell volume, white cell count, platelets, neutrophils, lymphocytes, monocytes, eosinophils, Basophils); serum chemistry (sodium, potassium, calcium, inorganic phosphate, creatinine, total protein, albumin, urea, uric acid, aspartate aminotransferase [AST], alanine aminotransferase [ALT] gamma glutamyl transpeptidase, total bilirubin, alkaline phosphatase, glucose, triglycerides cholesterol); urinalysis (protein, glucose, ketones, pH, blood, leukocytes, nitrite); The 12-lead ECGs were recorded after the subjects had rested for at least 5 minutes in supine position.