DESCRIPTION
BILTRICIDE® (praziquantel) is a trematodicide provided in tablet form for the oral treatment of schistosome infections and infections due to liver fluke.
BILTRICIDE® (praziquantel) is 2-(cyclohexylcarbonyl)-1,2,3,6,7, 11b-hexahydro-4H-pyrazino [2, 1-a] isoquinolin-4-one with the molecular formula; C19H24N2O2. The structural formula is as follows:
Praziquantel is a white to nearly white crystalline powder of bitter taste. The compound is stable under normal conditions and melts at 136-140°C with decomposition. The active substance is hygroscopic. Praziquantel is easily soluble in chloroform and dimethylsulfoxide, soluble in ethanol and very slightly soluble in water.
BILTRICIDE tablets contain 600 mg of praziquantel. Inactive ingredients: corn starch, magnesium stearate, microcrystalline cellulose, povidone, sodium lauryl sulfate, polyethylene glycol, titanium dioxide and hypromellose.
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CLINICAL PHARMACOLOGY
Praziquantel induces a rapid contraction of schistosomes by a specific effect on the permeability of the cell membrane. The drug further causes vacuolization and disintegration of the schistosome tegument.
After oral administration BILTRICIDE® is rapidly absorbed (80%), subjected to a first pass effect, metabolized and eliminated by the kidneys. Maximal serum concentration is achieved 1-3 hours after dosing. The half-life of praziquantel in serum is 0.8-1.5 hours.
Special Populations: The pharmacokinetics of praziquantel were studied in 40 patients with Schistosoma mansoni infections with varying degrees of hepatic dysfunction (See table1). In patients with schistosomiasis, the pharmacokinetic parameters did not differ significantly between those with normal hepatic function (Group 1) and those with mild (Child-Pugh class A) hepatic impairment. However, in patients with moderate-to-severe hepatic dysfunction (Child-Pugh class B and C), praziquantel half-life, Cmax, and AUC increased progressively with the degree of hepatic impairment. In Child-Pugh class B, the increases in mean half-life, Cmax, and AUC relative to Group 1 were 1.58-fold, 1.76-fold, and 3.55-fold, respectively. The corresponding increases in Child-Pugh class C patients were 2.82-fold, 4.29-fold, and 15-fold for half-life, Cmax, and AUC.
Table 1: Pharmacokinetic parameters of praziquantel in four groups of patients with varying degrees of liver function following administration of 40 mg/kg under fasting conditions. Patient
Group | Half-life
(hr) | Tmax
(hr) | Cmax
(µg/mL) | AUC
(µg/mL* hr) |
| a) p<0.05 compared to Group 1 |
| b) p<0.05 compared to Group 2 |
| c) p<0.05 compared to Group 3 |
Normal hepatic
function
(Group 1) |
2.99 ± 1.28 |
1.48 ± 0.74 |
0.83 ± 0.52 |
3.02 ± 0.59 |
Child-Pugh A
(Group 2) |
4.66 ± 2.77 |
1.37 ± 0.61 |
0.93 ± 0.58 |
3.87 ± 2.44 |
Child-Pugh B
(Group 3) |
4.74 ± 2.16a |
2.21 ± 0.78a,b
|
1.47 ± 0.74a,b |
10.72 ± 5.53a,b |
Child-Pugh C
(Group 4) |
8.45 ± 2.62a,b,c |
3.2 ± 1.05a,b,c |
3.57 ± 1.30a,b,c |
45.35 ± 17.50a,b,c |
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