Overdose : מינון יתר

9      OVERDOSAGE
In a healthy volunteer repeat-dose pharmacokinetic trial evaluating high-dose combinations of LEXIVA plus ritonavir, an increased frequency of Grade 2/3 ALT elevations (greater than 2.5 x ULN) was observed with LEXIVA 1,400 mg twice daily plus ritonavir 200 mg twice daily (4 of 25 subjects). Concurrent Grade 1/2 elevations in AST (greater than 1.25 x ULN) were noted in 3 of these 4 subjects. These transaminase elevations resolved following discontinuation of dosing.
There is no known antidote for LEXIVA. It is not known whether amprenavir can be removed by peritoneal dialysis or hemodialysis, although it is unlikely as amprenavir is highly protein bound.
If overdosage occurs, the patient should be monitored for evidence of toxicity and standard supportive treatment applied as necessary.

10     DESCRIPTION
LEXIVA (fosamprenavir calcium) is a prodrug of amprenavir, an inhibitor of HIV protease. The chemical name of fosamprenavir calcium is (3S)-tetrahydrofuran-3-yl (1S,2R)-3-[[(4- aminophenyl) sulfonyl](isobutyl)amino]-1-benzyl-2-(phosphonooxy) propylcarbamate monocalcium salt. Fosamprenavir calcium is a single stereoisomer with the (3S)(1S,2R) configuration. It has a molecular formula of C25H34CaN3O9PS and a molecular weight of 623.7.
It has the following structural formula:



Fosamprenavir calcium is a white to cream-colored solid with a solubility of approximately 0.31 mg per mL in water at 25°C.
LEXIVA tablets are available for oral administration in a strength of 700 mg of fosamprenavir as fosamprenavir calcium (equivalent to approximately 600 mg of amprenavir). Each 700-mg tablet contains the inactive ingredients microcrystalline cellulose, croscarmellose sodium, povidone K30, magnesium stearate, and colloidal anhydrous silica. The tablet film-coating contains the inactive ingredients hypromellose, titanium dioxide, triacetin, and iron oxide red.