Ribavirin Dosing Should be Based on Renal Function Not Body Weight for Chronic Hepatitis C

[Guest guest]

DGReview

Ribavirin Dosing Should be Based on Renal Function Not Body Weight for Chronic

Hepatitis C

A DGReview of : " Evidence that plasma concentration rather than dose per kilogram

body weight predicts ribavirin-induced anaemia "

Journal of Viral Hepatitis

02/06/2004

By Beth Nierengarten

For patients with chronic hepatitis C who receiving combination treatment with

interferon and ribavirin, dosing of ribavirin should be based on renal function

instead of body weight, reports a study from Sweden.

Although ribavirin dosing is currently based on body weight, a more

pharmacological and physiological dosing strategy may be to dose ribavirin

according to renal function. Based on the fact that ribavirin is eliminated

primarily through the kidneys and previously published data that shows ribavirin

plasma concentrations are mainly determined by the kidneys, the authors of this

study hypothesise that plasma concentrations are probably more closely related

to side effects of ribavirin, particularly anaemia, than body weight.

To test this hypothesis, Karin hl, MD, and colleagues, Karolinska Institute

and Huddinge University Hospital, Stockholm, prospectively examined 213

ribavirin samples collected from 108 consecutive patients undergoing standard

treatment with combination interferon and ribavirin (initial dose of 800-1200

mg/daily). Plasma samples were taken 12 hours after dosing at week 4, 8, and 12

of treatment, and ribavirin plasma concentrations were measured using

high-performance liquid chromatography. Changes in haemoglobin levels and

creatinine concentration were also measured.

Based on 209 evaluable plasma samples, the mean ribavirin concentration was 8.19

µ (range of 0-17.7 µ). No apparent association was found between the absolute or

relative drop in haemoglobin and dose of ribavirin per kilogram (kg) of

bodyweight, although a trend was observed in a correlation between ribavirin

concentration and drop in haemoglobin. A dose-response curve showed that a

maximal drop in haemoglobin was achieved at a 4.4 µ concentration of ribavirin.

These data support the hypothesis that a plasma concentration and not body

weight is more strongly associated with ribavirin-induced anaemia. The authors

conclude that ribavirin dosing should be based on creatinine clearance and not

on body weight given that ribavirin concentrations depend primarily on renal

function.

J Viral Hepat 2004 Jan;11:1:84-87. " Evidence that plasma concentration rather

than dose per kilogram body weight predicts ribavirin-induced anaemia "

[Guest guest]

I heard (the operative word is " heard " ) from a few people in my area that

they are no longer doing the weight based peg cuz they ended up over

medicating people and are returning to a more standard prescription of peg.

Maybe they are watching renal functions? I didn't think to ask this.

My creatinine increased on treatment.

Alley

[Guest guest]

I heard (the operative word is " heard " ) from a few people in my area that

they are no longer doing the weight based peg cuz they ended up over

medicating people and are returning to a more standard prescription of peg.

Maybe they are watching renal functions? I didn't think to ask this.

My creatinine increased on treatment.

Alley

[Guest guest]

I heard (the operative word is " heard " ) from a few people in my area that

they are no longer doing the weight based peg cuz they ended up over

medicating people and are returning to a more standard prescription of peg.

Maybe they are watching renal functions? I didn't think to ask this.

My creatinine increased on treatment.

Alley

[Guest guest]

I heard (the operative word is " heard " ) from a few people in my area that

they are no longer doing the weight based peg cuz they ended up over

medicating people and are returning to a more standard prescription of peg.

Maybe they are watching renal functions? I didn't think to ask this.

My creatinine increased on treatment.

Alley