Novartis Pharmaceuticals UK Ltd

4.8       Undesirable effects

Headache and nausea have been reported in clinical studies. These were generally mild or moderate in nature and occurred at a similar incidence in patients receiving placebo treatment. All other adverse reactions were added during postmarketing.

The pooled global placebo or active controlled clinical trials (n=2326 for Famvir arm) were retrospectively reviewed to obtain a frequency category for all adverse reactions mentioned below. The following table specifies the estimated frequency of adverse reactions based on all the spontaneous reports and literature cases that have been reported for Famvir since its introduction to the market.A total of 1,587 patients have received famciclovir at recommended doses in placebo- (n=657) and active- (n=930) controlled studies. These clinical studies were retrospectively reviewed to obtain a frequency category for all adverse reactions mentioned below. For adverse reactions which have never been observed in these studies, the upper limit of the 95% confidence interval is not expected to be higher than 3/X (based on the “rule of three”), with X representing the total sample size (n=1,587).

Adverse reactions (Table 2) are ranked under headings of frequency, using the following convention: very common (≥ 1/10); common (≥ 1/100 to < 1/10); uncommon (≥ 1/1,000 to < 1/100); rare (≥ 1/10,000 to < 1/1,000); very rare (< 1/10,000), not known (cannot be estimated from available data).

Table 2       Adverse reactions

* Never reported in clinical trials; category is based on the “rule of three”

Overall, adverse reactions reported from clinical studies with immunocompromised patients were similar to those reported in the immunocompetent population. Nausea, vomiting and abnormal liver function tests were reported more frequently, especially at higher doses.

 Children and adolescents

Famvir is not recommended for use in children and adolescents below 18 years of age due to lack of data on safety and efficacy. Paediatric population:

The safety and efficacy of famciclovir in children and adolescents aged less than 18 years have not been established. Currently available data are described in sections 5.1 and 5.2.

Paediatric population

Famciclovir experimental oral granules were evaluated in 169 paediatric patients 1 month to ≤12 years of age. One hundred of these patients were 1 to ≤12 years of age and were treated with famciclovir oral granules (doses ranged from 150 mg to 500 mg) either twice (47 patients with herpes simplex virus infections) or three times (53 patients with chickenpox) daily for 7 days. The remaining 69 patients (18 patients 1 to ≤12 months, 51 patients 1 to ≤12 years) participated in single-dose pharmacokinetic and safety studies using famciclovir oral granules (doses ranged from 25 mg to 500 mg). Famciclovir weight-based doses were selected to provide penciclovir systemic exposures similar to the penciclovir systemic exposures observed in adults after administration of 500 mg famciclovir. None of these studies comprised a control group; therefore a conclusion on the efficacy of the investigated regimens is not possible. The safety profile was similar to that seen in adults. However, systemic drug exposure in infants < 6 months of age was low, thus precluding any assessment of famciclovir’s safety in this age group.

Paediatric population

Repeated oral dosing of famciclovir (250 or 500 mg three times daily) to paediatric patients (6-11 years) infected with hepatitis B did not have a notable effect on the pharmacokinetics of penciclovir compared to single dose data. There was no accumulation of penciclovir.  In children (1-12 years) with herpes simplex virus infection or chickenpox given single oral doses of famciclovir (see section 5.1), the apparent clearance of penciclovir increased with body weight in a nonlinear manner. The plasma elimination half-life of penciclovir tended to decrease with decreasing age, from an average of 1.6 hours in the patients aged 6-12 years to 1.2 hours in patients aged 1-<2 years.