A high speed agitation granulator method of preparing a substantially spherical granule for pharmaceutical use comprising a medicament for pharmaceutical use, wherein the medicament has an aqueous solubility of 0.01 to 0.30 g/ml, which method comprises introducing a mixture of medicament and excipients comprising at least 5% crystalline cellulose into the granulator and spraying on water or a mixture of ethanol and water as binder solution; a substantially spherical granule for pharmaceutical use comprising famciclovir and 5% or more crystalline cellulose, together with an optional coating; and a sachet containing a unit dose of famciclovir in the form of such granules.