Powders for reconstitution

1. A method of treating an infant, child or elderly patient infected with HIV, said method comprising the oral administration once daily to said infant, child or elderly patient of a supersaturated solution consisting of 4-[[4-[[4-(2-cyanoethenyl)-2,6-dimethyl-phenyl]amino]-2-pyrimidinyl]-amino]benzonitrile or a stereoisomeric form thereof, and a water-soluble copolymer of vinylpyrrolidone and vinyl acetate in an aqueous medium wherein in the supersaturated solution the weight: weight ratio of copolymer of vinylpyrrolidone and vinyl acetate to 4-[[4-[[4-(2-cyanoethenyl)-2,6-dimethyl-phenyl]amino]-2-pyrimidinyl]-amino]benzonitrile or a stereoisomeric form thereof is about 9:1.

2. The method according to claim 1 wherein the supersaturated solution consists of (E)- 4[[4-[[4-(2-cyanoethenyl)-2,6-dimethyl-phenyl]amino]-2-pyrimidinyl]-amino]benzonitrile.