The effects of procaine/haematoporphyrin on age-related decline: a double-blind trial

A randomized, double-blind study of procaine/haematoporphyrin (KH3) has been carried out over two years in a selected population of healthy elderly subjects. The period of study exceeds 500 patient years. The trial population was weighted to contain a larger proportion of subjects aged over 75 years than a standard population; those receiving active KH3 had similar characteristics on entry to those receiving placebo. Over the course of two years, KH3 was shown to be an active substance in that: (a) decrement in the consolidation of new learning was prevented in the treatment group (less than 1.0%, as against 38% in the placebo group); (b) the prevalence of incontinence increased significantly in the placebo group, but not in the active group (P less than 0.05); (c) there was a significant increase in grip strength in the active treatment group (+22%, P less than 0.01 v. placebo); (d) more adverse reactions were observed on treatment with KH3 (P less than 0.005).