Sir, I read with interest Sarah Brown's comments (Letters, April 7) about the creation of "virtual" humans in the pursuit of drug testing and experimentation.

Such an idea, were it to become universal, might put an end to the abominations of vivisection once and for all.

Surely the recent fiasco at Northwick Park Hospital, where a drug "satisfactorily" tested on animals produced a near-fatal result when applied to human beings, forms its own indictment against the scientific validity (let alone the moral one) of this continued, barbaric practice.

Nicholas Wilson, Oxford