All drugs may not have the same effects in all people, researchers have revealed.
They know that small genetic differences between individuals lead to a range of outcomes.
Prof Peter Coveney and colleagues from University College London have now shown how this problem might be tackled using the latest genetic sequencing techniques and big computation, the BBC reported.
In a patient, researchers targeted the HIV protease molecule, which is critical in helping to build the viral particle, or virion, in a cell that eventually breaks out to infect the next cell.
The protease has a slightly different shape amongst everyone, in particular, in the protein's active zone where it slices the components that forms the next virion.
The team showed how one can take the specific viral sequence, infer the shape and then work out the drug that is most suitable for them.
The study has been published in the Journal of Chemical Theory and Computation.