Complex sentence: In a comparison of 15 antipsychotic drugs in effectivity in treating schizophrenic symptoms, clozapine was ranked first, a good deal more potent than amisulpride (2nd) and olanzapine (3rd), and twice as effective as haloperidol, quetiapine, and aripiprazole.
Split into simpler sentences: In a comparison of 15 antipsychotic drugs in effectivity in treating schizophrenic symptoms, clozapine was ranked first, demonstrating very strong potency. A good deal more potent than amisulpride (2nd) and olanzapine (3rd), and twice as effective as haloperidol, quetiapine, and aripiprazole.