Some other ARBs and ACE inhibitors may work less effectively or not at all (some ARBs I know to be good - besides telmisartan - are valsartan,
irbesartan, candesartan. Most of them are good EXCEPT
for losartan, which
is a surmountable antagonist and, theoretically, would lose its effect over time).
Next fact: you need to take a high dose.