Is it ethical for drug companies to make sooooooo much money from people with cancer?

I have been fortunate to be treated with Opdivo for a year and a half, even though I haven't had any treatment in over 2 months.  Yes, I hope to return to get my Yervoy/Opdivo combo treatment this week, as long as my liver enzymes cooperate.  And yes, I do hope to continue with immune and target therapies for as long as I can.  All that said, something has been really bugging me for a while now, especially when just about every article about cancer research is focusing on immune therapy drugs as if they are miracle drugs - what is bugging me is the fact that these therapies are continuous and NOT A CURE . 

Just today, I read another article that said that former President Jimmy Carter was cured.  He isn't cured, and just like the rest of us, he has to continue to get regular Keytruda treatments every couple of weeks.  There is NO end to paying out for these very expensive drugs.  In other words, the for-profit drug companies are making a SHIT LOAD of money at the expense of those of us with advanced cancer. 

Let's put it another way:  while I am grateful to be alive and have a decent quality of life, The for-profit drug companies have NO incentive to cure me or my fellow cancer patients.  These companies instead are VERY HAPPY to have an extremely expensive drug that we literally have to purchase from them every two weeks or we DIE. 

Here is the thing, the Republican controlled government is in the process of repealing the Affordable Care Act (ACA).   ACA removed the spending cap per person that insurance companies used to place on how much they will cover.  I have recently read that the spending cap may be reintroduced in the Republican's health care replacement.  If that happens, it won't take long for those of us who rely on these ridiculously expensive treatments to reach their spending limits, and since these drugs cost thousands each month, unless we are rich, we will all just DIE. 

Bottom line, my life may be in the hands of the idiots currently in charge of the gov't - unless the greedy drug companies lobby to not have a cap in the ACA replacement, so they can continue to exploit their captive cancer clients.

Either way,  NOT a comforting thought.