How to reset a run??

[Viewbot]

Is there any kind of button combination that lets you reset the run, so I dont have to go to the game menu every time I get bad starting items

[Frank]

S U I C I D E I S A C O M B I N A T I O N .
Seriously, If you mean starting a new and different run without quitting the game, after dying there's the restart button. Also, in Rebirth there's an unlockable feature that permits you to restart the same identical run, but it's kind of an end game sorta of thing, and I don't think that you are interested in that.

[TEROBERO]

Hold the "R" button. (which is the first letter of restart)