There are many PDF editing programs that aren't from Adobe. Some of them are even free. Though you may get what you pay for. I haven't used any of them for that purpose, so I can't vouch for any particular program.
For a start,
here's one list that Google produced for me. It's created by a company that's putting their product at the top of the list (naturally), but you could check it or some of the others out. PDFescape and Wondershare seem to turn up in my search readily. Foxit makes good stuff, but I don't know if you can stille get an editor from them for free. Their full-featured version is called "PhantomPDF". It has a free trial download, but it might not let you save changes.