SOLVED. Thriller, different kinds of assassination [s]

[Michael]

I think I read this 10-15 years ago, modern setting, aimed towards adults. I can't recall any of the plot, but think it was a global conspiracy type situation. I don't recall anything about the cover or author.

There was an assassin who lived on a deserted island and trained by punching holes in a sandy beach.

There was another character who would have been/was a professional boxer, but he was always breaking his hands, the bones were too fragile.

There was a drug which caused those who took it to become depressed and kill themselves immediately.

I think there was another type of strange drug that did something else (maybe eroded free will and made the person do whatever they were told?)

[Tab]

Maybe, Brothers by William Goldman ?

Here's a descrip from Publisher's Weekly:
Believed dead, Scylla has in fact been hidden away, his face altered, his voice changed, making him the perfect killing machine. His assassin's skills honed to perfection, he is brought back into action by "Division," the mysterious agency for which he works, as part of a plan to permanently alter the balance of world nuclear power. The author spices the plot by introducing a host of super-secret weapons, among them a drug that forces compliance, a liquid that induces suicide, and an almost superhuman killer simply known as The Blonde.

If not, do you remember anything about the cover?

[Michael]

That sounds right, I ordered it and I'll update in a few days when I receive it.

Thank you!

[Michael]

Haven't read all the way through, but just flipped around a bit, and it's the one. Thanks again, Tab!