Developing antiviral medications seems to be a constant race that never ends. Considering the speed at which viruses become resistant to treatments, I doubt that we will ever be able to cure HIV and other serious viral diseases.
Science and technology has advanced so much, but we are still not fast enough to keep up with viruses. They're always one step ahead of us, finding new ways to survive and flourish.
The worst part is that because viruses use healthy body cells to replicate, we can't even attempt to wipe them out. If we do, we will also be wiping out normal body cells.