I was quite surprised today to hear that Campath is being withdrawn from the oncology marketplace. This will affect some patients with CLL and some patients with cutaneous lymphoma
Campath is a "bit player" in the management of CLL/NHL but for docs comfortable using it - it can be quite handy. It is one of the few drugs that clearly works in the group of patients with 17p deletion and can be effective when other drugs have failed provided the patient does not have bulky lymph nodes (Campath is good at marrow and circulating cells but doesn't often resolve big nodes).
We have always known that Campath profoundly lowers the immune system. Unfortunately, some of the initial studies were done in patients who were already heavily pre-treated. It probably made the drug look worse than it really is to study it in patients whose immune system was already beaten up by multiple rounds of fludarabine. None the less, you have to be on guard for all sorts of unusual infections such as CMV, PCP, shingles, etc.
Viagara was initially supposed to be a drug to treat hypertension and when men had an unusual "side effect" while taking the drug, it quickly got repurposed and became an extremely valuable asset for Pfizer. Similarly, there are reasons other than CLL where you may wish to lower the immune system. Multiple Sclerosis is just such a reason.
As is the case with lots of drugs - dose matters! They are hoping to show that lower campath doses can treat MS and avoid the infectious complications. If that works, it will probably be a much more valuable drug for its owners. Campath will be "re-branded" so I am not sure if it will still be available for patients with CLL.
To me, this is potentially bad news because although it was never much more than 5% of CLL patients ever treated with the drug - for that 5% it was quite good. It sounds like there may be patient access programs for patients with CLL - hopefully those materialize. Rumor has it that it may even be given away for free to patients with CLL - obviously that would be a good thing - but I will believe it when I see it. Furthermore, additional barriers may just make a hard to use drug even harder to get.
We are lucky that the CAL-101/GS-1101, ibrutinib drugs appear to have activity in 17p deleted cases - these drugs are coming just in time to help.