Should I take Aubagio or Tecfidera for my multiple sclerosis?

Question:
I'm not sure what my absolute lymphocyte count is but I do know that my cd4 was 239 in October 2015. I was told to stop taking Tecfidera. I have not been taking any MS medication since, waiting for my count to rise. My cd4 count has risen to 388 as of February16th. I just had it checked again on April 8th, and it had dropped to 337. I'm looking to start a treatment back now. I was considering taking 240mg of Tecfidera once a day or starting Aubagio. Do you have any idea what would have caused the drop in April? Also, do you think it would be wiser to start Tecfidera back at half dose or to just try Aubagio? Thanks in advance, C.H.

Answer:
There is a great deal of variability in CD4 counts. Women typically have CD4 counts greater than 500 and men typically have counts greater than 400.  This counts will fluctuate even within a 24 hour period and going from 388 to 337 would definitely be considered normal fluctuation. Since Tecfidera dropped your lymphocyte counts, I would not restart this medication. Tecfidera tends to lower CD8 counts more than CD4 counts, so I suspect your absolute lymphocyte count (what you should be measuring) is still less than 600. Aubagio is a reasonable choice but can also lower lymphocyte counts. If you try Aubagio, I would start on 7 mg and monitor your absolute lymphocyte count before increasing the dose to the usual 14 mg. 

Revere (Rip) Kinkel MD
Director of the Multiple Sclerosis Program
Professor of Clinical Neurosciences
University of California San Diego