Treatment of latent TB infection in patients with rheumatoid arthritis

The World Health Organization advocates several regimens for the treatment of latent tuberculosis (TB) infection. Are there any new data comparing different treatments that suggest which regimen would be optimal for adults with rheumatoid arthritis (RA) who have been treated for latent TB infection before starting biologic therapy for RA?

Lori Whitehead: Unfortunately, there is still not a lot of clarity in this area. What is clear, as you stated, is that the persons who require biologic agents who are felt to have latent TB infection should have pretreatment for latent TB infection. Unfortunately, there are not any consistent guidelines and there is not a lot of hard data to suggest which regimen would be better than another, and there is not a lot of data to suggest at what point should [the patients] be treated, should they receive the latent TB infection drugs – like isoniazid or rifapentine – should they receive that for one month before starting the biologic therapy, should they be on it for 3 months, or can the two drugs be started concurrently.

I think that most of the experts in this field are using extra information. For example, if you are using a biologic agent like infliximab – it is one of the monoclonal tumor necrosis factor (TNF)-alpha blockers – this has been shown to be a more potent stimulator of reactivation of TB. A couple of studies have shown that persons have reactivated with TB, that have latent TB, that are put on infliximab as soon as one month after the infliximab was started, as opposed to etanercept or the other ones that are nonmonoclonal, more dissoluble TNF blockers; those are less potent stimulators of reactivation and when it does occur, it is usually later on.

What I do if they are going on Remicade (infliximab), I would very strongly recommend that they have 3 full months of treatment before going on the infliximab, or if it is one of the other biologic agents, it may be one month. Of course, if the patient is in direct need of biologic agents – for example, someone with a flare of ulcerative colitis or Crohn disease – you have to look at the life-threatening aspect of that illness, and in those cases I say start the biologic [agent] right away: I will put the TB drug on, prophylactic them the right way, and we will do close monitoring.