Switching between etanercept and infliximab

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Jun 25, 2002

Switching between etanercept and infliximab

Stockholm, Sweden ‹ If a patient with rheumatoid arthritis (RA) who is being

treated with one of the TNF blockers is failing to respond to treatment or

is not tolerating the side effects, it's worth trying the other product. In

clinical practice this approach is a " reasonable therapeutic option, " says a

team of Swedish researchers.

The team reported clinical results following switches between etanercept

(Enbrel®, Immunex) and infliximab (Remicade®, Centocor) at the recent EULAR

meeting. The two drugs have similar clinical efficacy, but there have been

no head-to-head trials, and while they have a similar mechanism of action,

it's not identical, lead researcher Dr F van Vollenhoven

(Rheumatology, Karolinska Hospital, Sweden) commented. His team set out to

answer the question: " if patients fail one TNF blocker, doesn't it make

sense to try the other? "

The data of patients switching from one TNF blocker to another came from the

Stockholm TNF-alpha Registry (STURE) database, which collates information on

safety and efficacy in patients taking etanercept and infliximab at the

Karolinska and Huddinge hospitals. For the purposes of this study, the

registry identified 18 patients treated with etanercept who switched to

infliximab and 13 who did the reverse.

" In patients who fail to respond to etanercept, better clinical results can

be achieved with infliximab. "

Among the group of 18 patients switching from etanercept to infliximab, 14

patients (the majority with RA) switched because of a lack of efficacy, 2

patients because of adverse events (AEs), and 2 for other reasons. The

Disease Activity Score (DAS) 28 improved from baseline on etanercept and

continued to improve following the switch (p<0.05). The ACR20 response was

also improved at 3 to 6 months, although not significantly. Overall, 13

patients improved, 2 stayed the same, and 1 got worse. " In patients who fail

to respond to etanercept, better clinical results can be achieved with

infliximab, " said van Vollenhoven.

Similar results with etanercept

In the other group of 13 patients being treated with infliximab (plus

concomitant methotrexate), 12 were switched to etanercept because of AEs

(mostly infusion reactions, as well as liver toxicity), and 1 due to lack of

efficacy. They initially did poorly on etanercept but then improved.

Swollen joint count and ACR-N were similar (not significantly different),

while ACR20 response was identical. Overall 2 patients got better, 8 stayed

the same, and 1 got worse. Van Vollenhoven suggested that initial antibody

production from the infliximab treatment might explain the improvement in

patients who got better.

" For patients who cannot tolerate infliximab, etanercept can give at least

similar results, and in some cases better. "

" In patients who cannot tolerate infliximab, etanercept can give at least

similar results, and in some cases better [results], " he said, concluding

that it makes sense to switch between the drugs in routine clinical

practice.

Second study also finds drug switch to be beneficial

In another population study presented in a poster at EULAR, researchers

indicate that switching between etanercept and infliximab is beneficial in

cases of AE or lack of efficacy following the use of the first drug.

Dr Olivier Brocq (Rheumatology, CHU Archet 1, Nice, France) and colleagues

looked at a group of patients who, after 4 months on anti-TNF-alpha therapy,

were switched to the other drug if they were nonresponders (according to

ACR20 criteria) or had AEs.

" In our experience, in more than 1 case out of 2, the switch was

successful. "

Of 131 patients who received anti-TNF-alpha therapy during the study period

(August 1999 to January 2002), 64 were on etanercept and 67 were on

infliximab. A switch was required in 14 patients‹6 from etanercept to

infliximab and 8 from infliximab to etanercept. Average disease duration in

these patients before anti-TNF-alpha therapy was 17 years, and the patients

received an average of 4.8 DMARDs plus 10.6 mg prednisolone per day.

The researchers indicate that there were 8 positive results (ie, 8 patients

responded to the new drug) out of the 14 patients‹3 out of 6 switching from

etanercept to infliximab (associated with a low dose of MTX, leflunomide, or

azathioprine), and 5 out of 8 switching from infliximab to etanercept.

" These preliminary data suggest that there is no reason, when the first

administered anti-TNF-alpha drug should be stopped, to exclude a patient

with severe RA from treatment with the other one, " conclude Brocq et al. " In

our experience, in more than 1 case out of 2, the switch was successful. "