Researchers in Canada conducted a systemic literature search for randomized control trials (RCTs) examining the efficacy of anti-tumor necrosis factor (TNF) biologic agents, including adalimumab (ADA), etanercept (ETN), golimumab (GOL) and infliximab (INF), for treating psoriatic arthritis (PsA). Relative risks (RR) for the psoriatic arthritis response criteria (PsARC), mean differences (MDs) for improvements from baseline for the Health Assessment Questionnaire (HAQ) by PsARC responders and nonresponders and MD for improvements from baseline for the psoriasis area and severity index (PASI) were measured.
Nineteen publications, representing seven RCTs (two used ADA; two, ETN; two, INF; and one, GOL) were included. Compared with controls, all anti-TNFs were significantly better; however , indirect comparison did not reveal any statistically significant differences between drugs.
GOL yielded the highest RR (3. 45; 95% CI, 2 . 39-4. 99) for PsARC response, followed by ETN (RR=3. 19; 95% CI, 2 . 31-4. 42), and INF and ADA produced smaller RRs (2. 64 and 2 . 39, respectively). ETN (0. 43) and INF (0. 41) produced the largest MD for HAQ improvements by PsARC responders. ADA had a notably lower MD (0. 09) for PsARC nonresponders compared with the other anti-TNF agents (range 0. 16 to 0. 23). INF yielded the largest MD for PASI improvements (6. 44), with GOL the second largest (4. 90) and ETN the smallest (3. 13).
“There is insufficient statistical evidence to demonstrate differences in effectiveness between available anti-TNFs for PsA, ” the researchers concluded. “Since the analyzed outcomes play an important role informing quality adjusted life years [QALYs, and thus cost per QALY] in cost-effectiveness analyses, it seems reasonable to insist that the cost-effectiveness analyses on which the current drug indications are based be revised to check the robustness of their findings. ”