Endometriosis is associated with an inflammatory response. Hence infliximab, an anti-TNF-α monoclonal antibody, might relieve pain.
A randomized placebo-controlled trial was designed with 21 women with severe pain and a rectovaginal nodule of at least 1 cm. After 1 month of observation, three infusions of infliximab (5 mg/kg) or placebo were given. Surgery was performed 3 months later and follow-up continued for 6 months. The primary end-point was pain (dysmenorrhea, deep dyspareunia and non-menstrual pain) rated at each visit by the clinician and on a daily basis by the patient who in addition scored pain by visual analog pain scale and analgesia intake. Secondary end-points included the volume of the endometriotic nodule, pelvic tenderness and the visual appearance of endometriotic lesions at laparoscopy.
Pain severity decreased during the treatment by 30% in both the placebo ( P < 0.001) and infliximab groups ( P < 0.001). However, no effect of infliximab was observed for any of the outcome measures. After surgery, pain scores decreased in both groups to less than 20% of the initial value.