Eric R. Hurd

OBJECTIVE: To evaluate the efficacy and safety of anakinra in combination with methotrexate (MTX) in patients with active rheumatoid arthritis (RA). METHODS: Patients with moderate-to-severe active RA who were receiving MTX for 6 consecutive months, with stable doses for > or = 3 months (those with disease duration of >6 months but <12 years) were randomized into 6 groups: placebo or 0.04, 0.1, 0.4, 1.0, or 2.0 mg/kg of anakinra administered in a single, daily, subcutaneous injection. The primary efficacy end point was the proportion of subjects who met the American College of Rheumatology 20% improvement criteria (attained an ACR20 response) at week 12. RESULTS: A total of 419 patients were randomized in the study. Patient demographics and disease status were similar in the 6 treatment groups. The ACR20 responses at week 12 in the 5 active treatment plus MTX groups demonstrated a statistically significant (P = 0.001) dose-response relationship compared with the ACR20 response in the placebo plus MTX group. The ACR20 response rate in the anakinra 1.0-mg/kg (46%; P = 0.001) and 2.0-mg/kg (38%; P = 0.007) dose groups was significantly greater than that in the placebo group (19%). The ACR20 responses at 24 weeks were consistent with those at 12 weeks. Similar improvements in anakinra-treated subjects were noted in individual ACR components, erythrocyte sedimentation rate, onset of ACR20 response, sustainability of ACR20 response, and magnitude of ACR response. Anakinra was safe and well tolerated. Injection site reaction was the most frequently noted adverse event, and this led to premature study withdrawal in 7% (1.0-mg/kg group) to 10% (2.0-mg/kg group) of patients receiving higher doses. CONCLUSION: In patients with persistently active RA, the combination of anakinra and MTX was safe and well tolerated and provided significantly greater clinical benefit than MTX alone.

In an experimental arthritis induced by injection of bovine serum albumin or egg albumin into the joints of previously immunized animals, it has been demonstrated that the major portion of the radioactively labeled antigens injected was localized to avascular collagenous tissues in the joint, i.e., articular cartilage, menisci, and intra-articular ligaments. The antigens were partially eluted from the tissues with 5 M guanidine solution, but not with acid buffers or by 3 M magnesium chloride. The radioactive material eluted with guanidine was at least 80% precipitable by specific antisera. The radioactively labeled-inducing antigen was identified on the surface of articular collagenous tissues from arthritic joints by radioautography and immunofluorescence. Rabbit immunoglobulin and C3 were demonstrated in the same sites by immunofluorescence. The presence of specific antibody in collagenous tissues was demonstrated by the selective in vitro binding of (125)I-labeled-inducing antigen to menisci from arthritic joints of immunized animals. The evidence obtained indicates that in this model of chronic arthritis, the inducing antigen persists for long periods of time in the form of immune complexes in the surface layers of the intra-articular collagenous tissue. The antigen retained in this form may be responsible for the chronicity of the synovitis by serving as a direct stimulus for the maintenance of prolonged antibody synthesis in the synovium and by providing a source of complement-fixing antigen-antibody complexes for the mediation of joint inflammation.

Abstract Ninety‐three patients with a variety of joint diseases were studied for evidence of immune complexes in articular collagenous tissues. Frozen sections of freshly obtained biopsies of hyaline articular cartilage and menisci were stained with fluoresceinated monospecific antisera for evidence of human immunoglobulins (IgG, IgM, IgA) and the β 1c component of complement. The criterion for the presence of complexes was the staining of two or more immunoglobulins and β 1c in an identical location of sequentially cut sections. Of the 42 patients with rheumatoid arthritis (RA) 83% were positive by this criterion. In those with classic RA the incidence was 92%. Sixteen patients with fresh joint trauma or nonarthritic disease had negative findings. Among 26 patients with noninflammatory disease, 4 of 8 with polyarthritis whose features suggested primary degeneration, 1 of 11 patients with secondary degenerative arthritis, and a single case of synovial osteochondromatosis had positive findings. Among 9 patients with miscellaneous inflammatory arthritides, all of 3 with psoriatic arthritis were negative; however 2 of 6 with other inflammatory arthritides were positive. The findings in classic RA suggest that immune complexes are deposited in the articular collagenous tissues. The persistence of these complexes may play a significant role in the chronicity of the synovitis.

Female B/W mice spontaneously develop an autoimmune disease that is similar to systemic lupus erythematosus. Antibodies to doublestranded DNA (dsDNA) and antinuclear antibodies develop in aging animals; death from immune complex-mediated glomerulonephritis occurs from 8 to 12 mo of age. It has been reported that prostaglandin (PG)E(1) treatment of such mice prolongs survival. In the present study, four groups of female B/W mice were studied beginning at 6-11 wk of age on the following regimens: (a) a synthetic diet that contained 20% safflower oil, (b) a standard laboratory chow diet, (c) a standard diet together with injections of PGE(1), and (d) an essential fatty acid-deficient synthetic diet that contained 20% coconut oil. All animals were tested monthly for antinuclear antibodies and anti-dsDNA. Kidney tissue was obtained for light and immunofluorescence microscopy when animals were dying. All disease manifestations were altered strikingly in the essential fatty acid (EFA)-deficient animals. Intermediate benefit was seen in PGE(1)-treated animals. 7% of the control animals and 18% of safflower oil-fed animals survived to 10 mo. In contrast, the PGE(1)-treated and EFA-deficient mice had a similar survival rate (78-88%). At age 16 mo, 78% of EFA-deficient mice and 45% of PGE(1)-treated mice were alive. 25% of the PGE(1)-treated and 55% of the EFA-deficient animals survived to 20 mo. Serum anti-dsDNA appeared at age 5 mo in safflower oil-fed and control animals, but not until 9 and 12 mo for PGE(1)-treated and EFA-deficient animals, respectively. All kidneys from 7- to 9-mo-old safflower oil-fed and control animals and the majority of kidneys from PGE(1)-treated animals were abnormal by light and immunofluorescence microscopy. Kidneys from EFA-deficient animals were essentially normal at 10 mo. At 13 mo, all PGE(1)-treated animals examined had significant kidney involvement, whereas none of the EFA-deficient animals had glomerulonephritis. These findings demonstrate that an EFA-deficient diet has a beneficial effect on murine lupus erythematosus.