Gamma-Linolenic Acid Treatment of Rheumatoid Arthritis
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ARTIIRIl'IS & RI1EIJMhl'ISM Vol. 39, Yo. 11. November 1996. pp 1808-1817 1808 0 19Y6, American Collegc of Rhcumatology ____ -. .. ~ - GAMMA-LINOLENIC ACID TREATMENT OF RHEUMATOID ARTHRITIS A Randomized, Placebo-Controlled Trial ROBERT B. ZURIER. RONALD G. ROSSETTI, ERIC W. JACOBSON, DEBORAH M. DEMAKCO. NANCY Y. LIU. JOSEPH E. TEMMING. BERNADETTE M. WHITE, and MICIIAEL LAPOSATA Objective. To assess the clinical efticacy and ad- GLA is available as a component of several plant seed verse effects of y-linolenic acid (GLA),a plant seed oils and is usually taken in far lower doses than were oil-derived unsaturated fatty acid that suppresses in- used in this trial. It is not approved in the United States flammation and joint tissue injury in animal models, in for the treatment of any condition, and should not be the treatment of active rheumatoid arthritis (RA). viewed as therapy for any disease. Further controlled Methods. Fifty-six patients with active RA were studies of its use in RA are warranted. randomized to treatment groups in a 6-month, double- blind trial of GLA versus placebo. This was followed by Gamma-linolenic acid (GLA; 18:3 06) is an a 6-month, single-blind trial during which all patients essential fatty acid (Figure 1) found in certain plant seed received GLA. Patients were treated with 2.8 gm/day of oils. It is metabolizcd to dihomo-y-linolcnic acid GLA as the free fatty acid or with sunflower seed oil (DGLA; 20:3 06). the immediate precursor of prosta- (placebo) administered in identical capsules. glandin E, (PGE,), an cicosanoid with known antiin- Resulrs. Treatment with GLA for 6 months re- flammatory and immunoregulatory properties (1-4). sulted in statistically significant and clinically relevant GLA and DGLA also modulate immune rcsponses in an reductions in the signs and symptoms of disease activity eicosanoid-independent manner by acting directly on T in patients with RA. Overall meaningful responses (at lymphocytes (5-7). GLA suppresscs acute and chronic least 25% improvement in 4 measures) were also better inflammation, including arthritis, in several animal mod- in the GLA treatment group (14 of 22 patients versus 4 els (8). In a randomized, placebo-controlled trial of 6 of 19 in the placebo group; P = 0.015). During the months' duration in a small numbcr of rheumatoid second 6 months, both groups exhibited improvement in arthritis (pA)patients, 1.4 gdday of GLA in borage disease activity. Thus, patients taking GLA during the seed oil reduced synovitis in a statistically and clinically entire study showed progressive improvement during significant manncr (9), which suggests that GLA is a the second 6 months. In this group, 16 of 21 patients potentially effectivc treatment for RA. Results of exper- showed meaningful improvement at 12 months com- iments in animals suggest that the antiinflammatory pared with study entry. effects of GLA arc dose dependent. Therefore, we Conclusion. GLA at doses used in this study is a carried out a 1-year trial of GLA treatment at a dosage well-tolerated and effective treatment for active RA. of 2.8 gm/day in patients with RA and activc synovitis to ~ .- ... - assess the clinical efficacy and tolcrability of GLA Supported in part by FDA grant FD-R-000756 and by NIH administered as the frce fatty acid. grant RO- 1-AR-38501. Robcrt B. Zurier. MD. Konald G. Kossctti. MPH. Eric W. Jacobson, MD. Dcborah M. DcMarco. MD, Nancy Y. Liu. MD, PATIENTS AND METHODS Joseph E. Temming, MD, Bernadette M. White. RN: University of Massachusetts Medical Center, Worcester; Michael Laposata. MD. Study design. The first portion of the study was a PhD: Massachusetts GCnfXdl Hospital, Boston. 6-month, randomized, double-blind comparison of GLA and Addrcss rcprint rcqucsts to Robcrt B. Zurier, MD. University of Massachusetts Medical Center, 55 Lake Avenue North, Worcester. placebo (sunflower seed oil) in RA patients with aclive syno- MA 01655-0335. vitis. During months 6-12, all patients were given <;LA. Submitted for publication February 21. 1996; accepted in Although the patients knew they were guaranteed at least 6 rcviscd form May 20, 1YY6. months of GLA during the 13-month trial, they did not know GAMMA-LINOLENIC ACID IN RA 1809 LlNOLElC ACID (182) DELTA-6 DESATURASE zI GAMMA LlNOLENlC ACID (183) ELONCASE COOH DELTA-5 DESATURASE DIHOMOGAMMA b LlNOLENlC ACID (203) ARACHIDONIC ACID (204) PGEI TXA 1 (150H)DCLA LTCJ Figure 1. Metabolic pathway of 06 fatty acids. The pathway is one of progressive desaturation, alternating with elongation (addition of 2 carbons). Numbers in parentheses represent the number of carbon atomsthe number of double bonds. PGE, = prostaglandin E,; TXA, = thromboxane A,; (15OH)DGLA = 15-hydroxydihomo-y- linolenic acid: LTC, = leukotriene C3. when that would occur. Also, during the second 6 months, the treated with any investigational drug within 1 month of entry, examining rheumatologist did not know which group the with commercially available fish or plant seed oil products patient had been in during the first 6 months. Patients were within 3 months of entry, or with an intraarticular injection of evaluated at 3-month intervals. GLA was stopped at 12 corticosteroids within 1 month of entry. months, and patients were evaluated again 3 months later (at Patients were randomized to receive either GLA 15 months). (GLA-70) or placebo capsules. GLA-70 (provided by Scotia The protocol was reviewed and approved by the Com- Pharmaceuticals Ltd., Guildford, Surrey, England) is produced mittee for the Protection of Human Subjects in Research at from borage seed oil, which is hydrolyzed, separated from the University of Massachusetts Medical Center and by the reactants and byproducts, and purified by washing with water. Food and Drug Administration. Written informed consent was After fractional crystallization, short-chain and saturated fatty obtained from each patient. acids are removed by filtration. The filtrate is distilled twice Eligibility. Patients were eligible to participate in the under vacuum, and the GLA is isolated in the distillate. study if they had KA according to the revised criteria of the GIA-70 contains -70% GLA as a percentage of the total fatty American College of Rheumatology (ACR; formerly, the acids; the other major fatty acids are linoleic acid (20%) and American Rheumatism Association) (lo), were between ages oleic acid (5%). The remaining 5% is made up of smaller 18 and 90, and were of functional class I, 11, or 111 (11). The quantities of the fatty acids present in borage seed oil. Each dosage of aspirin or other nonsteroidal antiinflammatory drug capsule contained 0.5 ml of oil and 13.6 IU of vitamin E, and (NSAID) and of corticosteroid (not to exceed 10 mg of provided 4.5 kcal daily. Vitamin E alone does not benefit RA prednisone or equivalent per day) had to be unchanged for 1 patients (12). The total daily dose (8 capsules) provided 2.8 gm month before study entry, and dosages of second-line drugs of GLA had to be stable and unchanged for 3 months before entry. All The placebo capsules, which were identical in appear- patients had active disease. as defined by the presence of at ance and color and were taken according to the same schedule least 3 of the following 4 criteria: 26 painful or tender joints; (4 capsules twice a day, after a meal), contained sunflower seed 23 swollen joints; morning stiffness of at least 45 minutes' oil (Scotia Pharmaceuticals Ltd.), which is 52% linoleic acid, duration; and a Westergren erythrocyte sedimentation rate 35% oleic acid, 6% palmitic acid, 6% stearic acid, and 1% (ESR) of at least 28 mm/hour. Medications required for other fatty acids. Neither the GLA-70 nor the placebo capsules coexisting medical conditions were permitted; these conditions had any taste. An excess of capsules was given, and the were mild and well controlled. Patients were instructed to capsules were counted at each visit to monitor compliance. maintain their typical diet. GLA was administered under an Investigational New Drug Patients were ineligible for the study if they had beeti Approval (#28867) issued to one of the investigators (RHZ). 1810 ZURIER ET AL Clinical assessments. The patients, primary care phy- above): joint tenderness count or score, joint swelling count or sicians, referring rheumatologists, and study investigators were score, global assessment by physician, global assessment by unaware of the study group assignments. Assessments were patient, pain assessment by patient, duration of morning performed by 4 board-certified rheumatologists (EWJ, DMD, stiffness, and IIAQ score. NYL, and JET) with the aid of a nurse (BMW) in the Clinical Preparation of platelets. Blood was obtained by veni- Research Center at the University of Massachusetts .Medical puncture and collected in tubes containing EDTA. Platelet- Center. Two of the rheumatologists evaluated 44 of the 56 rich plasma was prepared by centrifugation of whole blood at patients who entered the study. Each patient’s condition was l0Og for 15 minutes at room temperature. Platelet counts were assessed by the same rheumatologist through the entire course performed in a hemocytometer. Aliquots (1 ml) of platelet-rich of the study to avoid inter-examiner variability. The primary plasma and of plasma were stored under nitrogen at -80°C outcome measure was the tender joint count as defined by the until fatty acid analyses were done. ACR (13). Fatty acid analysis. Lipids from each sample were The referring rheumatologist continued to manage the extracted and methylatcd as described by Lepage and Roy patient’s RA. Medication dosages could be reduced, but any (19). The mixture of fatty acid methyl esters was analyzed by increase in the medication for RA or any change in or addition electron-impact gas chromatography/mass spectroscopy using of a drug was a protocol violation.