166HOLMIUM-PHYTATE-RADIOSYNOVIORTHESIS IN RHEUMATOID ARTHRITIS. FIRST CLINICAL RESULTS

Background: The traditional isotopes cause whole body radiation of 10 Rad. Isotope specialists have aspired to produce an isotope incurring lower radiation loads.166-Holmium-phytate produced by us: radiation type beta energy maximum: 1,84 MeV; radiation type gamma energy maximum: 0,66 MeV; soft tissue penetration: maximum 8,4 mm; average: 3,3 mm; half-life: 26,9 hours; particle size: 0,6-2 micromObjectives: Examination of anti-inflammatory effect of 166-Holmium-phytate injection.Methods: Phases III, prospectiv study. 32 patients suffering from chronic synovitis, rheumatoid arthritis were examined. The protocol commenced with screening. The patients were selected according to inclusion and exclusion criteria.Holmium phytate injectable suspension marked by 600 MBq 166Holmium phytate injectable suspension, and 40 mg of 1 ml triamcinolone acetonide and 1 ml of lidocaine 1%There were 12 month follow-up period after the administration of the isotope.Inflammatory activity of the affected knee-joint was tested prior to treatment, and the 3th and 3, 6 and 12 months after treatment. Evaulation was based on the criteria as described by Müller, Rau and Scütte the score system was developed by the authors.Results: During the study period, inflammation decreased. In the first half years excellent and good results were recorded in 93.3%. One year after radiosynoviorthesis 93.3% of patients did not need another punction. Administration of Holmium-166 phytate is a safe procedure. We did not detect any symptoms of radiation sickness. We found no deviations in either haematological or chemical parameters during the study period.Conclusion: Holmium-166 isotope is an effective radiopharmacy treating synovitis. Due its adventageous features it produces less radioactive damage on the organism than the traditionally used isotopes (90-Yttrium, 169-Erbium, 186-Rhenium). Due to its physical parameters it is optimal to treat large joints (knee) and medium size joints (hips, shoulder, elbow, wrist, ankle). Effective dosage is 555-925 MBq.References: 1. Margit Szentesi: Radiosynoviorthesis with Ho-166 phytate. First clinical results EANM Post-Congress Scintific Meeting. Radionuclide therapy in theory and practice. Győr, Hungary. 5. September. 2002.2. Szentesi M., Környei J., Antalffy M., Törkő J. Tóth Gy., Jánoki Gy., Balogh L.,: Study of intraarticular application of 166-Holmium IHPP in rabbits. World Journal of Nucl. Med. 1. Suppl. 2. S243. September, 2002.3. Szentesi M., Takács S., Farbaki Zs., Nagy E.,1 Környei J., Antalffy M., Törkő J., Tóth Gy., Jánoki Gy., Balogh L. Géher P., Comparitive study of applying increasing doses of 166Ho- phytate injectable suspension in chronic synovitis. (Comparative, randomized, single-blind, placebo-controlled study with increasing dosage) Eur. J. Nucl. Med. Suppl. 2. 498. 2003.4. Szentesi M., Takács S., Farbaki Zs., Nagy E., Környei J., Antalffy M., Törkő J. Tóth Gy., Jánoki Gy., Balogh L., Géher P.: Radiosynoviorthesis with 166Ho-phytate - First clinical results Phase I-IIa, randomized, increasing dosage, single-blind, placebo-controlled comparative study. Eur. J. Nucl. Med. Suppl. 2. 500. 2003.5. Szentesi M., Farbaky Zs., Budai I., Bálint B., Géher Pál.: Monitoring the synovial thickness after 166-Holmium-phytate radiosynoviorthesis by sonography. Nuclearmedicin: 2003. 42. 179-180.Citation: Ann Rheum Dis, volume 64, supplement III, year 2005, page 440Session: Rheumatoid Arthritis – Treatment