| Abstract | Faktor tumorske nekroze alfa prepoznat je kao glavni regulator upalnog odgovora, ali i kao pro-upalni citokin uključen u patogenezu nekih autoimunih bolesti. Iz tog razloga stvoreni su antagonisti TNF-α. Farmakokinetička varijabilnost, nuspojave vezane uz koncentraciju lijeka i uski terapijski raspon čine terapijsko praćenje koncentracije ovih lijekova korisnim u kliničkoj praksi.
U ovome radu opisan je postupak verifikacije kvantitativne imunonefelometrijske metode N Latex aTNFα (Siemens Healthineers) za određivanje lijekova adalimumaba i infliksimaba na potpuno automatiziranom analizatoru Atellica® NEPH 360 (Siemens Healthineers) u uzorku seruma. Verifikacija je obuhvatila ispitivanje preciznosti koristeći kontrolne uzorke proizvođača, usporedbu s enzimskim imunokemijskim testom RIDASCREEN ADA/IFX Monitoring (R-Biopharm AG) te provjeru granice kvantifikacije. Verifikacija je provedena u Zavodu za kliničku kemiju, KBC Sestre milosrdnice u Zagrebu.
Postupak je obuhvatio 66 uzorka seruma pacijenata u kojima je zatražena kvantifikacija ADA (N = 33) ili INF (N = 33). Ponovljivost i unutarlaboratorijska nepreciznost za određivanje ADA iznosi 5,0 % i 5,4 % za visoku razinu te 4,6 % i 4,7 % za nisku razinu kontrola, dok za određivanje INF iznosi 7,2 % i 6,1 % za visoku razinu te 4,5 % i 4,0 % na nisku razinu kontrole. Usporedba metoda je potvrdila da ne postoji proporcionalno ni konstanto odstupanje između metoda. Regresijskom analizom dobivena je jednadžba y = -0,095 (95%CI -0,148– 0, 092) + 0,995 (95%CI 0,881– 1,053) za ADA, dok za INF y = -0,062 (95%CI -0,381 – 0,439) + 0,958 (95%CI 0,834 – 1,107). Bland-Altman analiza potvrdila da je da ne postoji statistički značajno konstantno niti proporcionalno odstupanje. Provjerom LoQ potvrđeni su deklarirane vrijednosti proizvođača pri određivanju ADA (0,37 mg/L) i INF (0,39 mg/L). Rezultati verifikacije su potvrdili prikladnost ispitivane metode pri kvantitativnom određivanju ADA i INF. |
| Abstract (english) | Tumor necrosis factor alpha is recognized as the main regulator of the inflammatory response, but also as a pro-inflammatory cytokine involved in the pathogenesis of some autoimmune diseases. For this reason, TNF-α antagonists were designed. Pharmacokinetic variability, drug concentration-related side effects and a narrow therapeutic range make therapeutic concentration monitoring of these drugs useful in clinical practice.
This thesis describes the verification procedure of the quantitative immunonephelometric method N Latex aTNFα (Siemens Healthineers) for the measurement of the drugs adalimumab and infliximab on the automated analyzer Atellica® NEPH 360 (Siemens Healthineers) in a serum sample. The verification included teh study of precision using quality control samples, comparison with the enzyme immunochemical test RIDASCREEN® ADA/IFX Monitoring (R-Biopharm AG) and a study of the limit of quantification. The verification was carried out at the Department of Clinical Chemistry, Sestre milosrdnice University Hospital Center, Zagreb.
The procedure included 66 serum samples from patients in whom ADA (N = 33) or INF (N = 33) quantification was requested. Repeatability and within-laboratory imprecision for the determination of ADA was 5.0% and 5.4% for the high level QC and 4.6% and 4.7% for the low level QC, while for the determination of INF was 7.2% and 6.1% for the high level QC and 4.5% and 4.0% to a low level QC. The comparison of the methods confirmed that there is no proportional or constant deviation between the methods. Regression analysis yielded the equation y = -0.095 (95%CI -0.148– 0. 092) + 0.995 (95%CI 0.881– 1.053) for ADA, while for INF y = -0.062 (95%CI -0.381 – 0.439) + 0.958 (95%CI 0.834 – 1.107). Bland-Altman analysis confirmed there is no statistically significant constant nor proportional deviation. The LoQ study confirmed the manufacturer declared values for ADA (0.37 mg/L) and INF (0.39 mg/L). The verification results confirmed the suitability of the tested method for the quantitative determination of ADA and INF. |
