Treatment of adjuvant-induced arthritis rats with a macromolecular prodrug of dexamethasone. The treatment of adjuvant-induced arthritis (AA) rats (eight rats/group) with acid-labile N-(2-hydroxypropyl)methacrylamide (HPMA) copolymer-dexamethasone conjugate (P-Dex), half-dose P-Dex, free dexamethasone (Dex), HPMA polymer without Dex (PHPMA) and saline were summarized in this figure. An untreated healthy control group was also included. (a) Changes in AA rat ankle diameters during the treatment. (b) Changes in articular index score of the animals during the treatment. (c) Endpoint bone mineral density (BMD) of the ankle joints for all the animal groups. (d) Average histology scores of the ankle joints from the six animal groups. ***P < 0.001, **P < 0.01, *P < 0.05; ns, not significant.