Table 4:

Preclinical Microparticle Systems

Polymer/ Drug/ Formulation	Model	Dosing Scheme (Dose)	Outcome	Ref.
PEA/ CXB/ MP	Rat ACLT/MMx model	Single injection (14.6 μg CXB)	PEA-CXB was detectable at 12 weeks but did not improve histological outcomes	[145]
PEA/ CXB/ MP	Rat ACLT/MMx model	Single injection (15, 115, 195 μg CXB)	PEA-CXB significantly improved bone outcomes independent of CXB dose; OARSI score was not improved	[146]
PEA/ TCA/ MP	Rat collagenase-induced model	Single injection (250 μg TCA)	PEA-TCA was detectable at 10 weeks and improved synovitis scores at 7 weeks.	[148]
PEA or PLGA/ TCA/ MP	Rat synovitis model	Single injection (62.5 μg TCA)	PEA-TCA significantly reduced joint swelling after second and third flares; PLGA-TCA did not; PEA-TCA significantly improved synovitis after the third flare	[149]
PLA-TGPS/ PH/ NPPs	Mouse DMM model	Injection on days 7 and 35 (2.5 mg/kg)	PH-NPPs significantly improved OARSI score and reduced serum cytokines at 9 weeks	[150]
PLA-TGPS/ KGN/ NPPs	Mouse DMM model	Injection on days 7 and 36 (2.25 mg/kg)	KGN-NPPs significantly improved OARSI score at day 63	[152]

Abbreviations: ACLT=anterior cruciate ligament transection; CXB=celecoxib; DMM=destabilization of the medial meniscus; KGN=kartogenin; MMx=medial meniscectomy; MP=microparticle; NPP=nanocrystal-polymer particle; OARSI=Osteoarthritis Research Society International; PEA=poly(ester amide); PH=PH-797804; PLA=poly(lactic acid); PLGA=poly(lactic-co-glycolic acid); TCA=triamcinolone acetonide; TGPS= D-α-tocopherol PEG 1000 succinate