TY - JOUR
T1 - Safe and sustained vaginal delivery of pyrimidinedione HIV-1 inhibitors from polyurethane intravaginal rings
AU - Johnson, Todd J.
AU - Srinivasan, Priya
AU - Albright, Theodore H.
AU - Watson-Buckheit, Karen
AU - Rabe, Lorna
AU - Martin, Amy
AU - Pau, Chou Pong
AU - Hendry, R. Michael
AU - Otten, Ron
AU - McNicholl, Janet
AU - Buckheit, Robert
AU - Smith, James
AU - Kiser, Patrick F.
PY - 2012/3
Y1 - 2012/3
N2 - The potent antiretroviral pyrimidinediones IQP-0528 (PYD1) and IQP-0532 (PYD2) were formulated in polyurethane intravaginal rings (IVRs) as prophylactic drug delivery systems to prevent the sexual transmission of HIV-1. To aid in the selection of a pyrimidinedione candidate and the optimal loading of the drug in the IVR delivery system, four pyrimidinedione IVR formulations (PYD1 at 0.5 wt% [PYD1 0.5wt%], PYD1 1wt%, PYD2 4wt%, and PYD2 14wt%) were evaluated in pigtail macaques over 28 days for safety and pyrimidinedione vaginal biodistribution. Kinetic analysis of vaginal proinflammatory cytokines, native microflora, and drug levels suggested that all formulations were safe, but only the high-loaded PYD2 14wt% IVR demonstrated consistently high pyrimidinedione vaginal fluid and tissue levels over the 28-day study. This formulation delivered drug in excess of 10μg/ml to vaginal fluid and 1μg/g to vaginal tissue, a level over 1,000 times the in vitro 50% effective concentration. The in vitro release of PYD1 and PYD2 under nonsink conditions correlated well with in vivo release, both in amount and in kinetic profile, and therefore may serve as a more biologically relevant means of evaluating release in vitro than typically employed sink conditions. Lastly, the pyrimidinediones in the IVR formulation were chemically stable after 90 days of storage at elevated temperature, and the potent nanomolar-level antiviral activity of both molecules was retained after in vitro release. Altogether, these results point to the successful IVR formulation and vaginal biodistribution of the pyrimidinediones and demonstrate the usefulness of the pigtail macaque model in evaluating and screening antiretroviral IVR formulations prior to preclinical and clinical evaluation.
AB - The potent antiretroviral pyrimidinediones IQP-0528 (PYD1) and IQP-0532 (PYD2) were formulated in polyurethane intravaginal rings (IVRs) as prophylactic drug delivery systems to prevent the sexual transmission of HIV-1. To aid in the selection of a pyrimidinedione candidate and the optimal loading of the drug in the IVR delivery system, four pyrimidinedione IVR formulations (PYD1 at 0.5 wt% [PYD1 0.5wt%], PYD1 1wt%, PYD2 4wt%, and PYD2 14wt%) were evaluated in pigtail macaques over 28 days for safety and pyrimidinedione vaginal biodistribution. Kinetic analysis of vaginal proinflammatory cytokines, native microflora, and drug levels suggested that all formulations were safe, but only the high-loaded PYD2 14wt% IVR demonstrated consistently high pyrimidinedione vaginal fluid and tissue levels over the 28-day study. This formulation delivered drug in excess of 10μg/ml to vaginal fluid and 1μg/g to vaginal tissue, a level over 1,000 times the in vitro 50% effective concentration. The in vitro release of PYD1 and PYD2 under nonsink conditions correlated well with in vivo release, both in amount and in kinetic profile, and therefore may serve as a more biologically relevant means of evaluating release in vitro than typically employed sink conditions. Lastly, the pyrimidinediones in the IVR formulation were chemically stable after 90 days of storage at elevated temperature, and the potent nanomolar-level antiviral activity of both molecules was retained after in vitro release. Altogether, these results point to the successful IVR formulation and vaginal biodistribution of the pyrimidinediones and demonstrate the usefulness of the pigtail macaque model in evaluating and screening antiretroviral IVR formulations prior to preclinical and clinical evaluation.
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U2 - 10.1128/AAC.05721-11
DO - 10.1128/AAC.05721-11
M3 - Article
C2 - 22155820
AN - SCOPUS:84863173866
VL - 56
SP - 1291
EP - 1299
JO - Antimicrobial Agents and Chemotherapy
JF - Antimicrobial Agents and Chemotherapy
SN - 0066-4804
IS - 3
ER -