Joshi R, Arora V, Desjardins JP, Robinson D, Himmelstein KJ, Iversen PL. In vivo properties of an in situ forming gel for parenteral delivery of macromolecular drugs.
Pharm Res 1998;
15:1189-95. [PMID:
9706048 DOI:
10.1023/a:1011979505697]
[Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
PURPOSE
This study characterizes the in vivo properties of an in situ forming gel, comprising of IPC of water-soluble polymers, PMA and PEG, for sustained release of macromolecular drugs.
METHODS
40, 50, or 60% w/v formulations were injected subcutaneously in a rat model either alone, or containing model macromolecules, 3A2-ATG-psODN or REV-psODN, to (i) determine the approximate gelling and residence time of the gel at the site of injection (ii) assess the biological efficacy of the formulation using a MZ sleep time model and (iii) demonstrate specificity of the sequence and selectivity of the psODNs by measuring changes in microsomal enzyme levels and urine volumes.
RESULTS
A sol to gel transition requires 15 min in vivo, and the 60% w/v IPC gel remains at the site of injection for up to 72 hr. The MZ sleep times and CYP3A2 expression due to 3A2-ATG-psODNs released from the gel are significantly different compared to that of REV-psODNs.
CONCLUSIONS
The IPC solutions exhibit phase transformation in vivo. and demonstrate no evidence of toxicity. The pharmacological effects observed from the of release of 3A2-ATG-psODNs suggest that the formulation can entrap, protect, and sustain the delivery of macromolecules. .
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