Previously, we demonstrated that a single prophylactic dose of SR-2P, a novel dual-component microbicide gel comprising acyclovir and tenofovir, led to a modest increase in mouse survival following a lethal challenge of herpes simplex virus 2 (HSV-2). Here, we show that a dose of SR-2P administered 24 h prior to infection provides some protection against the virus, but to a lesser degree than SR-2P administered either once a day for 2 days or 1 h prior to infection. None of the prophylactic doses blocked infection by the virus, and all resulted in 80 to 100% lethality.
View Article and Find Full Text PDFObjectives: Over-the-counter access to an inexpensive, effective topical microbicide could reduce the transmission of HIV and would increase women's control over their health and eliminate the need to obtain their partners' consent for prophylaxis. Chronic infection with herpes simplex virus 2 (HSV-2), also known as human herpes virus 2, has been shown to facilitate HIV infection and speed the progression to immunodeficiency disease. Our objective is to develop a drug formulation that protects against both HSV-2 and HIV infection and adheres to the vaginal surface with extended residence time.
View Article and Find Full Text PDFContext: Tuberculosis (TB) is a common and often deadly infectious disease caused by strains of Mycobacteria. Development of new anti-tubercular drugs is essential to control the emergence and severity of multidrug-resistant TB.
Objective: The objective of this study was to develop an oral preclinical liquid formulation of SQ641 and to determine the permeability across rat intestinal tissue by Ussing chamber.
The main objective of this investigation was to study the feasibility of developing a vaginal bioadhesive microbicide using a SRI's proprietary two-polymer gel platform (SR-2P). Several formulations were prepared with different combinations of temperature-sensitive polymer (Pluronic® F-127) and mucoadhesive polymer (Noveon® AA-1), producing gels of different characteristics. Prototype polymeric gels were evaluated for pH, osmolality, buffering capacity, and viscosity under simulated vaginal semen dilutions, and bioadhesivity using ex vivo mini pig vaginal tissues and texture analyzer.
View Article and Find Full Text PDFThe purpose of this research work is to evaluate toxicity of diethylenetriamine pentaacetic acid zinc trisodium salt (Zn-DTPA) tablets, a novel oral solid dosage form containing permeation enhancers in beagle dogs and Sprague Dawley rats. (Zn-DTPA) in tablet dosage form was administered once daily for 7 days to beagle dogs at low (840 mg/dog/day), mid (2520 mg/dog/day), or high (7560 mg/dog/day). On day 8, all treated and control groups were necropsied.
View Article and Find Full Text PDFObjective: To develop a tablet formulation for an active pharmaceutical ingredient for which sticking and filming problems occurred during tablet punching.
Methods: Direct compression and dry granulation tableting techniques were evaluated using factorial experimental design. The effects of chrome-coated punch tips, filler types and active percent in the tablet formulation by direct compression were evaluated.
The main objective of the present study was to develop formulations of noscapine hydrochloride hydrate with enhanced solubility and bioavailability using co-solvent- and cyclodextrin-based approaches. Different combinations of co-solvents, which were selected on the basis of high-throughput solubility screening, were subjected to in vitro intestinal drug permeability studies conducted with Ussing chambers. Vitamin E tocopherol polyethylene glycol succinate and propylene glycol based co-solvent formulations provided the maximum permeability coefficient for the drug.
View Article and Find Full Text PDFCancer Chemother Pharmacol
May 2011
Purpose: SR13668, a bis-indole with potent activity in vitro and in vivo against various cancers and promising cancer chemopreventive activity, was found to have very low oral bioavailability, <1%, in rats during pilot pharmacokinetic studies. The objective of these studies was to better understand the source of low oral exposure and to develop a formulation that could be used in preclinical development studies.
Methods: An automated screening system for determining solubility in lipid-based vehicles, singly and in combination, was used to identify formulations that might enhance absorption by improving solubility of SR13668, and these results were confirmed in vivo using Sprague-Dawley rats.
For a drug with low bioavailability, a matrix tablet with liquid permeation enhancer (Labrasol) was formulated. Factorial design was used to evaluate the effect of three formulation factors: drug percentage, polymer type (Methocel K100M or Eudragit L 100-55), and tablet binder percentage (Plasdone S-630) on tablet characteristics. Tablets were prepared by direct compression and characterized.
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