Other

US Government As Represented by the Secretary of the Army

University of Miami

Research Triangle Pharmaceuticals

Duncan H Haynes

Mark D Kline

Ben H Bodeker

Yeon S Ahn

Wenche Jy

William J Harrington, Jr

A surgical implant or external wound dressing which functions as both a hemostat and a device to safely and effectively deliver any of a number of pharmaceuticals to targeted tissue at a controlled rate is disclosed. The device generally comprises a carrier in the form of fibers, sutures, fabrics, cross-linked solid foams or bandages, a pharmaceutical in solid micoparticulate form releasably bound to the carrier fibers, and a lipid adjuvant which aids the binding of the microparticles to the fibers as well as their function in the body.

Drug releasing surgical implant or dressing material

Formulations of phospholipid-coated microdroplets of propofol devoid of fats and triglycerides provide chronic sedation over extended periods of time without fat overload. Being free of nutrients that support bacterial growth, these microdroplet formulations are bacteriosatic and bactericidal (e.g. self-sterilizing) and thus have extended shelf life.

Propofol microdroplet formulations

The novel uses of the phospholipid-coated microcrystal in the delivery of water-soluble biomolecules such as polypeptides and proteins. The proteins are rendered insoluble by complexation and the resulting material forms the solid core of the phospholipid-coated particle. Alternatively, the proteins, bio-molecules or drugs can be entrapped in water-soluble form between the membranous layers of the coated microcrystal. All types of phospholipid microcrystals can incorporate 5 nm to 10 um diameter iron oxide particles to allow for manipulation by magnetic fields. Water-soluble bio-molecules including proteins, peptides, and drugs can be entrapped and retained with long shelf life in liposomes at high concentrations, provided that the phospholipid concentration is greater than 10% (w/v) such that greater than 50% of the system volume is enclosed within phospholipid membranes. Both the phospholipid-coated microcrystal and the phospholipid-coated microdroplet can be used as vaccine adjuvants.

Sustained release delivery of water-soluble bio-molecules and drugs

Water-insoluble drugs are rendered injectable by formulation as aqueous suspensions of phospholipid-coated microcrystals. The crystalline drug is reduced to 50 nm to 10 um dimensions by sonication or other processes inducing high shear in the presence of phospholipid or other membrane-forming amphipathic lipid. The membrane-forming lipid stabilizes the microcrystal by both hydrophobic and hydrophilic interactions, coating and enveloping it and thus protecting it from coalescence, and rendering the drug substance in solid form less irritating to tissue. Additional protection against coalescence is obtained by a secondary coating by additional membrane-forming lipid in vesicular form associated with and surrounding but not enveloping the lipid-encapsulated drug particles. Tissue-compatible formulations containing drug in concentrations up to 40% (w/v) are described. The preparations can be injected intra-lesionally and in numerous other sites, including intra-venous, intra-arterial, intra-muscular, intra-dermal, etc. The disclosure describes examples of formulations and pharmacokinetic data with antibiotics, anthelmintic drugs, antiinflammatory drugs, local and general anesthetics, and biologicals.

Phospholipid-coated microcrystals: injectable formulations of

Water-insoluble drugs are rendered injectable by formulation as aqueous suspensions of phospholipid-coated microcrystals. The crystalline drug is reduced to 50 nm to 10 .mu.m dimensions by sonication or other processes inducing high shear in the presence of phospholipid or other membrane-forming amphipathic lipid. The membrane-forming lipid stabilizes the microcrystal by both hydrophobic and hydrophilic interactions, coating and enveloping it and thus protecting it from coalescence, and rendering the drug substance in solid form less irritating to tissue. Additional protection against coalescence is obtained by a secondary coating by additional membrane-forming lipid in vesicular form associated with and surrounding but not enveloping the lipid-encapsulated drug particles. Tissue-compatible formulations containing drug in concentrations up to 40% (w/v) are described. The preparations can be injected intra-lesionally and in numerous other sites, including intra-venous, intra-arterial, intra-muscular, intra-dermal, etc. The disclosure describes examples of formulations and pharmacokinetic data with antibiotics, anthelmintic drugs, anti-inflammatory drugs, local and general anesthetics, and biologicals.

Calcium (Ca.sup.2+) channel blockers, such as nifedipine and verapamil, are used in the treatment of thromboembolic diseases such as stroke and peripheral vascular occlusive diseases, especially arterial and venous thrombosis, vasculitis, myelofibrosis disease and hemolytic anemias. Such diseases arise from platelet hyperactivation and the Ca.sup.2+ channel blockers restore the platelets to their normal aggregation characteristics. Diagnostic procedures for detecting platelet hyperactivation and defective calcium handling/transport indicative of certain peripheral obstructive diseases using chlorotetracycline as a detectable fluorescent probe as a means of assessing a patient's response to Ca.sup.2+ channel blockers in the therapy of such diseases are also described.

Method of treating diseases arising from platelet hyperactivation

Microdroplets of water-insoluble drugs coated with a phospholipid are prepared by sonication. As an example, microdroplets of the general anesthetic methoxyfluorane coated by a unimolecular layer of dimysistoyl phosphatidylcholine are prepared by sonication. The microdroplets so prepared remain stable in physiologically-compatible solution, and are suitable for injection, typically intradermally or intraveneously, into a patient for inducing local anesthesia. These methoxyflurane-containing microdroplets have been demonstrated to cause long-term local anesthesia when injected intradermally, giving duration of anesthesia 28 times longer than with other anesthetics, such as lidocaine and 11 times longer than with bupivacaine. The latter is considered longest acting conventional local anesthetic. The microdroplet is also capable of solubilizing and delivering benzocaine and other water-insoluble drugs, and thus represents a novel drug delivery system and general method for delivery of water-insoluble drugs, lowering the necessary dose and providing a more direct and timed release.

Microdroplets of water-insoluble drugs and injectable formulations

Local anesthesia is induced using microdroplets of a general anesthetic in liquid form. As an example, microdroplets of the general anesthetic methoxyfluorane coated by a unimolecular layer of dimysistoyl phosphatidylcholine are prepared by sonication. The microdroplets so prepared remain stable in physiologically-compatible solution, and are suitable for injection, typically intradermally or intraveneously, into a patient for inducing local anesthesia. These methoxyflurane-containing microdroplets have been demonstrated to cause long-term local anesthesia when injected intradermally, giving duration of anesthesia 28 times longer than with other anesthetics, such as lidocaine and 11 times longer than with bupivacaine.

Growing community of inventors

Miami, FL, United States of America

Duncan H Haynes