Abstract: Compositions containing biologically active molecules encapsulated in self-assembling, diketopiperazine microspheres (TECHNOSPHEREs™) and methods for making and administering such compositions are described herein. The compositions can be used to immunize individuals against agents of biological warfare. The biologically active molecules include atropine, antibodies, antigens, and antibiotics. The compositions can be placed in an inhalation device for self-administration. Pulmonary delivery of TECHNOSPHERE™ encapsulated atropine, antibodies, vaccines, and antibiotics provides an accelerated onset of immunity to the targeted disease. Furthermore, the TECHNOSPHERE™ encapsulated atropine, antibodies, vaccines, and antibiotics are stable formulations, suitable for stockpiling, rapid dissemination and mass treatment.

Abstract: Methylphenidate or other drugs are provided in a formulation for oral administration that releases the drug in two or more pharmacokinetic spikes, by combining different release forms in a single formulation. In a preferred embodiment for methylphenidate, the first pharmacokinetic spike is achieved by the release of taste-masked methylphenidate which is not enterically coated, while a second pharmacokinetic spike is achieved by the release of methylphenidate in a finely divided form from enterically coated pellets or microparticles formulated for rapid release following dissolution of the enteric coating. A critical aspect of the formulation is the inclusion of excipients that create a burst release following the initial rapid release and uptake. The formulation can be administered as a paste, jelly, suspension, or fast dissolving wafer. To manipulate the dose, the formulation can be provided, for example, as a paste packaged in a tube similar to those used to dispense toothpaste.

Abstract: Drug delivery to the pulmonary system has been achieved by encapsulation of the drug to be delivered in microparticles having a size range between 0.5 and ten microns, preferably in the range of two to five microns, formed of a material releasing drug at a pH of greater than 6.4. In a preferred embodiment, the drug delivery system is based on the formation of diketopiperazine microparticles which are stable at a pH of 6.4 or less and unstable at pH of greater than 6.4, or which are stable at both acidic and basic pH, but which are unstable at pH between about 6.4 and 8. Other types of materials can also be used, including biodegradable natural and synthetic polymers, such as proteins, polymers of mixed amino acids (proteinoids), alginate, and poly(hydroxy acids). In another embodiment, the microparticles have been modified to effect targeting to specific cell types and to effect release only after reaching the targeted cells.

Abstract: Methods are provided for purifying peptides and proteins by incorporating the peptide or protein into a diketopiperazine or competitive complexing agent to facilitate removal one or more impurities, i.e. undesirable components, from the peptide or protein. In a preferred embodiment, a peptide, such as insulin, containing one or more impurities, e.g., zinc ions, is entrapped in diketopiperazine to form a precipitate of peptide/diketopiperazine/impurity, which is then washed with a solvent for the impurity to be removed, which is a nonsolvent for the diketopiperazine and a nonsolvent for the peptide. Formulations and methods also are provided for the improved transport of active agents across biological membranes, resulting for example in a rapid increase in blood agent concentration.

Abstract: Improved methods for forming fine particles of a material have been developed, wherein the method steps include dissolving the material in a solvent to form a dilute solution, immobilizing the dilution solution, and then removing the solvent to yield particles of the material. Methods of immobilizing the dilute solution include freezing, gelation, and chelation. In a preferred embodiment, the immobilized solvent is removed by lyophilization, i.e. reducing the ambient pressure while avoiding application of sufficient heat to power a phase transition. Essentially any material and solvent for the material can be used in the methods described herein. Proteins and peptides in an aqueous solvent are the preferred systems.

Abstract: Methods are provided for purifying peptides and proteins by incorporating the peptide or protein into a diketopiperazine or competitive complexing agent to facilitate removal one or more impurities, i.e. undesirable components, from the peptide or protein. In a preferred embodiment, a peptide, such as insulin, containing one or more impurities, e.g., zinc ions, is entrapped in diketopiperazine to form a precipitate of peptide/diketopiperazine/impurity, which is then washed with a solvent for the impurity to be removed, which is a nonsolvent for the diketopiperazine and a nonsolvent for the peptide. Formulations and methods also are provided for the improved transport of active agents across biological membranes, resulting for example in a rapid increase in blood agent concentration.

Abstract: Improved methods for forming fine particles of a material have been developed, wherein the method steps include dissolving the material in a solvent to form a dilute solution, immobilizing the dilution solution, and then removing the solvent to yield particles of the material. Methods of immobilizing the dilute solution include freezing, gelation, and chelation. In a preferred embodiment, the immobilized solvent is removed by lyophilization, i.e. reducing the ambient pressure while avoiding application of sufficient heat to power a phase transition. Essentially any material and solvent for the material can be used in the methods described herein. Proteins and peptides in an aqueous solvent are the preferred systems.

Abstract: Drug delivery to the pulmonary system has been achieved by encapsulation of the drug to be delivered in microparticles having a size range between 0.5 and ten microns, preferably in the range of two to five microns, formed of a material releasing drug at a pH of greater than 6.4. In a preferred embodiment, the drug delivery system is based on the formation of diketopiperazine microparticles which are stable at a pH of 6.4 or less and unstable at pH of greater than 6.4, or which are stable at both acidic and basic pH, but which are unstable at pH between about 6.4 and 8. Other types of materials can also be used, including biodegradable natural and synthetic polymers, such as proteins, polymers of mixed amino acids (proteinoids), alginate, and poly(hydroxy acids). In another embodiment, the microparticles have been modified to effect targeting to specific cell types and to effect release only after reaching the targeted cells.

Abstract: Methylphenidate or other drugs are provided in a formulation for oral administration that releases the drug in two or more pharmacokinetic spikes, by combining different release forms in a single formulation. In a preferred embodiment for methylphenidate, the first pharmacokinetic spike is achieved by the release of taste-masked methylphenidate which is not enterically coated, while a second pharmacokinetic spike is achieved by the release of methylphenidate in a finely divided form from enterically coated pellets or microparticles formulated for rapid release following dissolution of the enteric coating. A critical aspect of the formulation is the inclusion of excipients that create a burst release following the initial rapid release and uptake. The formulation can be administered as a paste, jelly, suspension, or fast dissolving wafer. To manipulate the dose, the formulation can be provided, for example, as a paste packaged in a tube similar to those used to dispense toothpaste.

Abstract: Drug delivery to the pulmonary system has been achieved by encapsulation of the drug to be delivered in microparticles having a size range between 0.5 and ten microns, preferably in the range of two to five microns, formed of a material releasing drug at a pH of greater than 6.4. In a preferred embodiment, the drug delivery system is based on the formation of diketopiperazine microparticles which are stable at a pH of 6.4 or less and unstable at pH of greater than 6.4, or which are stable at both acidic and basic pH, but which are unstable at pH between about 6.4 and 8. Other types of materials can also be used, including biodegradable natural and synthetic polymers, such as proteins, polymers of mixed amino acids (proteinoids), alginate, and poly(hydroxy acids). In another embodiment, the microparticles have been modified to effect targeting to specific cell types and to effect release only after reaching the targeted cells.

Abstract: Muscarinic M.sub.2 receptor ligands are described which are suitable for the treatment of neurological disorders, and which may be administered with minimal side-effects. A method of synthesis of these compounds is also described.

Abstract: Conjugates of fluorescent labels with specific, selective, and high affinity ligands for receptors have been synthesized and used to directly measure binding to receptors.

Abstract: Drug delivery systems have been developed based on the formation of diketopiperazine (or analogs) microparticles. In the preferred embodiment the microparticle is stable at low pH and disintegrates at physiological pH, and is particularly useful for oral drug delivery. In other embodiments, the microparticles are stable at high pH and disintegrate at neutral or basic pH, or are stable at neutral pH and disintegrate at high or low pH. In the most preferred embodiment the microparticles are formed in the presence of the drug to be delivered, for example, insulin, felbamate, calcitonin or heparin. The diketopiperazine synthetic intermediates are preferably formed by cyclodimerization to form diketopiperazine derivatives at elevated temperatures under dehydrating conditions, functionalized on the side chains, and then precipitated with drug to be incorporated into microparticles.

Abstract: Conjugates of fluorescent labels with specific, selective, and high affinity ligands for receptors have been synthesized and used to directly measure binding to receptors. In the examples, fluorescein conjugates of the high-affinity benzodiazepine receptor ligands Ro 15-1788 and Ro 7-1986 were synthesized. The binding of these fluorescent ligands (BD 621, BD 623 and BD 607) to benzodiazepine receptors was characterized by direct fluorescence measurement. Both the equilibrium dissociation constants (K.sub.D) of BD 621 and BD 607 and the maximum number of binding sites (B.sub.max) estimated by fluorescence monitoring were consistent with values obtained by using radioligand binding techniques. The binding of BD 621 and BD 607 assessed by fluorescence measurement was reversible, abolished by photoaffinity labeling with Ro 15-4513, and unaffected by a variety of substances that do not bind to benzodiazepine receptors.

Abstract: Drug delivery systems have been developed based on the formation of diketopiperazine (or analogs) microparticles. In the preferred embodiment the microparticle is stable at low pH and disintegrates at physiological pH, and is particularly useful for oral drug delivery. In the most preferred embodiment the microparticles are formed in the presence of the drug to be delivered, for example, insulin or heparin. The diketopiperazine synthetic intermediates are preferably formed by cyclodimerization to form diketopiperazine derivatives at elevated conditions under dehydrating conditions, then precipitated with drug to be incorporated into microparticles.