Pharmaceutical compositions comprising glucagon can be administered to control and treat diabetes while reducing or eliminating the risk of insulin-induced hypoglycemia. Also provided are methods of administering glucagon so as to reduce the risk of inducing hypoglycemia.

Description of the Invention

SUMMARY OF THE INVENTION

There remains a need for new methods for treating diabetes and new preparations of insulin and glucagon that reduce the risk of hypoglycemia induced by insulin therapy. The present invention meets this and other needs.

One aspect of the invention provides pharmaceutical compositions comprising both insulin and glucagon in amounts that can be administered to a diabetic patient not only to achieve therapeutically effective control of diabetes but also to prevent hypoglycemia. The formulations can include, for example, formulations suitable for injection, including by subcutaneous (s.c.) administration, formulations suitable for administration orally, formulations suitable for transdermal administration, formulations suitable for ocular administration, and formulations suitable for inhalation. In one embodiment, the compositions comprises between about 0.1 to 5 percent glucagon to insulin by weight for I.V. administration, or a dose equivalent amount for other methods of administration. In another embodiment, the compositions comprise about 0.5 to 2 percent glucagon to insulin by weight when the composition is for I.V. administration, or a dose equivalent amount for other methods of administration. For example, in some embodiments, the glucagon is administered subcutaneously ("s.c.") and 0.1% to 20% glucagon to insulin by weight is administered. In some embodiments, the composition is configured for s.c. administration and comprises 0.1-20 ng/kg/min. of glucagon to 2-20 units of insulin. In some embodiments, the composition is configured for s.c. administration and comprises sufficient glucagon for the administration of 5 to about 20 ng/kg/min. (e.g. more than 5 to 20 ng of glucagon for each kg of a person for each minute of effectiveness) of glucagon. In one embodiment, 5 to about 20 ng/kg/min. of glucagon is administered to 1-20 units of insulin. Administered ratios can be, for example, administered once an hour. In a preferred embodiment, the composition is suitable for administration of more 5 to about 20 ng/kg/min of glucagon for each 1-2 units of insulin administered. As will be appreciated, in some embodiments, the glucagon and insulin can be kept in separate containers and are not administered at the same time, but the appropriate ratios between the two are maintained. In one embodiment, the separate containers are contained in a single device suitable for administration of the glucagon and insulin, for example for administration subcutaneously; in another, two devices are used, one for each agent.

In another aspect, methods to treat diabetes in a human or other mammal without inducing or with a substantially reduced risk of inducing hypoglycemia are provided. In one embodiment, the composition comprising insulin and glucagon is administered to a patient before the symptoms of mild, moderate or severe hypoglycemia are present. In some embodiments, the methods of the invention are practiced to prevent nocturnal hypoglycemia in a Type I diabetic patient being treated with insulin therapy, including intensive insulin therapy. The methods comprise co-administration of insulin and glucagon, wherein said insulin is administered in amounts therapeutically effective for the control of diabetes, and said glucagon is administered in amounts therapeutically effective for the prevention of hypoglycemia, and wherein both insulin and glucagon are preferably administered simultaneously with one another or contemporaneously with one another, i.e., within about four hours of each other (as when regular, LISPRO, and ASPART insulins are used) or within about six to twelve hours of each other (as when longer acting insulins are used), and in any event prior to the onset of clinically observable hypoglycemia. In one embodiment, glucagon is administered before the insulin is administered. In another embodiment, insulin is administered before glucagon is administered. In one embodiment, the method involves maintaining the level of blood sugar above 70 mg/dL and below 180 mg/dL by the co-administration of insulin and glucagon to a diabetic patient. In another embodiment, the method involves administering glucagon s.c. in an amount between about 6 and 18 ng/kg per minute of glucagon. In one embodiment, 1-20 or 2-20 units of insulin are administered to a diabetic patient receiving glucagon in an amount between 6 and 18 ng/kg/min s.c. In another embodiment, the method involves administering between about 8 and 12 ng/kg per minute of glucagon s.c. In one embodiment, 0.1 to 2 or 2-20 units of insulin are administered to a diabetic patient receiving glucagon in an amount between 8 and 12 ng/kg/min. s.c. In another embodiment, the glucagon is administered by a means other than intravenously or subcutaneously, and a dose equivalent to the s.c. dosing provided above is administered.

In another aspect, methods to maintain blood glucose levels in a range that is neither hyperglycemic nor hypoglycemic are provided. These methods comprise the co-administration of insulin and glucagon.

In another aspect, glucagon formulations and modified glucagon suitable for co-administration with insulin in accordance with the present methods are provided.

In another aspect, kits are provided for preventing hypoglycemia. In one embodiment, the kits preferably include insulin, glucagon, and instructions for simultaneously administering the appropriate combination thereof.

In another aspect, the kits include insulin, a long acting form of glucagon, and instructions for use.

In some aspects, methods for restoring or preventing loss of hypoglycemic awareness or sensitivity is provided. The methods comprise administering an amount of glucagon to a patient over a period of time that is sufficient to prevent or restore hypoglycemic awareness to the patient. In one embodiment, the patient is administered insulin concurrently with the administration of glucagon.

In one aspect, a pharmaceutical formulation is provided that comprises insulin in an amount effective for the control of diabetes and glucagon in an amount effective for the prevention of hypoglycemia in a human or other mammal. The pharmaceutical formulation is configured to be administered subcutaneously and the ratio of insulin to glucagon is typically about 1 unit of insulin to between more than 40 milliunits to 200 milliunits of glucagon. In some embodiments, the amount of glucagon is between about 50 and 100 milliunits. In some embodiments, the glucagon is a longer-acting form of glucagon. In some embodiments, the longer-acting form of glucagon contains iodine. In some embodiments, the longer-acting form of glucagon contains zinc. In some embodiments, the longer-acting form of glucagon further comprises protamine.

In another aspect, methods of treating diabetes in a human or other mammal without inducing hypoglycemia are provided. The methods comprise administering insulin in an amount therapeutically effective for the control of diabetes. The insulin can be in an amount between 0.5 and 20 Units of insulin. The methods further comprise administering glucagon in a time and an amount therapeutically effective for the prevention of hypoglycemia. The glucagon can be administered subcutaneously and in an amount between more than 5 and less than or equal to 100 ng per kg of patient per minute of desired glucagon effectiveness. In some embodiments, the amount of glucagon administered is between 6 and 18 ng per kg of patient per minute of desired glucagon effectiveness. In some embodiments, the glucagon is a glucagon with a prolonged duration of action. In some embodiments, the glucagon is contained in a liposomal formulation. In some embodiments, the glucagon is contained in a microsphere. In some embodiments, one administers a formulation comprising both insulin and glucagon. In some embodiments, the insulin and glucagon are contained in a pump that controls administration of a drug to a patient. In some embodiments, the glucagon is administered simultaneously with insulin. In some embodiments, the ratio of glucagon to insulin is about more than 40 to 200 milliunits of glucagon to 1 unit of insulin. In some embodiments, 2 units of insulin are administered. In some embodiments, 10 units of insulin are administered and between 30 and 90 ng per kg per minute of glucagon are administered subcutaneously.

In another aspect, kits for the administration of glucagon and insulin in amounts to prevent hypoglycemia is provided. The kits comprise glucagon and insulin. The glucagon and insulin are in a ratio of 1-20 units of insulin to 32-480 milliunits of glucagon. The kits further comprise a means for administering glucagon subcutaneously and instructions for the administration of insulin and glucagon so that the glucagon prevents a hypoglycemic event. In some embodiments, the concentration of glucagon when completely dissolved in a glycerine solution is more than 500 micrograms per milliliter but less than 2000 micrograms per milliliter. In some embodiments, the glucagon and insulin are in a ratio of 1-3 units of insulin to 32-96 milliunits of glucagon. In some embodiments, the means for administering the glucagon subcutaneously is a pump and said pump is configured to deliver between about 6 to 20 ng/kg/minute of glucagon.

In another aspect, the use of glucagon in combination with insulin in the preparation of a medicament for treatment of diabetes is provided. Glucagon is used in an amount sufficient to prevent an onset of hypoglycemia, wherein a ratio of glucagon to insulin is between more than 40 micrograms and less than 500 micrograms of glucagon to 1-20 units of insulin. In some embodiments, the amount is sufficient to prevent an onset of hypoglycemia unawareness. In some embodiments, the amount of insulin is between 1 and 20 units and the amount of glucagon is between 41 and 200 milliunits. In some embodiments, a ratio of insulin to glucagon is about between 1 and 3 units of insulin to between more than 40 and less than or equal to about 96 milliunits glucagon. In some embodiments, the glucagon further comprises protamine.

DETAILED DESCRIPTION OF THE INVENTION

Methods and compositions are provided that can prevent, or significantly reduce the frequency and severity of, hypoglycemia in insulin-treated diabetic patients (both Type 1 and 2). In one aspect, the methods and compositions are employed to treat diabetes while regulating glucose levels above the levels of hypoglycemia. The methods and compositions can be used to replenish or restore the abnormally low glucagon responses often coincident with insulin administration, thereby preventing hypoglycemia.

One issue that complicates the prevention of hypoglycemia is that repeated hypoglycemic events can lead to a loss of hypoglycemic awareness; thus, even if initially detected by a patient, the patient's ability to identify hypoglycemic symptoms can be compromised or lost over time. Thus, compositions and methods that can prevent or reverse the loss of hypoglycemic awareness are desirable. One method by which this can be achieved is to administer glucagon, or another agent that elevates levels of blood glucose as described herein, in a relatively low dose over the time period in which insulin is to act to prevent the onset of mild hypoglycemia. This can also be used to reverse or prevent a loss of hypoglycemic awareness.

In one embodiment, the invention provides pharmaceutical formulations of two hormones, insulin and glucagon, that are combined in molar ratios that optimize glycemic management and attenuate the incidence of or prevent hypoglycemia. In another embodiment, methods and compositions for the simultaneous but separate administration of insulin and glucagon to achieve this benefit are provided. While the simultaneous administration of two hormones with activities viewed as counteracting would traditionally have appeared to have no beneficial effect, some of the present embodiments arise in part from the realization that such administration achieves the beneficial effect of preventing hypoglycemia by virtue of the buffering or blunting effects of glucagon without diminishing the beneficial effects of glucose regulation provided by insulin. In some embodiments, a low amount of glucagon is continuously administered to a patient that is, has, or is going to receive insulin. Thus, the use of a hyperglycemic agent, such as glucagon, to prevent the onset of hypoglycemia and its associated symptoms due to insulin administration, is contemplated. In some embodiments, a hyperglycemic agent, such as glucagon, is used to prevent the onset of iatrogenic hypoglycemia.

Thus, some of the embodiments provide a method for controlling diabetes with a reduced risk of hypoglycemia by simultaneous administration of insulin and glucagon to a diabetic patient. In one embodiment, a method of preventing hypoglycemia in a diabetic patient who is being treated with insulin and who is not suffering hypoglycemic symptoms is provided, comprising administering glucagon to the patient in an amount therapeutically effective for the prevention of hypoglycemia. In one embodiment, the glucagon is administered simultaneously with the insulin. In another embodiment, the glucagon is administered 10 minutes to hours before additional insulin is administered, and more preferably, 30 minutes to 60 minutes before additional insulin is administered. In other embodiments, the glucagon is administered within about one minute to about four hours after said patient has last been administered insulin. In one embodiment, the prevention of hypoglycemia comprises preventing the symptoms associated with hypoglycemia from becoming evident in a subject. In another embodiment, the prevention of hypoglycemia is achieved through maintaining an average blood glucose level of a subject above about 70 mg/dL, or above about 50-60 mg/dL. Preferably the blood glucose level of the subject is maintained under about 140-200 and at least under about 350 mg/dL. Preferably, the subject's blood glucose level is maintained so that normoglycemia is maintained.

As will be apparent to one of skill in the art upon consideration of the disclosure herein, any of the many different forms of insulin, as well as any of the many different routes of administration of insulin, including those both approved by the FDA and in development, can be used in the presently disclosed methods and formulations. Moreover, any of the currently available formulations of glucagon can similarly be used in the methods and formulations. However, because glucagon has been, prior to the present disclosure, administered only parenterally to control hypoglycemia, the present disclosure provides new glucagon derivatives, new formulations of glucagon and glucagon derivatives, and methods of administering glucagon and glucagon derivatives that are particularly suited to achieve the benefits provided by some of the present embodiments, including delayed and/or extended action glucagon.

While the precise dosage of insulin and glucagon will vary from patient to patient and depend upon a variety of factors, including but not limited to age and sex of the patient, type and severity of diabetes, past history of the patient, including hypoglycemic and hyperglycemic episodes, type of insulin and glucagon employed, and the like, the dosage for any patient can be determined, in light of the present disclosure, by one of skill in the art. The beneficial effects of some of the embodiments can generally be achieved by administering both insulin and glucagon in the ratio of about 1 unit of Insulin to about 0.02-40 milliunits of glucagon (0.02 to 40 micrograms), when the glucagon is administered I.V. A unit of insulin is defined as the term is typically used for the treatment of diabetes, e.g. approximately 34.2 micrograms to approximately 40 micrograms. The amount of insulin can also be measured in international units (IU). A unit of glucagon corresponds to 1 milligram of glucagon. In one embodiment, the ratio is 1 unit of insulin to 0.2 to 4.0 milliunits of glucagon (0.2 to 4.0 micrograms), when the glucagon is administered I.V. and the insulin is administered s.c. When the glucagon is to be administered subcutaneously, 1 unit of insulin can be administered in the amount of 0.02 to 200 milliunits of glucagon for each unit of insulin administered or more than 40 to 200 milliunits of glucagon, e.g. 40 to 200 milliunits per hour to a 100 kg person for each unit of insulin administered. In another embodiment, for each unit of insulin, 48-150 mU, 50-120 mU, or 80-100 mU of glucagon is administered. In a preferred embodiment the glucagon is administered subcutaneously and the ratio is about 1 unit of insulin to more than 5 to about 20 ng/kg glucagon, which amount of glucagon is administered each minute during the period of effectiveness of the insulin dose. In one embodiment, 1 unit of insulin is administered, and the glucagon is administered at a rate of 8-12 ng/kg/min. A standard dose can be created, for example, for treating a 100 kg person for 1 hour in association with 1 unit of insulin. As will be appreciated by one of skill in the art, this dose can be for basal insulin rates. When postprandial levels of insulin are desired, the amount of glucagon in the dose will be increased accordingly. In some embodiments, the glucagon is administered subcutaneously in an amount between more than 5 ng/kg/min. and less than about 20 ng/kg/min. More preferably, the amount is between about 8 and 16 ng of glucagon/kg/min for subcutaneous administration. Of course, one of skill in the art will appreciate that other dose equivalent amounts (i.e., the same effective amount administered through an alternative method) can also be determined in light of the teachings herein. As will be appreciated by one of skill in the art, and as shown in more detail below, this amount can be adjusted to correspond to the amount of glucagon required to prevent hypoglycemia, without inducing hyperglycemia. Thus, in some embodiments, the amount of glucagon administered, even through s.c. administration, is less than the 5-20 ng/kg/min values described as effective in the prevention of insulin-induced hypoglycemia. As will be appreciated by one of skill in the art, while the present disclosure focuses on Type 1 diabetes, similar methods and compositions can be used for Type 2 diabetes. In general, the amount of glucagon can be increased several fold over what is disclosed herein for Type 1 diabetes. For example, Type 2 diabetes can require 1.5 to 5 fold more glucagon, and preferably involves two to three fold more glucagon than Type 1 diabetes.

Any of the currently available forms of insulin, including but not limited to recombinant human soluble (regular) insulin, human insulin analogs, animal insulins, derived, for example, from beef, pork and other species, as well as delayed release forms, including intermediate and long acting insulin may be used for the herein disclosed compositions and methods. Moreover, any of the currently used routes of administration, as well as newer routes in development, can be employed, including but not limited to subcutaneous, intramuscular, and intravenous injection, as well as oral, buccal, nasal, transdermal, sublingual, and pulmonary airway administration. Typical doses and dose ranges for the administration of insulin to control diabetes known in the art are suitable for use in the methods and compositions of some of the embodiments.

For example, prandial short-acting insulins, such as regular insulin and the LISPRO, ASPART, and GLULISINE derivatives thereof, are well known in the art and commonly used to treat diabetes. Such insulins can be used to illustrate the embodiments in a manner applicable to other forms, including but not limited to NPH, LENTE, SEMI-LENTE, DETEMIR, ULTRA-LENTE, and GLARGINE (LANTUS), and pre-mixed formulations of regular and long-acting insulins. In this illustration, the molecular weights ascribed to all three of these prandial short-acting insulins are similar, with LISPRO at 5808, ASPART at 5825.8, GLULISINE at 5823 and regular insulin at 5807. The molecular weight ascribed to glucagon is 3483.

The usual range of prandial insulin injections in Type 1 diabetes can be approximated as two standard deviations from the mean, resulting in an insulin dose range of 2-20 units. More than 95% of Type 1 diabetics will be administered a prandial insulin dose within this range. The three prandial insulins noted above all achieve peak serum concentrations within 1-2 hours after subcutaneous administration and have a duration of effectiveness of about 5 hours.

Currently, hypoglycemia is treated by a single parenteral injection of glucagon in a dose of about 1 mg (1 unit); it has been determined that this dose is a gross excess of the dose actually required to control hypoglycemia. When glucagon is given subcutaneously or intramuscularly, serum glucagon peaks within an hour, and its effects can persist for several hours. However, it appears that currently marketed forms of glucagon are not stable in liquid form, either isolated or in vivo for prolonged periods of time, and in one embodiment, the present invention provides new pharmaceutical formulations of glucagon that are more stable, and new methods for using the stabler forms of glucagon that are currently available but not in widespread use.

It has been discovered, based in part on the respective times to peak serum level and durations of action of the prandial insulins and subcutaneously administered glucagon, that there is a mismatch between subcutaneous insulin and glucagon pharmacokinetics. One embodiment of the present invention provides longer-acting glucagon formulations and derivatives that can be used to correct this mis-match, where desired or of benefit to the patient. "Longer-acting" glucagon, as used herein, refers to a glucagon that has a half-life greater than that of standard glucagon, including both natural extract and rDNA produced synthetic glucagon.

To provide the dose of glucagon required to achieve a duration of effect that is similar to that of the prandial insulins, one can use a dose that approximates the basal replacement dose. The usual basal glucagon replacement dose by IV infusion is 0.5-0.75 ng/kg/min; one can assume that a wider range of glucagon infusions, from as low as 0.10 to 5.00 ng/kg/min (more often, 0.10 to 3.00 ng/kg/min) can be effective, depending on the patient, the insulin dose, the method of administration (e.g. I.V. vs. s.c.), and other factors. For example, in s.c. administration, the present inventors have discovered that the amount of glucagon administered can be higher, as the bioavailability of glucagon administered by subcutaneous infusion can be as low as 10%, and as low as about 35% for bolus subcutaneous administration. Thus, the dose will be increased or decreased accordingly to obtain the equivalent therapeutic effect of administering glucagon at a rate of 5 to 20 ng/kg/min. To match the PK of the insulins, these glucagon infusion rates would be continued for a period of time ranging from 150 minutes to 300 minutes. In some embodiments, the period of time of infusion can last longer than 6 hours, for example 6-7, 7-10, 10-15, 15-20, 20-24 hours, or longer. One can then multiply the replacement rates by the minimum and maximum times to give the total dose/kg. If one assumes that the typical Type 1 diabetic has a weight within the range of 50 to 100 kg, and that the high and low range dose of subcutaneous prandial insulin injection is between 2 and 20 units, then the insulin/glucagon ratios can be calculated as shown in Table 1 (see Original Patent) (showing the ratios for s.c. administration). Of course, this dosage replacement can happen through IV infusion of a dose equivalent amount. In one embodiment, the same calculations described above are used to determine the amount of delayed or extended release forms of glucagon to administer to a patient, taking into account that there will be a lower level of glucagon available initially and a higher amount of glucagon available later. While the amount of glucagon released at any point in time may not be precisely known, enough glucagon is released per unit of time from the administered formulation so that, on average, about 0.1 to 5.0 ng/kg/min. is released into the patient for embodiments in which the glucagon is administered through an I.V. In one embodiment, 0.5, 2, 3, or 4 times as much glucagon may be released on any given unit of time, depending on the patient, the type of diabetes being treated, and the mode of administration.

In some embodiments, and as illustrated in table 1 (see Original Patent), the glucagon is administered subcutaneously and is administered in an amount between 0.1 to about 30 ng/kg/min., about 4.0 to about 20 ng/kg/min., about more than 5.0 to about 30 ng/kg/min, about 6 to 25 ng/kg/min, about 6 to 20 ng/kg/min, or about 8.0 to about 12.0 ng/kg/min.

In Table 1 (see Original Patent), the amount of glucagon administered ranges from 5.6 to 675% of the amount (in weight) of insulin administered; for many patients, however, the glucagon is administered at, or is present in a composition at <225% of the weight of insulin. As will be appreciated by one of skill in the art, the amount of glucagon administered can vary depending upon many factors. Thus, ranges of the percent of glucagon to insulin can vary between 5.6 to 675%, e.g. more than 188% to less than 675%. In one embodiment, the amount of glucagon administered is expressed as a ratio to the amount of insulin administered; for example, the ratio of glucagon administered can be from 5.6 to 11.3 percent of the amount of insulin administered. In some embodiments, the amount of glucagon administered is 112 to 225% of the amount of insulin administered. As shown in Example 7 below, these amounts of glucagon can induce elevated blood glucose levels that approach hyperglycemia, as such, it is likely that lower dose ranges can be sufficient to prevent hypoglycemia, without risking hyperglycemia. Lower ranges or doses can be from 0.09% to 188% of the weight of insulin, for example. As will be appreciated by one of skill in the art, the weight of the patient can vary, from infants, e.g. 2 kg to full adults, e.g. 150 kg to 200 kg, or more.

In other embodiments, the amount of glucagon administered can be described as an amount of glucagon by weight or activity independent of the amount of insulin administered; for example, in one embodiment, the amount of glucagon administered is 200-300 or 360-900 micrograms over a nine hour period. In one embodiment, the amount of glucagon administered is between about 22 to 33 micrograms in one hour. In one embodiment, the glucagon administered ranges from more than 5 ng/kg/min to about 30 ng/kg/min s.c. In some embodiments, the amount is about 0.1 ng/kg/min to about 30 ng/kg/min. In one embodiment, the amount is about 8 to about 16 ng/kg/min, or about 12 ng/kg/min. s.c. In some embodiments, substantially lower values can be sufficient as well, depending upon the circumstances and mode of administration.

In one embodiment, hypoglycemia is a blood glucose level of less than about 50-60, and generally less than about 70 mg/dL, and hyperglycemia is a blood glucose level more than about 140 to 200 mg/dL. In one embodiment, excessive hyperglycemia is defined as a blood glucose level above 350 mg/dL. The ratio of glucagon to insulin and amounts of each is set, in accordance with the methods of the invention, to keep the blood sugar level effectively between the hypoglycemic level and the hyperglycemia level. In another embodiment, the blood sugar level is maintained between the hypoglycemic level and the excessive hyperglycemia level. In another embodiment, the blood sugar level is maintained between the hyperglycemia level and the excessive hyperglycemia level. As will be appreciated by one of skill in the art, the level need not be observed precisely, and minor dips below or peaks above these ranges are permissible. In one embodiment, the dose to be administered to a patient is therapeutically equivalent to a dose of 0.5 to 0.75 ng/kg/min of glucagon administered I.V. or is therapeutically equivalent to a dose of above 5 to about 20 ng/kg/min. s.c., i.e., 8-16 ng/kg/min of glucagon via s.c. administration. In some embodiments, 0.1 to 5 ng/kg/min. is all that is needed for the subcutaneous administration, for the prevention of the onset of hypoglycemia. In some embodiments, the same amount of glucagon (or effective ratio of glucagon to insulin) is used, even if an agent other than insulin is used to lower or control blood sugar levels. Thus, in some embodiments, the method of the invention may be practiced with an agent other than insulin, as the co-administration of glucagon, in light of the present disclosure, with a hypoglycemic agent is contemplated. Similarly, in some embodiments, a hyperglycemic agent other than glucagon is used to prevent the onset of hypoglycemia in insulin treated diabetics. In some embodiments, neither insulin nor glucagon is used, and a diabetic patient is simultaneously administered both a hyperglycemic agent (an agent that causes blood sugar levels to rise) and a hypoglycemic agent (an agent that causes blood sugar levels to decline).

As will be appreciated by one of skill in the art in view of the instant disclosure, the amount of glucagon or insulin administered to a patient can vary depending upon the mode of administration For example, the amount of glucagon (or ratio of insulin to glucagon) to be added can be described in terms of the amount to be administered via an I.V. (as in PCT Pub. No: WO 2004/060387, incorporated herein by reference). This amount can differ greatly depending upon how the glucagon is to be administered, e.g. subcutaneously or via inhalation. For simplicity, the amount of glucagon required to achieve an equivalent result can be described as a "dose equivalent." For example, a "10 ng/kg/min. s.c. dose equivalent" is the amount required to achieve the same result as would be achieved by administering 10 ng/kg/min. to a patient subcutaneously. A "s.c. dose equivalent for I.V. administration" is the amount of glucagon administered intravenously that is required to obtain the same amount of glucose or glucagon in the blood achieved by subcutaneous administration of the amount of glucagon. Thus, in the latter phraseology, the first method of administration describes what the dose administered is going to be an equivalent to using another mode of administration, and the second mode of administration recited is the mode of administration actually employed. An I.V. dose equivalent of glucagon administered subcutaneously will typically be more than the amount recited for I.V. administration, as can be seen by comparing the table above to Table 1 in PCT Pub. No. WO 2004/060387. For example, a unit to be delivered I.V. is in some patients 0.1 ng/kg/min., while the amount for the same effect to be delivered subcutaneously can be 8 ng/kg/min. in those patients. In addition, in a clinical trial described in the Examples below, the amounts of glucagon required to be administered to induce hyperglycemia in an insulin-treated diabetic were for some patients in the 8-16 ng/kg/min. range (although lower doses were seen to be effective as well), so the amounts of glucagon required merely to prevent hypoglycemia will be below that range in some patients. Given the present disclosure, one of skill in the art will be able to determine the appropriate amount in each circumstance.

As will be appreciated by one of skill in the art, the "amount of glucagon administered" is not necessarily the amount of glucagon that actually enters the bloodstream of a patient. Rather, for example, administering 9 ng/kg/min. s.c. of glucagon to a patient means that an initial solution of an initial known amount was created, and based on that amount, 9 ng/kg/min. of glucagon is administered to a patient. If there is a loss or degradation of the glucagon prior to administration, then less glucagon enters the patient, and if there is a loss or degradation of glucagon as it progresses to the patient's bloodstream and tissues, the effective therapeutic dose is lower still. As will be appreciated by one of skill in the art, the actual amount of glucagon that is active and enters the patient's circulation will in such instances be less than, in this example, 9 ng/kg/min.

One of skill in the art, given the present disclosure, can determine the dose equivalent for various methods or modes of administration. This dose equivalent can also vary depending on inter- and intrapatient variability and the bioavailability of the drug. For example, if one assumes glucagon administered through an I.V. is 100% bioavailable, then certain glucagon formulations administered through a s.c. bolus can have about 35% bioavailability, while the same glucagon formulation administered by continuous subcutaneous infusion can have a bioavailability of 10%, as shown with patient data in the Examples below. Additionally, differences between the method of administration of insulin and of glucagon can also be taken into account and determined through the methods and examples provided herein. One way this can be determined is through various assays of insulin, glucose and glucagon in a patient following various routes of administration of the glucagon, e.g., as illustrated in Example 7 (see Original Patent).

The pharmaceutical compositions for use in many embodiments of the invention can comprise those compositions useful in conventional methods for the control of diabetes and treatment of hypoglycemia. Such conventional methods, as that phrase is used herein, include those approved by the FDA, those in development, and those described in Diagnosis and Management of Type II Diabetes, by S. V. Edelman and R. R. Henry (5.sup.th Ed. PCI Publishers), the entire text of which is incorporated herein by reference, and Chapters 7 and 8 of which are especially pertinent. As used herein, a pharmaceutical formulation or pharmaceutical composition may contain a pharmaceutically acceptable excipient, diluent or carrier. The phrase "pharmaceutically acceptable" means that the carrier, diluent or excipient is compatible with the other ingredients of the formulation and administration equipment and not deleterious to the recipient thereof. Pharmaceutically acceptable excipients are well known in the art. See, e.g., Remington: The Science and Practice of Pharmacy (19th edition, 1995, Gennavo, ed.).

In one embodiment, the glucagon or similar substance is administered in a buffer. Appropriate buffers are those that maintain the mixture at a pH range from about 6.0 to about 9.0, but which do not interfere with the function of glucagon. Examples of buffers include, but are not limited to, Goode's buffers, HEPES, Tris, ammonium acetate, sodium acetate, Bis-Tris, phosphate, citrate, arginine, histidine, and Tris acetate. The selection of one or more appropriate buffers is within the skill of one of ordinary skill in the art.

The control of diabetes by insulin therapy, as well as the control of hypoglycemia by glucagon therapy, can involve parenteral administration of the insulin or glucagon. Parenteral administration may be performed by subcutaneous or intramuscular injection by means of a syringe, optionally a pen-like syringe. Some of the embodiments of the methods can be practiced using such methodology, although, as noted above, it may be preferable in some instances to provide glucagon in a manner that ensures that its duration of action more closely matches that of the insulin employed such that the glucagon is present when the risk of hypoglycemia is greatest--typically a relatively long time after eating but still within the period in which the insulin administered continues to exert its effect.

Where subcutaneous administration of insulin and glucagon are desired, a variety of methods may be employed to achieve the benefits of diabetes control and prevention of hypoglycemia. In one such method, a glucagon with a shorter duration of action than the insulin is administered within about one to four hours after the insulin is administered. This method provides benefit in that most hypoglycemic episodes begin several hours after the patient has last eaten, and many patients administer insulin shortly before a meal. Thus, by delivering the glucagon a few hours after the insulin, but prior to the onset of hypoglycemic symptoms, one can achieve the benefits of the methods of the invention. Certain embodiments provide methods for controlling diabetes with reduced risk of inducing hypoglycemia by administering insulin in continuation with a long acting glucagon and formulations thereof. Thus, in one embodiment, compositions having a long acting form of glucagon are provided.

In general, long acting forms are also known as extended release, prolonged release or controlled release (or similar term) forms. In one embodiment, delayed or slow acting glucagon is a particular form of an extended or long release form of glucagon. Delayed acting glucagon is within the general class of long acting glucagon, as delayed or slow acting glucagon will allow for glucagon activity to occur after a period of time following the administration of glucagon; however, delayed acting glucagon is effective in lower amounts at the initial administration and increases in effectiveness over time. The glucagon itself may be long acting in nature, or it may be combined with other components that allow its release over an extended amount of time.

In another embodiment, the insulin and glucagon can be administered simultaneously, with the insulin and optionally the glucagon delivered parenterally, typically by subcutaneous injection. In this method, a glucagon with a longer duration of action is preferably employed, or the glucagon is administered by a route that provides a longer duration of action, e.g., as by continuous infusion, as illustrated in the Examples below.

Such glucagon includes, but is not limited to, the glucagon, glucagon formulations, and routes of administration described in U.S. patent application publication No. 2002114829 and U.S. Pat. Nos. 6,197,333 and 6,348,214, which describe liposome formulations of glucagon that provide for reduced dosage effect and are long acting; PCT patent publication No. WO0243566, which describes the delivery of glucagon via trans-dermal patch; U.S. Pat. No. 5,445,832, which describes a long-acting glucagon formulation in polymeric microspheres; PCT patent publication No. WO0222154, which describes a slow-release glucagon that can have a duration of action measured in weeks; and U.S. Pat. No. 3,897,551 and Great Britain U.S. Pat. No. 1,363,954, which describes the prolongation of glucagon duration by iodination (each of these publications are incorporated herein by reference in their entireties.) In an embodiment, the glucagon is administered as a slow-release or depot formulation (e.g., comprising polyethylene glycol).

There are many techniques known to those skilled in the art for modifying the release and/or pharmacokinetic characteristics of proteins, include the modification of the amino acid sequence at the site corresponding to the metabolic deactivation point associated with the protein. These techniques and compositions include, "pegylation" or PEG-modification of the protein (see, for example, PCT Patent publication Nos. WO0232957, WO9831383, and WO9724440, EP patent publication Nos. EP0816381 and EP0442724, and U.S. Patent Publication No. 2002/0115592; U.S. Pat. No. 5,234,903; and U.S. Pat. No. 6,284,727); other polymer encapsulations (see EP patent publication No. EP0684044); lipophilic modification (see U.S. Pat. Nos. 5,359,030; 6,239,107; 5,869,602; and 2001/0016643; EP patent publication No. EP1264837; and PCT Patent publication Nos. WO9808871 and WO9943708; formulating into liposomes (see U.S. Pat. Nos. 6,348,214 and 6,197,333); serum albumin modification (discussed in more detail below and in PCT Patent publication Nos. WO02066511 and WO0246227 and U.S. Pat. No. 4,492,684); formulating in the form of emulsions, microspheres, microemulsions, nanoencapsulation and microbeads (see U.S. Pat. Nos. 4,492,684; 5,445,832; 6,191,105; 6,217,893; 5,643,604; 5,643,607; and 5,637,568); formulations involving ligands (see PCT Patent publication No. WO0222154); and iodination (see U.S. Pat. No. 3,897,551).

In one embodiment, an iodination method of increasing half life (as described in U.S. Pat. No. 3,897,551; see form I3G) is employed. Iodinated glucagon has extended activity (measured in terms of elevated glucose levels) of between 1 and 3 hours, depending on the extent of iodination. In one embodiment LISPRO insulin and I3Glucagon are admixed so that the modified glucagon is present at approximately 1.5% by weight of the insulin in the mixture (keeping the concentration of insulin per ml in the LISPRO formulation constant). Because of the longer lasting effect of the modified glucagon, a smaller proportion of glucagon to insulin by weight will be required to prevent hypoglycemia in some patients.

Another form of a long acting glucagon is a zinc-protamine-glucagon formulation. Examples of such Zinc protamine-glucagon formulations are known in the art (See, for example, Kaindl et al., Verh Dtsch Ges Inn Med. 1972; 78:1099-101; Kaindl and Kuhn, Z Gesamte Inn Med. 1972 Dec. 15; 27(24):1097-8; Christiansen and Tonnensen, Med. Scand. 1974 December; 196(6):495-6; Gamba et al., Minerva Med. 1977 Nov. 3; 68(53):3613-26; Kollee et al., Arch Dis Child. 1978 May; 53(5):422-4; Kalima and Lempinen, Ann Chir Gynaecol. 1980; 69(6):293-5; Aynsley-Green et al., Arch Dis Child. 1981 July; 56(7):496-508; Schmid and Wietholter, Dtsch Med. Wochenschr. 1982 Nov. 26; 107(47):1809-11; Day and Mastaglia, Aust N Z J Med. 1985 December; 15(6):748-50; Cederblad et al., Horm Res. 1998; 50(2):94-8; all herein incorporated in their entireties by reference.

Additionally, Pichler et al. (Wien Klin Wochenschr 19:91(2):49-51 (1979)) demonstrated that a zinc protamine form of glucagon had a maximal effects up to 3 hours after the actual administration of the drug, and only displayed a decrease in activity after the fourth hour. Thus, the effective half-life of zinc protamine glucagon is in the range of hours.

In one embodiment, glucagon is combined with zinc without protamine, as described in Tarding et al., (European Journal of Pharmacology, 7:206-210 (1969), hereby incorporated in its entirety by reference). This also results in a long acting form of glucagon. In one embodiment, the mixture involves a 1 to 2 ratio of zinc to glucagon.

In one embodiment, the zinc protamine glucagon is made in a manner similar to how zinc protamine insulin is made, apart from the replacement of insulin with glucagon. In one embodiment, zinc glucagon and zinc protamine glucagon is made as described in Tarding et al. (European Journal of Pharmacology 7:206-210 (1969)). For example, zinc glucagon can be made by suspending freeze-dried zinc glucagon crystals in a zinc acetate buffer, for a final concentration of 1 mg glucagon/ml, 0.05 mg zinc/ml. Alternatively, the zinc protamine glucagon can be prepared by suspending freeze-dried zinc glucagon crystals in a zinc acetate buffer containing protamine to a final concentration of 2 mg glucagon/ml, 0.15 mg zinc/ml, and 0.5 mg protamine/ml.

Another example of an agent that can be included with glucagon in compositions useful in the present methods includes a protamine sulfate, as described in combination with GLP-1 in U.S. Pat. No. 6,703,365, (issued Mar. 4, 2004, to Galloway et al.). The GLP-1 combination therein disclosed displays an increased half-life and an increased shelf life as well. Any glucagon which displays an increased half-life can be useful in the present methods and compositions.

Another means by which the half-life of the protein may be extended is through the use of "serum binders", such as can be achieved through the conjugation of albumin to glucagon by a connector. In one embodiment, the glucagon contains a moiety which allows it to attach itself to albumin in vivo. Alternatively, the glucagon may be modified such that it is able to connect to a connector, which will then allow the glucagon molecule to be associated with a protein such as albumin in vivo. Thus, the modified glucagon can be directly added to a patient, where it will subsequently bind to albumin in the host, which will in turn result in the extension of the useful life of glucagon in the system. This approach has been described for other purposes for GLP-1 in U.S. Patent Publication 20030108568, published Jun. 12, 2003 to Bridon et al., as well as for various other proteins (See, for example, U.S. Pat. Nos. 6,277,863, issued Aug. 21, 2001 to Krantz et al., 6,500,918, issued Dec. 31, 2002, to Ezrin et al., 6,107,489, issued Aug. 22, 2000, to Krantz et al., 6,329,336, issued Dec. 11, 2001, to Bridon et al., and 6,103,233 issued Aug. 15, 2000, to Pouletty et al., all of which are incorporated by reference in their entireties). In one embodiment, the binding between glucagon and albumin occurs with the aid of biotin and avidin or streptavidin. In another embodiment, glucagon can be attached to other proteins through the use of maleimide groups and sulfur groups. The glucagon can be attached to any suitable protein, not only albumin.

In one embodiment, a prolonged release form of glucagon is a gel or fibril based form of glucagon. These may be prepared as described in Gratzer and Davies (European J. Biochem., 11:37-42 (1969), hereby incorporated in its entirety by reference.)

Other forms of prolonged release glucagon are also contemplated for use in the present methods. Long release preparations may be made using polymers to complex or absorb the glucagon. The controlled delivery may be exercised by selecting appropriate macromolecules and the concentration of macromolecules as well as the methods of incorporation to control release. For example, diffusion controlled systems may be used. Examples of such materials include particles of a polymeric material such as polyesters, polyamino acids, polyvinylpyrrolidone, methylcellulose, carboxymethylcellulose, hydrogels, poly (lactic acid), or ethylene vinylacetate copolymers. Alternatively, instead of incorporating a compound with these polymeric particles, it is possible to entrap a compound of some of the embodiments in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules, respectively, or in colloidal drug delivery systems, for example, liposomes, albumin microspheres, microemulsions, nanoparticles, and nanocapsules, or in macroemulsions. Such teachings are disclosed in Remington's Pharmaceutical Sciences (1980). In one embodiment, the rate of dissolution of the drug is primarily controlled by the dissolution of a shell, which encapsulates the drug.

In one embodiment, an osmotic pump system is used to provide a prolonged release of glucagon, allowing the rate of release of the drug to be controlled by the inflow of water across a semipermeable membrane into a reservoir that has an osmotic agent. In another embodiment, ion exchange resins are used to control the release of glucagon.

In one embodiment the extended release form of glucagon is a preproglucagon [Lund, et al., Proc. Natl. Acad. Sci. U.S.A. 79:345-349 (1982)]. This polypeptide is subsequently processed to form proglucagon, which is subsequently cleaved into glucagon and a second polypeptide (Patzelt, C., et al., Nature, 282:260-266 (1979)). Thus, by administering this form of prepro- or proglucagon, one is able to delay the onset of the activity of the glucagon.

In one embodiment, glucagon is administered in a form that allows substantially no release of active glucagon initially, and then allows for a small amount of release of glucagon over time. Such a form of glucagon is useful when prolonged periods between drug intake will occur and the desired result is an effect towards the end of the prolonged period, for example, during nocturnal periods. The form may be inherent in the glucagon protein itself, i.e., a semi-synthetic glucagon variant, due to compositions associated with the protein, due to the formulations in which the glucagon is administered, due to the route and method by which the glucagon is administered, as well as other reasons as described herein.

Glucagon with a low activity level is desirable in some circumstances. As the delivery of precise amounts of small volumes can be difficult, especially over prolonged periods of time, compositions of glucagon comprising components that lower the activity of glucagon may be desirable in some situations to allow the administration of larger volumes of sample. Alternatively, variants or mutants of glucagon with a lower activity level can be used to achieve this result. The term "glucagon" can encompass both wild-type glucagon and variants or derivatives of glucagon.

In some embodiments, a combination of an insulin component and a slow release form of a glucagon provided by the invention is employed in the methods of the invention. As will be appreciated by one of skill in the art, the combination may be achieved through a single or multiple formulations and single or multiple means of administering the insulin component or the glucagon component.

In one embodiment, parenteral administration is performed by means of an infusion pump. A variety of insulin pumps are available and in common use that are suitable for delivery of the insulin and glucagon compositions (as well as suitable for the delivery of insulin, with glucagon being delivered by another route, such as transdermal). Such pumps include, for example and without limitation, the pumps marketed by Medtronic (such as the MiniMed), Animas Corporation, Disetronic, and Dana. The glucagon can optionally be administered with the insulin, and a glucagon with a short duration of action can be employed, as the glucagon can be administered as necessary. In one embodiment, the glucagon can be administered intravenously at a rate of 0.5-0.75 ng/kg/min or within the wider range of about 0.10-5 ng/kg/min, alternatively, within the range about 0.10-3 ng/kg/min. or in an amount that is an intravenous dose equivalent. In a preferred embodiment, the glucagon is administered subcutaneously and is administered in an amount between about 4 and 30 ng/kg/min, about more than 5.0 up to 25 ng/kg/min, about 8.0 to 20 ng/kg/min, or about 8.0 to 12.0 ng/kg/min. Lower amounts of glucagon can be administered (0.1-5 or 2-5 ng/kg/min.) subcutaneously to prevent hypoglycemia in some patients. In one embodiment a dose will prevent hypoglycemia without causing excessive hyperglycemia. Hyperglycemia is a blood glucose above the normal range. Glucagon can elevate blood glucose above where it would be without the administration of exogenous glucagon, and in a preferred embodiment, the dose administered is one that is still protective against hypoglycemia but only minimally elevates blood glucose above the levels maintained in the patient when not suffering from hypoglycemia.

Thus, in one embodiment, the present invention provides a new drug delivery device, a pump suitable for the delivery of insulin for the control of diabetes, and for the delivery of glucagon for the control of hypoglycemia in a human, i.e., the pump contains both insulin and glucagon. The pump may include a reservoir containing both insulin and glucagon. In other embodiments, the pump includes insulin and glucagon in two separately controlled reservoirs. A method of controlling diabetes in a human patient to reduce the risk of hypoglycemia is provided, said method comprising administering both insulin and glucagon to the diabetic patient using a pump of one of the embodiments described above.

In another method, either the insulin or the glucagon or both is provided in a formulation that is a powder or a liquid suitable for administration as a nasal or pulmonary spray or for ocular administration. A variety of such formulations are known for insulin and glucagon, and the present disclosure provides methods for using these known formulations for administering either one independently, as well as for administering the corresponding formulations of the embodiments that comprise both insulin and glucagon to control diabetes with a reduced risk of inducing hypoglycemia.

Methods and formulations for nasal, pulmonary, or ocular administration include those in PCT patent publication Nos. WO0182874 and WO0182981, which describe aerosolized insulin and glucagon; European patent publication EP1224929 and U.S. Pat. No. 6,004,574, which describe an inhaled glucagon with melezitose diluent; U.S. Pat. No. 5,942,242, which describes formulations of insulin and formulations of glucagon suitable for nasal administration; U.S. Pat. No. 5,661,130, which describes formulations suitable for ocular, nasal and nasolacrimal or inhalation routes of administration; U.S. Pat. No. 5,693,608, which describes methods and formulations for the nasal administration of insulin and for glucagon; U.S. Pat. No. 5,428,006, which describes methods and formulations for the nasal and other mucosal administration of insulin and for glucagon; U.S. Pat. No. 5,397,771, which describes methods and formulations for the mucosal administration of insulin and of glucagon; U.S. Pat. No. 5,283,236, which describes methods and formulations for the ocular administration of insulin and of glucagon; and European patent publication EP0272097, which describes a formulation of glucagon for nasal administration. In addition to these formulations, the methods of delivering these formulations as described are also contemplated.

In one embodiment, compositions and methods are provided for controlling diabetes with a reduced risk of inducing hypoglycemia by administering insulin and glucagon, in which one or both of the insulin and glucagon is administered transdermally, e.g. from a patch, optionally a iontophoretic patch, or transmucosally, e.g. bucally. Manufacture and use of transdermal delivery devices are well known in the art (see, e.g., U.S. Pat. Nos. 4,943,435 and 4,839,174; and patent publication no. US 2001033858). The transdermal delivery of glucagon, and a patent publication describing transdermal formulations of glucagon, has been cited above, and U.S. Pat. No. 5,707,641 describes methods and formulations for the transdermal delivery of insulin.

Moreover, some embodiments of the methods can be practiced by oral administration of both insulin and/or glucagon in the therapeutically effective amounts and their dose equivalents described herein. Methods and formulations for the oral administration of insulin and of glucagon include those described in PCT patent publication No. WO9703688.

The insulin and/or glucagon employed in the methods and formulations can be supplemented with or replaced by compounds and compositions that have similar activities or effects. For example, glucagon may be replaced with glucagon mimetics or variants of glucagon.

Insulin can be replaced or supplemented with hypoglycemic agents, including but not limited to Insulin Sensitizers, DPP IV inhibitors, and GLP1 analogs, insulin secretagogues including, but not limited to, sulfonylureas such as Acetohexamide (DYMELOR), Chlorpropamide (DIABINESE), Tolazamide (TOLINASE), Tolbutamide (ORINASE), Glimepiride (AMARYL), Glipizide (GLUCOTROL), Glipizide Extended Release (GLUCOTROL XL), Glyburide (DIABETA, MICRONASE), Glyburide Micronized (GLYNASE, PRESTAB); Meglitinides such as Nateglinide (STARLIX) and Repaglinide (PRANDIN); Gastric Inhibitory Polypeptide (GIP); Glucagon-like peptide (GLP)-1; Morphilinoguanide BTS 67582; Phosphodiesterase inhibitors; and succinate ester derivatives; insulin receptor activators; insulin sensitizing Biguanides such as Metformin (GLUCOPHAGE), Thiazolidinediones (TZD) such as Troglitazone (REZULIN), Pioglitazone (ACTOS), and Roziglitazone (AVANDIA); Non-TZD peroxisome proliferator activated receptor .gamma. (PPAR.gamma.) agonist GL262570; Alpha-glucosidase inhibitors such as Acarbose (PRECOSE) and Miglitol (GLYSET); Combination agents such as Glucovance (GLUCOPHAGE with GLYBURIDE); Tyrosine Phosphatase Inhibitors such as Vanadium, PTP-1B inhibitors, and AMPK activators, including 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR); and other agents such as Exendin (EXENATIDE (synthetic exendin-4)) and Amylin (SYMLIN.RTM. (pramlintide acetate)), D-Chiro-Inositol, altered peptide ligands (NBI-6024), Anergix DB complex, GABA inhibit melanocortin, Glucose lowering agent (ALT-4037), Aerodose (Aerogen), insulin mimics, Insulin-like growth factor-1 alone or in a complex with BP3 (SOMATOKLINE), metoclopramide HCL (Emitasol/SPD 425), motillde/Erythromycin analogs, and GAG mimetics.

In one embodiment, variants of glucagon are contemplated. Such variants may comprise a single or many amino acid changes, for example, from one to all of the amino acids may be changed, relative to the native human glucagon sequence, so long as the resulting variant functions as required herein. In one embodiment, the HELIX content is adjusted at the C-terminus, as well as partial agonists are combined to provide more of a "basal" input. In one embodiment, transient PEG-modifications at the N-terminus, to control activation can be complemented with mutations introduced at the C-terminus, for controlling affinity. Examples of such variant glucagon molecules, and their resulting characteristics and activities, are available in the art. For example, Sturm et al., (J. Med. Chem. 41:2693-2700 (1998)) teaches a general structural function relationship for some of the salt bridges in glucagon. In one embodiment, the variant glucagon has a Lys substitution at positions 17 and 18, and a Glu substitution at position 21, resulting in a variant with a 500 percent binding affinity and a 700 percent relative potency. In one embodiment, the variant glucagon amide has only a Lys substitution at position 17, resulting in a variant with a 220 percent binding affinity and a 230 percent potency. In another embodiment, the variant glucagon amide has a Nle substitution at position 17, a Lys substitution at position 18, and a Glu substitution at position 21, resulting in a variant with 150 percent binding affinity and a 300 percent potency. In another embodiment, the variant glucagon molecules display low binding ability or low activity. Thus, for example, a glucagon amide variant with a lysine at position 18 may be used, as it only has 36 percent of the normal binding affinity and only 12 percent of the normal potency. Another example would be a glucagon variant with a Phe at position 18, which has only 4.7 percent of the normal binding affinity and 0.9 percent of the relative potency.

In one embodiment the only pharmaceutically active components of the formulation are insulin and glucagon. In one embodiment, the pharmaceutical composition (e.g., containing both insulin and glucagon) is not formulated as an aerosol and/or does not contain troglitazone hydrochloride (and may not contain any thiazolidinedione). In an embodiment, the formulation is not administered orally and/or is not administered nasally. In one embodiment, the pharmaceutically active components of the formulation are administered transdermally, but not through a patch. For example, the active components can be administered through the use of a cream.

As discussed above, the simultaneous effective administration of low doses of glucagon together with insulin can help prevent insulin-induced hypoglycemic events. The prevention of these events will have various beneficial results.

Repeated mild to moderate hypoglycemic events can result in a loss of hypoglycemic awareness by the subject. Thus, the subject may no longer be able to detect that he or she is actually experiencing a hypoglycemic event, increasing the risk that more hypoglycemic events can occur. Thus, the above compositions and methods can be optimized so as to reduce the risk of this occurring. The above ratios of insulin and glucagon and amounts of glucagon recited for the prevention of hypoglycemia can be sufficient to treat this condition, and the methods of the invention include methods for adjusting the amount administered to achieve the desired therapeutic effect for a particular patient, mode of delivery, or formulation. In some embodiments, the combination of glucagon and insulin is administered to a patient to prevent the loss of hypoglycemic awareness by the subject. In other embodiments, the glucagon and insulin are administered so as to restore hypoglycemic awareness to the subject. This can be achieved by administering an amount of glucagon so that additional episodes of hypoglycemia are reduced or prevented. The amount can vary, e.g. 8-16 ng/kg/min. administered subcutaneously or 0.1-5 ng/kg/min intravenously.

As will be appreciated by one of skill in the art, these therapies and compositions can be useful not only for people with diabetes but with anyone taking insulin or other hypoglycemia inducing agent.

As will be appreciated by one of skill in the art, not every episode of mild or moderate hypoglycemia needs to be prevented. The amount or percent of events inhibited can vary by the particular situation and subject and can include inhibiting 2-5, 5-10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-99, or 99 percent to all of the mild/moderate hypoglycemic events. Additionally, hypoglycemia need not be prevented in every case and can be delayed in some embodiments. Any amount of delay can be useful, for example, a delay of 1-10, 10-30, 30-60, 60-120, 120-300, 300-600 or more minutes. Alternatively, a delay of an additional 1-20, 20-60, 60-100, 100-200, or 200% to 10 fold Additionally, not all of a patient's sensitivity to hypoglycemia needs to be restored or preserved, e.g. 1-10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-99, 99-100% can be restored or prevented from loss. "Hypoglycemic sensitivity" or "hypoglycemia unawareness" can be based on the individual's ability to detect the occurrence of a hypoglycemic event. For example, hypoglycemia unawareness can be an inability to detect 1-20, 20-40, 40-50, 50-70, or more percent of the hypoglycemic events (e.g., glucose levels fall below 50 mg/dL in the blood). Alternatively, the inability to detect a particular symptom of hypoglycemia can also be used to determine hypoglycemia unawareness and how successfully it is being treated. Signs and symptoms include, for example, shakiness, dizziness, sweating, hunger, headache, irritability, pale skin color, sudden moodiness or behaviour changes, clumsy or jerky movements, difficulty paying attention, confusion, and a tingling sensation around the mouth. A description of various possible categories of hypoglycemia can be found in "Defining and Reporting Hypoglycemia in Diabetes" Diabetes Care, 28:1245-1249 (2005), hereby incorporated by reference in its entirety. In particular, symptomatic, asymptomatic, and probably symptomatic hypoglycemia involve plasma glucose levels below or equal to 70 mg/dl. As noted herein, in some situations, lower levels of blood glucose can also be used as a threshold.

Kits

In some embodiments, the compositions described herein are provided in kit form. In one embodiment, the kit comprises a vial of glucagon, a vial of insulin, a means for administration, such as a syringe or pump, and instructions for the administration of the glucagon and insulin. In some embodiments, the glucagon and insulin are premixed in a single vial. In other embodiments, the insulin and glucagon are premixed in a syringe. The particular instructions will vary depending upon the desired use of the kit, e.g. for nocturnal control of hypoglycemia or otherwise. The instructions can be determined by one of skill in the art, given the present disclosure and the particular use intended for the kit. In one embodiment, the instructions will describe the methods disclosed herein.

Exemplary kits contain glucagon and one or more of the following packaged together: (1) insulin; (2) a solution (e.g., excipient) for resuspending or diluting glucagon (3) a device for administering glucagon and/or insulin; and (4) instructions. In one embodiment, the device (3) contains the glucagon and/or contains insulin.

A kit may comprise glucagon in a powder form within a sterile vial with a standard septum seal. In one embodiment, the vial contains a mixture of 1 mg of lyophilized glucagon, 49 mg lactose, and hydrochloric acid to adjust the pH (glucagon is soluble below pH 3 or above pH 9.5). The kit also has a pre-filled glycerine syringe, which contains 12 mg/ml of glycerine in a mixture of water, and hydrochloric acid. A second container holds a 1 mg/mL solution of insulin, which may be stored in liquid form in a syringe. The kit further has instructions, instructing the user to inject 1 mL of diluent from the pre-filled glycerine syringe into the vial. The instructions then direct the user to collect an amount of the glucagon/glycerine solution into the syringe containing the insulin. This amount will vary depending upon intended use and the particular user and may be determined by a physician.

In one embodiment, the volume of glucagon collected in the syringe is between 0-5% of the volume of insulin to be injected. The kit may comprise tables and/or charts allowing for ease of use and customization to determine what amount or ratios should be used for each user and situation.

The entire dose in the insulin syringe can then be injected (children are typically administered 50% of a standard dose, and the kit can be modified accordingly). In one embodiment, the insulin syringe and the glycerine syringe are one and the same, in which case the starting amount of glucagon is lower to maintain the appropriate ratio of glucagon to insulin that is injected. In another embodiment, the insulin, glucagon and glycerine are premixed in the kit. Instructions are adjusted accordingly for the particular embodiment used. In one embodiment, the kit comprises a glucagon kit, an insulin kit, and instructions for how to combine the two kits. As will be appreciated by one of skill in the art, any of the above discussed compositions or methods may be included in the kit as components or instructions. Thus, for example, various methods of administration, various compositions of insulin or glucagon, and various buffers or solvents may be used in the kits. In one embodiment, a means of administering insulin rapidly is combined with a means of administering glucagon more slowly. In one embodiment, the kit comprises only a form of glucagon with a set of instructions.

In one embodiment, the instructions can direct the user to administer more than 5 to 20, e.g. 6 to 16, ng/kg/min. of glucagon subcutaneously. In one embodiment, the instructions will direct the user to administer 30-45 ng/kg/hour of glucagon. In one embodiment, the units of glucagon are in 1500 ng and 2250 ng size doses for a 50 kg person, one dose to be taken each hour. In another embodiment, the units of glucagon are in 3000 to 4500 ng size doses, for a 100 kg person, one to be taken each hour. The kit can include a device for subcutaneous administration. In one embodiment, the units of glucagon are in a 36 microgram size dose for a 50 kg person, one dose to be taken each hour. In another embodiment, the units of glucagon are in 24 to 96 or 36 to 96 microgram size doses, for a 100 kg person, one to be taken each hour. These subcutaneous values can be sufficient to create hyperglycemia in some diabetic patients; thus, in some embodiments, less glucagon is required, e.g. an amount similar to that to be administered intravenously, 0.1-5 ng/kg/min. or higher. In some embodiments, the kits include instructions regarding doses for the age, weight, and sex of the individual. In one embodiment the instructions include information concerning doses to take in view of future activities, such as sleeping, eating (e.g., how much and what type of food), sitting, or exercising. As will be appreciated by one of skill in the art, an I.V. or s.c. dose equivalent can also be used if glucagon is to be administered in another manner. In some embodiments, the kits contain unit doses of glucagon to be added with the insulin. For example, a unit dose can be about 50 or 100 micrograms (or milliunits), which can be sufficient to protect a 100 kg subject for a one hour period from hypoglycemia. Unit doses can be prepared for 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 16, 18, 20, 22, 24 or more hours or days. Smaller doses for smaller people or fractional hours are also contemplated.

Unit Doses of Glucagon

In one embodiment, rather than providing a mixture of glucagon and insulin, unit doses of glucagon alone are provided so as to be readily administrable to a subject as required, to prevent insulin-induced hypoglycemia. As the ratio of glucagon to insulin can be low, the amount of glucagon in the unit dose can also be low. As will be appreciated by one of skill in the art, the actual amount of glucagon in each dose will depend upon the characteristics of the individual, possible activities that the individual is going to do or has done, how the dose is to be administered and the form of the glucagon. Thus, the doses described below are only representative of some of the possible doses. The dosage can be determined by the skilled practitioner in view of the present disclosure.

A unit dosage form of glucagon contains a discrete quantity of glucagon for administration, and may be in the format of tablets, capsules, or powders in a container such as a vial or ampoule, cartridge, syringe, inhaler, transdermal patch, or other container or package. The quantity of glucagon in a single unit dose form preparation is typically from 0.002 mg to 0.1 mg. However, as will be appreciated by one of skill in the art, the amount in each dose can vary based on the manner that the material is to be administered. The previous units are for I.V. administration. For s.c. administration, the amount of glucagon in a unit dose can be, for example, from 0.002 mg to 0.2 mg or 0.036 mg to 0.4 mg for a 100 kg person, which dose should be effective for at least 1 hour. Preferably, the unit dose is between about 40 micrograms and 300 micrograms, and more preferably, between about 50 and 100 micrograms. Of course, these numbers can be adjusted based on the size of the average person to be treated and the duration of hypoglycemia prevention desired per unit dose. For example, with slow release formulations, it can be particularly advantageous to include sufficient glucagon for release over 2-3, 3-5, 5-8, or more hours. Thus, larger doses are possible, in certain circumstances. Lower amounts, even through s.c. administration, can also be used to ensure that hyperglycemia does not even transiently occur.

A single unit dosage form contains sufficient glucagon for a single administration of glucagon as described herein. Unit dosages can be designed for particular events. For example, they can be designed for use before or after the administration of insulin. Alternatively, they can be designed for administration in view of activities such as eating or exercising or going to sleep. As the amount of glucagon to be administered will depend upon various factors of a patient, such as lifestyle and weight, the unit dose can be expressed in universal units for ease of adjusting the dose. Additionally, how the unit is to be administered can also alter the amount of glucagon one places in each unit dose. These universal unit dosages are actually unit doses that are divided into smaller individual parts. Thus, a 50 kg individual can take 5 parts of these universal unit doses, while a 100 kg individual might take 10 parts. This allows greater customization of the glucagon intake. Of course, lower amounts of glucagon, e.g. similar to I.V. administration, can also be used if lower levels of elevated blood sugar are satisfactory. Thus, even for subcutaneous administration, a unit dose can be between 0.036 mg and 0.2 mg or 0.002 mg and 0.2 mg, for example.

In a related aspect, a pharmaceutical preparation of glucagon in daily unit dosage form is provided. The daily dosage form contains sufficient glucagon for one day, including the case in which glucagon is administered multiple times during a single day as described herein. For example, there may be multiple (e.g., 2 or 3 or more) glucagon administrations after a meal or meals during the day (see, e.g., Example 1 and/or administrations for prevention of nocturnal hypoglycemia; or continuous administration via, for example, transdermal patch or pump). In one embodiment, for example, via I.V. administration, 0.02 mg to 1 mg glucagon is provided in a container accompanied by instructions (e.g., a label) that the glucagon should be administered as separate doses over the course of a day. Usually the amount of glucagon is not more than about 0.04 U. and is often not more than about 0.02 U. not more than about 0.01 U. not more than about 0.005 U and sometimes not more than about 0.002 U. In one embodiment, the amount of glucagon given over one day is about 0.84 mg via I.V. or a dose equivalent for s.c. injection. For subcutaneous administration, 960 to 4800 micrograms of glucagon can be provided for administration over a day. In one embodiment, the glucagon is in a slow release form that is given all at once. In another embodiment it is in the form of, for example, 6 pills, one to be taken every four hours.

In a related aspect, a pharmaceutical preparation of glucagon in multiple dosage form is provided. A multiple dosage form of glucagon can contain a sufficient dose for administration for one, two, three, four, five, or six days, one week, or even more than one week. In one embodiment, for example, 0.02 to 0.036 mg to 1 mg of glucagon is provided in a container accompanied by instructions (e.g., a label) that the glucagon should be administered as separate doses over the course of a day or more than one day.

In one embodiment, a daily dose or multiple dose of glucagon is prepared by resuspending a powder in a liquid excipient, and a portion of the resulting solution can be administered at each administration during the day (or several days in the case of some multiple dose forms).

In addition to glucagon, the unit dosage form, daily dosage form or multiple dosage form can include other components, such as excipients, buffers, stabilizers, carriers and the like, as well as other pharmaceutically active agents. In one embodiment, as discussed above, the unit dose includes insulin or an insulin secretagogue.

Multiple doses of glucagon (e.g., multiple daily doses) can be packaged together in a box, bubble-wrap, or in other well known formats.

In general, the dosage forms will be labeled or will be accompanied by instructions for proper dosing. For example, the daily dosage form may be labeled to indicate the number and/or weight or volume of unit doses in the container. The dosage forms may also be labeled or otherwise indicate the age of the patient for whom the preparation is intended. For example, the dosage form may be indicated as suitable for adults, children over 15 years of age, children over 10 years of age, children over 5 years of age, and the like.

In one embodiment, any of the above glucagon dosages may comprise a extended release glucagon. In such embodiments, the dosage is appropriately adjusted, as disclosed herein, to maintain a blood glucose level within the desired ranges.

Glucagon Solutions

Administration of low doses of glucagon (e.g., less than 0.01 U) can be inconvenient using formulations prepared according to conventional methods (e.g., resulting in an approximately 1 mg/ml solution). Accordingly, in some embodiments, a lower concentration glucagon solution is made and/or administered. Administration, as used in this context, includes self-administration (whether by injection, by infusion using a pump, or other methods) and administration by another. In various embodiments, glucagon is administered as a solution having a concentration of less than about 0.25 mg/ml, for example, less than about 0.2 mg/ml, less than about 0.1 mg/ml, less than about 0.05 mg/ml, less than about 0.01 mg/ml, or even less than about 0.005 mg/ml of glucagon. In an embodiment, the concentration of glucagon is preferably at least about 0.001 mg/ml. In another embodiment, the concentration of glucagon is at least about 0.01 mg/ml. Such amounts can be appropriate for I.V. administration and dose equivalent amounts can be created for other methods of administration. For example, if the method of administration is s.c. injection, then the concentration of glucagon can be higher, at least about 0.01 mg/ml, or 0.05 mg/ml, or, 0.2 mg/ml, 0.5 mg/ml, or between about 0.5 mg/ml and 2 mg/ml of glucagon. In some embodiments, these doses are combined with a device that can administer the doses in low amounts over a prolonged period of time, such as a pump.

Glucagon can be resuspended in any pharmaceutically acceptable carrier, diluent or excipient.

In one embodiment, a pharmaceutically acceptable formulation of glucagon contains a concentration of less than about 0.25 mg/ml, less than about 0.2 mg/ml, less than about 0.1 mg/ml, less than about 0.05 mg/ml, less than about 0.01 mg/ml, or even less than about 0.005 mg/ml when it is to be administered I.V., or a dose equivalent amount for other methods of administration. For example, for compositions that are to be administered subcutaneously, a pharmaceutically acceptable formulation of glucagon contains between 0.5 and 2 mg/ml of glucagon.

In a related embodiment, a method of preparing a glucagon formulation for therapeutic use is provided and involves adding an aqueous solution to a composition comprising glucagon (such as, but not limited to, a single unit dose, daily dose or multiple doses of glucagon as described above) in a quantity that results in a solution containing glucagon at a concentration of less than about 0.25 mg/ml, less than about 0.2 mg/ml, less than about 0.1 mg/ml, less than about 0.05 mg/ml, less than about 0.1 mg/ml, or even less than about 0.05 mg/ml for I.V. administration. Concentrations 2 to 10 fold higher (or more) can be used for other methods of administration, such as subcutaneous administration. The solution can contain other agents, both pharmaceutically active and/or inactive.

In one embodiment, the glucagon solution is loaded into, or is contained in, a device for delivery to a patient. In some embodiments, the device contains at least about 0.1 ml, at least about 0.2 ml, at least about 0.3 ml, at least about 0.4 ml, at least about 0.5 ml or more than 0.5 ml of a glucagon solution.

In a related aspect, the further step of administration or self-administration to a human subject with diabetes is provided. In one embodiment, the subject does not exhibit symptoms of hypoglycemia. In one embodiment the human is an adult. In one embodiment the human is older than 10 years old, and optionally older than 15 years old or older. In one embodiment, the subject is not suffering from a stomach ailment.

In one embodiment, any of the above glucagon solutions may comprise an extended release glucagon. In such embodiments, the dosage is appropriately adjusted, as disclosed herein, to maintain a blood glucose level within the desired ranges described herein.

The methods and compositions disclosed herein may be used to treat human patients as well as other mammals (e.g. rats, mice, pigs, non-human primates, and others). In some embodiments the human patient is a child or juvenile; in one embodiment the human patient is an adult. In some embodiments the patient is a Type I diabetic. In one embodiment the patient is a Type II diabetic. In one embodiment the patient is a brittle Type I or Type II diabetic. In one embodiment, the non-human mammal is an animal model for the study of diabetes, e.g. Zucker diabetic-fatty (ZDF) rats, and db/db mice.

While many of the examples and much of the description provided herein is explicitly directed to subcutaneous administration of low doses of glucagon, other aspects are also disclosed. For example, while the subcutaneous doses described herein are generally greater than 5 and less than 20 ng/kg/min., other doses are also contemplated for the various embodiments described herein. For example, doses from 0.1 to 5 ng/kg/min. for I.V. or s.c. administration, especially in combination with long acting forms of glucagon (such as zinc protamine), various kits, and unit doses are contemplated along with the more than 5 to 20 or 30 ng/kg/min. doses. Additionally, as pointed out below, doses at 4 ng/kg/min., and lower, of s.c. glucagon can also be effective in preventing or delaying hypoglycemia. Thus, in some embodiments, the dose administered subcutaneously to prevent or delay hypoglycemia is about 0.1-5, 1, 1-2, 2-3, 3-4, 4-5, more than 5, 5-6, 6-8, 8-12, 12-16, 16-20, or 20-30 ng/kg/min. Corresponding amounts for unit doses, other doses for administration, or kits are also contemplated. For example, a 1 hour unit doses of glucagon for a 100 kg person at 4 ng/kg/min. would contain 24 micrograms of glucagon, and a 1 hour pharmaceutical composition would contain 24 micrograms of glucagon and 1-3 units of insulin. As will be appreciated by one of skill in the art, any of the disclosed doses can be turned into one hour unit doses or other aspects described herein given the present disclosure. This can depend upon dose amount (e.g., 0.1 to 30 ng/kg/min. or 6 to 16 ng/kg/min.), presence and amount of insulin (e.g. 0 or 2-20 Units), the size of the patient (e.g. 3-200 kg), and the number of hours of desired effectiveness (e.g., 0.5-24 or more).
 

Claim 1 of 20 Claims

1. A system for reducing the risk of hypoglycemia, said system comprising: a syringe for administration of glucagon to a subject; and a slow release dosage of glucagon that provides 2 to 16 ng of glucagon per kilogram of subject weight per minute to a subject, for a period of at least 1 hour, wherein said glucagon is administered subcutaneously.
 

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