Abstract:
Disclosed are aqueous multivitamin/trace elements formulations stabilized by a water soluble, organic acid that contains carbon-to-carbon unsaturation and water soluble salts thereof selected from the group consisting of maleic acid, fumaric acid, maleamic acid and acrylic acid.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a method of stabilizing aqueous parenteral solutions of multivitamins in the presence of trace elements and compositions produced thereby for human and veterinary administration. 
     As is well known, in addition to the various basic nutritive materials which are required by humans and animals, a variety of other nutrients and essential elements are also required for the maintenance of good health. The present invention is directed to nutrients and essential elements, sometimes called &#34;micronutrients&#34;, from which relatively very small amounts are needed to provide a well-balanced, healthy diet. For convenience, the compositions of the invention will be described as relate to humans, however, the same can as well be used for veterinary purposes. While the compositions of the invention may be used as regular supplements to nutrients obtained through the digestive system, it especially concerns total parenteral nutrition to provide nutritional support for persons unable to meet their nutritional requirements through the digestive system, i.e. for nutritional rehabilitation of patients. 
     Total parenteral nutrition (TPN) has been used for many years and an expanded knowledge of nutritional requirements led to the development of a wide array of products from which the TPN solutions can be formulated. The Nutritional Advisory Group of the American Medical Association (AMA) has developed recommendations for the parenteral use of multivitamin preparations. The guidelines for adult formulations are as follows (JPEN 3: 258-262, 1979) 
     
         ______________________________________            DailyVitamin          Administration______________________________________A                3,300       IUD                200         IUE                10          IUAscorbic Acid    100         mgFolacin          400         mcgNiacin           40          mgRiboflavin       3.6         mgThiamin          3           mgPyridoxine (B6)  4           mgCyanocobalamin (B12)            5           mcgPantothenic Acid 15          mgBiotin           60          mcg______________________________________ 
    
     The medical profession has focused increasing attention on the importance of trace elements in the nutritional management of medical, surgical, and traumatic conditions. The AMA has also published guidelines for trace element preparations for parenteral use (JPEN 3: 263-267, 1979): 
     
         ______________________________________          DailyTrace Elements Administration______________________________________Zinc           2.5-4         mgCopper         0.5-1.5       mgChromium       10-15         mcgManganese      0.15-0.8      mg______________________________________ 
    
     The AMA did not address other trace elements, however, there are increasing data for the role of these various trace elements in good nutritional support. It is generally known that the &#34;essential elements&#34;, i.e. calcium, magnesium, sodium and potassium, furthermore zinc, manganese, copper, cobalt, chromium, iron, molybdenum, vanadium, selenium and nickel are indispensable for the normal function of living organisms. The essential elements are the constituents or activators of numerous enzyme systems, they are in close correlation with the level of certain vitamins in the organism and with the function of the hormone system. The deficiency of essential elements greatly suppresses the biosynthesis of proteins, enzymes, hormones and other biologically active substances required to control the normal functions of the living organism as a whole. 
     The JPEN 5: 424-429, 1981 reports on health disorders associated with the insufficiency of some essential trace elements in TPN: Zinc deficiency manifests in a variety of diseases including acrodermatitic skin lesions, impaired immunity, poor growth, impaired wound healing, and mental disturbances; copper deficiency results in hematologic abnormalities, usually anemia with leukopenia and neutropenia; chromium deficiency has been recognized to play a role in glucose intolerance, weight loss, peripheral neuropathy or encephalopathy; and selenium deficiency in experimental animals was observed to cause liver necrosis, pancreatic atrophy, and muscular dystrophy. Manganese is an actuator of several enzymes being involved in protein synthesis and function of the central nervous system. It is essential for bone structure and reproduction. 
     2. Description of the Prior Art 
     In general, liquid multivitamin preparations of the prior art are packaged in two separate vials or syringes, or double compartment vials or syringes to prevent interaction between some of the vitamins. Such interaction results in discoloration of the solution and loss of potency. Another approach to solve the interaction problem resulted in lyophilizing multivitamin preparations and reconstituting the same just prior to injection. 
     The ingredients interaction problem is even more serious when, in addition to containing multivitamins, the preparation also contains trace elements, especially copper. To circumvent the problem, the prior art, again, provided a two or three package system, one or two of which contained the multivitamins and one the trace elements. The contents of the packages were either separately infused into the patient or were admixed just prior to infusion. While the former method is undesirably cumbersome, the latter method is unsatisfactory for the reason that the reactions between the trace elements and the multivitamins are so rapid that the browning reaction and turbidity can be observed within minutes of admixing the two phases. In addition, the interaction could cause clogging of the infusion needle and the introduction of solid particles into the vein of the patient. This problem could be especially serious with infusions mixed several hours prior to addition to TPN solutions. 
     The present invention is designed to solve the above-described problems and to provide multivitamin/trace elements formulations in aqueous solution for parenteral administration to patients. 
     SUMMARY OF THE INVENTION 
     It is a main object of the present invention to administer to patients multivitamins and trace elements together as one entity in an infusion mixture. Heretofore such administration was not possible due to the instantaneous reaction of trace elements with several of the vitamins forming darkly colored, turbid solutions with heavy precipitation occuring within minutes. Examples of such undesirable reactions include reaction of copper with vitamin C, riboflavin, folic acid and vitamin B 12 . 
     It is another object of the present invention to provide a multivitamin/trace elements formulation which is stable for at least 4 to 8 hours at room temperature or 12 to 24 hours refrigerated so as to allow normal manipulative time in hospital infusion. 
     It has been surprisingly discovered that the rapid inter-reactions between vitamins and trace elements can be prevented by the use of a water soluble, organic acid that contains carbon-to-carbon unsaturation and water soluble salts thereof. Such organic acids include: maleic acid, fumaric acid, maleamic acid and acrylic acid. Water soluble saturated weak organic acids, such as citric acid, acetic acid, tartaric acid, gluconic acid, succinic acid, lactic acid, and oxalic acid showed no stabilizing effects. Cyanoacetic acid which has an unsaturated carbon to nitrogen bond was also ineffective in stabilizing the multivitamin/trace elements formulations. 
     In accordance with this discovery, several embodiments of the invention are provided as will be described hereunder. 
     a. One embodiment of the present invention lies in an injectable, two compartment, one unit vial or syringe, aqueous liquid-liquid preparation of multivitamins/trace elements maintained separately, one of the two compartments, in addition to containing the active ingredients, contains a sufficient amount of a water soluble organic acid having carbon-to-carbon unsaturation to stabilize the injectable combination preparation. 
     b. Still another embodiment of the present invention is the same as that described in (a) except the container is a two-unit vial or syringe package. 
     c. A further embodiment of the present invention provides for lyophilization of the respective solution or solutions referred to in (a) and (b) which are reconstituted prior to infusion. 
     The stabilizer can be added separately or combined with either multivitamins or trace elements. 
     The various embodiments of the present invention are useful for adult, pediatric, neonatal or TPN regimen and also for veterinary application. 
     It has been found that a molar ratio of 3 to 30 times of stabilizer to combined trace elements is necessary to effectively stabilize either the multivitamin or the trace elements containing solution which corresponds to about 0.5 to 5.0% w/v of stabilizer in the solution. The preferred method of stabilization is the use of 5 to 10 molar ratio of the water soluble unsaturated organic acid in the trace elements solution. While the mechanism of stabilization is not understood, it is postulated that stabilization is due to weak bonding of the trace element(s) to the unsaturated carbon-carbon (double) bond. 
     DETAILED DESCRIPTION OF THE INVENTION 
     In general, the multivitamin/trace elements formulations of the present invention are directed by therapeutic considerations based on judgements of those skilled in the art of nutrition. For special deficiencies additional components or amounts may be added. Tables I and II show the amounts of the various vitamins and trace elements considered advantageous for use in TPN formulations. 
     
                       TABLE I______________________________________Vitamin Range                              PreferredActive   Forms          Broad Range                              Range*______________________________________Vitamin A,    alcohol, palmitate,                     230-10,000                              3,300-5,000IU       acetateVitamin B.sub.1,    hydrochloride, 0.05-45.0  3.0-6.0mg       mononitrate,    phosphate estersVitamin B.sub.2,    riboflavin,    0.07-10.0  3.0-6.0mg       riboflavin-5-phosphate    sodium saltVitamin B.sub.6,    hydrochloride  0.04-12.0  4.0-6.0mgVitamin C,    Vitamin C, sodium                      4-1,000 100-200mg       ascorbateVitamin D,    ergocalciferol,                     44-1,000 200-400IU       calciferolVitamin E,    d or dl tocopheryl,                   0.66-10     5-10IU       d or dl tocopheryl    acetateNiacinamide,    niacinamide,   0.25-100   40-60mg       niacinPantothenic    d-panthenol,   0.3-25     10-15Acid, mg calcium pantothenateVitamin K,    phytonadione,  0.04-1.0   0.10-0.5mg       menadiole, menadione    bisulfite,    menadiol phosphateBiotin, mcg    biotin          10-100    25-60Folic Acid,    folic acid, sodium                    5-800     400-600mcg      folateVitamin  cyanocobalamin,                   0.04-10    2-5B.sub.12, mcg    cobalamin, hydroxy    cobalamin______________________________________ *Preferred Range for adult formula 
    
     
                       TABLE II______________________________________Trace Element RangeActive  Forms       Broad Range Preferred Range*______________________________________Zinc    chloride, sulfate,               100 mcg-    3-6    mg   acetate, citrate,               10 mg   lactate, nitrate,   tartrateCopper  chloride, sulfate,               20 mcg-     0.4-1.5                                  mg   acetate, nitrate,               2.8 mg   gluconateManganese   chloride, sulfate               2 mcg-      0.15-0.80                                  mg   acetate, nitrate               2.5 mgChromium   chloride, sulfate,               0.14 mcg-   10-15  mcg   acetate, nitrate               20 mcg______________________________________ *Preferred Range for adult formula 
    
     In addition to the active ingredients of vitamins and trace elements, excipients conventionally used in infusable solutions can be used, illustrative examples and amounts of which are shown in Table III. 
     
                       TABLE III______________________________________Excipients______________________________________Antioxidants and       thiourea, thioglycerol, thiosorbitol,Stabilizers cysteine, glycine, sodium formaldehyde(0.005-2.0% w/v)       sulfoxylate, butylated hydroxyanisole,       butylated hydroxytoluene,       nordihydrogluaiaretic acid, ethyl       hydrocaffeate, gentisic acid ethonalamide,       propyl gallate, ascorbyl palmitate, iron       salts.Solvents    propylene glycol, glycerin, alcohol,(0.01 to 30% w/v)       polyethylene glycol.Solubilizers       polyoxylated sorbitol fatty acid esters,(0.01 to 5% w/v)       polyoxylated vegetable oils.Preservatives       (for multidose units) parabens, chlorbutanol,(0.01 to 1.0% w/v)       phenol, benzyl alcohol.______________________________________ 
    
     The multivitamin/trace elements formulations of the present invention may be prepared using commercially available ingredients by methods well-known in the prior art. (Suppliers of raw materials include Hoffman-LaRoche Co., R. W. Greef &amp; Co., H. Reisman Corp., Roussel Corp. and Rhone Poulenc Inc.) 
    
    
     The following examples will illustrate formulations according to the present invention. 
     EXAMPLE 1 (Adult) 
     Ten grams of maleic acid is dissolved in 900 mL of water for injection. To this is added 
     0.536 g: copper chloride (2H 2  O), 
     1.68 g: zinc chloride, 
     0.364 g: manganese chloride (4H 2  O) 
     10.25 mg: chromium chloride (6H 2  O). 
     The mixture is stirred until the solution is dissolved and adjusted to 1 liter volume. 
     Five mL of this mixture containing 
     1.0 mg: copper 
     4.0 mg: zinc 
     0.5 mg: manganese 
     10 mcg: chromium 
     is added to a vial of lyophilized or liquid multivitamin solution containing the following vitamins per unit dose: 
     3,300 IU: vitamin A 
     200 IU: vitamin D 
     10 IU: vitamin E 
     0.15 mg: vitamin K 1   
     6.0 mg: thiamin 
     3.6 mg: riboflavin 
     6.0 mg: pyridoxine 
     40 mg: niacinamide 
     60 mcg: biotin 
     5.0 mcg: vitamin B 12   
     15.0 mg: pantothenic acid 
     600 mcg: folic acid 
     200 mg: ascorbic acid. 
     EXAMPLE 2 (Adult) 
     Five grams of fumaric acid is dissolved in 900 mL of water for injection and 
     1.18 g: copper sulfate (5H 2  O), 
     3.54 g: zinc sulfate (7H 2  O), 
     0.307 g: manganese sulfate (H 2  O); and 
     15.04 mg: chromium sulfate are added and dissolved. 
     The solution is then brought to 1 liter volume. A 5 mL aliquot is taken containing 
     1.5 mg: copper 
     4 mg: zinc 
     0.5 mg: manganese 
     10 mcg: chromium 
     and is added to a liquid or lyophilized multivitamin mixture for infusion purposes, the multivitamin mixture containing the following vitamins: 
     3,300 IU: vitamin A 
     200 IU: vitamin D 
     10 IU: vitamin E 
     3.0 mg: thiamin 
     3.6 mg: riboflavin 
     4.0 mg: pyridoxine 
     40 mg: niacinamide 
     60 mcg: biotin 
     5.0 mcg: vitamin B 12   
     15.0 mg: pantothenic acid 
     400 mcg: folic acid 
     100 mg: ascorbic acid. 
     EXAMPLE 3 (Adult) 
     Twenty grams of tris maleate is added to 900 mL of water for injection and stirred to dissolve. Then the following trace elements are added and dissolved: 
     0.79 g: copper sulfate (5H 2  O), 
     2.1 g: zinc chloride, 
     0.144 g: manganese chloride (4H 2  O), and 
     10.25 mg: chromium chloride (6H 2  O). 
     The solution is q.s. to 1.0 liter and 5 mL aliquot containing 
     1.0 mg: copper 
     5 mg: zinc 
     0.2 mg: manganese 
     10 mcg: chromium 
     is mixed with one unit dose of multivitamin solution for infusion delivery. The vitamin concentration is shown in Example 1. 
     EXAMPLE 4 (Adult) 
     Twenty five grams of maleic acid is dissolved in 900 mL water and 
     1.072 g: copper chloride (2H 2  O), 
     2.52 g: zinc chloride, 
     0.144 g: manganese chloride (4H 2  O), 
     10.25 mg: chromium chloride (6H 2  O) 
     are added and dissolved. The solution is q.s. to 1.0 liter. Five mL aliquot containing 
     2 mg: copper 
     6 mg: zinc 
     0.2 mg: manganese 
     10 mcg: chromium 
     is added to a unit vial of multivitamin of lyophilized multivitamin solution. This is mixed for subsequent addition to the infusion solution. The concentration of vitamins is the same as that shown in Example 1. 
     EXAMPLE 5 (Adult) 
     Twenty grams of sodium maleate is dissolved in 900 mL water for injection. To this is added 
     0.5366 g: copper chloride (2H 2  O), 
     1.68 g: zinc chloride, 
     0.364 g: manganese chloride (4H 2  O), 
     10.25 mcg: chromium chloride (6H 2  O). 
     This mixture is stirred until solution is complete and adjusted to 1 liter. Five mL of this mixture, containing the same concentration of trace elements as Example 1, is added to a unit vial of lyophilized or liquid multivitamins. 
     The composition of the multivitamin mixture used in this example is 
     3,300 IU: vitamin A 
     200 IU: vitamin D 
     10 IU: vitamin E 
     3.0 mg: thiamin 
     3.6 mg: riboflavin 
     4.0 mg: pyridoxine 
     40 mg: niacinamide 
     60 mcg: biotin 
     5.0 mcg: vitamin B 12   
     15.0 mg: pantothenic acid 
     400 mcg: folic acid 
     100 mg: ascorbic acid 
     2.5 mg: thiourea. 
     EXAMPLE 6 (Pediatric) 
     Five grams of maleic acid is dissolved in 900 mL water for injection and 
     0.161 g: copper chloride (2H 2  O), 
     0.63 g: zinc chloride, 
     0.072 g: manganese chloride (4H 2  O), and 
     2.05 mg: chromium chloride (6H 2  O) 
     are added and dissolved. The solution is brought to 1 liter. 
     Five mL of this mixture containing 
     0.3 mg: copper 
     1.5 mg: zinc 
     0.1 mg: manganese 
     2 mcg: chromium 
     is added to a unit vial of lyophilized or liquid pediatric multivitamin solution. The composition of multivitamin pediatric solution is 
     2,300 IU: vitamin A 
     400 IU: vitamin D 
     7 IU: vitamin E 
     0.2 mg: vitamin K 1   
     17 mg: niacinamide 
     1.4 mg: riboflavin 
     1.2 mg: thiamin 
     1.0 mg: pyridoxine 
     5.0 mg: pantothenic acid 
     80 mg: ascorbic acid 
     20 mcg: biotin 
     1.0 mcg: vitamin B 12   
     140.0 mcg: folic acid. 
     EXAMPLE 7 (NEONATAL) 
     2.5 grams of maleic acid is dissolved in 900 mL water for injection and 
     0.032 g: copper chloride (4H 2  O), 
     0.25 g: zinc chloride, 
     0.014 g: manganese chloride (4H 2  O), and 
     0.61 mg: chromium chloride (6H 2  O) 
     are added and dissolved. The solution is q.s. to 1 liter and 5 mL of this mixture containing 
     0.06 mg: copper 
     0.6 mg: zinc 
     0.02 mg: manganese 
     0.6 mcg: chromium 
     is added to a unit vial of lyophilized or liquid multivitamin containing the following vitamins: 
     1,400 IU: vitamin A 
     200 IU: vitamin D 
     4 IU: vitamin E 
     0.1 mg: vitamin K 1   
     10 mg: niacinamide 
     0.8 mg: riboflavin 
     0.7 mg: thiamin 
     0.6 mg: pyridoxine 
     3.0 mg: pantothenic acid 
     50 mg: vitamin C 
     12 mcg: biotin 
     0.6 mcg: vitamin B 12   
     90.0 mcg: folic acid. 
     EXAMPLE 8 (Adult) 
     0.536 g: copper chloride (2H 2  O), 
     1.26 g: zinc chloride, 
     0.144 g: manganese chloride (4H 2  O), 
     10.25 mg: chromium chloride (6H 2  O) 
     are dissolved in 900 mL water for injection. The solution is adjusted to pH 2 with hydrochloric acid and the volume is brought to 1 liter. 
     5 mL of this mixture containing 
     1.0 mg: copper 
     3.0 mg: zinc 
     0.2 mg: manganese 
     10 mcg: chromium 
     is added to a unit vial of lyophilized or liquid multivitamins containing the following vitamins: 
     3,300 IU: vitamin A 
     200 IU: vitamin D 
     10 IU: vitamin E 
     0.15 mg: vitamin K 1   
     6.0 mg: thiamin 
     3.6 mg: riboflavin 
     6.0 mg: pyridoxine 
     40 mg: niacinamide 
     60 mcg: biotin 
     5.0 mcg: vitamin B 12   
     15.0 mg: pantothenic acid 
     600 mcg: folic acid 
     200 mg: ascorbic acid 
     1% w/v: maleic acid 
     0.3 mg: iron peptonate 
     1.0 mg: disodium edetate 
     Physical stability data of a multivitamin formulation containing the vitamins of Table I in the presence of trace elements of Table II are shown in Table IV. In one set of experiments no stabilizer was used; in another set of experiments the water soluble saturated, weak organic acid stabilizers (citric, acetic, tartaric, gluconic, succinic, lactic, oxalic acids) were used; while in the third set of experiments, maleic acid was used as the stabilizer. 
     
                                           TABLE IV__________________________________________________________________________Physical Stability             Saturated Weak                        Maleic AcidTime   No Stabilizer             Organic Acids                        Stabilizer__________________________________________________________________________Initial  Turbid     Turbid     Clear(15 seconds)  Severe darkening             Severe darkening                        Very slight color                        change2 Hours  Slight precipitation             Slight precipitation                        Clear, no precipitateRoom temp.  Severe darkening             Severe darkening                        No further color                        change4 Hours  Moderate precipitation             Moderate precipitation                        Clear, no precipitateRoom temp.  Severe darkening             Severe darkening                        No further color                        change8 Hours  Heavy reddish brown             Heavy reddish brown                        Clear, no precipitateRoom temp.  precipitate             precipitate                        No further color  Severe darkening             Severe darkening                        change24 Hours  Heavy reddish brown             Heavy reddish brown                        Clear, no precipitateRoom temp.  precipitate             precipitate                        Slight color change  Severe darkening             Severe darkening                        from original24 Hours  Heavy reddish brown             Heavy reddish brown                        Clear, no precipitateRefrigerated  precipitate             precipitate                        No color change  Severe darkening             Severe darkening                        from original__________________________________________________________________________ 
    
     Table V shows results of chemical stability tests conducted on vitamin C, vitamin B 1 , folic acid, and vitamin B 12  contained in a multivitamin formulation according to Table I in the presence of the trace elements of Table II. In one set of experiments the unsaturated water soluble acid stabilizer was used, while in another set of experiments the stabilizer was omitted. The remainder of the vitamins of Table I, namely, niacinamide, vitamin B 6 , vitamin B 2 , biotin, vitamin K, pantothenic acid, and vitamins A, D and E were found to be relatively stable in the presence of the trace elements without the presence of stabilizers. 
     
                       TABLE V______________________________________Chemical Stability         No Stabilizer                  Stabilizer______________________________________Vitamin C% Loss2 Hrs. RT       14         44 Hrs. RT       23         56 Hrs. RT       30         58 Hrs. RT       40         524 Hrs. RT      93         1224 Hrs. Refrig  61         5Vitamin B.sub.1% Loss2 Hrs. RT        6         04 Hrs. RT       14         26 Hrs. RT        8         78 Hrs. RT       15         424 Hrs. RT      16         324 Hrs. Refrig  11         1Folic Acid% Loss2 Hrs. RT        9         34 Hrs. RT       10         36 Hrs. RT       --         28 Hrs. RT       --         524 Hrs. RT      43         224 Hrs. Refrig  38         0Vitamin B.sub.12% Loss2 Hrs. RT       --         --4 Hrs. RT       66         16 Hrs. RT       --         --8 Hrs. RT       100        024 Hrs. RT      100        724 Hrs. Refrig  --         --______________________________________ 
    
     The preceeding specific embodiments are illustrative of the practice of the invention. It is to be understood, however, that other expedients known to those skilled in the art or disclosed herein, may be employed without departing from the spirit of the invention or the scope of the appended claims.