the present invention concerns osteoporosis treatment and prevention , which osteoporosis is associated with decreased cortical bone mineral density in mammals generally , but is especially suited for the treatment and prevention of such osteoporosis in humans . for the present invention purposes , mammals includes all mammals within the taxonomic orders of primates , carnivora , perissodactyla and artiodactyla . this includes , without limitation , old world monkeys , new world monkeys , great apes , humans , cats , dogs , horses , pigs , cattle , sheep , and goats . preferably mammals are selected from the taxonmic orders of primates , carnivora , perissodactyla , and artiodactyla , more preferably primates , cats , dogs , sheep , goats , horses , pigs and cattle , still more preferably primates , most preferably humans . igf - i is a naturally occurring protein that can be obtained from a number of sources . preferably , igf - i from the same species ( or its synthetic twin ) as the species being treated therewith is employed , but igf - i from one species may be used to treat another species if the immune response elicited is slight or non - existent . in addition , fragments and analogs of igf - i having igf - i activity , particularly igf - i anti - osteoporosis activity , are also suitably employed in the invention . as used within the context of the present invention igf - i includes such fragments and analogs unless the text clearly states otherwise . where weights of igf - i are presented , that weight of igf - i or an approximately equipotent weight of such analogs and fragments are intended absent clear direction to the contrary . where no type of igf - i is indicated , reference is to human - igf - i ( meaning the structure , not the species source ), unless the reasonable reading of the text requires otherwise . igf - i analogs and fragments of igf - i or its analogs are commonly known in the art as can be seen from proc . natl . acad . sci . usa , vol 83 , pp . 4904 - 4907 , july , 1986 ; biochemical and biophysical research communications , vol 149 , no . 2 , pp . 398 - 404 , dec . 16 , 1987 ; biochemical and biophysical research communications , vol . 149 , no . 2 , pp . 672 - 679 , dec . 16 , 1987 ; endocrinology , vol . 123 , no . 1 , pp . 373 - 381 ; the journal of biological chemistry , vol . 263 , no . 13 , pp . 6233 - 6239 , may 5 , 1988 ; and biochemical and biophysical research communications , vol . 165 , no . 2 , pp . 766 - 771 , dec . 15 , 1989 . igf - i can be synthetically produced , chemically or by recombinant techniques , as well as extracted from tissues . recombinant manufacture is preferred . one such recombinant technique is disclosed in ep 123 , 228 , incorporated herein by reference . an effective amount of igf - i for the present invention is an amount sufficient to slow , stop , or reverse the cortical bone mineral density reduction rate in a patient exhibiting cortical bone mineral density reduction . throughout the specification where values are given for non - cortical bone tissue they are for purposes of exemplifying the osteoporotic state generally . in the normal healthy 20 - 25 year old human population , bone mineral density in the spine ( using dual photon densitometry ) typically is in the range of 0 . 85 to 1 . 9 g / cm 3 , usually 0 . 9 to 1 . 85 g / cm 3 , and most 1 . 0 to 1 . 8 g / cm 3 ; and in the mid radius and distal radius it is typically 0 . 7 - 1 . 4 g / cm 3 , usually 0 . 75 - 1 . 3 g / cm 3 , and most often 0 . 8 - 1 . 2 g / cm 3 . exemplary non - limiting normal ranges are shown in the figures along with osteoporosis distributions . norms using other techniques will be apparent from the literature and general experience therewith as experience with such techniques grow . of course , it is to be remembered that different sub - populations have different norms in bone mineral density . for example , caucasian women typically differ in this parameter from caucasion men as well as from black women , oriental women , and women of other racial types . it is also important to remember that the present invention is directed to treating those with bone mineral which is ( a ) totally below either the normal bone mineral density range for the population generally or for the patient sub - population or ( b ) below 1 . 0 g / cm 3 or ( c ) below the fracture threshold ( approximately 2 standard deviations below the mean bone mass for the population at age 35 ). the fracture threshold for the spine , for example , is defined as the bone mineral density value below which 90 % of all patients with one or more compression fractures of the spine are found . ( see mayo clin . proc ., december 1985 , vol 60 , p . 829 - 830 ). in addition , anyone who demonstrated a statistically significant reduction in bone density over a previous measurement , regardless of where that patient is in the typical ranges above , is a patient to whom the present invention treatment is directed . statistical significance in this context will vary with the technique employed to measure bone mineral density , as well as with the sensitivity of the instruments used . however , with instrumentation and techniques generally available in 1988 , a 1 or 2 % change in bone mineral density from the earliest measurement to the most recent is not considered statistically significant . still as techniques and equipment improve , persons of ordinary skill in the field of bone mineral density measurement will revise downward the maximum percent change which is not considered statistically significant . current bone mineral density measurement techniques include dual energy radiography , quantitative computerized tomography , single photon densitometry , and dual photon densitometry . these techniques will be well known to those of ordinary skill in the art ; however , descriptions thereof can be found in : mayo clin . proc ., december 1985 , vol . 60 , p . 827 - 835 ; orthopedic clinics of north america , vol . 16 , no . 3 , july 1985 , p . 557 - 568 ; hologic qdr ™- 1000 product literature ; annals of internal medicine , 1984 , 100 : 908 - 911 ; and clinical physiol 4 : 343 , 1984 . notwithstanding the lack of statistical significance of a particular result , any bone mineral density reduction should be followed for further reductions , which cumulatively may be significant . usually , an effective amount of igf - i , when given parentally ( intravenously , subcutaneously , intramuscularly , etc .) is between 2 . 5 μg / kg / day up to about 180 μg / kg / day , preferably about 5 μg / kg / day up to about 150 μg / kg / day , more preferably 10 μg / kg / day up to about 120 μg / kg / day , even more preferably 10 μg / kg / day up to about 100 μg / kg / day , still more preferably about 10 μg / kg / day up to about 90 μg / kg / day . when given continuously , such effective amount may be given in two or three doses spread over time such as by iv drip or subcutaneous injection ( s ) with the total daily dose being spread across a portion or the entire administration period . typical continuous dosing is in the range of 2 . 5 μg / kg / hour up to about 50 μg / kg / hour , preferably about 5 μg / kg / hour up to about 25 μg / kg / hour , although wider ranges of “ continuous ” administration amounts will be apparent to those of ordinary skill in the art . when given by subcutaneous injection , it is most preferably administered from 2 times / wk up to 3 times a day , preferably 3 times a week up to once or twice daily . particularly suitable doses are 10 , 15 , 30 , and 60 μg / kg / day . the specific dosage for a particular patient , of course , has to be adjusted to the degree of response , route of administration , the individual weight and general condition of the patient to be treated , and is finally dependent upon the judgment of the treating physician . in general , the pharmaceutical preparations for use in the present invention comprise an effective amount of igf - i or an active fragment or analog or fragment of an analog thereof together with a pharmaceutically and parentally acceptable carrier or adjuvant . compositions having an approximately 6 day supply typically contain from about 0 . 1 mg to 15 mg , preferably 1 mg to 13 mg , more preferably about 3 mg to about 10 mg , most preferably 5mg to 10 mg of igf - i . the liquid carriers are typically sterile water , approximately physiologic saline , about 0 . 1 m acetic acid , approximately 5 % aqueous dextrose , etc ; preferably sterile water , physiologic saline , or 5 % aqueous dextrose . the carriers and adjuvants may be solid or liquid and may be organic or inorganic . the active compound and the compositions of the invention are preferably used in the form of preparations or infusions for parenteral ( subcutaneous , intramuscular , or intravenous ) administration . such solutions are preferably isotonic aqueous solutions or suspensions which can be prepared before use , for example by reconstituting a lyophilized preparation of the active agent . the pharmaceutical preparations may be sterilized and / or contain adjuvants , for example preservatives , antiinfectives , stabilizers wetting agents , emulsifiers , solubilizers , tonicity regulating agents , and / or buffers . other adjuvants will of course be apparent to those of ordinary skill in the art . other dosage forms and routes of administration for use in the present invention include aerosols and sprays for lung inhalation or as a nasal spray , transdermal patch administration , and buccal administration . the present pharmaceutical preparations , which , if desired , may contain further pharmacologically active or otherwise pharmaceutically valuable substances , especially bone antiresorptives such as estrogen , calcitonin , and bisphosphonates , particularly 3 - aminopropyl - 1hydroxy - 1 , 1 - bisphosphonate , are prepared from their constituent parts by techniques known in the art , for example lyophilization , dissolution , reconstitution , and suspension techniques , among others known to those of ordinary skill . they typically contain from about 0 . 1 % to about 100 % of active ingredient , but especially in the case of a solution from about 1 % to about 20 % and especially in the case of a lyophilizate up to 100 % of active ingredient . fig1 . bone mineral density ( bmd in spine ( l1 - 4 ; measured with use of dual - photon absorptiometry )), midradius , and distal radius ( measured with use of single - photon absorptiometry ) in 76 women with osteoporosis in comparison with age - and sex - adjusted normal range ( 105 women ). shaded areas represent 5th and 95th percentile range of normals . patients with osteoporosis are indicated by the dots . note incomplete separation of the two populations . spinal measurements result in the best distinction of patients with osteoporosis from normal subjects because this disease primarily affects trabecular bone of the spine . fig2 . fracture threshold for spinal bone mineral ( horizontal line ) superimposed on normal range ( shaded area ) and values for 76 patients with osteoporosis ( dots ), as depicted in fig1 . with progressing age , values of increasing numbers of normal subjects are below the fracture threshold . fracture threshold is approximately two standard deviations below mean bone mass at 35 years of age . fig1 and 2 are taken from mayo clin . proc ., vol . 60 , december 1985 , mentioned above , and are based on data from riggs b l , wahner h w , dunn w l , mazess r b , offord k p , melton l j iii : differential changes in bone mineral density of the appendicular and axial skeleton with aging : relationship to spinal osteoporosis , j . clin . invest . 67 : 328 - 335 , 1981 . fig3 . a . normal male values for vertebral cancellous mineral content by qct , using cubic regression with 95 % confidence intervals . the cubic regression gives only a slightly better fit to the data for men than does a linear regression ( p & lt ; 0 . 15 ). b . normal female values for vertebral cancellous mineral content by qct , using cubic regression with 95 % confidence intervals ( p & lt ; 0 . 05 ). an accelerated loss is observed after menopause . fig4 . a and b . the accuracy of single - energy qct is shown for vertebral specimens ( preserved in sodium azide ) from 11 patients ( 10 men and 1 woman ), ages 40 - 90 years . fig5 . values for men with idiopathic osteoporosis and spinal fractures are plotted ( black dots ) against the normal male curve ( cubic regression with 95 % confidence intervals ). a fracture threshold at approximately 11 mg / cm 3 is observed . fig6 . idiopathic osteoporotic male values showing larger decrement from normal for vertebral mineral qct than for mean peripheral cortical mineral by radiogrammetry and photon absorptiometry . fig3 - 6 are taken from orthopedic clinics of north america , vol 16 no 3 , july 1985 , mentioned above . having fully described the instant invention , the following examples are presented to more clearly set forth the invention without imposing any limits on the scope of the invention as set out in the claims . sterile , filtered 1 %( w / v ) aqueous solution of igf - i is added , in the amount indicated to the respective dry ampules set forth below . the solution is then lyophilized to result in the dry ampules for reconstitution . the ampules are reconstituted with the indicated amount of sterile water , physiologic saline , 0 . 1 m acetic acid , or 5 % aqueous dextrose to result in a reconstituted solution having the total volume as shown below . each vial is sufficient for a 6 day course of treatment for the intended patient . 6 beagles per group are used to demonstrate the ability of igf - i to improve cortical bone density after loss of ovarian function . one group is given a sham operation to serve as a control . 4 other groups are oophorectomized . of these 4 , one group is treated with igf - i immediately , one is given igf - i after bone growth function has been reduced , one is treated with estrogen and one is followed without treatment . each group is followed for a period of 12 months and bone mineral density ( bmd ) of the vertibral ( trabecular ) and femoral ( cortical ) bones are measured . the results , reported as average changes per group over the 8 month period are reported in table i below . not only did the treatment with igf - i both prophylactically and therapeutically completely wipe out any loss in cortical bone growth associated with oophorectomy , it pushed cortical bone growth beyond the levels which were achieved by the sham operated controls by more than twice those values and beyond that achieved by estrogen by more than 4 . 5 times .
a method for the treatment or prevention of osteoporosis in higher mammals is disclosed , the method comprising administering insulin - like growth factor i in an effective amount thereof to said mammal , said mammal being in need of said treatment or prevention . compositions for pharmaceutical use in the above method are also described .