a readily - soluble freeze - dried solid preparation of hgh with a minimal content of degradation products in terms of deamidation , dimers , polymers , and sulphoxide forms , obtainable by a method comprising a single lyophilization of an aqueous slurry of an amorphous hgh isoprecipitate , the slurry having a ph of from about 4 . 7 to 5 . 0 and being essentially free of buffer components other than acetate .