US 20060094700A1 (19) United States (12) Patent Application Publication (10) Pub. No.: US 2006/0094700 A1 Lyons (43) Pub. Date: May 4, 2006 (54) HEAT STERILIZATION OF A STEROID IN (22) Filed: Nov. 2, 2004 THE PRESENCE OF PHOSPHATE Publication Classi?cation (75) Inventor: Robert T. Lyons, Laguna Hills, CA (Us) (51) Int. Cl. A61K 31/5 73 (2006.01) Correspondence Address: (52) US. Cl. ............................................................ .. 514/179 ALLERGAN, INC., LEGAL DEPARTMENT 2525 DUPONT DRIVE, T2-7H (57) ABSTRACT IRVINE CA 92612-1599 US a ( ) A process for sterilizing a Water-insoluble steroid composi (73) Assigneej ALLERGAN, INC" Irvine’ C A (Us) tion comprising heat sterilizing the steroid in the presence of phosphate is disclosed herein. Compositions related thereto (21) Appl. No.: 10/980,026 are also disclosed. Effect of Additives on Particle Size Distribution of 20% Triamcinolone Aqueous Suspensions After Autoclaving 25 l I I l E -Mean =- zo- E9001 P'tile . 1:“ .2 ‘I 5 \ g 15- - a .2 n g 10- . (D 2 .2 t 5- - N n- I c I Non-Aut'oclaved Autocl I+ None Autocl'+ NaCl Autocl + NaCl + PQ Additives to Triamcinolone Acetonide Suspension Patent Application Publication May 4, 2006 US 2006/0094700 A1 Figure 1 Effect of Additives on Particle Size Distribution of 20% Triamcinolone Aqueous Suspensions After Autoclaving a: l I I l ‘v E -Mean =5 20- 90th P'tile . .5 ‘I g \ I: 15" ' H .2 D .8 10- - w 2 .2 ‘E 5- - N n- o I Non-Aut'oclaved Autocl I+ None Autocl'+ NaCl Autocl + NaCl + Pq Additives to Triamcinolone Acetonide Suspension US 2006/0094700 A1 May 4, 2006 HEAT STERILIZATION OF A STEROID IN THE presence of phosphate is disclosed herein. Compositions PRESENCE OF PHOSPHATE related thereto are also disclosed. DESCRIPTION OF RELATED ART [0008] A “Water-insoluble steroid” is a steroid Which is not [0001] Among the therapies currently being practiced to completely dissolved at the concentration at Which it is administered in an aqueous composition. Thus, depending treat ocular posterior segment disorders, such as uveitis, macular degeneration, macular edema and the like, is intra upon the use and concentration, a steroid may be considered Water-insoluble in one situation but not Water-insoluble in vitreal injection of a corticosteroid, such as triamcinolone another situation. While not intending to limit the scope of acetonide (TA). See, for example, Billson et al US. Pat. No. the invention in any Way, typical steroids include estrogens; 5,770,589, the disclosure of Which is incorporated in its entirety herein by reference. One medication commonly glucocorticoids; progestins; mineralocorticoids; corticoster employed for this ophthalmic therapy is Kenalog® 40. oids, such as cortisone, hydrocortisone, prednisone, pred nisolone, methylprednisone, triamcinolone, ?uorometha [0002] Steroid drug suspensions intended for parenteral lone, dexamethasone, medrysone, betamethasone, administration are routinely heat sterilized since ultra?ltra loteprednol, ?uocinolone, ?umethasone, or mometasone; tion is not an option. Change in particles size during the heat and androgens such as testosterone, methyltestosterone, or ?ltration process is often problematic. ZA 665331 discloses danazol. Often steroids are administered as ester, acetal, or [0003] Although drugs in the solid form and sparingly ketal prodrugs, many of Which are Water-insoluble. These soluble in H2O are not generally amenable to heat prodrugs are also considered to be steroids. While not sterilization, heating suspensions of the drugs in H2O intending to limit the scope of the invention in any Way, saturated With NaCl is effective. The process is par triamcinolone actetonide is a steroid Which is Water-in ticularly suitable for steroids. To a partial suspension of soluble in many compositions in Which it is used therapeu 0.8 parts NaCl in 1.6 parts sterile H2O heated to boiling tically. and cooled Was added 0.8 parts dexamethasone acetate [0009] A “prodrug”, as generally understood in the art, is (I) in jetomized form and 0.0075 parts poly(oxyethyl a compound Which is converted to a therapeutically active ene) (20) sorbitan monooleate (II). The mixture Was compound in vivo after administration, and the term should sterilized by autoclaving at 121° 20-30 min. A solution be interpreted as broadly herein as is generally understood in of 0.9 parts PhCHzOH, 0.0675 parts II, 0.5 parts Na the art. While not intending to limit the scope of the CM-cellulose, and 70 parts H2O Was ?ltered, sterilized invention, conversion may occur by hydrolysis of an ester at 121° 15 min., cooled, combined aseptically With the group or some other biologically labile group. foregoing suspension, and diluted to 100 parts With sterile H20. The I crystals shoWed no change of [0010] In the process disclosed herein, heat sterilization particle size. The process Was applied also to predniso may be accomplished at any temperature Which Will kill the lone ter‘t-butylacetate, indomethacin, and tiabendazole. pathogens of importance to the application in Which the [0004] EP1172098 discloses “an autoclavable ophthalmic composition is used. Such a determination can be made composition comprising an ophthalmically effective drug.” Without undue experimentation by a person of ordinary skill The ’098 patent also discloses the folloWing related to the in the art. In some heat sterilization processes, the compo drug “Strongly preferred are ketotifen and dexamethasone.” sition is heated to a temperature of 100° C. or greater. In In relation to the bulfer, the folloWing is disclosed “[e] other processes, the composition is heated to a temperature xamples of bulfer substances are acetate, ascorbate, borate, of 121° C. or greater. hydrogen carbonate/carbonate, citrate, gluconate, lactate, [0011] Heating is carried out for the length of time phosphate, propionate and TRIS (tromethamine) buffers.” required to kill the pathogens of importance to the applica [0005] US. Pat. No. 6,468,548, also published as tion in Which the composition is used. Such a determination WO09936055, EP0938896, and CA2315767, “describes an is Well Within the skill of a person of ordinary skill in the art. autoclavable ophthalmic composition comprising an oph In some processes, the composition is maintained at or near thalmically effective drug.” The ’548 patent further discloses the peak temperature for at least 30 minutes. In other that the compositions “comprise an ophthalmically effective processes, the composition is maintained at or near the peak ingredient and in particular ketotifen or dexamethasone”, temperature for about 45 minutes. In other processes, the and that “[b]ulfers, tonicity enhancing agents and preserva composition is maintained at or near the peak temperature tives different from quaternary ammonium salts may be used for more than 45 minutes. in an ophthalmic composition of the present invention too. [0012] The term “phosphate” refers to phosphoric acid and Examples of bulfer substances are acetate, ascorbate, borate, its salts in any combination, including as individual species. hydrogen carbonate/carbonate, citrate, gluconate, lactate, In other Words, phosphate is phosphoric acid, monovalent phosphate, propionate and TRIS (tromethamine) buffers.” salts of phosphate, divalent salts of phosphate, and trivalent BRIEF DESCRIPTION OF THE DRAWING salts of phosphate, individually or in any combination. FIGURES [0013] The concentration of phosphate used is that [0006] FIG. 1 shoWs the effect of additives on particle size required to improve control of any property related to distribution of triamcinolone acetonide aqueous suspensions particle size, including particle size distribution, average during autoclaving. particle sized, maximum particle size, minimum particle sized, mean particle size, median particle size, particle DESCRIPTION OF THE INVENTION number, and the like. Such a determination can be made by [0007] A process for sterilizing a Water-insoluble steroid a person of ordinary skill in the art. In some processes, the composition comprising heat sterilizing the steroid in the concentration of the phosphate in a composition being US 2006/0094700 A1 May 4, 2006 sterilized is greater than 0.1%. Some compositions comprise in hoW to make and use the invention, and are not intended 0.6% sodium phosphate dibasic and 0.08% sodium phos to limit the scope of the invention in any Way. phate monobasic. In other processes, the Weight ratio of phosphate to steroid is at least 0.01. In other Words, there is EXAMPLE 1 at least 1 mg of phosphate for every 100 mg of steroid. In other processes, the Weight ratio of phosphate to steroid is at [0023] The compositions of FIG. 1 Were prepared by the least 0.03. folloWing procedure. Triamcinolone acetonide slurries Were 20% W/W. These Were prepared either in distilled Water, [0014] In some processes, the steroid is heat sterilized in Water containing 1.58% sodium chloride, or Water contain a composition comprising both phosphate and sodium chlo ing 1.58% sodium chloride plus 0.75% dibasic sodium ride. Some compositions comprise 20% triamcinoline phosphate (heptahydrate) and 0.10% monobasic sodium actetonide, 1.58% sodium chloride, 0.75% sodium phos phosphate (monohydrate). All slurries Were adjusted to pH phate dibasic, and 0.10% sodium phosphate monobasic. 7.3 and then transferred to 10 mL pharmaceutical glass vials ?tted With rubber stoppers and aluminum overseals. Auto [0015] While not intending to limit the scope of the claving Was accomplished in a bench top steam autoclave at invention in any Way, steroids are often used for the treat ment or prevention of conditions affecting the eye. Some 1210 C. for 45 minutes (Brinkmann 2540E). Following compositions prepared by the processes disclosed herein autoclaving, all suspensions Were stirred gently With a magnetic stir bar for about 16 hours at room temperature to may be used for topical ophthalmic purposes. Some com disrupt any loose aggregates of drug crystals. Particle size positions prepared by the processes disclosed herein may be distributions (mean and 90th percentile) Were then measured useful for injection into the eye.