the present invention will be further illustrated by way of example , and is not intended to limit the present invention thereto . 75 . 00 g of isoniazid , 2 . 00 g of sodium chloride , 18 . 70 g of microcrystalline cellulose , and 10 . 30 g of crosslinked sodium carboxymethyl cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . a flexible material was made by the use of 2 % hydroxypropyl methyl cellulose , and then was passed through a sieve with a pore size of 0 . 710 mm and granulated . the mixture was dried at 50 ° c . until the water content of the granules was less than 3 . 0 %. 1 % by weight of magnesium stearate on the dry granule basis was added . the mixture was further mixed and passed through a sieve with a pore size of 0 . 85 mm , and then was mixed homogenously and compressed to form a tablet by a 4 * 9 mm stamping die with specific shape . the pressure was controlled at 50 to 65 n . the disintegration time of the tablet core before coating is most preferably controlled within 1 minute . a coating solution in a solid content of 15 % was prepared according to the solid content weight ratio of aquacoat ecd : triethyl citrate ( tec ): kollicoat ® ir = 8 . 05 : 2 . 01 : 0 . 50 . the temperature of the coating bed was controlled in the range of 39 ° c . to 42 ° c . the weight gain was 8 to 10 %. the mixture is cured at 60 ° c . for 2 hours after coating , and was ready to use as the inner core of the coated tablet with coated core . the releasing profile of isoniazid in the inner core of the coated tablet with coated core is shown in table 1 . 150 . 00 g of rifampicin , 400 . 00 g of pyrazinamide , 275 . 00 g of ethambutol hydrochloride , 160 . 00 g of microcrystalline cellulose and 54 . 00 g of low - substituted hydroxypropyl cellulose were mixed homogenously , and then formed into powder . the mixture was passed through a sieve with a pore size of 0 . 250 mm , and granulated by the use of 5 % hydroxylpropyl methyl cellulose . the mixture was dried at 50 ° c ., and the moisture of the granules was controlled less than 3 %. 0 . 5 % of finely - divided silica gel on the dry granule basis was added , and the mixture was passed through a sieve with a pore size of 0 . 600 mm . the resulting product was compressed to the coated tablet with coated cores . a 20 % concentration of opadry ii coating solution was prepared . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. 75 . 00 g of isoniazid , 18 . 70 g of microcrystalline cellulose , 8 . 20 g of crosslinked sodium carboxymethyl cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . a flexible material was made by the use of 2 % hydroxypropyl methyl cellulose , and then passed through a sieve with a pore size of 0 . 710 mm and granulated . the mixture was dried at 50 ° c . until the water content of granules was less than 3 . 0 %. 1 % of magnesium stearate on the dry granule basis were added . the mixture was mixed and passed through a sieve with a pore size of 0 . 85 mm , and then was mixed homogenously and compressed to form a tablet by a round stamping die with a 6 . 5 dimple . the pressure was controlled at 50 to 65 n . the disintegration time of the tablet core before coating is optimum within 1 minute . a coating solution in a solids content of 15 % was prepared according to the solid content weight ratio of aquacoat ecd : triethyl citrate ( tec ): kollicoat ® ir = 8 . 05 : 2 . 01 : 0 . 50 . the temperature of the coating bed was controlled in the range of 39 ° c . to 42 ° c . the weight gain was 8 to 10 %. the mixture is cured at 60 ° c . for 2 hours after coating , and was ready to use as the inner core of the coated tablet with coated core . the releasing profile of isoniazid in the inner core of the coated tablet with coated core is shown in table 2 . 3 ) the compression and coating of the coated tablet with coated core the outer layer granules in example 1 were used to compress the coated tablet with coated core , the resulting tablet was coated with 20 % concentration of opadry ii coating solution . the temperature of the coating materials was controlled in the range of 40 to 45 ° c . the weight gain was about 3 %. 75 . 00 g of isoniazid , 18 . 70 g of microcrystalline cellulose , 8 . 20 g of crosslinked sodium carboxymethyl cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . a flexible material was made by the use of 2 % hydroxypropyl methyl cellulose . first , isoniazid was grinded and passed through a sieve with a pore size of 0 . 250 mm . the mixture was extruded with a sieve with a pore size of 600 μm . the mixture was rounded at 700 rpm , and then produced as pellets . the pellets were dried at 50 ° c . a coating solution in a solid content of 15 % was prepared according to the solid content weight ratio of aquacoat ecd : triethyl citrate ( tec ): kollicoat ® ir = 8 . 05 : 2 . 01 : 0 . 50 . the temperature of the coating bed was controlled in the range of 39 ° c . to 42 ° c . the weight gain of the coating of pellets was 22 to 25 %. the mixture is cured at 60 ° c . for 2 hours after coating , and was ready to use as the inner core of the coated tablet with coated core . 3 ) the compression and coating of the coated tablet with coated core the outer layer granules in example 1 were used to compress to form a tablet according to the ratio of isoniazid : rifampicin : pyrazinamide : ethambutol hydrochloride in 75 mg : 150 mg : 400 mg : 275 mg , the resulting tablet was coated with 20 % concentration of opadry ii coating solution . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. 30 . 03 g of isoniazid , 5 . 60 g of microcrystalline cellulose , 7 . 40 g of crosslinked sodium carboxymethyl cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with a 2 % hydroxypropyl methyl cellulose solution . the mixture was dried at 50 ° c . until the water content of granules was less than 3 . 0 %. 0 . 5 % of finely - divided silica gel was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . 55 . 02 g of ethambutol hydrochloride and 5 . 02 g microcrystalline cellulose were mixed , grinded , and passed through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with an ethanol / water solution of 5 % ethyl cellulose ( ethanol : distilled water = 90 : 10 , v / v ) and was granulated . the mixture was dried at 80 ° c . until the water content of granules was less than 2 . 0 %. 0 . 5 % of stearic acid was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . 15 . 00 g of ethambutol hydrochloride , 80 . 00 g of pyrazinamide and 8 . 02 g microcrystalline cellulose were mixed , grinded , and passed through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with an aqueous solution of 2 % hydroxypropyl methyl cellulose , and granulated . the mixture was dried at 80 ° c . until the water content of granules was less than 3 . 0 %. 0 . 5 % of stearic acid was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . rifampicin layer , ethambutol hydrochloride layer , and isoniazid / pyrazinamide layer were compressed to a three - layer tablet according to ratio of rifampicin : ethambutol hydrochloride : isoniazid : pyrazinamide = 150 mg : 275 mg : 75 mg : 400 mg . a 15 % coating solution was prepared according to the solid weight content of aquacoat ecd : dbs : tec : titanium dioxide = 60 : 20 : 10 : 10 . the weight gain of the coating was about 8 %. it was cured at 60 ° c . for 2 h . 30 . 13 g of isoniazid , 5 . 66 g of microcrystalline cellulose , 7 . 50 g of crosslinked sodium carboxymethyl cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with a 2 % hydroxypropyl methyl cellulose solution . the mixture was dried at 50 ° c . until the water content of granules was less than 3 . 0 %. 0 . 5 % of finely - divided silica gel was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . 55 . 22 g of ethambutol hydrochloride , 5 . 99 g microcrystalline cellulose and 3 . 01 g of hydroxylpropyl cellulose k100m were mixed , grinded , and passed through a sieve with a pore size of 0 . 250 mm . a flexible material made by the use of 70 % ethanol / water solution ( v / v ) was passed through a sieve with a pore size of 0 . 710 mm and granulated . the mixture was dried at 80 ° c . until the water content of granules was less than 2 . 0 %. 0 . 5 % of stearic acid was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . 15 . 08 g of isoniazid , 80 . 10 g of pyrazinamide , and 8 . 10 g of microcrystalline cellulose were mixed and grinded to pass through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with a 2 % hydroxypropyl methyl cellulose solution . the mixture was dried at 80 ° c . until the water content of granules was less than 3 . 0 %. 0 . 5 % of stearic acid was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . rifampicin layer , ethambutol hydrochloride layer , and isoniazid / pyrazinamide layer were compressed to a three - layer tablet according to ratio of rifampicin : ethambutol hydrochloride : isoniazid : pyrazinamide = 150 mg : 275 mg : 75 mg : 400 mg . a 15 % coating solution was prepared according to the solid weight content of aquacoat ecd : dbs : tec : titanium dioxide = 60 : 20 : 10 : 10 . the weight gain of the coating was about 8 %. it was cured at 60 ° c . for 2 h . a 15 % coating solution was prepared according to the solid weight content of aquacoat ecd : tec : hpmc : titanium dioxide = 70 . 8 : 12 . 5 : 8 . 3 : 8 . 3 . the weight gain of the coating was about 8 %. it was cured under 60 ° c . for 2 h . 15 . 02 g of isoniazid and 2 . 80 g of microcrystalline cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . a flexible material was made by the use of 2 % hydroxypropyl methyl cellulose , and then passed through a sieve with a pore size of 0 . 710 mm and granulated . the mixture was dried at 50 ° c . until the water content of granules was less than 3 . 0 %. 1 % of magnesium stearate on the dry granule basis were added . the mixture was mixed and passed through a sieve with a pore size of 0 . 85 mm , and then was mixed homogenously and compressed to form a tablet by a 4 * 9 mm stamping die with specific shape . the pressure was controlled at 50 to 65 n . 2 ) the coating of the inner core of the tablet with separating coating film a 10 % hpmc solution was used to coat . the temperature of the coating bed was controlled in the range of 28 ° c . to 32 ° c . the weight gain was about 5 %. 15 . 05 g of rifampicin and 15 . 10 g of hydroxypropyl methyl cellulose acetate succinate were mixed homogenously . the rifampicin solid dispersion was prepared by hot melting method , and then grinded and passed through a sieve with a pore size of 0 . 250 mm . 400 . 70 g of rifampicin , 275 . 05 g of ethambutol hydrochloride , 161 . 04 g of microcrystalline cellulose and 54 . 50 g of low - substituted hydroxypropyl cellulose were mixed homogenously , and then formed into powder . the mixture was passed through a sieve with a pore size of 0 . 250 mm , and granulated with 5 % hydroxylpropyl methyl cellulose . the mixture was dried , and the moisture of the granules was controlled less than 3 %. the rifampicin solid dispersion powders were mixed with dried pyrazinamide / ethambutol hydrochloride granules in step 4 ) according to the ratio of rifampicin : ethambutol hydrochloride : pyrazinamide = 150 mg : 275 mg : 400 mg . a 0 . 5 % of finely - divided silica gel was added based on mixed granules , and passed through a sieve with a pore size of 0 . 600 mm . the resulting product was ready for compression into tablet . the coated tablet in step 2 ) was used as the tablet core , and the granules produced in step 5 ) were used as the outer layer and compressed to the coated tablet with coated core . a 20 % concentration of opadry ii coating solution was prepared . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. 150 . 00 g of rifampicin and 150 . 00 g of hydroxypropyl methyl cellulose acetate succinate were mixed homogeneously , then dissolved in 1500 . 0 g of dichloromethane and 1500 . 0 g acetone respectively , the resulting solutions were mixed homogeneously , and then the rifampicin solid dispersion was prepared by spray drying method . the air blowing temperature was controlled at 50 to 55 ° c . the rifampicin solid dispersion powders prepared by spray drying method were mixed with dried pyrazinamide / ethambutol hydrochloride granules in step 4 ) of example 7 according to the ratio of rifampicin : ethambutol hydrochloride : pyrazinamide = 150 mg : 275 mg : 400 mg . a 0 . 5 % of finely - divided silica gel was added on the mixed granule basis , and passed through a sieve with a pore size of 0 . 600 mm . the resulting product was ready for compression into tablet . the coated tablet in step 2 ) of example 7 was used as the tablet core , and the granules produced in step 2 ) of example 8 were used as the outer layer and compressed to the coated tablet with coated core . a 20 % concentration of opadry ii coating solution was prepared . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. 150 . 00 g of rifampicin and 150 . 00 g of hydroxypropyl methyl cellulose acetate succinate were mixed homogeneously , then dissolved in 1500 . 0 g of dichloromethane and 1500 . 0 g acetone respectively , the resulting solutions were mixed homogeneously for subsequent use . 400 . 00 g of pyrazinamide , 275 . 00 g of ethambutol hydrochloride , 160 . 00 g of microcrystalline cellulose and 54 . 00 g of low - substituted hydroxypropyl cellulose were mixed homogenously , and grinded . the mixture was passed through a sieve with a pore size of 0 . 250 mm , and then poured into a fluidized bed . the rifampicin solution in step 1 ) was used in one - step granulation method . the temperature of the materials was controlled at 35 to 40 ° c ., and the water content of the granules was controlled less than 3 %. a prescription amount of finely - divided silica gel was added , and passed through a sieve with a pore size of 0 . 600 mm . the resulting product was ready for use . the coated tablet in step 2 ) of example 7 was used as the tablet core , and the granules produced in step 2 ) of example 9 were used as the outer layer and compressed to the coated tablet with coated core . a 20 % concentration of opadry ii coating solution was prepared . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. 60 . 30 g of rifampicin solid dispersion in example 8 , 5 . 60 g of microcrystalline cellulose , 7 . 32 g of crosslinked sodium carboxymethyl cellulose were mixed homogenously , and then were grinded to pass through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with a 2 % hydroxypropyl methyl cellulose solution . the mixture was dried at 50 ° c . until the water content of granules was less than 3 . 0 %. 0 . 5 % of stearic acid was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . 55 . 22 g of ethambutol hydrochloride and 6 . 03 g microcrystalline cellulose were mixed , grinded , and passed through a sieve with a pore size of 0 . 250 mm . the mixture was passed through a sieve with a pore size of 0 . 710 mm with an aqueous solution of 5 % hydroxypropyl methyl cellulose and granulated . the mixture was dried at 80 ° c . until the water content of granules was less than 2 . 0 %. 0 . 5 % of stearic acid was added on the dry granule basis , and the mixture was passed through a sieve with a pore size of 0 . 850 mm . the resulting product was mixed homogenously and ready for compression into tablet . 1 ) rifampicin layer , 2 ) ethambutol hydrochloride layer , and 3 ) isoniazid / pyrazinamide layer in example 5 were compressed to a three - layer tablet according to the ratio of rifampicin : ethambutol hydrochloride : isoniazid : pyrazinamide = 150 mg : 275 mg : 75 mg : 400 mg . a 20 % concentration of opadry ii coating solution was prepared . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. 148 . 84 g of rifampicin solid dispersion in example 8 , 20 . 75 g of microcrystalline cellulose , 8 . 94 g carbonoxymethyl cellulose sodium and 0 . 90 g of finely - divided silicone gel were mixed homogenously and compressed to form a tablet by a round stamping die with a 12 dimple . the pressure was controlled at 50 to 90 n . the resulting tablet was coated with a 20 % concentration of opadry ii coating solution . the temperature of the coating materials was controlled at 40 to 45 ° c . the weight gain was about 3 %. the in vivo experimental data of the formulation in the example are shown in tables 10 to 11 . rifampicin solid dispersions with different ratios are prepared by means of solvent spontaneous evaporation method . 9 . 0 , 6 . 0 , 3 . 0 , 1 . 5 and 1 . 0 g of hpmcas were each dissolved in 30 . 0 g of dichloromethane to prepare a solution . and then , the rifampicin solutions were each poured into the hpmcas solution . after mixed homogeneously for 1 h , the mixtures were each poured into watch glasses , and placed in the hood for evaporating to dry . the rifampicin solid dispersions were obtained , and then grinded for use . the measurement results of the release degree of rifampicin in the formulation of the example were shown in table 5 . rifampicin ( shenyang antibiotics factory ); isoniazid ( zhejiang xinsai pharmaceuticals co . ltd . ); pyrazinamide ( jiangsu sihuan biotec co . ltd . ); ethambutol hydrochloride ( shanghai wuzhou pharmaceuticals co . ltd . ); the imported tb4 coated tablet with coated core ( panacea biotec ltd ); rifampicin capsules made in china ( shenyang hongqi pharmaceuticals co . ltd . ); isoniazid tablet made in china ( shenyang hongqi pharmaceuticals co . ltd . ); microcrystalline cellulose ( asahi kasei chemicals corporation ); low - substituted hydroxypropyl cellulose ( shin - etsu ); hydroxypropyl methylcellulose e5 and k100m ( colorcon ); stearic acid ( hunan huari pharmaceuticals co . ltd . ); finely - divided silicone gel ( evonik ); hydroxypropyl methyl cellulose acetate succinate ( shin - etsu ); crosslinked sodium carboxymethyl cellulose ( nichirin chemical industries ltd . ); aquacoat ecd ( fmc biopolymer ); triethyl citrate ( shanghai shenbao flavours and perfumes co . ltd . ); kollicoat ® ir ( basf ); magnesium stearate ( anhui shanhe pharmaceutic adjuvant co . ltd . ); vitamin c ( hebei welcome pharmaceutical co ., ltd ); lauryl sodium sulfate ( anhui shanhe pharmaceutic adjuvant co . ltd . ); peg6000 ( chemical reagents co . ltd ., sinopharm group ); opadry ii ( colorcon ); dichloromethane ( chemical reagents co . ltd ., sinopharm group ); acetone ( chemical reagents co . ltd ., sinopharm group ); sodium chloride ( shanghai qingxi chemical technology co . ltd . ); acetonitrile ( chromatographically pure , merck co . ltd ., us ); anhydrous di - sodium hydrogen phosphate ( analytically pure , shanghai lingfeng chemical reagent co . ltd . ); phosphoric acid ( analytically pure , chemical reagents co . ltd ., sinopharm group ); sodium hydroxide ( analytically pure , shanghai lingfeng chemical reagent co . ltd . ); acetic acid ( analytically pure , shanghai lingfeng chemical reagent co . ltd .). mini - type multi - functional experiment machine ( chongqing jinggong pharmaceutical machine co . ltd . ); single - punch tablet press ( shanghai tianfan pharmaceutical machinery factory ); spray dryer ( buchi ); moisture determination meter ( sartorius co . ltd ., beijing ); intelligent dissolution testing meter ( tianda tianfa co . ltd . ); climatic chamber , type 720 ( binder ); bt224s electronic balance ( sartorius co . ltd ., beijing ); ohhara lab type coating pan ; agilent 1200 hplc ( agilent technology , co . ltd . ); fe20 type ph meter ( mettler toledo co . ltd : phenomenex luna c18 100a ( 250 × 4 . 6 mm , 5 μm , phenomenex co . ltd ., us ); agilent eclipse xdb - c18 ( 150 × 4 . 6 mm , 5 μm , agilent technology , co . ltd ., us ). according to the experimental experience , when the coating film of the tablet was not broken , the release of isoniazid is relatively small , i . e . less than 10 %. therefore , samples of tablet no . 20 and 26 were not sampled and measured . as shown in table 1 , the breaking time of the inner core coating film essentially may be within the required controlled time , i . e . 30 to 60 minutes . after coating film was broken , the drugs could be completely released in a short time . as shown in table 2 , the coating films in the central layer of the formulations each broke within 30 to 60 minutes . within 30 minutes , the release of isoniazid is not more than 2 %, which is much lower than the 10 % standard in the optimized regime for quality control . within 90 minutes , the drug is essentially completely released . from the data in table 3 , it can been seen that the release of isoniazid can achieve the standard required for control , i . e . less than 15 % released within 30 minutes , and more than 80 % released within 90 minutes . from the data in table 3 , it can be seen that the release - controlled film and the ethambutol hydrochloride layer were great for the controlling of the delayed - release of isoniazid . 1 ) the dissolution condition { circle around ( 1 )} is that acid and base ( 900 ml each ) were not contained in the same cup , and it was independently conducted by paddle method in 100 rpm at 37 . 0 ° c . the dissolution condition { circle around ( 2 )} is that acid and base were contained in the same cup . in other words , 750 ml acidic substance ( 0 . 1 mol / l hydrochloric acid ) is firstly added . taking sample and adding solution after it was dissoluted for 45 min , while 250 ml 0 . 2 mol / l sodium phosphate solution was added , and 4 . 5 ml 2 mol / l sodium hydroxide was added to adjust the solution ph to 6 . 8 ± 0 . 05 as the basic media . it was conducted by paddle method in 100 rpm at 37 . 0 ° c . as shown in table 5 , the experiment result indicates that according to the present invention , it has better solubilizing effect for rifampicin by preparing rifampicin to solid dispersions ( rifampicin : hpmcas is 3 : 1 to 1 : 3 ). however , when rifampicin : hpmcas is 3 : 1 , the release of rifampicin in the acidic stomach condition was out of the control range , and thus such a ratio was not selected for preparation . as can be seen in the table , it is most suitable to select the weight ratio of rifampicin : hpmcas in 1 : 1 , since it was solubilized , and the release of rifampicin in acid can be controlled , the amount used was also relatively small . as shown in table 7 , the rifampicin stability order of the three preparation method for solid dispersions is spontaneous evaporation method & gt ; spray drying method & gt ; hot melting method . combined with the industrialized character for production , spray drying method is preferred . the stability investigation result in table 8 indicates that the inventive product is more stable than the imported commercially available product . therefore , the present invention facilitates to improve the stability of the four - ingredient combined anti - tubercular formulation . as shown in table 9 , the stability investigation result for a 12 - month long term indicates that when left under normal temperature , the impurities due to rifampicin and isoniazid increased in the inventive formulations in the investigation period , but the formulation is still relatively stable . 12 beagles were randomly divided into groups a and b . each was fed at 8 a . m ., and administrated after 0 . 5 h . group a were administrated with one tablet of the inventive rifampicin tablet ( 150 mg , corresponding to 10 mg / kg , rifampicin firstly formed to enteric solid dispersions by spray drying , and then compressed with other adjuvants to produce a coated sample ( i . e . sample of example 11 ). group b were administrated with one pill of the rifamipicin capsule produced by shenyang hongqi pharmaceutical co . ltd . ( 150 mg , batch no . 0907011 ). two weeks after the end of the above experiment , each of groups a and b was fed , and administrated after 0 . 5 h . group a were administrated with one tablet of the inventive rifampicin tablet ( 150 mg , corresponding to 10 mg / kg , the sample is the same as the single administration sample ) and one tablet of the isoniazid produced by shenyang hongqi pharmaceutical co . ltd . ( 75 mg / pill , produced by grinding the tablet containing 0 . 3 g / tablet of batch no . 0907011 and canning ). group b were administrated with one pill of the rifamipicin capsule ( 150 mg , batch no . 0907011 ) and one pill of isoniazid ( same as group a ) produced by shenyang hongqi pharmaceutical co . ltd . from the data of auc 0 - 24 h and auc 0 -∞ h in table 10 and table 11 , it can be seen that after rifampicin is produced to solid dispersion , its bioavailability is significantly increased . it will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof . it is understood , therefore , that this invention is not limited to the particular embodiments disclosed , but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims .
provided is an oral solid preparation of a compound anti - tubercular drug , wherein the active ingredients are rifampicin , isoniazid , pyrazinamide and ethambutol hydrochloride . the compound oral solid preparation is a coated tablet with coated core or a coated three - layer tablet , wherein the two active ingredients rifampicin and isoniazid do not come to contact with each other directly . the compound oral solid preparation not only improves the stability of the compound preparation , but also improves the bioavailability of rifampicin .