Quality Control Of Sterile Products 5q5t36

Dr. Prafulla Kumar Sahu M.Pharm., Ph.D. Professor Raghu College of Pharmacy Dakamarri, Visakhapatnam, AP, India

QUALITY CONTROL OF STERILE PRODUCTS

Sample Questions Define sterile products. What are the features in sterile products? Define clean area. What are the classifications/specifications for clean areas? Write a detailed of environmental control in sterile area. What do you know about the facilities in clean rooms? What is source of particulate in sterile products? What are several methods for testing of clarity of sterile products? Write detail of production of sterile products. How liquid sterile products are filled into their containers? What are the in-process quality control tests employed on the sterile products? Discuss two methods for the testing of clarity/particulate matter in parenteral preparations? What is purpose and procedure of LAL test? What are the advantages of LAL test over in-vivo test? What is the purpose and procedure of rabbit test?

PYROGEN TESTING Pyrogens produce symptoms of fever, chill, t pain, malaise, headache and other complaints following IV injection within 30-120 minutes which may subside within 10-12 hours. Pyrogens are the heat stable, filterable and soluble substances of 0.05-1.0 micrometer size and arise from microbial contamination. Chemically these are lipopolysaccharides from the outer cell wall of the bacteria, thus, the term endotoxins is also used interchangeably but not correct entirely. Both G+ and G- bacteria produce pyrogens, however, the pyrogens of G- bacteria are more potent. The pyrogens are heat stable up to some extent, thus, withstand normal sterilization temperatures. Depyrogenation Depyrogenation is the removal of pyrogen. This is achieved by the following methods. Inactivation - Application of very high dry heat (2500P) for not less than 30 minutes is the desired method for rendering material pyrogen free. Removal of pyrogen by distillation

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Detection and quantification of Pyrogens 1) In-vivo pyrogen (rabbit) test In-vivo pyrogen test involves the evaluation of the presence of pyrogens in parenteral sample by quantitative fever response produced in rabbits. The principle is based on the fact that the human and rabbits are equally responsive to pyrogen injected intravenously on a dose per weight basis. This test requires the following. Test animals: healthy adult rabbits (of either sex) weighing not less than 1500 gm (1.5kg). The animals have been properly maintained in of environment and diet prior to the performance of test. The animals are screened for their temperature. Their control temperature must not differ more than 1°C from each other. Any individual animal having temperature 39.8°C or less than 38.0°C is excluded from the test. The rabbit-retaining boxes are required to house the rabbits. These boxes "hold" the rabbits so that the temperature can be noted easily during test. The specific directions given in the individual monograph must be followed for the products. The sample to be tested is injected with a slower rate to the animals. The dose of the sample if not specified should be smaller than 10 ml/kg. Special preliminary steps are required and thus, consideration must be given for the products requiring; 1) dilution, 2) pH adjustment, and 3) isotonicity adjustment. PROCEDURE The control (baseline) temperature of three rabbits is determined. The sample is injected into the ear vein of each of three rabbits which are held in the retaining boxes. A dose of 10ml/kg of body weight is used unless specified in the individual monograph. The temperature of each rabbit is determined at 1, 2, and 3 hours subsequent to the injection of sample. The difference between the initial and final temperatures of each rabbits is noted. Any increase in temperature is taken to be the response of sample injected. Interpretation of the results The material under examination meets the requirements for apyrogenicity if no rabbit shows an individual rise in temperature of 0.6°C or more above its respective control temperature OR the sum of the temperature rise of 3 rabbits does not exceed 1.4°C. If the results are not within the limits, the test is repeated for additional 5 rabbits and the result is considered for the eight rabbits. After repeating, the material under examination meets the requirements if not more than 3 out of eight rabbits show individual rise in temperature of 0.6 °C OR the sum of rise in the temperature in eight rabbits does not exceed 3.7°C.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Sometimes the difference of initial and the final temperature is negative. If the difference is negative, the result of the rabbit test is counted as zero response and the sample is considered apyrogenic. Advantages of Rabbit Test The human and rabbits are equally responsive to threshold levels of the pyrogens. 2) Limulus Amebocyte Lysate Test The limulus amebocyte lysate test is also called as in-vitro pyrogen test (USP XXI Specified new test). Officially it is termed as bacterial endotoxin test (BET). The test principle is based on the clotting of lysate of amebocyte (an enzyme obtained from the horse shoe crab) in the presence of pyrogens. The extract from the blood cells of horse shoe crab, Limulus Polyphemus contains an enzyme and protein system called "Limulus- Amebocyte Lysate" (LAL) which reacts with pyrogens so that an assay mixture increases in viscosity and opacity until an opaque gel is formed. Amebocyte + Pyrogen ~ Opaque gel The reaction accomplishes within 15-60 minutes, depending on concentration of pyrogens after mixing. The concentrated pyrogens make the gel more turbid and thick. Requirements Limulus-Ambocyte Lysate is prepared by bleeding healthy mature specimens by heart puncture. The amebocytes are carefully concentrated, washed and lysed by osmotic effects. Prior to perform the LAL test, lysate assay is carried out with purified endotoxins and are accepted if it detects 0.001ug/ml or less concentration of the purified endotoxins. The glassware, such as glass test tubes (10 x 75mm) used in the test must be thoroughly cleaned, dry and heat sterilized. Abuffer solution of potassium phosphate 2mEq/ml is used to adjust the pH of test sample at 7. The alcoholic content in sample is to be removed as it causes precipitation of lysate. If the sample contains proteins, it produces gel thus the proteins must be diluted to appropriate concentration before the test. Similarly other interfering substances present in sample must also be removed before the test. Procedure The pH of test sample if specified is adjusted. The test solution and standardized LAL are separately mixed in equal parts (0.05-0.2ml). The mixture is incubated immediately at 3638°C for 1 hour in assay tube. The assay tube must be remained undisturbed completely because agitation may irreversibly destroy the gel leading to a false negative result. The test tube is observed after the specified time and is examined for the formation of opaque gel.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Formation of gel represents a positive test endpoint reaction. The test is performed using a commercial LAL test kit. This kit contains a lyophilized LAL, and E. coli endotoxin and pure water as standards and these later two are used to check the sensitivity of the test. Advantage of LAL test 1. It is in-vitro and does not require animal handling, thus is more convenient 2. It is 10 times more sensitive than that of the in-vivo rabbit test 3. It is economical 4. It consume less time, i.e., 1 vs 3 hours required by rabbits test 5. It requires less laboratory facilities and minimum equipments 6. It requires less test volume 7. It is more accurate INSTRUMENTS FOR EVALUATION OF PARTICULATE MATTER System Working Principle Remarks Visual Based Inspection Autoskan Light Scattering Non-Destructive Eisai Ampoule Inspection (AIM) System Light blockage (Shadow) Non-Destructive Schering PDS/A-V System Light Scattering Non-Destructive Electronic Particle Counters Coulter Counter Change in Electric Resistance Destructive; Large errors in measuring flakes and fibers; Not recommended by FDA for parenterals HIAC (High Accuracy Instruments) Light Blockage Destructive; High Efficiency, Easy calibration; Recommended by USP; Expensive Met-One Climet Particle Counter Light Scattering Destructive; Measures 6 particles sizes at a time; Excellent large particle detection Climet Instrument Light Obstruction Non-destructive

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

CLARITY TESTING (DETECTION OF PARTICULATE MATTER) Particulate matter can be detected in parenteral product by two methods, including visual inspection and electronic particulate counting. A) Visual methods I) Visual inspection by naked eye In visual inspection, each injectable is inspected visually against white and black backgrounds. The white background aids in diction of dark colored particles. The light or reflective particles will appear against the black back ground. Some visual-enhancing aids can increase the efficiency. A magnifying lens at 2.5 × magnification set at the eye level facilitates the inspection. Microscopic examination enhances detection of particulate matter in injectables. Visual inspection gives the qualitative estimation of the particulate matter. Acceptance Standards is that each container checked must not contain any visible particulate matter. II) Automated visual inspection The automatic systems are also called as the electron particles counter. The electronic particles counter evaluates the particles in injectables automatically. However, this method requires destruction of the ampoule/container for the particle examination. Electronic particles counting may be based on any one of the following principles: a) change in electrical resistance, b) light blockages principle and c) light scattering. Some of the automated systems for visual particle inspection include Autoskan, Eisai Ampoule inspection machine, Schering PDS/A-V system, etc. Autoskan System. The Autoskan system is based on light scattering principle whereby the particle in the path of a light source causes the scattering of light. The scattered light is measured and provides the corresponding information regarding the presence of particulate in the sample. This is a non-destructive test. EISAI AMPOULE MACHINE SYSTEM The Eisai ampoule machine (AIM) system is based on the light blockage principle. The particle size dimensions are determined with the shadow created by the particle under light source. Assessment of the shadow is the indication of the presence of particulate matter. This is also a non-destructive test. Schering PDS/A-V system The Schering PDS/A-V System is based on light scattering by particle if present in the sample. This is also a non-destructive test.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

B) PARTICLE COUNT METHODS Particle count methods are the USP specified microscopic methods, which require the use of optical microscope and automatic microscope. I) Optical Microscopic Method The optical microscopic method requires magnification of 100 k.10x. One eyepiece must be equipped with graticule. A graticule have a series of circles of different diameters, usually in a “under root 2 progression”. The graticule is in circular diameter used to size the particulate. The micrometer is graduated in 10 micro meter increments. A circular diameter graticule II) Automated Particle Counters The automated particle counters are based on the light obscuration, light scattering method and the electrical resistance methods. Coulter Counter counts the particles in a sample based on the change in the electrical resistance. Particle size detection limit in this instrument is from 0.1 to 1000 micrometer. The powder sample requires pretreatment such as dispersion in an electrolyte to form a very dilute suspension. The Suspension is usually subjected to ultrasonic agitation to avoid particle agglomerates. A dispersant may also be added to aid particle deagglomeration. age of particle causes the change in electrical resistance in between the electrodes which is proportional to the volume of particle. The change in resistance is converted into voltage pulse which is amplified and processed electronically and split into the particle size distribution into many different size-range. Glass Tube Orifice Principle of coulter counter This is a destructive test and large errors in measuring flakes and fibers are expected. This test is not recommended by FDA for parenterals. Illustration for a coulter counter High Accuracy (HIAC) Instrument High Accuracy (HIAC) Instrument is based on light blockage principle. The test is highly effective for counting the both solid and liquid suspended particles. The instrument is calibrated easily and the test is recommended by USP. This is destructive test method and is expensive. P Light source Digital Value

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Principle of light blockage Met-One Climet Particle Counter Met-One Climet Particle Counter is based on light scattering principle. The particles are assessed and counted in the sample based on the principle of light scattering. The instrument measures 6 particles sizes at a time and has the excellent ability for the detection of large particle. The test is destructive. Depending on the instrument used, the sample may be presented as the liquid as suspension or air suspension. The light emitted by a helium-neon laser is incident on the sample particle. Light-particle interaction results in scattering of light. The photo detector converts the signals corresponding area/volume diameter of the particle. Instrument based on light scatter principle BIOLOGICAL HAZARDS REPORTED OF PARTICULATE MATTER The particles may localize in lungs, liver, spleen and myocardial tissues and may lead to thrombosis, Particles may lead to myocardial infarction due to embolic fibers. Injection of solution contaminated with particulate matter causes granulomas and emboli in lungs Compendial requirements. Due to having a potential for blockage of the capillaries, an injection must be free from the visual evidence of particulate contamination. Thus, according to the Compendial requirements, each final container of the injectable must be inspected individually and the container must show evidence of contamination with visible foreign material. The in-process quality control test includes the leak and clarity testing. The quality control of finished product required the pyrogen and sterility testing. Leakage test Leakage test is employed to test the package integrity. Package integrity reflects its ability to keep the product in and to keep potential contamination out”. It is because leakage occurs when a discontinuity exists in the wall of a package that can allow the age of gas under pressure or concentration differential existing across the wall. Leakage differs from permeation, which is the flow of matter through the barrier itself. Followings are the leak test methods. A) VISUAL INSPECTION Visual inspection is the easiest leak test method to perform. But this method is least sensitive. The method is used for the evaluation of large volume parenterals. To increase the sensitivity of the method, the visual inspection of the sample container may be coupled with the

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

application of vacuum to make leakage more readily observable. This method is simple and inexpensive. However, the method is insensitive, operator dependent, and qualitative. Sometimes, the method is used in combination with pressure and /or temperature cycling to accelerate leakage to improve sensitivity. B) BUBBLE TEST The test package is submerged in liquids. A differential pressure is applied on the container. The container is observed for bubbles. Sometimes, surfactant added liquid is used for immersion of test package. Any leakage is evident after the application of differential pressure as the generation of foaming in immersion liquid. The method is simple and inexpensive. The location of the leaks can be observed in this method. However, it is relatively insensitive and the findings are operator dependent and are qualitative. The optimized conditions can be achieved using a surfactant immersion fluid along with the dark background and High intensity lighting. Generation of a differential positive pressure of 3 psi inside the vial and observation of any leakage using magnifying glass within a maximum test time of 15 minutes. C) DYE TESTS The test container is immersed in a dye bath. Vacuum and pressure is applied for some time. The container is removed from the dye bath and washed. The container is then inspected for the presence of dye either visually or by means of UV spectroscopy. The dye used may be of blue, green, yellowish-green color. The dye test can be optimized by use of a surfactant and or a low viscosity fluid in the dye solution to increase the capillary migration through the pores. The dye test is widely accepted in industry and is approved in drug use. The test is inexpensive and is requires no special equipment required for visual dye detection. However, the test is qualitative, destructive and slow. The test is used for ampoules and vials. D) VACUUM IONIZATION TEST Vacuum ionization test is useful for testing leakage in the vials or bottled sealed under vacuum. This test is used for online testing of the lyophilized products. High voltage, high frequency field is applied to vials which to cause residual gas, if present to glow. Glow intensity is the function of headspace vacuum level. The blue glow is the indicative of vacuum while the purple glow indicative of no vacuum. The sensitivity of the method is not documented. This test is on-line, rapid and is non destructive test. However, the proteins present in the test sample may be decomposed. This method is used for the lyophilized vials of biopharmaceuticals. CLARITY TESTING Clarity testing is carried out to check the particulate matter in the sample.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Particulate matter Matter of biological or non-biological origin and with observable length, width, and thickness, e.g., bacteria, fungi, dust, dirt, fibers, plastic, rubber, lint etc. It may be any matter, mixed accidentally during manufacturing in the parenteral product which does not belong to the product. Particulate mater may be tiny pieces of lint, glass, dust, rubber, metal fibers, hair, microbes or unidentified and can make the product impure, unclean or unfit for use. Sources of particulate matter Particulate contamination particularly of cellulose fibers, dust, cotton fibers, hair, dandruff and loose skin from human origin as well as microbial contamination may arise from the following main sources. 1. Material arising from the drug: undissolved substances and trace contaminants etc. 2. Material arising from vehicle or added substances: These may include those material not filtered out during a clarification process before to filling the final container. 3. Materials present in the final container: Material already present in container and which were not removed by rinsing prior to filling 4. Materials falling by chance into the final container during the filling process 5. The container or closures which may be deposited in the produce during sterilization, e.g. carbon black, whiting, zinc oxide and clay 6. Packaging components: Including glass, plastic, rubber, I/V istration sets, etc. 7. Environmental contaminants: Including air, work tops, insects’ parts 8. Processing equipments: Including glass, stainless steel, rubber, or filter fiber, etc. 9. Personnel: Including skin, hair, and clothing etc. Particle size Particles present in injectable are non-reactive, apyrogenic, sterilized. However, by virtue of their size may biologically hazardous. The particulate matter may be capable of blocking the blood vessels with severe results on induction into body with injection. A person with 20/20 vision under inspection conditions is able to detect particles of size range 40 – 50 μm. However, it is universally accepted that the particles size of 50 μm is detected visually by an unaided eye. Particle size greater than 7 μm diameter is considered to be more threatening. Pulmonary capillary are approximately 7 μm in diameter, thus particle of this much size entrapped in vascular bed resulting in multiple pulmonary infarction.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

SEALING OF STERILE PREPARATIONS E) Sealing The container should be sealed in the aseptic area immediately adjacent to the filling machine. In addition to retaining the content of the sterile product, sealing of containers assures sterility of its contents. Temper-proof sealing is essential so as the sterility can be ensured until usage. Different approaches have been used for sealing of ampoules and the bottles. Sealing of ampoules The ampoules can be sealed either by tip or bead seal or pull seal. Both of the methods require heating with high-temperature oxygen flame. During sealing, the heating must be even and carefully controlled to avoid distortion of the seal. It is sometimes necessary to displace the air in the space within the ampoule above the product to prevent decomposition. This may be done by introducing a stream of inert gas, such as nitrogen or carbon dioxide, during or after filling with the product. Immediately thereafter, the ampoule is sealed before the gas can diffuse out. The tip seals are made by melting sufficient glass at the tip of the ampoules neck to form a bead of glass and close the opening. Thus, tip seal is also known as bead seals since a bead is formed during melting of the neck. Excessive heat of air and gases in the neck cause expansion against the soft glass with the formation of fragile bubbles at the point of seal. Open capillaries at the point of seal or cracks result in leakers. Fracture of the neck of ampoule often occurs during sealing if wetting had occurred at the time of filling, Also wet glass at the neck increases the frequency of bubble formation and contaminating deposits of carbon or oxides as a result of the effect of the heat of sealing on the droplet of the product. Pull seals are made by heating the neck of the rotating ampoule below the tip, then pulling the tip away to form a small, twisted capillary just prior to being melted closed. Pull sealing is a slower process, but the seals are more reliable than those from the tip sealing. Powder ampoules or other types having a wide opening must be sealed by pull-sealing. With some sensitive products, it may be necessary to seal the ampoules with pull-seals to prevent combustion produces of the flame from entering the ampoule at the time of sealing, as might occur with tip-sealing. Sealing of bottles, cartridges and vials The closure is to be slide from a rotating or vibrating drum to the bottom of a chute, where it is positioned over a container ready for insertion by a plunger or some other pressure device which is followed by stoperring. To facilitate sliding of rubber closures, their surface is halogenated or coated with silicon which reduces the friction during slipping into the container’s mouth.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Aluminum caps are used to hold rubber closures in place. Single caps may have a permanent center hole or a center that is torn away at the time of use to expose the rubber closure. When applied, the bottom edge of the aluminium cap is bent (crimped) around and under the lip of the glass container. It cannot be removed without destroying the cap but perforation permit tearing away the portions of the cap to be discarded. Crimping can be achieved using the heavy duty crimping machines. FILLING OF POWDERS Sterile solids are more difficult to subdivide accurately and precisely into individual dose containers than are liquids. The rate of flow of the solid materials tends to be slow and irregular, particularly if the powder is finally divided. Small granular particles flow most evenly. Uniform particle size and good flow properties of solids are necessary for uniform and effective filling by machines. For powder showing poor flow, the containers with a relatively large opening must be used, even so, the filling rate is slow and the risk of the spillage is ever present. For these reasons, the tolerances permitted for the contents of such containers must be relatively large. Relatively freely flowing solids are filled using filling machines. One type of machine for delivery of measured quantities of solid material employs an augar in the stem of the funnel-shaped hopper. The size and rotation of the augar can be adjusted to deliver a regulated volume of granular material from the funnel stem into the container. In another filling machine, a adjustable cavity in the rim of the filling wheel is filled by vacuum as the wheel es under the hopper. The contents are held by vacuum until the cavity is inserted over the container when a jet of sterile air discharges the solids. This machine also dispenses dry solid that flow less freely. D) FILLING PROCEDURE The filling process has been categorized as the filling of low density and viscosity liquids, filling of viscous liquids and filling of solids. Filling equipment has a reservoir to hold bulk product. The reservoir is connected to delivery tube to dispense product into container. A mean is provided for repetitively forcing a measured volume/amount through the orifice of a delivery tube. The accuracy and the precision of the machine filling of sterile liquids vary with the method. Therefore, a method is selected to provide the degree of accuracy and precision required by the nature of the product. The slightest excess is required in each container to provide for the loss that occurs at the time of the withdrawal of dose at the time of istration due to adherence of container content to the wall of container and retention in the syringe. Filling machines should be designed so that the part through which the liquid flows can be easily demounted for cleaning and for sterilization. These parts also should be constructed of non-

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

reactive materials, such as borosilicate glass or stainless steel. Syringes are usually made of stainless steel, when the pressure required for delivery of the viscous liquid or large volumes would be useful for glass syringes. Filling of low viscosity small volume liquid preparations A liquid may be subdivided from a bulk container to individual dose containers more easily and uniformly than a solid. Mechanical subdivision of a mobile, low density liquid can be achieved with light-duty machinery. Certain fundamental features are found on all filling equipments for liquid preparations. The filling equipment has a reservoir to hold the bulk of the liquid preparation to be filled into containers. A means is provided for repetitively forcing a precisely measured volume of the liquid through the orifice of a delivery tube designed to enter the constricted opening of a container. The size of the delivery tube is governed by the opening in the container to be used, viscosity and density of the liquid and the speed of the delivery desired. The tube must enter freely into the neck of the container and deliver the liquid deep enough to permit air to escape without sweeping the entering liquid into the neck or out of the container. To reduce the resistance to the follow of the liquid, the tube should have the maximum possible diameter. Excessive force of delivery causes splashing of the liquid and troublesome foaming, if the liquid has a low surface tension. The delivery of relatively small volumes of liquids is usually obtained with pressure obtained from the strokes of the plunger of a syringe. The stroke of the syringe forces the liquid through a two-way valve that provides for an alternate filling of the syringe from a reservoir and delivery to a container. A drop of liquid normally hangs at the tip of the tube after a delivery. When the container to be filed is an ampoule, withdrawal of the tube without wetting the long restricted neck is almost impossible, unless the hanging drop of the liquid is retracted. Thus, a retracting device is designated as a part of the most filling machines. Filling of low viscosity large volume liquid preparations Sterile solutions of relatively low potency dispensed in large volumes (up to 1 liter) do not normally require the precision of filling that is required for small volumes of potent injectables. Therefore, the liquid is filled into the bottles by gravity, pressure or vacuum filling devices. Generally, gravity filling is relatively slow, but is accomplished with simpler means. A liquid reservoir is positioned above the filling line, with a hose connection from the reservoir to a shut-off device at the filling line. The shut-off device is usually hand operated, and the bottles are filled to graduations on the bottles. The pressure pump filler often is operated semi-automatically and differs from the gravity fillers, principally in that the liquid is under pressure. It is usually equipped with the overflow tube

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

connected to a receiver to prevent excess flow of the container. Vacuum filling is commonly used in faster filling lines for large liquid volumes because it is more acceptable for automation. A vacuum is produced in a bottle when a nozzle gasket makes a seal against the tip of the bottle to be filled. The vacuum draws the liquid from a reservoir through the delivery tube into the bottle. When the liquid level reaches to a level of an adjustable overflow tube, the seal is mechanically loosened and the vacuum is released. Any liquid that had been drawn into the vacuum line is collected in a trap receiver and then returned to the reservoir. Filling of high viscosity liquid preparations The viscous, sticky or high density liquids require much more heavy machines to withstand the pressure required to dispense them in individual containers. Thus, compared to the plunger-syringe assembly for filling of low viscosity liquid, for heavy, viscous liquids, a sliding piston valve provides more positive action. Emulsion, suspensions and semisolid preparations often require specially designed filling equipments because of their high viscosity. To obtain a reasonable flow rate of the emulsion and suspension, high pressure must be applied or container with large openings must be used to permit the entry of large delivery tubes. Sometimes the jacketed tanks can be used to raise the temperature of the product to facilitate filling by lowering its viscosity. It is normally necessary to keep suspensions and sometimes emulsion, constantly agitated in the reservoir during filling so that the product remains homogeneous and each subdivided unit contains the required amount of drug. C) FORMULATION OF STERILE PRODUCT The product formulation is sometimes, just compounding of the ingredients. In other situations, the parenteral products are formulated as emulsions, suspensions, cream and ointments. All the process are undertaken in strict aseptic conditions. Compounding of ingredients The ingredients should be compounded under clean environmental conditions. A sterile condition is usually not required since it may not be possible or feasible to sterilize some of the ingredients or equipment, e.g., large tanks. Whenever possible, however, the equipments and the ingredients should be sterile to reduce the microbial load. The compounding process should meet the rigid standards accepted in pharmaceutical procedures, regardless of the batch size, recognizing that small multiple errors may be additive. In large batches particular attention must be given to achieving and maintaining homogeneity of solution, suspensions and mixtures, maintaining a given temperature and accelerating cooling. The order of mixing ingredients may become highly significant, for example, owing to the physical problem of disturbing a pH adjusting ingredient throughout a large tank of liquid.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

Compounding problems for large batches of product often are different from those of the small batches. B) Sterilization methods Six sterilization methods are available and are selected based on the item, material of product to be sterilized. These include; 1) sterilization by steam, 2) sterilization by dry heat, 3) sterilization by ethylene oxide, 4) sterilization by filtration, 5) Lyophilization, and 6) sterilization by -radiations. A detail description of the methods has already been given in previous classes. CLEANING RUBBERY PLASTIC COMPONENTS The rubber closures are usually washed by mechanical agitation in a tank of hot detergent solution (such as 0.5% sodium pyrophosphate) followed by a series of through water rinses, the final rinse being WFI. The objective is to remove the surface debris accumulated from the molding operation and from handling and leachable constituents at or near the surface. Part of the debris is attached and held on the surface by electrostatic forces. Similarly, plastic materials accumulate surface debris. The multiple objectives for washing closures and other parts include loosening debris, minimizing abrasion and sweeping away the loosened debris. CLEANING OF CONTAINERS, GLASSWARE AND METAL WARES Like instruments, the unused containers are contaminated with dust, fibers, and chemical films. These are removed by vigorous treatment with hot detergents. The containers are inverted on spindles in the front of the cleaning machine and are automatically conveyed in an inverted position. During rotation of the cleaning machine, they are carried through a series of rigorous, high pressure treatment including hot detergent, hot tap water and final rinses with distilled water. Because many containers have restricted openings, it is essential that the treatments in any washer be introduced though tubes into each container with smooth outflow. For ampoules or containers with a markedly constricted opening that makes water drainage incomplete, the final treatment is usually a blast of clean air to blow out remaining water. After cleaning, it is essential that the clean containers be protected from dust and other particulates that might be present in the environment. Therefore, the clean containers are often removed from the rinser and placed in clean stainless steel boxes for sterilization under the protection of HEPA filtered airflow. Glassware and metal ware (small) may also be contaminated from previous use and can also be mechanically like containers in their converted position during automatically conveying through a series of rigorous, high pressure treatment including hot detergent, hot tap water and final rinses with distilled water. In cleaning new

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

glassware, the detergent treatment is usually eliminated, and with it the risk of the detergent residue. With rinsing alternatively by hot (preferably clean steam) and cold treatments should be used to lessen the debris. Final rinses should be done with filtered WFI. A) CLEANING OF EQUIPMENTS, CONTAINERS AND GLASSWARE (1) Cleaning of Equipments The equipments to be used in the processing of the sterile products must be thoroughly cleaned. The new and unused equipments are contaminated principally with dust, fibers, and chemical films which usually are relatively easy to remove often by rinsing only. Debris that is more dangerous and more difficult to remove may be present as residue from the previous use. These are removed by vigorous treatment with hot detergents. Whenever possible, large equipments should be disassembled so that each part can be thoroughly scrubbed and clean with particular attention given to screw threads, ts and other dirt collecting structures. After cleaning, the equipments should be rinsed several times with final rinse with water for injection (WFI). Just prior to re-use, large cleaned tanks and similar equipments should be rinsed thoroughly with WFI. Reserving of the equipment for use with only one type of the product reduces the cleaning problems. A new method for large tanks, pipe lines and associated equipments that can be isolated and contained within a process unit has been developed and identified as clean in place (CIP) system. Under this system, cleaning of the dedicated instruments for specific products is accomplished primarily with high pressure rinsing treatments, delivered automatically within the equipment. This is usually followed by steam sanitization through the same system. STERILE PRODUCTION PROCESS The general production process started from the accumulation of raw materials, ingredients and packaging components and then combining of the ingredients of the formula into a product. The prepared product is enclosed in the individual containers for distribution. Sterilization during production and/or after production is also employed. During production, in-process quality control and the finished product quality control is also performed. The required equipments are cleaned prior to the start of the sterile production process. STANDARD OPERATING PROCEDURES To enhance the assurance of the successful manufacturing operations, all process steps must be carefully written. The written process steps are often called standard operating procedures (SOP). No extemporaneous changes are permitted in the SOP. Any change in SOP

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

must go through the same approval steps as the original written SOP. According to the FDA guidelines on the good manufacturing practices, extensive records must be kept to assure, at the end of the production process in that all steps have been performed as prescribed. Such in-process control is essential to assure the quality of the product. Since this assurance is even more significant than those from product release testing. Production of quality product is a result of continuous, dedicated efforts of the quality assurance, production and quality control personnel within the plan in developing, performing and confirming effective SOP. The process equipments and the components of the containers, cleaned thoroughly according to the required specifications are assembled in a clean environment. The assembled components are preferably sterilized and depyrogenated prior to use. All equipments and the supplies, introduced into the aseptic filling areas should be sterilized. The outer surfaces of the boxes, packages, or equipments should be wiped with a disinfectant solution as they are transferred to clean room. All the supplies must be introduced into the aseptic filling room in such a manner that the aseptic state of these room is maintained, thereby, preventing the introduction of environmental contamination into the product while it is being subdivided into individual containers. After sealing of containers, contamination cannot enter into the container and the product. Thus the product is sealed in its final container within the aseptic room from where it is transported to packaging area. This area is maintained clean but need not meet the standard imposed for the aseptic room or for the sterile compounding room. Packaged products are placed in quarantine storage until all tests have been completed and in-process control records have been evaluated. PERSONNEL FOR STERILE PREPARATIONS F) Personnel The most ideally planned processes can be rendered ineffective by personnel who do not have the right attitudes or training. The personnel who produce sterile products usually are non-professional person, supervised by those with professional training. To be effective operators, they must inherently neat, orderly, reliable and alert and have good manual dexterity. They should be appreciative of the vital role that every movement lies in determining the quality of final product, it its freedom from contaminants. All employees should be in good health and should be subjected to periodic physical examinations. They should understand their responsibility to report the developing symptoms of cold, sore throat or other infectious diseases, so that they can be assigned to a less critical area until they have fully recovered.

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

The attire won by personnel in the aseptic areas usually consists of sterile coveralls, hoods, face masks and show covers. Sterile rubber gloves also may be required. Personnel entering the aseptic areas should be required to follow a definite preparatory procedure. This should include removing at least outside street clothing, washing the hands and arms thoroughly with a disinfectant soap, and donning the prescribed uniform. A full body water and soap shower would be essential n most biologic products processing plants – usually, both when entering and leaving the area to control contaminations in both directions, between personnel and the product. Since people are continually shedding viable and non-viable particulate matter from body surfaces, uniform are worn to help to control this emission. The uniform should, preferably be of coverall type and made of synthetic fibers such as Dacron. Dacron cloth is made of a continuous fiber, which makes it essentially lint-free and in air conditioned room, is acceptably comfortable. ANOTHER SYSTEM OF CLASSIFICATION FOR CLEAN ARE ANOTHER SYSTEM OF CLASSIFICATION FOR CLEAN AREA Number of Particle Diameter (um)

Class

0.1

0.3

0.5

1

35

3

1

10

350

35

10

300

100

100

5

1000

1000

7

10,000

10,000

70

100,000

100,000

700

Federal Standard 209 (FED STD 209) For Clean Area 1. Class 100,000: Particle count not to exceed a total of 100,000 particles per cubic foot of a size 0.5μ (micron) and larger or 700 particles per cubic foot of a size 5.0μ (micron) and larger. 2. Class 10.000: Particle count not to exceed a total of 10,000 particles per cubic foot of a size 0.5μ (micron) and larger or 65 particles per cubic foot of a size 5.0μ (micron) and larger. 3. Class 1,000: Particle count not to exceed a total of 1000 particles per cubic foot of a size 0.5μ (micron) and larger or 10 particles per cubic foot of a size 5.0μ (micron) and larger. 4. Class 100: Particle count not to exceed a total of 100 particles per cubic foot of a size 0.5μ (micron) and larger. Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

(The Clean Room class is generally achieved in the "at rest" state when there are no people in the room) British Standard 5295 For Sterile Area British Standard 5295 Class 1: The particle counts shall not exceed a total of 3000 particles/m3 of a size of 0.5μ (micron) or greater. The greatest particle present in any sample shall not exceed 5μ (micron). Class 2: The particle count shall not exceed a total of 300,000 particles/ m3 of a size 0.5μ (micron) or greater: 2000 particles/m3 of a size 5μ (micron) or greater: 30 particles of a size 10μ (micron) or greater. Class 3: The particle count shall not exceed 1,000,000 particles of a size of 1 micron or greater: 20,000 particles/m3 of a size 5μ (micron) or greater: 4000 particles/m3 of a size 10μ (micron) or greater; 300 particles/m3 of a size 25μ (micron) or greater. Class 4: The particle count shall not exceed a total of 200,000 particles/m3 of a size 5μ (micron) or greater: 40,000 particles/m3 of a size 10μ (micron) or greater: 4000 particles/m3 of a size 25μ (micron) or greater. (3000 particles/m3 at 0.5um converts to about 85 particles/Ft3) PRODUCTION FACILITIES FOR STERILE PRODUCTS (Continued...) A) Environmental control Effective environmental control, both physical and biologic is essential but the level achievable is related to the characteristics of the facility. Further rigid standards from plant to plant and from geographic location to another are not appropriate. Allowance also must be made for variation in control associated with the seasonal conditions. The standards of environmental control vary depending on the area involved (cleanup, packaging, compounding or filling) and type of product being prepared. Unquestionably, the entire area used for the preparation of a product prepared aseptically (without terminal sterilization) must be maintained under the most rigid control that the existing technology permits. If the product is to be terminally sterilized, somewhat less rigid biologic control of the compounding and filling areas may be acceptable. However, rigid standard of cleanliness must be maintained. High standards of cleanliness, excluding daily use of disinfecting procedures are usually acceptable for the cleanup and packaging areas. B) Traffic control Carefully designed arrangement to control and minimize traffic, particularly ‘in’ and ‘out’ of the aseptic areas is essential. Access by personnel to the aseptic corridor and aseptic compound and filling rooms will be only possible through an airlock. -through openings and

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

double ended sterilizers are provided to permit controlled age of supplies from non-aseptic to aseptic area. Persons should be permitted to enter aseptic areas only after following rigidly prescribed procedures for removing street clothing, washing their hands and putting on gowns, hats, shoes, facemasks, gloves and other prescribed attire. Once they have entered the aseptic area, they should not be permitted to move in and out of the area with out regowning. Personnel assigned to cleaning and packaging should be restricted to these areas. Unauthorized personnel should never be permitted to enter the aseptic area. C) House keeping All equipment and the surrounding work area must be cleaned thoroughly at the end of the working day. No contaminating residues from the concluded process may remain. The ceiling, walls, and other structural surfaces must be cleaned with a frequency which is most appropriate. All cleaning equipments should be selected for its effectiveness and freedom from lint-producing tendencies. It should be reserved for use in the aseptic areas only. D) Surface disinfection After through cleaning all surfaces should be disinfected, at least in the aseptic areas. An effective liquid disinfectant should be sprayed or wiped on all surfaces. Irradiation from ultraviolet lamps that are located provide adequate radiation intensity on the maximum extent of surfaces in a room and that are maintained free from dust and films further reduces the viable microorganisms present on the surface and in the air. Ultraviolet rays may be particularly useful to irradiate the inside exposed surfaces of the processing tanks, surfaces under hoods. The surface of the conveyor belts and the similar confined surfaces those are otherwise, difficult to render aseptic. However they cannot reach unexposed surfaces such as pipe connections to tanks, the undersides of conveyors and the inside of containers. The UV lamps must be kept clean and care must be taken to check for a decrease in effective emission, a natural occurrence due to a change in the glass structure with aging. E) Air control In any area occupied by personnel, air must be exchanged at frequent intervals. Fresh outside or recycled air must first be filtered to remove gross particulate matter. A spun glass, cloth, or shredded polyethylene filter may be used for this preliminary cleaning operation. At times, more than one pre-filter may be used in series, the first one is quite large and the next somewhat smaller pore size to provide a gradation of particle size removal from heavily contaminated air. To remove finer debris down to the submicron range, including

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

microorganism, a high efficiency particulate air (HEPA) filter is used. The HEPA filter has been defined as at least 99.97% efficient in removing particles of 0.3um size and larger and composed of glass fibers and filters or electrostatic precipitators may be employed. Air ing though these units can be considered virtually free from foreign matter. Another air cleaning system washes the air with a disinfectant and controls the humidity at the same time. Blowers should be installed in the air ventilation system upstream to the filters, so that all the dirt producing devices are ahead of the filter. The clean air is normally distributed to the regulated areas by means of metal (preferably stainless steel) ducts. Since it is practically impossible to keep these ducts as clean as required, it is normally preferred to install HEPA filters at the where the clean air enters the controlled room. Alternatively, the ducts may be replaced with a room (a plenum) usually above the production area, into which clean air is blown and then distributed through opening into each of the process rooms. The entire plenum can be kept clean and aseptic. The clean and aseptic air is distributed in such a manner that it flows into the maximum security room at the greatest volume flow rate, thereby producing a positive pressure in these areas. This prevents unclean air from rushing into the aseptic area though cracks, temporarily opened doors or other openings. The pressure is reduced successively so that the air follows from the maximum security area to other less critical areas for return to the filtration system. At the intake end of the system, fresh air usually about 2% is continually introduced for the comfort and needs of the personnel. Further, the air is usually conditioned with respect to the temperature and humidity for the comfort of the personnel and sometimes to meet the special requirements of a product. Horizontal laminar flow hood Vertical laminar flow hood A relatively new air control system, based on laminar flow principle, has greatly improved the potential for environmental control of aseptic areas. Currently, it is the only means available for achieving a class 100 clean room. A class 100 clean room is defined as a room in which the particle count in the air is not more than 100 per cubic feet of 0.5um and lager in size. The air filtered through HEPA filter is blown evenly out of the entire back or top of the work bench or entire side or from ceiling of a room. The air flow must be uniform in velocity and direction throughout any given cross-section of the area, being exhausted from the opposite side. The air velocity employed should be 100 k 20 ft/min. Contamination is controlled because it is swept away with the airflow. Although class 100 work environments are normally specified for the most critical aseptic and or clean operations associated with the parenteral preparations, achieving such levels of

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy

cleanliness is expensive and requires effective maintenance and monitoring. It should be recognized that not all operations associates with parenteral medication require such an environment. To such an end other classes are defined. For example, a class 10,000 room is one in which the particle count is not more than 10,000 per cubic feet of 0.5 um and large size. Such a cleanliness level is usually considered suitable for buffer areas around class 100 worksites in which operations such as handling of pre-cleaned containers, process filtration and aseptic gowning of personnel may be performed. Still less stringent requirements would be applied to laboratories, stock staging areas, and finish packaging where a class 100,000 or similar cleanliness levels would be considered suitable. Different classes and standards of clean rooms: The determination of how clean an area is, depends on the classification that it has been designed with different standards. Four different classes are described according to British Standard system 5295 and Federal Standard 209 (FED STD 209).

Dr. Prafulla Kumar Sahu

Raghu College of Pharmacy