spacer
home > pmps > spring 2010 > age of aseptics
PUBLICATIONS
Pharmaceutical Manufacturing and Packing Sourcer

Age of Aseptics

Chuck Reed at Weiler Engineering discusses how the latest improvements in aseptic blow-fill-seal (B/F/S) technology are providing streamlined automation of critical B/F/S processing areas, while limiting human intervention and effectively reducing airborne microbial bioburden and particulate levels

Aseptic BFS systems for the processing of pharmaceutical liquids have experienced rapid and growing acceptance by the pharmaceutical industry over the past 20 years. This has been accelerated by enhancements made to aseptic B/F/S processes based on pharmaceutical industry input, as well as to accommodate the requirements of regulatory agencies. These enhancements were designed to improve product integrity and help ensure patient safety. As a result, the US FDA and the US Pharmacopoeia now characterise modern B/F/S technology as an ‘advanced aseptic process’, indicating its use as a preferred technology over other aseptic systems and a better solution for the sterile, aseptic processing of pharmaceutical liquids. Aseptic B/F/S systems offer a unique combination of flexibility in packaging design, low operating cost and a high degree of sterility assurance. Due to its design and functionality, B/F/S processing inherently produces very low levels of particulate matter, and much of the potential for microbial contamination in its critical areas is mitigated by the absence of human intervention.

Microbial contamination is a serious issue for companies manufacturing liquid pharmaceutical formulations. Such liquids are ideal growth areas for bacteria like Salmonella, E coli and Staphylococcus that have been found in various liquid drug products. A supposedly sterile, but contaminated product may result in deterioration of the drug and loss of potency, and with parenterals, this could cause pyrogenic reactions after administration to patients. The majority of liquid drug product contamination over the past several decades has come about from products produced in conventional (non-B/F/S) aseptic processing facilities. In conventional aseptic processing, the drug product, container and closure are subjected to sterilisation processes separately, and then brought together. There is no further processing to sterilise the product after it is in its final container, therefore it is critical that containers are filled and sealed in an extremely high-quality environment.

AUTOMATION UPGRADES IMPROVE STERILITY ASSURANCE IN THE B/F/S ‘CRITICAL ZONE’

Aseptic B/F/S technology integrates blow moulding, sterile filling and hermetic sealing in one continuous operation to produce aseptically manufactured pharmaceutical liquid products. Compared to traditional aseptic processing, the capability for rapid container closure and minimised aseptic interventions is unique to aseptic B/F/S systems.

The most advanced of these systems are extensively automated, designed to require minimum human access and reduce risk to the product’s integrity, while operating in a classified environment. Various in-process control parameters, such as container weight, fill weight, wall thickness and visual defects provide information that is monitored and facilitates ongoing process control. Its containers are formed from a thermoplastic granulate, filled with a liquid pharmaceutical product and then sealed in a continuous, integrated and entirely automated sequence – the critical fill-zone area is shrouded under a continuous flow of positive-pressure sterile filtered air. The B/F/S cycle is completed within seconds. This reduces the amount of components contacting the product, and limits operator intervention, particularly with system changeovers and cleaning.

Recent B/F/S equipment designs employ the use of specialised measures to reduce particle levels and minimise potential microbial contamination of the exposed product in the plastic extrusion and cutting zone. Non-viable particles generated during the plastic extrusion, cutting and sealing processes are thoroughly controlled.

Provisions for carefully controlled airflow protect the product by forcing created particles outward while preventing any inflow from the adjacent environment. This B/F/S zone of protection is continually supplied with HEPA-filtered air, using an air shower device (shroud). Air in the critical filling zone meets Class 100 (ISO 5) microbiological standards during operations. Sterile air management within this critical zone is typically verified through environmental monitoring for the presence of non-viable particulates.

Non-viable particles in the B/F/S process primarily originate from the electrically heated cut-off knife contacting the molten parison (an extruded tube of hot plastic resin through which sterile support air passes during the extrusion sequence). Past attempts to manage non-viable particulate generation in this zone of protection were targeted to the removal of particles after they were produced. Included in recent improvements was the development of parison shrouding, which produces a controlled air environment by employing an exhaust blower system with differential pressure controls in conjunction with containment ductwork in the parison cut-off area, in order to siphon away smoke created by the hot knife (a heated high-resistance wire).

A new technology was introduced to eliminate the generation of the parison-cutting smoke altogether. The mechanism is an automated cold-knife that accomplishes the cutting of the parison without the use of a heated high-resistance wire. It eliminates smoke generation through the application of ultrasonics, effectively reducing particulate generation at the source by more than 99 per cent. It assures that non-viable particles 0.3μm to 10μm in size are significantly reduced in quantity compared with the volume of particles produced during the use of a hot-knife cut-off mechanism.

The FDA’s 2004 Guidance for Industry: Sterile Drug Products Produced by Aseptic Processing states that the design of equipment used in aseptic processing should limit the number and complexity of aseptic interventions by personnel. Both personnel and material flow should be optimised to prevent unnecessary activities that could increase the potential for introducing contaminants to exposed product, container-closures or the surrounding environment. It states further that airborne contamination is directly related to the number of people working in a cleanroom and the level of congregation by personnel in areas where critical aseptic manipulations are performed.

Any intervention or stoppage during an aseptic process can increase the risk of contamination. The design of equipment used in aseptic processing should limit the number and complexity of aseptic interventions by personnel.

REDUCED AIRBORNE MICROBIAL BIOBURDEN IN THE RECENT CHALLENGE STUDY OF ADVANCED B/F/S SYSTEM

Challenge studies on aseptic B/F/S systems performed over the past 20 years have correlated the microbial bioburden of environmental air in a B/F/S fill-room to the potential contamination rate of product which is filled on machines in those rooms. These studies have led to an increased understanding of the capabilities of aseptic B/F/S technology in the production of sterile products.

B/F/S system manufacturers should base their product development on such studies, including materials testing specifically for microbial challenges, which have been supported with scientific evidence that the researched machines function within the standards of accredited agencies.

One of the more recent B/F/S challenge studies was conducted in 2004 by Cardinal Health, Inc and Air Dispersions, Ltd entitled Evaluation of Blow-Fill-Seal Extrusion through processing of Polymer Contaminated with Bacterial Spores and Endotoxin, a study that was carried out to further the understanding of the extrusion process and its impact upon the quality of the B/F/S product. Controlled challenges were conducted for the extrusion system, comprising low-density polyethylene granulate contaminated with Bacillus atrophaeus endospores and E coli bacterial endotoxin.

Sterility of B/F/S polymeric containers, materials and processes is validated by verifying that time and temperature conditions of the extrusion, filling and sealing processes are effective against endotoxins and spores. This report states “The extruder challenge studies, employing spore polymer and endotoxin polymer, have provided definite evidence for polymer extrusion having the capability to produce vials ‘free’ of viable microorganisms and possessing acceptable endotoxin levels.”

The challenge study demonstrates a uniform capability of achieving high sterility assurance levels (10-6 SAL) throughout the entire process. Even higher sterility assurance levels, approaching 10-8 SAL, have been achieved using high levels of airborne microbiological challenge particles.

A critical aspect of B/F/S technology is its pyrogen-free moulding of containers and ampoules. Extensive experiments in this challenge study confirm the efficacy of the B/F/S extrusion process, having been performed using high levels of spores and endotoxin-contaminated polymer granules. Results demonstrated fractional spore contamination levels of less than 1x10-6, and a three-log reduction in endotoxins with the probability of a nonsterile unit (PNSU) approaching one in one million.

EXPANDED OPTIONS FOR B/F/S PACKAGING & DELIVERY SOLUTIONS OF PHARMACEUTICAL LIQUIDS

B/F/S processing resins, polyethylene and polypropylene, used to produce aseptic containers for injectables, ophthalmics, biologicals and vaccines, are generally considered inert by the FDA, and many of the blow moulding resins used in B/F/S processing have received international acceptance as suitable for pharmaceutical liquids applications. These inert materials do not contain additives, have low water vapour permeability, and are easy and safe to handle in critical care environments such as hospitals.

Of particular interest within the pharmaceutical industry is the use of plastic material for the B/F/S production of small volume parenterals. Plastic ampoules offer significant advantages over rubber-stopper glass vials. There is the safety issue – glass vials are subject to breakage, both in transit and while being administered. Handling glass containers always involves a certain amount of risk of lacerations and glass splinters. Glass ampoules generate a fine array of small glass particles during opening. Glass is typically transported in cardboard boxes that can contain mould spores, such as Penicillin sp and Aspergillus sp, as well as bacteria like Bacillus sp. Paper, also used in the shipping of glass, can contain mould spores too. The rubber closures used on the glass containers can have mould contamination.

Aseptic B/F/S-produced small-volume parenterals, such as those used for local anaesthetics, vitamins, vaccines and other standard injectable products, can be manufactured with a twist-off-opening feature. They can also be combined with a controlled-diameter form in the top to accommodate needle-less spikes. Luer locks or luer-slip fits can also be provided for making leak-free connections. For 2 to 5ml small volume parenterals, syringes can be connected directly to the ampoules without a needle, creating an inherently safer packaging solution.

B/F/S-produced, one-piece, plungerless sterile syringes (designed for pre-filling) for use in flushing hospital equipment such as catheters, are available for replacing traditional two-piece plungertype syringes. The B/F/S syringe provides an offset chamber for trapping air, and preventing it from being dispensed during drug delivery.

The increased focus on biologics, proteins and other complex solutions has brought B/F/S technology to the forefront. These pharmaceutical products often cannot withstand exposure to high temperatures for extended periods of time without degradation of their active components, making conventional terminal sterilisation an unacceptable method to produce a ‘sterile’ product. Temperature sensitive biological and protein-based products can be processed in advanced B/F/S machines, providing a level of enhanced sterility assurance. Bulk sterilisation, sterilisation by gamma or e-beam irradiation, or filter sterilisation followed by direct packaging utilising the B/F/S process are used successfully for these types of products. B/F/S demonstrates less than a one-degree Celsius temperature rise in a liquid pharmaceutical which is packaged in a 5ml polyethylene vial.

Advanced B/F/S technology can also include the application of insertion technology to permit the incorporation of a sterile tip and cap insert into the B/F/S package to produce a calibrated drop. This process enables increased efficiency and sterility control in the processing of expensive drug formations for treatment of glaucoma and other eye diseases. Other types of sterile inserts can be incorporated into the basic B/F/S-produced container as well. Top geometrics for both bottles and ampoules can include a multientry rubber stopper or a controlled diameter injection-moulded insert, useful where multiple administration of a drug is required.

Viscous products, with apparent viscosities of less than 15,000 centipoise, and suspension products can be handled by B/F/S machines with specially designed product fill systems. These types of products use innovative liquid-handling systems to maintain multiple component products in a homogeneous solution during the filling process. Basically, if the solution will flow and if it can tolerate a minimum residence time, it can be packaged in an advanced aseptic B/F/S machine.

MEETING THE CHALLENGES OF THE FUTURE

The latest advanced models of aseptic B/F/S systems are capable of manufacturing containers ranging in size from 0.2ml to 1,000ml at production rates of up to 15,000 units per hour. Pharmaceutical companies that use such technological advances in aseptic B/F/S equipment design and systems will realise the highest level of quality in the production of their sterile liquid products. The ability to provide these B/F/S systems, which must meet corporate, scientific, regulatory and end-user requirements, can be quite demanding. These application challenges are being met, however, by continuously evolving and improving B/F/S system and container designs, driven by the need for enhanced product integrity and patient safety.


Read full article from PDF >>

Rate this article You must be a member of the site to make a vote.  
Average rating:
0
     

There are no comments in regards to this article.

spacer
Chuck Reed is the Director of Sales & Marketing at Weiler Engineering, Inc, responsible for corporate sales and marketing activities. He has extensive experience in specialised equipment design and manufacture, process technology and pilot plant design and construction. He is a member of both the PDA and ISPE, is currently Chairman of the ISPE Packaging Community of Practice and is an author for the ISPE Packaging, Labelling and Warehousing (PACLAW) Baseline Guide. Chuck holds a BSc in Chemical Engineering from Clarkson University and an MSc in Management from National Louis University.
spacer
Chuck Reed
spacer
spacer
Print this page
Send to a friend
Privacy statement
News and Press Releases

AstroNova introduces its range of grass paper labels derived from grass for high quality organic products

Dietzenbach, 29 April 2019, AstroNova GmbH, European headquarters of AstroNova Inc. (RI, USA), responsible for Sales and Customer Service in Europe, the Middle East and Africa (EMEA), is extending its Product Identification range with new approved labelling for direct foodstuff contact.
More info >>

White Papers

Clinical Trials in Russia Orange Paper: 2nd Quarter 2014

Synergy Research Group

The Ministry of Health of Russian Federation approved 194 new clinical trials of all types including local and bioequivalence studies during the 2nd Quarter of 2014 (3% less than at the same period of the last year). The main contribution to the total number of studies was made by multinational multi-center clinical trials (MMCT) and the number of these studies stayed the same as in Q2 2013 – 81 studies. The number of bioequivalence studies (BE) decreased from 76 studies in Q2 2013 to 59 in Q2 2014, a 22% decrease from last year’s figure. The number of local clinical trials (LCT) increased from 42 in Q2 2013 to 54 clinical trials in Q2 2014.
More info >>

 
Industry Events

SAPHEX 2019

23-24 October 2019, GALLAGHER CONVENTION CENTRE, 10 RICHARDS DRIVE, HALFWAY HOUSE, MIDRAND, 1685, SOUTH AFRICA

SAPHEX 2019 will be held on the 23rd-24th October at the Gallagher Convention Centre, Johannesburg, South Africa.
More info >>

 

 

©2000-2011 Samedan Ltd.
Add to favourites

Print this page

Send to a friend
Privacy statement