Calibration Tolerance

By Dr Scott Rudge

Editor's Note:  Interested reader Ray Nims points out that I forgot to square the terms in my propagation of error calculation below.  I apologize for the misinformation.  The corrected blog follows:

In calibration, there is a lot of focus on using the right standard.  Standards must be NIST traceable, have current calibration certifications, and have been cared for appropriately.  See for example ANSI Z540.1 or ISO 17025.  Less attention is paid to the appropriate accuracy of the standard.  In this short blog, we will discuss the basis for instrument range, instrument tolerance and standard tolerance.

An early example of a calibrated measurement device

The tolerance of a process for variation in a certain parameter should be set in process development.  Ideally, this is done as part of process characterization, where the effect of parameter variation is measured.  Some examples of operating ranges set in process development are temperature ± 2°C, pH ± 0.2 units and conductivity ± 10 mS/cm.  Ranges this tight put some pressure on calibration to be especially accurate.  After all, if your instrument is reporting a measurement right at the limit of the acceptable range, it’s probably very important that the instrument not be inaccurate by very much, if at all.

The National Conference of Standards Laboratories (now known as NCSL International) recommends that instruments be calibrated with an uncertainty of no more than 25% of the acceptable control range.  This means that the tolerance (or uncertainty) for the instruments measuring temperature, pH and conductivity cited above would be ± 0.5°C, ± 0.05 and ± 2.5 mS/cm, respectively.  These are tight tolerances, but are needed to ensure that the process is really within ± 125% of the target range.

But wait, there’s more!  You can only be sure that the measuring instrument is within tolerance if you know that the uncertainty of the standard used to calibrate it.  Even standards are not necessarily 100.00% accurate, are they?  Standards used for calibration also have a known uncertainty, and again NCSL International recommends at least a 4:1 ratio of standard to instrument uncertainty.  So the standard used for the instruments above should have a tolerance of no more than ± 0.125°C, ±0.0125 and ± 0.5125 mS/cm, or 6.25% of the operating range. This uncertainty also carries through to the uncertainty of the measurement.  Taken absolutely, the widest range possible range is ± 131% of the actual or target range.  However, it should not be assumed that uncertainty randomly falls to the extremes of the allowable ranges.  It is more common to perform a propagation of errors calculation.  Here, the squares of the errors are added, and the square root of the sum calculated, as shown below

This gives a more likely range of ±126%. 

There is a bottom up approach sometimes taken in determining calibration tolerances.  In this approach, the capability of the instrument is used to determine the calibration tolerance.  In other words, if the thermometer is claimed to have an accuracy of ± 0.1°C by the manufacturer, then it should be calibrated with a temperature standard with an uncertainty of no more than ± 0.025°C.  This approach has proven increasingly difficult, as modern technology has increased the capabilities of field measurement instruments.  However, the approach is valid, and some leeway exists (up to a tolerance ratio of 1:1). 

Of course, higher tolerance ratios are permitted.  But these general guidelines should help you design your calibration program so that you know you are making quality measurements in your process.

Relative Humidity Specification at Refrigerated Conditions

By Dr. Scott Rudge

The ICH has established well known temperature and humidity standards for conducting stability studies that mimic the environments in various parts of the world.  Zones I and II correspond to cold and temperate areas respectively, such as North America and Europe, while Zones III and IV correspond to hot and dry or hot and humid climates, like Equatorial Africa, Brazil and lower altitude South America and southern Asia including India.  There are exceptions within these regions, to find out the zone for a specific country, you should reference ICH Q1F or WHO Technical Report Series No. 953, 2009.  These stability conditions are for pharmaceuticals meant to be stored at room temperature.  And it makes sense to consider relative humidity at room temperature, the amount of water in the air can be substantial.  But recently, we’ve had clients specifying a relative humidity in refrigerated conditions.  This is not an ICH requirement, but perhaps with very moisture sensitive products, it makes sense to specify this and control it.

Relative humidity is a fairly familiar concept.  We know that when it’s humid out, it feels hotter.  Your clothes don’t dry, and neither do you!  As I’m sure all the readers of these posts know, “relative” humidity is the amount of water vapor in the air relative the air that is saturated with water.  This is expressed most conveniently as the measured partial pressure of the water vapor in the air divided by the vapor pressure of water at the temperature of the “system”.  The vapor pressure of water is a strong function of temperature, as shown in the following graph:

As the temperature goes towards 0°C, the vapor pressure goes to zero.  It doesn’t reach zero, as ice also has vapor pressure, but it gets close.  At 2°C, the vapor pressure is 5.2 mm Hg at 8°C, it is 8 mm Hg.  So, in the case of a refrigerator, where you might store pharmaceuticals, whatever humidity is in the refrigerator is divided by a very small amount of humidity that represents saturation.  In fact, you would predict that, at a constant partial pressure of water, say 4 mm Hg, the relative humidity would vary with an amplitude of 25% with a temperature range of 4 ± 2°C, as shown below.

 We tested this in one of our refrigerators at RMC, and found the actual situation to be a little worse, an amplitude of about 40%. The amount of water in the air in our 13.75 ft³ refrigerator is 1.65 grams.  That’s quite a bit of water in the air, but a relative humidity profile that seems more or less uncontrollable.

So what’s the answer?  It doesn’t seem that specifying a relative humidity range for a refrigerator is a great idea.  On the other hand, if you have water sensitive samples that are not otherwise protected, you are probably playing with fire.  The use of a desiccant and vapor impermeable overwraps that have been seal tested is probably a requirement.

National Chemistry Week

By Dr. Sheri Glaub

Oct 17-23 is National Chemistry Week . This year’s theme is “Behind the Scenes with Chemistry”, which celebrates the chemistry in movies, set designs, makeup artistry and common special effects.

As exciting at that is, imagine a career working on life-saving therapies. Drug innovations in chemistry have helped increase life expectancy in the US by 30 years over the past century, and many chemical disciplines are involved. For example, medicinal and organic chemists isolate medicinal agents found in plants and create new synthetic drug compounds. Biochemists investigate the mechanism of a drug action; engage in viral research; conduct research pertaining to organ function; or use chemical concepts, procedures, and techniques to study the diagnosis and therapy of disease and the assessment of health. Analytical chemists use their knowledge of chemistry, instrumentation, computers, and statistics to solve problems in almost all areas of chemistry. Their measurements are used to assure compliance with regulations; to assure the safety and quality of food, pharmaceuticals, and water; to support the legal process; and to help physicians diagnose disease. Last, but not least, chemical engineers apply the principles of chemistry, math, and physics to the design and operation of large-scale chemical manufacturing processes. They translate processes developed in the lab into practical applications for the production of products such as plastics, medicines, detergents, and fuels.

This year, the Nobel Prize in Chemistry was jointly awarded to a trio of chemists for palladium-catalyzed cross couplings in organic synthesis. A recent article in Chemical and Engineering News quotes Stephen L. Buchwald, a chemistry professor at Massachusetts Institute of Technology. “This is a very exciting day for organic chemistry. This is a well-deserved award that is long overdue. It is hard to overestimate the importance of these processes in modern-day synthetic chemistry. They are the most used reactions by those in the pharmaceutical industry.”

The future of prescription drugs and medical devices depends on kids getting excited about science now. If you are in the Denver area, make plans to attend the Denver Museum of Nature and Science with your children on October 16 or 17 for the 7th Annual Demonstration and Outreach hosted by University of Northern Colorado Student Affiliate Chapter with advisor Dr. Kim Pacheco. If you are not in the Denver area, check with your local museum or your local ACS section to see what is planned.

Is Bovine Polyoma Virus Getting You Down?

By Dr. Ray Nims

Bovine polyomavirus (BPyV) is a double-stranded DNA virus of genus Polyomavirus. It is non-enveloped and 40-50 nm in diameter, and is a member of the same genus as SV40.

Basis of Concern. The Polyomavirus genus was so-named due to the ability of the viruses to cause tumors in susceptible host animals. Genomic sequences for the potentially oncogenic bovine polyomavirus have been detected with high frequency in bovine sera, regardless of geographic region of origin (Shuurman et al., J. Gen. Virol. 72: 2739-2745, 1991; Wang et al., New Zealand Vet. J. 53: 26-30, 2005).

Regulatory Expectations. Bovine polyomavirus is not mentioned specifically in 9CFR 113.47, Detection of extraneous viruses by the fluorescent antibody technique, as a virus of concern for raw materials of bovine origin. As a result, BPyV is not specifically probed for during most 9CFR 113.53-based raw material viral infectivity testing, and this test most likely would not be capable of detecting BPyV if present in the test material. The EMEA Note for Guidance on the use of Bovine Serum in the Manufacture of Human Biological Medicinal Products (CPMP/BWP/1793/02) states that sera users are “encouraged to apply infectivity assays for BPyV and to investigate methods for inactivation/removal of BPyV in order to limit or eliminate infectious virus from batches of serum”.

Mitigating Risk. In actual practice, the available infectivity assays for BPyV involve numerous passages using a bovine detector cell such as MDBK and are somewhat lengthy and insensitive, though more sensitive assays are under development. Cell-based infectivity testing for BPyV is not always being performed by users for each batch of bovine serum. The lack of a rapid and sensitive infectivity assay also means that viral inactivation studies for BPyV are not practically possible. While another polyomavirus such as SV40 could be used in viral inactivation/removal studies as a proxy for BPyV, in actual practice the murine parvovirus MMV (mouse minute virus) is more typically used as a worst-case model virus for such studies since it is non-enveloped and even smaller than BPyV. The few studies performed with SV40 indicate that gamma-irradiation at the dosages normally employed is not effective at inactivating this virus, as might be expected for a virus of this relatively small size (e.g., Gauvin, 2009). On the other hand, it has been shown (Wang et al., Vox Sanguinis 86: 230-238, 2004) that UVC treatment is effective in inactivating SV40. Note: since originally authoring this blog, I have come across a great number of UV-inactivation papers which indicate that polyomaviruses, and SV-40 in particular, appear to be relatively resistant to UV inactivation. The Wang et al. result may represent an outlier. I will address this in a future blog. Studies using MMV indicate that high-temperature short-time (HTST)-treatment of medium containing bovine serum is effective in inactivating this virus (Schleh et al., Biotechnol. Prog. 25: 854-860, 2009), and would by implication be effective for BPyV.

Conclusions. At the present time, infectivity screening of bovine sera for BPyV is not always being performed, and it is believed that the high frequency of detection of genomic material in bovine sera may not reflect a similarly high frequency of infectious BPyV. Risk of infection of biological products with BPyV through use of bovine-derived materials such as bovine sera may be mitigated through implementation of UVC- or HTST-treatment of media containing the sera and of viral purification processes capable of removing and inactivating an even smaller non-enveloped virus such as MMV.

Can Cache Valley Virus Trash Your Manufacturing?

By Dr. Ray Nims

Cache Valley virus is a single-stranded RNA virus of family bunyavirus, genus Bunyavirus. It is enveloped and nominally 80-120 nm in diameter. Cache Valley virus was first isolated in Utah in 1956 and is carried by mosquitoes. It has since been found to be a widespread virus, having been isolated in Texas, Michigan, North Carolina, Indiana, Virginia and Maryland, for example.

source: Nims et al., BioPharm. Int. 21: 89-94, 2008

Basis of Concern. Cache Valley virus is known to infect livestock, causing birth defects. There have been two reports of encephalitic disease in humans attributed to Cache Valley virus. This virus has been isolated from biologics manufacturing processes employing Chinese hamster cell substrates on a number of occasions from 2000 to 2004 (Nims et al., BioPharm. Int. 21: 89-94, 2008). The route of entry of the virus into biologics production processes has not been established with certainty, although the use of contaminated bovine serum is considered to be the most likely source. Thus far the virus has only been known to infect manufacturing processes employing bovine serum.

Regulatory Expectations. Cache Valley virus is not mentioned specifically in any regulatory guidance, as the detection of this virus in biologics production has been reported only within the past decade. It is the intent of the guidance, however, that occurrences of viral contamination in biologics manufacturing be dealt with through implementation of specific testing methods as required to assure detection of future recurrences (e.g., ICH Q5A R1). In addition, it is expected that the route of entry of the virus be established and that the process be remediated so that future recurrences are prevented where possible (e.g., 1997 Points to Consider in the Manufacture and Testing of Monoclonal Antibody Products for Human Use).

Mitigating Risk. Although many Contract Testing laboratories offer rapid nucleic acid-based detection assays for Cache Valley virus, raw material screening for this virus using such assays does not appear to be a viable means of eliminating risk. The industry experience thus far indicates that Cache Valley virus may be a low level, non-homogeneous contaminant of bovine serum. Viral screening performed on one bottle out of a large lot of serum therefore is no guarantee that this virus will not be encountered. Elimination of animal-derived materials (esp. bovine serum) from the manufacturing process may help to reduce the risk of experiencing this virus. Should this not be possible, treatment of the serum or serum-containing media should be considered. Gamma-irradiation has been demonstrated to be effective in inactivating this virus in bovine serum (Gauvin, 2009). UVC treatment of media containing bovine serum also appears to be quite effective at inactivating Cache Valley virus (Weaver, 2009).

Conclusions. Cache Valley virus infects livestock and has been found to contaminate biologics manufacturing processes employing bovine serum. It is a virus of concern for biologics manufacturers employing bovine serum which has not been gamma-irradiated. Risk of infection of biological products with Cache Valley virus through use of bovine serum may be mitigated through implementation of gamma-irradiation of the serum, or UVC- or high-temperature short-time (HTST) treatment of media containing the serum and of viral purification processes capable of removing and inactivating enveloped viruses.

What cell line is this anyway?

By Dr. Ray Nims

For about as long as scientists have been using cell cultures in biomedical research, there have been cases of cell line misidentification. This has been especially true for continuous cell lines, with the increased probability over time of mislabeling or cross-contamination. The primary cross-contaminant historically has been HeLa, a human cervical carcinoma cell which, given the opportunity, could outgrow most other cells in culture. More recently, the use of feeder cells for the propagation of human stem cells, and the use of xenografting for the propagation of human tumor cells, has provided additional opportunities for cell line cross-contamination and misidentification.


In the past, confirmation of cell line species of origin has been the main approach for authenticating cell lines. This was done initially by karyotyping or by immunological techniques, but more recently it has been done through the technique of isoenzyme analysis. An example of an isoenzyme analysis is shown below for Peptidase B and Aspartate Aminotransferase.  These agarose gels show a positive control, a negative control (this is the band that does not line up with the others), the test article and a standard extract.  These gels confirmed the identity of the test article as mouse derived, as expected. 

Isoenzyme analysis has the advantage that it is rapid, not very technically demanding, and may be used not only to confirm species of origin but also to detect the presence of a cross-contaminating cell if the latter is present in the culture at 10% or greater (Nims et al., Sensitivity of Isoenzyme Analysis for the Detection of Interspecies Cell Line Cross-Contamination. In Vitro Cell. Dev. Biol.-Animal 34:35-39, 1998). In fact, isoenzyme analysis is currently the primary method employed within the biopharmaceutical industry for cell line authentication in satisfaction of 1993 Points to Consider and ICH Q5D guidance.

Recent advances in molecular diagnostic techniques have made possible the authentication of human cell lines to the individual level. DNA fingerprinting technologies have matured to the point that some of them, especially single nucleotide polymorphism (SNP) typing and single tandem repeat (STR) profiling, are now considered to be viable options for standardizing human cell authentication (see ATCC SDO newsletter article, page 5. For both human and animal cells, DNA fingerprinting provides a means of determining authenticity to the individual level. However, the primary drawback is that the fingerprinting techniques as routinely performed will be less or not at all useful for detecting interspecies cocultivations or cross-contaminations. For this purpose, it may be necessary to retain isoenzyme analysis as part of the authentication armament even when the molecular technologies become the definitive authentication practices for human and animal cell lines.

The Good Buffer

By Scott Rudge

“A Good Buffer” has a number of connotations in biochemistry and biochemical engineering. A “good buffer” would be one that has good buffering capacity at the desired pH. The best buffering capacity is at the pK of the buffer of course, although it seems buffer salts are rarely used at their pK.

Second, a good buffer would be one matched to the application. Or maybe that’s first. For example, the buffering ion in an ion exchange chromatography step should be the same charge as the resin (so as not to bind and take up resin capacity). For example, phosphate ion (negative) is a good choice for cation exchange resins (also negatively charged) like S and CM resins.

Another meaning of a “Good” buffer is a buffer described by Dr. Norman Good and colleagues in 1966 (N. E. Good, G. D. Winget, W. Winter, T. N. Connolly, S. Izawa and R. M. M. Singh (1966). "Hydrogen Ion Buffers for Biological Research". Biochemistry 5 (2): 467–477.). These twelve buffers have pK’s spanning the range 6.15 to 8.35, and are a mixture of organic acids, organic bases and zwitterions (having both an acidic and basic site). All twelve of Good’s buffers have pK’s that are fairly strongly temperature dependent, meaning that, in addition to the temperature correction required for the activity of hydrogen ion, there is an actual shift in pH that is temperature dependent. So, while a buffer can be matched to the desired pH approximately every 0.2 pH units across pH 7 ± 1, the buffers are expensive and not entirely suited to manufacturing applications.

In our view, a good buffer is one that is well understood and is designed for its intended purpose. To be designed for its intended purpose, it should be well matched to provide adequate buffering capacity at the desired pH and desired temperature. As shown in the figure, the buffering capacity of a buffer with a pK of 8 is nearly exhausted below pH 7 and above pH 9.

It’s easy to overshoot the desired pH at these “extremes”, but just such a mismatch between buffering ion and desired pH is often specified. Furthermore, buffers are frequently made by titrating to the desired pH from the pK of the base or the acid. This leads to batch to batch variation in the amount of titrant used, because of overshooting and retracing. In addition, the temperature dependence of the pK is not taken into account when specifying the temperature of the buffer. Tris has a pK of 8.06 at 20°C, so a Tris buffer used at pH 7.0 is already not a good idea at 20°C. The pK of Tris changes by -0.03 pH units for every 1°C in positive temperature change. So if the temperature specified for the pH 7.0 buffer is 5°C, the pK will have shifted to 8.51. Tris has 3% of its buffering capacity available at pH 7.0, 5°C, it’s not well matched at all.

A good buffer will have a known mass transfer rate in water, so that its mixing time can be predicted. Precise amounts of buffering acid or base and cosalt are added to give the exact pH required at the exact temperature specified. This actually reduces our reliance on measurements like pH and conductivity that can be inexact. Good buffers can be made with much more precision than ± 0.2 pH units and ± 10% of nominal conductivity, and when you start to make buffers this way, you will rely more on your balance and understanding of appropriate storage conditions for your raw materials, than making adjustments in the field with titrants, time consuming mixing and guessing whether variation in conductivity is going to upset the process.

Enzyme induction…done pharmacodynamically

By Ray Nims

Pharmacodynamics is the study of a specific effect of a drug as related to drug concentration at the putative active-site for that effect. Pharmacodynamics is sometimes used to model quantitatively the effect of a drug over time as drug concentration at the active-site rises and falls. Another type of pharmacodynamic study entails exposing the animal or in vitro system to graded doses of a drug and monitoring the effect associated with each active-site concentration. From the latter type of study, one is able to estimate both potency for the effect (given in terms of the active-site drug concentration at the half-maximal effect for that drug, or EC50) and its efficacy (given in terms of percentage of maximal response compared to other drugs causing the same effect through the same mechanism). In receptor theory, EC50 is considered to reflect the affinity of the drug for a receptor, while efficacy is a measure of the bound drug’s ability to cause the specific response.


The induction of drug-metabolizing enzymes, such as the cytochromes P450, may be considered to represent an effect of a drug or xenobiotic. It is common for investigators to measure such induction at one or a few dose levels and to compare the resulting enzyme induction with that of a prototype inducer. These comparisons are sometimes described in terms of the test xenobiotic causing “strong” (“potent”) or “weak” induction in comparison with the prototype inducer. As already pointed out quite elegantly by D. A. Smith and coworkers (Letter to the Editor: The Time to Move Cytochrome P450 Induction into Mainstream Pharmacology is Long Overdue. Drug Metab. Dispos. 35:697-698, 2007; http://dmd.aspetjournals.org/cgi/content/full/35/4/697), such statements are both misleading and inaccurate. As with any drug effect, enzyme induction must be described in terms of both potency and efficacy. It is possible for an inducer to be very potent but to display little efficacy. In fact, a xenobiotic having high potency and little or no induction efficacy might represent a competitive inhibitor for this effect. In contrast, there may be inducers which are very effective, but not very potent.

It is possible for efficacy and potency for enzyme induction to be estimated on the basis of studies using intact animals, provided that certain assumptions are made (e.g., that total plasma drug concentration is a suitable proxy for drug concentration at the induction active site, which cannot be sampled directly). An example of such a study is that of R.W. Nims and coworkers (Comparative Pharmacodynamics of Hepatic Cytochrome P450 2B Induction by 5,5-Diphenyl- and 5,5-Diethyl-substituted Barbiturates and Hydantoins in the Male F344/NCr Rat. J. Pharmacol. Exp. Therap. 270: 348-355, 1994; http://jpet.aspetjournals.org/cgi/content/abstract/270/1/348). A more straightforward approach is offered through in vitro enzyme induction studies, in which enzyme induction can be related to drug concentration in the culture medium (e.g., Kocarek and coworkers: Differentiated Induction of Cytochrome P450b/e and P450p mRNAs by Dose of Phenobarbital in Primary Cultures of Adult Rat Hepatocytes. Mol. Pharmacol. 38:440-444, 1990; http://molpharm.aspetjournals.org/cgi/content/abstract/38/4/440).

Measurement of the induction of the cytochromes P450 and other drug-metabolizing enzymes following drug treatment in animals and humans is an important aspect of drug characterization. The studies should be performed and reported in a manner consistent with other drug effects, that is, in a manner consistent with the principles of pharmacology.

Got animal-derived materials? Part 2

By Ray Nims

As part of a formal animal-derived materials program, biopharma companies must assess the viral and TSE risk associated with materials derived from animals or which have been in contact with animal-derived materials at some point. We have addressed the viral risk within a previous blog installment. Now let’s consider the TSE risk.

TSEs (transmissible spongiform encephalopathies) are fatal diseases believed to result from exposure of a few animal species (including various ruminants, cervids, ungulates, cats, minks, and humans) to “infectious” prion proteins. The infectious proteins (PrP^Sc) are capable of interacting with and altering the normal prion proteins (PrP^c) within the brain and spinal cord, changing the normal proteins to the abnormal form. Since humans have contracted prion disease as a result of consuming tissues from cattle with bovine spongiform encephalopathy (mad cow disease), there is concern about the use of bovine materials and materials from other “relevant species” in the manufacture of biopharmaceuticals.

The EMEA has provided a guidance document (EMEA/410/01 Rev. 2 October 2003; http://www.emea.europa.eu/pdfs/human/bwp/TSE%20NFG%20410-rev2.pdf) describing the requirements for the use of animal-derived materials from relevant animal species (cattle, sheep, goats, and other animals which are naturally susceptible to TSEs but not including humans or non-human primates) in the manufacture of medicinal or veterinary products. The guidance applies to active substances, excipients and adjuvants, raw and starting materials and reagents, and materials which come into contact with products or equipment used to make product. The major point of the guidance is that TSE risk can be minimized, but in many cases not entirely eliminated. Where TSE risk cannot be avoided through elimination of animal-derived materials completely, the guidance provides principles for the minimization of TSE risk which include: the use of low-risk (non-relevant) animal species, the geographical sourcing of relevant species from low-risk regions, the use of low-risk tissues, the use of appropriate slaughter techniques to reduce potential for contamination of low-risk tissues with high-risk tissues, the appropriate oversight of manufacture of the animal products through Quality Assurance and self and external auditing and Quality Control testing, and the implementation of process designs to remove or inactivate the abnormal prion proteins.

Biopharma companies using animal-derived materials are instructed to perform risk assessments on those materials, which take into account the factors described above. The risk assessments must be completed as part of a formalized animal-derived materials program, documented procedurally and executed by staff that are experienced and trained to conduct such assessments. EMEA inspectors will expect to see this formal program in place. Risk assessments for individual raw materials may then be rolled up into a risk assessment for the biopharma product. The rolled up risk assessment may also consider manufacturing steps at the biopharma which may remove or inactivate the abnormal prion proteins, though these, if cited, may need to be validated. Finally, it is expected that companies will conduct a benefit/risk evaluation to assure that any benefits realized by the patient taking the product will outweigh and justify the risk associated with the use of materials derived from relevant animal species.

Outsource it, and fuggedaboutit?

By Ray Nims

Much has been written about the rationales and advantages for outsourcing of manufacturing and/or testing services; about the selection of outsourcing partners; and about the optimization of the pharma/contractor relationship. In any pharma/contractor relationship, there are responsibilities associated with the pharma as well as contractor responsibilities. These include both business as well as compliance responsibilities. The business realities and regulatory expectations associated with the use, by a pharma company, of a contract testing organization must be considered when the decision is made to outsource. A contract testing organization desiring to provide services for a pharmaceutical must be aware of the expectations and responsibilities associated with such a partnership. The optimal and most defensible programs will be those in which the various practices to be described below are formalized within internal Quality Systems, policies, and/or standard operating procedures as well as Quality Agreements.


Responsibilities falling upon the pharmaceutical partner include: 1) the selection of the contract testing lab; 2) commissioning and providing test samples of raw materials and products for method verification (compendial methods) and method qualification (non-compendial methods); 3) instituting of a Quality Agreements, business agreement, and/or confidentiality agreement with the contractor; 4) scheduling and shipping of test samples in accordance with the requirements of the testing lab and the test system; 5) providing in-life guidance and oversight of investigations of unexpected and out of specification results; and 6) ongoing monitoring of the performance of the contract lab and its methods.

Responsibilities primarily falling upon the testing lab include: 1) attaining and maintaining GLP or GMP compliance as appropriate for the intended use of the method; 2) providing assurance that the methods offered will be available to the client over the long term; 3) responsiveness to the sponsoring pharma and adherence to the terms of the Quality and/or business agreements; 4) method validation, verification, and or qualification as appropriate for the intended use of the method; 5) control of reagent, raw material, control, and standard inventory and quality; 6) assuring secure and retrievable data archiving; and 7) retention of staff possessing the appropriate expertise for direction of operators and the methods.

Ten Steps to Choosing your Contract Manufacturer

For many young companies, choosing a contract manufacturer, or CMO, for their lead pharmaceutical candidate is critical. Choose the wrong contractor, and you could be faced with delays and cost overruns with which your investors and patients won’t be very sympathetic. While there is no guarantee that you will always make the right decision, here are some tips that can help you make your choice in an organized, thoughtful, meaningful and objective way:

1) Make a list of all the possible suppliers. Such lists may be purchased, but they are also easily assembled from internet searches. In fact, you can do a little pre-screening with your own internet search.

2) Screen potential suppliers with a phone call. You will probably speak with a business development or sales person representing the contractor, but usually these people are quite knowledgeable about their company’s capabilities, and common problems encountered in the industry. We recommend you not reveal too many details about your project, and be prepared mostly to listen. However, you should have three or four key capabilities or proficiencies that you are looking for in all of the potential vendors. If possible, try to rule out vendors who do not meet your “must-have” requirements at this stage. Stay tuned for a blog on how to establish your showstopper list, it’s a critical exercise, and may extend beyond key capabilities and proficiencies.

3) Keep a matrix, and record the date you first contacted the vendor, when they responded to you, the status of any confidentiality agreements, and all the contact information that you can gather (email addresses, cell phone numbers, main switchboards and extension numbers). Also note the responses that each contact had relative to your three or four show-stopper criteria.

4) Meet with your team, and select three to five potential vendors to request a proposal from. We don’t recommend more than five: getting good, comparable proposals is a lot of work, like 2n times the work, where n = the number of proposers. Not to mention the work that contract manufacturers go through to read your RFP and prepare a proposal. Your three or four showstopper criteria should help you limit the number of proposers; if necessary you can begin to narrow down based on “nice-to-have” criteria as well. You may also deliberately choose to look at a range of vendors that represent different strengths/weaknesses (for example, do you prefer a “one-stop shop” that is convenient, but maybe not the best at everything, or a “specialty” vendor that provides higher levels of expertise, but will require you to select and manage multiple vendors?).

5) Solicit proposals. Most contract manufacturing seekers have a Request for Proposals (RFP) process that includes a document. These RFP documents vary from one page requirements descriptions, to lengthy, legalistic documents that require a team, and a month, to respond to. You should do what is comfortable for your organization. There needs to be enough information so that the vendor is able to respond with a meaningful proposal. There is some legal danger, particularly with intellectual property, so it’s not a bad idea to get your RFP reviewed by your legal counsel. And you should only send an RFP to a vendor after they have signed a mutually agreed confidentiality agreement.

6) Score your proposals. Find some basis to make apples to apples comparisons. RMC uses a modified Kepner Tregoe analysis, but many forms of analysis will work. You should have determined how you will assess and weight qualitative data before you begin. And in doing so, you should not under-estimate intangible factors: the ability to communicate, time zone differences, good references (you’ve checked, right?) are some examples. At this stage you should be ranking and scoring on “nice-to-have” criteria as well as comparing cost/timeline, capabilities, capacity, and viability of the business. You might form your opinion of the viability of the business by reading annual reports and press releases, and by assessing how busy the manufacturing area and support labs look during your visit.

7) Visit the top two or three vendors in person. Vendors may not allow a formal quality audit prior to signing a contract, but be sure to bring your quality representatives even for an informal “technical visit”. If the project is large, you may take the resistance to a pre-use quality audit as a red flag. Again, spend as much time as possible listening, rather than talking. Get a tour, and copies of all presentations. Ensure that you have a meeting between the decision makers for both sides as well as aligning discussions between key technical and quality personnel. If there are disputes or further work to do, your decision makers must have a good working relationship.
Your visit is also your best opportunity to break past the business development group and take a true measure of the business. Chat with the people in the lab or production area if you can. Look over the state of the equipment, the cleanliness of the facility and the stock in the warehouse. Check their flexibility-- what can they make happen for you, vs. what will have to be run past someone in another building, or another city? Ultimately, you should think about hiring a contract manufacturer similarly to how you hire an employee, by hiring for expertise as well as fit with your team.

8) Consider entering contract negotiations with at least two vendors. Things can go wrong in negotiations, and your position is stronger if you can legitimately walk away. We typically don’t let any of the final three candidates off the hook until the ink is dry on the final contract. If your budget can justify it, having a second contractor performing development work and verifying the primary contractor’s results is an excellent idea. It may ultimately spread your risk in supply chain, and give you leverage in negotiating commercial supply agreements later on.

9) Revisit your analysis tool. You may learn new things in your contract negotiations that cause you to adjust your evaluation. Don’t be afraid to be frank if you feel like terms have been changed since the selection was made. This is a good reason to keep a back up vendor.

10) You must now manage the project according to the criteria by which you selected your supplier. Hold your supplier and yourself accountable to these criteria. For example, after selecting a vendor because they can meet a very aggressive timeline, do not put the project timeline at risk by failing to order back up critical path supplies, in case the primary order doesn’t arrive, or fails to meet specifications on arrival. We will have more to say about managing a contract manufacturer in a future blog.

Choosing the right manufacturing partner is critical for your success as a drug developer. Spend the time required to make a good decision. This time should be spent gleaning as much tangible and non-tangible information on all your options as possible, and then objectively comparing it. You should have an idea about how you’re going to evaluate and weight non-tangible factors into your decision. And once you have made the choice, manage according to your criteria. Although everyone has their own methods for vendor selection, these are some suggestions that have worked well for us and our clients. If you have questions or comments, please visit http://www.rmcpharma.com/ or email us at info@rmcpharma.com.