Laurence Haren, Dorian Farache, Laurent Emorine, and Andreas Merdes

-tubulin is a major protein involved in the nucleation of microtubules in all eukaryotes. It forms two different complexes with proteins of the GCP family (gamma-tubulin complex proteins): -tubulin small complexes (TuSCs), containing -tubulin and GCPs 2 and 3, and -tubulin ring complexes (TuRCs), containing multiple TuSCs, in addition to GCPs 4, 5, and 6. Whereas the structure and assembly properties of TuSCs have been intensively studied, little is known about the assembly of TuRCs, and about the specific roles of GCPs 4, 5, and 6. Here, we demonstrate that two copies of GCP4 and one copy each of GCP5 and GCP6 form a salt-resistant sub-complex within the TuRC that assembles independently of the presence of TuSCs. Incubation of this sub-complex with cytoplasmic extracts containing TuSCs leads to the reconstitution of TuRCs that are competent to nucleate microtubules. In addition, we investigate sequence extensions and insertions that are specifically found at the amino-terminus of GCP6, and between the GCP6 grip1 and grip2 motifs, and we demonstrate that these are involved in the assembly or stabilization of the TuRC.

Developing safe and effective drugs requires a coordinated effort across a diverse set of disciplines. This is easier to observe at some points in the process than at others. Once a product is well into human trials, it can be easy to forget that developments on the manufacturing side of the house can affect the clinicians who are conducting the studies.




Trialed Drug vs Marketed Drug


Once researchers are satisfied that animal studies show that an Active Pharmaceutical Ingredient (API) is effective and nontoxic at initial doses, there’s an urgency to get it into the clinic and begin human studies as soon as possible. Though the ultimate product may be marketed in one form, a different form may take less time to manufacture, and so would be the form given to human volunteers in earlier clinical trials.

A tablet, for example, is much harder to manufacture than a 2-piece hard shell capsule because determining the appropriate compression for a tablet takes time. (Tablets that aren’t sufficiently compressed will break apart in the bottle; tablets compressed too tightly may not dissolve as they should, earning themselves the entertainingly accurate moniker “bedpan bullets.”) Rather than wait until a tablet form of the drug can be fully developed, to save time, sponsors would likely begin human studies using a hard shell capsule version.*

To ensure that clinical trial data for the Investigational Product (IP) are applicable to the ultimately marketed product, clinicians run bioequivalence for dosage form studies. These small pharmacokinetics studies may result in changes, such as dosage amount or frequency, if people do not metabolize the studied formulation and the final formulation the same way.


Stability Test Failures

When we hear of a pharmaceutical company having to “pull its product,” we typically think of a recall scenario that involves consumers, distributers, and retailers.  Recall procedures fall under the GMP umbrella, and are spelled out in great detail in 21 CFR Part 211. However, similar procedures may very well be required of clinical site staff, long before the product ever sees its first drugstore.


Before any clinical trials begin on a drug, manufacturers would have been conducting stability tests for months. But stability testing may continue for years after the start of human trials, and analysts could detect a variety of troubling conditions in the course of their work. Product can change color or break apart. Capsules can crack and leak. Microbes could begin to grow, especially in moister product. The container closure system itself could be problematic; it could leech contaminating material into the product, introducing impurities, or it could extract material from the product, diminishing its potency. Any of these finding could mean that study drug would need to be pulled from clinical sites.

No one expects site staff to have detailed quarantining and recall procedures; the Sponsor will tell site staff exactly what they need to do. But what would this look like?

(1) Adulterated product that cannot be dispensed will need to be moved to a separate, secure area so it won’t be confused with good product. It might need to be stored there for a period of time or shipped back to the Sponsor.

(2) For certain, a site’s drug accountability procedures will be center stage. The only way a site can successfully recall bad product is if it has -- all along -- closely tracked the amount of IP it has received, dispensed, and still has on hand.

(3) Study participants who have any quantity of the bad product will need to be contacted, told not to use it, and told how to return it. (Note that this pertains to participants on the placebo arm as well, otherwise the blind will be broken.) Phone calls may not be sufficient; sites may need to invoke lost-to-follow-up procedures, such as sending registered letters. Remote, virtual trials, which often ship IP to participants, need to be designed to allow for the tracking and retrieval of bad product.

(4) What should be done if it turns out some participants have already used the bad product? Unfortunately, that’s one SOP you can’t write in advance; it would completely depend on the nature of the IP and the problem it has, the vulnerability of the patient population, the protocol, the participant’s proximity to the site, etc. Perhaps a careful case review to look for AEs associated with affected participants would suffice. More critical situations may require participants to undergo physical examinations or special testing. In many cases, study data associated with the use of the tainted IP would need to be identified and removed from the efficacy analysis.

(5) These quarantining and recall activities must be carefully recorded. IRBs and regulators will want written proof that all suspect IP has been accounted for. Sponsors might consider sending a CRA to ensure adequate documentation.


Re-labeling

Stability tests don’t have to fail to trigger action for clinical staff. Should a chemist discover a condition that requires a labeling modification -- a new expiry date**, for example – all the labels on existing product held at clinical study sites would need to be replaced. In these situations, the Sponsor may dispatch CRAs to replace the labels themselves, or negotiate with individual site staffs to do it instead. 


No GxP is an Island…

GMP professionals manufacture, package, and label biopharmaceutical products. GCP professionals conduct clinical trials on those same products. These roles are very different from each other, yet they don’t work in isolation. Formulation changes, stability testing, and re-labeling requirements represent three examples in which activities performed by GMP folks impact their GCP counterparts. Have you experienced any additional examples? Feel free to share them in the Comments section.

In case you missed it, our last post was about how attributes of the Study Drug influence the Site Selection and Feasibility process.

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* “By the time clinical trials start, they know what ingredients go in the cookie, they just don’t know how the cookie is going to turn out yet.”
       - Rosanne Sylvia-Heeter, Polaris Director of GMP Compliance and phenomenal cook

** Expiry dates are not required but are sometimes included on IP labels.

Last month, I scheduled one-on-one discussions with our most experienced GCP auditors to ask each of them the same question: What surprises you most about the audits you conduct?

I guess you could say that I was the one who was surprised. I’m not sure exactly what I was expecting to hear, but I thought my teammates were going to talk about things that were new. Instead, I heard a lot more about things that have been around for a long time. To a person, my colleagues said they were surprised to be observing some of the same audit findings they were observing 30 years ago...which *is* surprising when you consider most of them were mere children at the time. ;-)  It seems we have some stubbornly persistent quality and compliance issues in the biopharma industry that decades of neither experience nor technology have seemed to remedy. And the problems are not just persistent; they’re interrelated.



Standard Operating Procedures (SOPs)
It’s quite common for auditors to encounter sponsors, CROs, and sites that lack an adequate set of SOPs to describe local procedures. There are several reasons for this. Sometimes it’s a lack of resources. Sometimes smaller, established organizations believe writing it all down is unnecessary, as “people know their jobs.” Sometimes newer companies are simply unaware that written procedures are required for particular operations. But when procedures are not documented, organizations are unable to demonstrate GCP compliance, cannot ensure that activities are performed correctly or consistently, and have difficulty training new staff members. (We’ll come back to training in a bit.)

Frequently missing from a good working set of SOPs are procedures for Disaster Recovery, Handling of Suspected Fraud, and Management of Regulatory Inspections. These SOPs are not used for day-to-day operations, so perhaps that’s why they don’t garner as much attention. Nevertheless, the inability to recover from a disaster, protect the organization from fraud allegations, or pass a regulatory inspection can sink a company.

A fourth SOP that is commonly absent from the set is the document that describes how to write, approve, distribute, revise, and retire SOPs. Also frequently missing from a working set of SOPs is our next topic: Training.

Training
Training can be expensive and time-consuming, and companies increasingly have to do more with less. In-person training has largely been replaced by computer-based systems, on-site training has given way to distance learning, and mentoring has gone the way of the dodo.

The good news is that study sites typically adhere to formal GCP training requirements. What’s often missing, though, is the training that connects GCP concepts to everyday activities. A trainee might correctly answer a multiple-choice question about audit trails, but without that “last mile” of coaching, use Wite-Out to correct a source document error. This is where SOPs come in. When training is conducted using well-written SOPs, it can help bridge the gap between standard GCP training and specific site operations.

It is not uncommon for study-specific training to be lacking in CROs – protocol training, device training, computer systems user training. As part of their vendor oversight procedures (also an SOP!), sponsors should be making sure that CRO staff is adequately trained. 

Trial Master Files (TMFs)
Whether paper or electronic, it’s common for TMF documents to be missing or expired. Replacements for these documents can usually be produced and filed at the time of the audit. Misfiled documents are another matter; they are already there but cannot easily be found. Locating and refiling them essentially doubles the time and cost of the original effort. For example, documents from multiple labs, such as certificates, credentials, vendor audit results, etc., are often mistakenly commingled. Documents must be sorted and refiled so that each facility listed on the 1572 has its own file or electronic folder.


Another very common mistake is treating every document on letterhead as if it’s general correspondence. Search for the word “letter” in the DIA Reference Model and you can see how many opportunities exist for misclassifying correspondence. For example, an IND safety report sent by the sponsor on letterhead should be filed under “Notification of Safety Information,” Section 8.3.18 in ICH E6(R2), not “Relevant Communications,” Section 8.3.11. In an eTMF, an IRB approval letter belongs in 04.01.02, its designated DIA Reference Model position, not 04.04.01, which is reserved for general communication.

The root cause of these misfilings? The filer does not know enough about the filing structure of the TMF and often is not familiar enough with clinical research to know the purpose of each document and where it belongs. The corrective action? Training. Training on the TMF plan, the TMF Management SOP, ICH GCP, and study operations in general.

Technology to the Rescue?
No doubt, CTMSs, eTMFs, eCRFs, ePRO, and other systems have improved clinical operations and reduced error. However, three decades of technological advances have done little to address the most common quality and compliance issues encountered by GCP auditors – and by extension regulators. Some might find that discouraging, but isn’t it also a little satisfying that the solution to our most persistent problems comes down to human communication?

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A version of this article originally appeared in InSite, the Journal of the Society for Clinical Research Sites.

[New York] : Association for Computing Machinery