Scientists work tirelessly for hours to test various new drugs before they become available to the public. The method they would likely use is called an assay, derived from the old French word ‘Essai,’ which translates to trial. 

Patients voluntarily submit a sample of their blood or another bodily fluid for the clinical trial and testing of the new drug. Once the biological specimen reaches the laboratory, the team can begin to design and develop their assay to ensure they receive accurate data to report to the various parties involved. 

One of their goals would be to determine the drug’s therapeutic window, which defines the boundaries of how much or how little of the drug is required to be effective. Other goals include checking the concentration of a drug in the patient’s samples and refining the composition of the medication. 

For the scientific team to receive viable and reliable samples, certain practices should be followed in order to achieve the best possible results, and some of these are listed below. 

• The Relevance Of The Assay 

Before starting any trial, scientists should decide if the assay will be relevant to their study. Of course, testing is pointless if it won’t benefit the patient or pharmaceutical company. However, the assay must be relevant or specific to the disease or drug the scientists intend to test. 

For this reason, they should determine the disease state, check the concentrations of the compounds they wish to apply to the sample, and ascertain the delivery method, among other variables. Another example of a variation would be to apply different strengths of the compound, which may include the use of diluents on some of the samples. 

Moreover, the scientific team would have to motivate the use of diluents, the specific concentrations thereof, and the effect it had on their results to justify its use in the assay. These may affect the relevance of the assay as some concentrations could deliver inaccurate results, making it useless to the entire process. 

• The Type Of Assay To Use 

Depending on the type of drug or the type of reaction the scientists would like to study, they would need to choose the correct type of assay for the process. Usually, assays are classified into two distinct categories: biochemical and cell-based assays. 

• Biochemical: These assays are generally used for application to enzymes or receptor targets. They produce consistent and reliable results and are more straightforward to use than their cell-based counterparts. Examples of these may include assays for protease cleavage activity, kinase activity, and other protein interactions. 
• Cell-based: Assays of this type could shed light on the activity of a compound at a cellular level. Scientists will often use them as a follow-up to the biochemical assay to measure the toxicity and efficacy of the drug compound as part of a more complex process. Examples of these assays may include viability, migration, and reporter gene assays.

According to their functions, these assays will determine the study’s outcome. It could also contribute to the accuracy of the results. Understanding the primary role of each will assist the team in choosing the correct one for their purpose. 

• The Reproducibility Of The Assay 

Some reactions would need more than one test, or the test would need to be repeated with various concentrations of the drug before scientists can find the therapeutic window. Also, repeating the trial would need to show similar consistent results before they could recommend it for general use by the public.  

The assay design would have to consider the availability of the specific sample, the volume needed for each reproduction, the concentrations of the drug molecules, and the stability of this molecule between samples. 

Technological advances like automation and artificial intelligence improve the reproducibility of assays, as recently used by immunohistology during the pandemic. Adding systems like the Dako Omnis, BenchMark XT, and BOND series to the workflow proved to reproduce more accurate and higher-quality results for lab technicians.

• The Quality Of The Assay 

Scientists will attest that quality is an integral part of the process for any assay. The sample they receive from the patient, the purity of the drug compound, and the reagents they use during the trial will influence the clinical data and, ultimately, the results. 

Strict parameters set before the start of the trial will determine which samples, compounds, and methods would be acceptable for that specific assay. Scientists must set these parameters before testing and ensure they follow these pre-set guidelines throughout if they want a successful assay. 

• The Interferences Of An Assay 

One of the primary tests for the precision of an assay is the inevitable interferences that may arise along the way. In a perfect laboratory environment, scientists can control the outcome. However, as soon as patient samples are involved, a great variety of interferences may affect their testing. 

Patients could have co-morbidities and thus have other medications in their bloodstream that may interact differently with the reagents, solvents, and test methods than the team anticipated. For this reason, scientists should factor into the process the possibility of these interferences and accurately report on them in their final results. 

• The Costs Of The Assay 

Most scientific tests or clinical trials will have a budget the team should strive to stay within. Setting up an assay would need discussions about the required equipment, samples, transport, chemicals, and many other operational requirements to determine the feasibility of the trial. 

If the costs exceed the expected outcome value, many clinical trials won’t be worth the time or effort. 

Setting up a clear budget and applying measures to reasonably limit the various costs of the assay is another practice to consider. Investors often restrict funding, meaning proper financial planning would be essential. 

To Conclude 

Clinical trials that include assays have many considerations and planning to have in place before scientists can start the process. Although these assays are essential to determine drug safety and could consist of years of testing and repeating the process under various circumstances, it may be relatively costly depending on the type of assay and the desired outcome. 

Fortunately, when assays undergo proper planning and execution, the team should attain the results needed for reporting on the feasibility of starting mass production of the drug for the general public. 

These assays are necessary for many health conditions to show improvement as there would be no way to determine the drug treatment’s specific outcome, benefits, or side effects patients must be aware of before submitting themselves to taking these treatments.