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Site Location Selection: Key to Conducting Better Allergy Clinical Trials

By Renee Butler
On April 15, 2021

Location plays a critical role in many studies, but the impact of geography has a significant impact in allergy and asthma clinical trials. To conduct the highest quality study possible, site selection needs to be aware of the unique challenges and advantages that a particular region possesses. In some cases, this could mean that locations are selected in view of the availability of people with a condition with respect as balanced against the likelihood of background infection (Example: Jamrozik, 2020) while in other cases, the need for caution is much more subtle.

In this article, we will explore the impact of environment on site selection in allergy clinical trials.


Forecasting Pollen and Other Triggers in Allergy Trials

Pollen dispersal is dynamic (Valencia-Barrera, 2002). While routine pollen forecasting is common and effective enough for allergy sufferers, clinical trials are a different matter. There are several methods for making those predictions and results may vary.

Location makes a difference as does precipitation, climate, and other meteorological variables. When conducting a clinical trial around an allergy or asthma trigger, these variables have to be balanced and any differences between site locations or seasons mitigated.

“Clinical trials with pollen allergic patients are in need of validated, high quality pollen data and forecasts in order to grant comparability and to adhere to scientific standards,” explains Bastl et al (2019). “Only institutions with aerobiological knowledge, at best ISO-certified, should be involved in clinical trials and handle the aerobiological tasks.”


Allergy Clinical Trials and Site Location

Pollen isn’t the only allergy trigger that varies by location. Food allergies can be impacted by region as well. Triggers can vary. For instance, if a researcher was looking at wheat and celiac disease (CD), it is vital to note that CD-triggering peptides present in varying degrees by year, crop, and location (Ronga, 2020). Researchers need to balance these factors when evaluating study effectiveness.


Site Selection and Advanced Patient Planning

Location can also have an impact on allergy trials as it relates to patient recruitment (Leslie, 2013). Different countries may have different approved therapies, prompting some patients to seek clinical trials or avoid them. There is also an issue of the suitability of patients for a particular study – specifically those who would “safely obtain therapeutic benefit,” explains Leslie et al. in a recent study. “On a country level, these factors can include a complex mixture of the epidemiological characteristics of the disease, health care and regulatory landscapes, and treatment guidelines for each country and/or region.” Patient behaviors typical of a region should be considered as well.


Conducting Better Allergy Clinical Trials

Allergy clinical trials are unlike other studies. Researchers need to understand current trends in allergy research as well as the biological variables that may be in play. Whether looking at allergy immunotherapy or investigating pollen and asthma, allergies involve environmental variables that have to be balanced for study results to be valid.

Pharm-Olam is equipped to go the distance for your next allergy study. Contact us to request a proposal.

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